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test |
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1. an examination or trial. 2. a significant chemical reaction.
3. a reagent. |
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Test |
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See also under method, phenomenon, reaction, reagent, sign, and
symptom. |
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ABLB test, alternate binaural
loudness balance t. |
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abortus Bang ring test, ABR test, (screening
for brucellosis in cattle) since Brucella agglutinins, as well
as the organisms, are shed in the milk of infected cattle, a
drop of hematoxylin-stained brucellae is mixed in a sample of
pooled milk from the herd. After incubation, agglutinated
bacteria are adsorbed by the globules of fat that rise to the
surface to form a colored ring. Called also milk ring t. and
ring t. |
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acid elution test, (for fetal hemoglobin)
air-dried blood smears on a glass slide are fixed in 80 per cent
methanol and immersed in a buffer at pH 3.3 (citric acid and
sodium phosphate); all hemoglobins are eluted except fetal
hemoglobin, which remains fixed in the red cells and can be
detected after staining. Called also Kleihauer or
Kleihauer-Betke t. |
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acidified serum test, (for paroxysmal
nocturnal hemoglobinuria) the patient's washed red cells are
incubated at 370C in acidified normal serum or the patient's
acidified serum; after centrifugation the supernatant is
examined colorimetrically for hemolysis. In paroxysmal nocturnal
hemoglobinuria the red cells are abnormally susceptible to lysis
by complement, which is activated by the alternate pathway in
acidified serum. Called also Ham t. |
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acid-lability test, a test to distinguish
rhinoviruses from enteroviruses on the basis of their activity
at various pH levels, rhinoviruses being inactivated by
incubation at pH 3 to 5 for one to three hours. |
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acid perfusion test, Bernstein t. |
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acoustic reflex test, measurement of the
acoustic reflex threshold by testing for contraction of the
stapedial muscle in response to sound; used to differentiate
between conductive and sensorineural deafness and to diagnose
acoustic neuroma. |
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Addis test, after the patient is given a dry
diet for 24 hours, the specific gravity of the urine is
determined. |
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Adson test, see under maneuver. |
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agglutination test, (for presence of
antibody) cells containing antigens to a given antibody are
mixed into the solution being tested; agglutination indicates
presence of the antibody. See also agglutination reaction and
latex agglutination t. |
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AL test, a type of patch test in which the
materials being tested are applied to cellulose disks arrayed on
polyethylene-coated aluminum paper, which is affixed to the skin
for several days. |
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alkali denaturation test, (for
fetal hemoglobin) a spectrophotometric method for determining
the concentration of hemoglobin F, which depends on the
resistance of the hemoglobin molecule to denaturation of its
globin moiety when exposed to alkali. |
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Allen test, (for occlusion of ulnar or
radial arteries) the patient makes a tight fist so as to express
the blood from the skin of the palm and fingers; the examiner
digitally compresses either the radial or the ulnar artery. When
the patient unclenches the fist, if blood fails to return to the
palm and fingers, there is indicated obstruction to blood flow
in the artery that has not been compressed. |
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Allen-Doisy test, (a formerly common test
for estrogens) the material being tested was injected into
spayed laboratory mice and a change from leukocytes to cornified
cells in their vaginal secretions was a positive result. |
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alternate binaural loudness
balance test, comparison of the intensity levels at which a
given pure tone sounds equally loud to the normal ear and the
ear with hearing loss; done to determine recruitment with
unilateral sensorineural loss. Called also ABLB test. |
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alternate cover test, a test for determining
the type of tropia and/or phoria done by alternately covering
each eye and noting the movement of the uncovered eye. |
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alternate loudness balance test, a hearing
test done with pure tones that compares the loudness perceived
in one ear with that perceived in the other, with the frequency
kept constant. |
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Ames test, a test for
mutagenicity of chemical compounds, using special strains of the
bacteria serovar Salmonella enterica subsp. enterica serovar
Typhimurium. The bacteria are incubated on a histidine-deficient
medium in the presence of the suspected mutagen and rat liver
microsomal cell fraction, which contains mixed-function oxidases
known to activate many procarcinogens. Growth of bacterial
colonies indicates mutagenicity (reverse mutations restoring the
ability to synthesize histidine have occurred). About 90–95 per
cent of demonstrated mutagens are also carcinogenic. |
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aminopyrine breath test, a breath test done
to measure liver function. The patient is given a dose of
14C-labeled
aminopyrine and at 15-minute intervals for two hours the amount
of 14C-labeled
carbon dioxide in the patient's breath is measured. Excessively
low levels of carbon dioxide indicate impaired liver function,
such as cirrhosis. |
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anterior drawer test, see drawer
t's. |
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antibiotic sensitivity test,
antibiotic susceptibility test, antimicrobial susceptibility t. |
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anti-DNA test,
anti?double-stranded DNA test, an enzyme immunoassay that uses
native double-stranded DNA as an antigen to detect and monitor
increased serum levels of anti-DNA antibodies, a sign of
systemic lupus erythematosus; used in both detection and
management of disease. |
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antiglobulin test, a test for the presence
of nonagglutinating antibodies against red blood cells, using
antihuman globulin antibody to agglutinate cells coated with the
nonagglutinating antibody. The direct antiglobulin test detects
antibodies bound to circulating red cells in vivo. It is used in
the evaluation of autoimmune and drug-induced immune hemolytic
anemia and erythroblastosis fetalis. The indirect antiglobulin
test detects serum antibodies that bind to red cells in an in
vitro incubation step. It is used in typing of erythrocyte
antigens and in compatibility testing (cross-match). Called also
Coombs t. |
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antiglobulin consumption test, a test for
serum antibodies against cellular antigens. Cells are incubated
with the serum sample and then with antiglobulin; any serum
antibody that binds to the cells will take up antiglobulin. The
amount of antiglobulin consumed is determined by testing the
supernatant with antibody-coated red cells; the amount of
agglutination is inversely proportional to the antiglobulin
consumption. |
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antihuman globulin (AHG) test, direct
antiglobulin test; see antiglobulin test. |
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antimicrobial sensitivity test, antimicrobial susceptibility
test, any of numerous tests of how
susceptible bacteria are to antimicrobial agents; the bacteria
are classified as either sensitive or susceptible, indeterminate
or intermediate, or resistant. Called also antibiotic
sensitivity or antibiotic susceptibility t. |
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Apley compression test, (for torn
meniscus) with the patient lying prone and the examiner's knee
placed on the posterior thigh of the leg being examined, the
examiner flexes and externally rotates the tibia while gripping
the ankle, then presses the tibia downward. An increase in pain
on compression indicates a torn meniscus. |
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Apt test, (for differentiating fetal from
adult hemoglobin) a specimen from an infant's vomitus or stool
is mixed with 5 volumes of water and centrifuged so that a clear
pink supernatant separates. Sodium hydroxide solution is added
to the supernatant; if hemoglobin F (fetal blood) is present,
the pink color persists for more than 2 minutes, whereas if
hemoglobin A (from swallowed maternal blood) is present, the
supernatant turns from pink to yellow within 2 minutes. |
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aptitude tests, tests given to determine
aptitude or ability to undertake study or training in a
particular field. |
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arm ergometry exercise test, a
variant of the bicycle ergometer exercise test in which the
patient uses the arms to pedal the bicycle. |
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arylsulfatase test, (for differentiating
species of rapid-growing mycobacteria) a sample from a
Tween-albumin broth culture of the suspected organism is
incubated with tripotassium phenolphthalein disulfate for three
days and then alkalinized. Those species producing arylsulfatase
(Mycobacterium fortuitum and M. chelonae) show a pink to red
positive reaction; a colorless reaction is negative. |
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aspirin tolerance test, any of various
bleeding time tests in which aspirin is administered and its
effect on bleeding time is assessed; aspirin prolongs bleeding
time in patients with von Willebrand disease and certain other
platelet disorders. |
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association test, a test based on
associative reaction. It is usually performed by mentioning
words to a subject and noting what other words he or she will
give as the ones called to mind. The reaction time is also
noted. |
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atrial pacing stress test, a
stress test in which temporary immediately reversible atrial
pacing is used to stress coronary reserve; used for patients
incapable of exercise or in whom an exercise stress test is
contraindicated. |
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augmented histamine test, (a newer type of
histamine test for gastric function) after a 12-hour fast,
residual gastric contents are aspirated. Basal gastric secretion
is then collected every 15 minutes for 1 hour; at the 30-minute
point, antihistamine is given intramuscularly. At the end of the
hour, histamine acid phosphate (0.04 mg per kg of body weight)
is given subcutaneously, and gastric contents are collected
every 15 minutes for another hour. Volume, pH, and titratable
acidity are measured on each sample. |
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autohemolysis test, (for
hereditary spherocytosis) a sample of blood is defibrinated and
incubated at 370C for 24 and 48 hours; if hereditary
spherocytosis is present, spontaneous hemolysis is increased. |
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automated reagin test, a
modification of the rapid plasma reagin test for syphilis, used
with automated analyzers in clinical chemistry. |
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Ayer-Tobey test, Tobey-Ayer t. |
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Babinski test, see under sign. |
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Babinski-Weil test, (for labyrinthine
disease) the patient, with eyes shut, walks forward and backward
ten times; with labyrinthine disease there will be deviation
from the straight path, bending to one side when walking forward
and to the other when walking backward. |
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bacteriolytic test, Pfeiffer
phenomenon. |
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Baermann test, (for extraction of
soil nematodes from earth and detecting larvae of Strongyloides
stercoralis in feces) a specimen of soil or feces is suspended
over gauze or wire mesh in a water-filled funnel to which a
piece of rubber tubing is attached; larval nematodes migrate
from the specimen to the water, and collect in the rubber
tubing. |
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Bang test, abortus Bang ring t. |
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Bárány test, caloric t. |
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Bárány pointing test, the patient points at
a fixed object alternately with the eyes open and closed; a
constant error with the eyes closed indicates a brain lesion. |
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barium test, gastrointestinal
series. |
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bar-reading test, a test for binocular and
stereoscopic vision, which consists of holding a ruler midway
between the eyes and the printed page. It is also used as an
exercise to develop stereoscopic vision; called also Welland t. |
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basophil degranulation test, an in vitro
procedure testing allergic sensitivity to a specific allergen at
the cellular level by measuring staining of basophils after
exposure to the allergen; a reduction in the number of
granulated cells is a positive result. |
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Becker test, (for astigmatism)
the patient looks at a test card containing lines radiating in
sets of three and points out which seem blurred. |
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Bekhterev (Bechterew) test, the patient
seated in bed is directed to stretch out both legs; in sciatica
they cannot do this, but can stretch out each leg in turn. |
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Bender Gestalt test, Bender Visual-Motor Gestalt test,
a psychological test used for evaluating
perceptual-motor coordination, for assessing personality
dynamics, as a test of organic brain impairment, and for
measuring neurological maturation. The subject is asked to make
free-hand copies of nine simple geometric designs presented
separately on cards or sometimes to reproduce the design from
memory. |
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Benedict test, (for glucose in
urine) a test for glucose in the urine using Benedict reagent. |
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bentiromide test, (for pancreatic
function)bentiromide is administered orally and its cleavage
into benzoyl-tyrosyl and p-aminobenzoic acid is monitored as a
measure of pancreatic production of chymotrypsin. |
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bentonite flocculation test, any
agglutination test using antigen adsorbed on particles of
bentonite; when the antigen is added to serum containing
specific antibodies, flocculation occurs. |
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benzidine test, (for occult blood in urine
or feces)benzidine, acetic acid, and hydrogen peroxide are added
to the specimen; hemoglobin catalyzes the oxidation of benzidine
by hydrogen peroxide, giving a blue color. This is the most
sensitive screening test for occult blood, but it is seldom used
because benzidine is a carcinogen, and its use is restricted. |
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Bernstein test, (for diagnosis of
gastroesophageal reflux) 0.1 N hydrochloric acid infused at a
rate of 120 drops per minute produces pain and other symptoms.
Called also acid perfusion t. and esophageal acid perfusion t. |
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Bial test, (for pentoses in urine) the
specimen is heated with a solution of orcinol, hydrochloric
acid, and ferric chloride; pentoses are converted to furfural,
which reacts with orcinol to form a green product. |
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bicycle ergometer exercise test,
an exercise test in which the patient pedals a stationary
bicycle ergometer; the test is usually graded, with incremental
or continuous increases in power produced by increases in pedal
resistance at a given pedal speed. Cf. treadmill exercise t. |
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Bielschowsky head-tilting test, (for types
of paresis) tilting the head to the right and the left shoulder
with the patient looking at a distance fixation device permits
distinction between superior rectus paresis and contralateral
superior oblique paresis. |
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bile acid breath test, a breath test for
overgrowth of bacteria in the intestine: the patient is given a
dose of a conjugated bile acid labeled with carbon 14 and the
amount of radioactively labeled carbon dioxide in the breath is
measured at hourly intervals. Excessive labeled carbon dioxide
in the breath indicates excessive bacteria in the intestine
breaking down the bile acids. |
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bile solubility test, (for differentiation
of pneumococci from other streptococci) a sample of a broth
culture is incubated at pH 7.4 to 7.6 with sodium deoxycholate.
A decrease in turbidity (positive test) indicates lysing of the
cells. Pneumococci give a positive result, whereas other
viridans streptococci give a negative one. |
|
biliary drainage test, examination of the
contents of the duodenum at the site where the common bile duct
empties into it; this is done when other, more conventional
diagnostic tests for gallbladder disease reveal no pathology but
the patient's symptoms persist. Specimens are collected with a
special tube and examined for leukocytes, cholesterol crystals,
and parasites. |
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bilirubin test, see specific tests,
including Fouchet t. and Harrison spot t. |
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binaural distorted speech tests, tests of
the capacity of the central nervous system to coordinate two
incoming speech patterns, each of which is incomplete. |
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Binet test, Binet-Simon test, a method of
testing the mental capacity of children and youth by asking a
series of questions adapted to, and standardized on, the
capacity of normal children at various ages. According to the
answers given, the mental age of the subject is ascertained. |
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Bing test, (for hearing) a vibrating tuning
fork is held to the mastoid process and the auditory meatus is
alternately occluded and left open: changes in loudness
(positive Bing) are perceived by the normal ear and in
sensorineural hearing loss, but in conduction hearing loss no
difference is perceived (negative Bing). |
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biuret test, a colorimetric test
for protein that makes use of the biuret reaction (q.v.). |
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bleeding time test, a test of bleeding time,
assessing capillary function and platelet function, such as Duke
t., Ivy t., or the template method. |
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Bodal test, test of color perception by the
use of colored blocks. |
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bone conduction tests, tests of
bone conduction; see tuning fork t's. |
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Bozicevich test, a serologic test
for the detection of trichinosis. |
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breath test, any of various tests in which a
person's breath is analyzed for presence of something abnormal.
Subgroups called the 13C breath tests and 14C breath tests
involve administration of organic compounds labeled with carbon
13 (heavy carbon) or carbon 14 (radioactive carbon) and
measuring the subsequent levels of labeled carbon dioxide in the
patient's breath; the labeled compound may be found to be
metabolized normally, too fast, or too slow in the
gastrointestinal tract. |
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breath hydrogen test, hydrogen
breath t. |
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Broadbent test, (for cerebral dominance of
language function) different numbers (or words) are presented
simultaneously to the two ears; right-handed persons tend to
report first the words going into the right ear. |
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bronchial challenge test, see
under challenge. |
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buccal smear test, sex chromatin
t. |
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Burchard-Liebermann test,
Liebermann-Burchard t. |
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χ2 test, chi-square t. |
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caffeine breath test, a breath test for
liver function: the patient is given a dose of caffeine labeled
with carbon 13; excessively low levels of labeled carbon dioxide
in the patient's breath indicate inadequate metabolism of it by
the liver, as in patients who have cirrhosis or who smoke. |
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calcium infusion test, (for
hyperglycinemia)calcium gluconate is administered to the fasting
patient for 180 minutes. Serum samples are obtained 30 minutes
before infusion, at its initiation, and every 30 minutes for two
hours afterwards. The patient with a gastrinoma will show a
sharp rise in production of gastrin. |
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California mastitis test, (for
subclinical mastitis in cows) equal amounts of milk, bromcresol
purple, and an anionic surface-active substance are mixed in
four separate cups within a plastic paddle by rapidly rotating
the paddle horizontally; a positive reaction is indicated by
various degrees of gel formation, according to the degree of
abnormality of the milk. |
|
caloric test, (for ocular and vestibular
functioning) irrigation of the normal ear with warm water
produces rotatory nystagmus (caloric nystagmus) toward the
irrigated side; irrigation with cold water produces similar
nystagmus away from that side. Called also Bárány t., sign, or
symptom and nystagmus t. |
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CAMP test, (for the presumptive
identification of Group B beta-hemolytic streptococci) a culture
of streptococcus is streaked on a blood agar plate near a streak
of beta-lysin–producing Staphylococcus aureus. Group B
streptococci produce a substance (CAMP factor) that enlarges the
zone of lysis formed by the staphylococcal beta-hemolysin. |
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capillary fragility test,
capillary resistance test, tourniquet t. (def. 1). |
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captopril test, (for renovascular
hypertension) the angiotensin-converting enzyme
inhibitorcaptopril is administered to a patient with
hypertension. If the patient's plasma renin level increases
sharply within one hour, this indicates that the hypertension
has a renovascular cause such as renal artery stenosis (see
under stenosis). |
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carbohydrate utilization test, any of
several tests for identification of yeasts and certain other
organisms according to a profile of carbohydrate assimilation. |
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carbon monoxide test, see specific tests,
including Preyer t., Rubner t. (def. 1), Salkowski t. (def. 1),
Wetzel t., Zaleski t. |
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card test, a type of laboratory
test that uses nonmicroscopic techniques; tissue or fluid to be
examined is placed on a plastic-coated card with a reagent and
visible reactions such as color changes or agglutination are
noted. |
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Casoni intradermal test, (for hydatid
disease) after injection into the skin of hydatid fluid, if
there is immediate or delayed production of a wheal and flare
reaction, this denotes hydatid infection. The test is now little
used because of low specificity. |
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catalase test, (for the production of
heat-stable catalase by bacteria) a culture is treated with
hydrogen peroxide and heated. The presence of gas bubbles
indicates a positive reaction. Micrococci, staphylococci, most
species of Bacillus, and anaerobic diphtheroids are
catalase-positive; streptococci, pneumococci, and most
Actinomyces are catalase-negative. Catalase quantity and heat
stability are species-dependent; inclusion of the detergent
Tween-80 makes the test semiquantitative. |
|
catoptric test, (for cataract) observations
are done of the reflections from the cornea and the surfaces of
the crystalline lens. |
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CCK test, cholecystokinin t. |
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cellobiose/mannitol test, (for celiac
disease)cellobiose and mannitol are administered and their
relative degrees of absorption are compared. Because of the
relative permeability of the intestine to large molecules like
cellobiose and small ones like mannitol, in celiac disease there
is greater absorption of cellobiose and less absorption of
mannitol. |
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challenge test, challenge (def.
3). |
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chemiluminescence test, a sensitive test of
neutrophil microbicidal function that involves detection of the
chemiluminescent energy emitted by unstable and highly reactive
oxygen metabolites, e.g., singlet oxygen, produced during the
respiratory burst following phagocytosis. It is able to detect
heterozygous carriers of chronic granulomatous disease as well
as homozygotes and also patients with myeloperoxidase
deficiency. |
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Chick-Martin test, a method for determining
the phenol coefficient of disinfectants in water contaminated by
organic matter; serial dilutions of disinfectant are incubated
with a specified quantity of yeast and bacteria for a period of
30 minutes to see how many of the microorganisms have been
killed. |
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Chimani-Moos test, a test for
detecting simulated deafness. |
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chi-square test, any statistical
hypothesis test that employs the chi-square (χ2) distribution
(q.v.), especially two tests applied to categorical data: the
χ2-test of goodness of fit, which tests whether an observed
frequency distribution fits a specified theoretical model, and
the χ2-test of independence or homogeneity, which tests whether
two or more series of frequencies (the rows and columns of a
contingency table) are independent. In both cases the test
statistic is the sum over all categories of the squared
difference between the observed and expected frequencies divided
by the expected frequency, under the null hypothesis. The
sampling distribution of this χ2-statistic approaches the
χ2-distribution as the sample size increases, under the null
hypothesis. |
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cholecystokinin test, (for pancreatic
function)CCK test; after intravenous administration of
cholecystokinin, the resultant pancreatic secretion of amylase,
trypsin, and lipase is measured by collection through a tube in
the duodenum. This test is often combined with the secretin test
and called the secretin-cholecystokinin test. |
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cholesterol test, see specifc tests,
including Liebermann-Burchard t., Salkowski t. (def. 2),
Schultze t. (def. 2). |
|
cis-trans test, in microbial genetics, a
test to determine whether two (recessive) mutations are alleles
(located in the same gene) or pseudoalleles (located in
different genes). A heterozygote carrying the mutations on the
same chromosome (cis configuration) will show a wild-type
phenotype in either case, but one carrying the mutations on
different chromosomes (trans configuration) will show a
wild-type phenotype if they are pseudoalleles and a mutant
phenotype if they are alleles. |
|
citrate test, (for differentiation of
organisms of the Enterobacter group of bacteria) the test
organism is grown on a medium containing citrate as its sole
carbon source (Simmons citrate agar). The metabolism of citrate
(positive reaction) turns the medium from green to blue. The
Enterobacteriaceae are mostly positive; Edwardsiella,
Escherichia, Morganella, Shigella, and Yersinia are negative. |
|
clomiphene citrate challenge test, (for
female factor infertility) the patient's blood levels of
follicle-stimulating hormone are measured on the third day of
her menstrual cycle and she takes clomiphene citrate on days 5
through 9. If her levels of follicle-stimulating hormone are
elevated on day 10, she probably has a diminished ovarian
reserve. |
|
coagulase test, (for coagulase
activity) bacteria are added to citrated or oxalated (human or
rabbit) blood plasma; in the presence of coagulase, the plasma
gels within three hours. Coagulase activity is also demonstrable
by mixing bacteria with blood plasma on a slide; if positive,
clumping occurs, with fibrin formation. |
|
cocaine test, after instillation of a
cocaine solution in each eye, the pupil of an eye affected by
Horner syndrome remains smaller than that of the normal eye. |
|
coccidioidin test, an intracutaneous test
for coccidioidomycosis, using the antigen coccidioidin. Because
most individuals in endemic areas are skin test positive it is
not useful in diagnosis. A negative skin test (cutaneous anergy)
occurs in many patients with disseminated disease and indicates
a poor prognosis. |
|
Cohn test, a test for color perception by
the use of variously colored embroidery patterns. |
|
colchicine test, see Zeisel t. |
|
cold pressor test, immersion of one hand in
ice water for several minutes, causing vasoconstriction,
tachycardia, and transient hypertension; it is used as an
alternative stress test for detection of coronary artery disease
in patients incapable of undergoing an exercise stress test and
as a test of vasomotor function. |
|
collateral circulation test, see specific
tests, including Korotkoff t., Pachon t., and tourniquet t.
(defs. 2, 3). |
|
color perception test, see specific tests,
including Bodal t., Cohn t., Ishihara t., lantern t., Nagel t. |
|
combined anterior pituitary test, a dynamic
test of the functioning of the anterior pituitary, such as after
surgery or radiation to the gland; four exogenous hypothalamic
hormones are administered intravenously (corticotropin-releasing
hormone, growth hormone–releasing hormone, luteinizing
hormone–releasing hormone, and thyrotropin-releasing hormone)
and levels of the corresponding pituitary hormones in the blood
are assessed at intervals for about two hours. |
|
complement fixation test, see
under fixation. |
|
concentration test, (for renal function) the
patient is placed under conditions that cause the normal person
to elaborate urine containing one or more constituents in high
concentration, and the results are observed to see whether the
patient is able to attain this concentration.(for renal tubular
function) water restriction to measure urine concentration as
reflected in specific gravity or osmolality. |
|
conglutinating complement absorption test, a
test resembling the complement fixation test (see under
fixation), using as the indicator of antigen-antibody reaction
the disappearance of conglutinin (q.v.) activity. |
|
Congo red test, (for amyloidosis)
Congo red is injected intravenously; if more than 60 per cent of
the dye disappears after 1 hour, amyloidosis is indicated. |
|
conservative test, a test having a type I
error probability that is at most a stated nominal level. |
|
contact tests, patch t's. |
|
contraction stress test, the monitoring of
the response of the fetal heart rate to uterine contractions by
cardiotocography; uterine contractions may be spontaneous or
induced by maternal nipple stimulation or by intravenous
infusion of oxytocin (oxytocin challenge test). A negative
(normal) test consists of three contractions within a 10-minute
period with no deceleration of the fetal heart rate; a late
deceleration pattern may reflect fetal hypoxia. |
|
Coombs test, antiglobulin t. |
|
copper test, see Schönbein t.
(def. 2). |
|
cover test, see alternate cover t. and
cover-uncover t. |
|
cover-uncover test, a test for determining
the type of phoria, by covering one eye and noting its movement
as it is uncovered. |
|
Crafts test, in organic disease of the
pyramidal tract, stroking with a blunt point upward over the
dorsal surface of the ankle, the leg being extended and the
muscles relaxed, produces a dorsal extension of the great toe
similar to the Babinski reflex. |
|
Crampton test, a test for physical
resistance and condition based on the difference between the
pulse and blood pressure in the recumbent position and in the
standing position. A difference of 75 or more indicates good
condition; one of 65 or less shows a poor condition. |
|
creatinine test, see specific tests,
including Jaffé t. (def. 1), Kerner t., Salkowski t. (def. 4),
Thudichum t., von Maschke t., Weyl t. (def. 1). See also
creatinine, methods for, under method. |
|
Cuignet test, (for simulated unilateral
blindness) the bar-reading test used to detect simulated
unilateral blindness or malingering. |
|
cycle ergometer test, bicycle
ergometer exercise t. |
|
cysteine test, see specific tests, including
nitroprusside t. (def. 1) and Sullivan t. |
|
cystine test, see Liebig t. |
|
cytosine test, see Wheeler and
Johnson t. |
|
dark-adaptation test, (for vitamin A
deficiency) a test based on the fact that with a deficient
intake of vitamin A the ability to see a dimly illuminated
object in a dark room is diminished. |
|
darkroom test, (to determine the tendency to
develop acute angle-closure glaucoma) ocular pressure is
measured by the applanation tonometer, the subject is placed in
a darkroom for one hour, and applanation tonometry is then
repeated. |
|
Davidsohn differential absorption
test, Paul-Bunnell-Davidsohn t. |
|
D-dimer test, see under assay. |
|
dehydrocholate test, (for the speed of blood
circulation) sodium dehydrocholate solution is injected
intravenously; the usual time elapsing until a bitter taste in
the mouth occurs is between 10 and 14 seconds. |
|
Denver Developmental Screening test, a test
for identification of infants and preschool children with
developmental delay. |
|
deoxyribonuclease test, (for the
presence of deoxyribonuclease in bacteria) a nutrient agar plate
containing deoxyribonucleic acid and toluidine blue is
inoculated from a young agar slant; after incubation a red zone
around the inoculum indicates the presence of deoxyribonuclease.
Called also DNase t. |
|
deoxyuridine suppression test, (for folate
or cobalamin deficiency) lack of 5,10-methylene tetrahydrofolate
inhibits incorporation of deoxyuridine into DNA, so that
deoxyuridine fails to inhibit incorporation of
3H-thymidine. |
|
dexamethasone suppression test, high-dose,
(for Cushing syndrome) urinary levels of cortisol and
17-hydroxycorticosteroid are measured following administration
of dexamethasone at 16 times the level used in replacement
therapy; cortisol secretion is suppressed in patients with
Cushing syndrome but not in those with ectopic ACTH syndrome or
adrenal tumors. |
|
dexamethasone suppression test, low-dose,
(for Cushing syndrome) urinary levels of cortisol and
17-hydroxycorticosteroid are measured following administration
of dexamethasone at three to four times the level used in
replacement therapy; cortisol secretion is suppressed in normal
patients but not in those with Cushing syndrome. |
|
dextrose test, glucose t. |
|
DFA-TP test, direct fluorescent
antibody–Treponema pallidum t. |
|
diabetes test, any of various tests for
diabetes mellitus; see glucose t. and glucose tolerance t. |
|
diacetyl test, (for urea) the solution to be
tested is mixed with concentrated hydrochloric acid and diacetyl
monoxime, a more stable precursor of diacetyl; condensation of
diacetyl and urea forms the yellow chromogen diazine,
particularly at an elevated temperature (usually 45 0C). |
|
Dick test, (for susceptibility to scarlet
fever) purified erythrogenic toxin from group A streptococci is
injected intradermally; appearance within 24 to 48 hours of a
small area of reddening of the skin indicates susceptibility of
the subject. |
|
differential test for infectious
mononucleosis, Paul-Bunnell-Davidsohn t. |
|
dilution test, see under method. |
|
dimethylglyoxime test, (for nickel) the
object or substance being tested is placed in a solution of
dimethylglyoxime; if nickel is present, the solution will turn
brown. |
|
diphtheria test, see Schick t. |
|
direct antiglobulin test, direct
Coombs test, see antiglobulin t. |
|
direct fluorescent antibody–Treponema pallidum test,
DFA-TP test; a serologic test for syphilis
that uses direct immunofluorescence. |
|
disk diffusion test, a type of
antimicrobial susceptibility test in which agar plates are
inoculated with a standardized suspension of a microorganism and
then antibiotic-containing disks are applied to the agar
surface. Following overnight incubation, the diameters of the
zones of inhibition or clearing surrounding the disks are
measured to calculate how susceptible or resistant the
microorganism is. |
|
DNase test, deoxyribonuclease t. |
|
Dolman test, (for ocular dominance) the
patient holds in both hands a card with a hole in it through
which to look at a light. |
|
Donath-Landsteiner test, (for paroxysmal
cold hemoglobinuria) a test based on the fact that the blood of
patients with this disease contains complement-dependent iso-
and autohemolysin (Donath-Landsteiner antibody) which unites
with red cells only at low temperatures (20 to 100C), hemolysis
occurring only after warming to 370C. |
|
double glucagon test, (for deficiency of
amylo-1-6-glucosidase) glucagon is administered after a 12-hour
fast and again shortly after a meal; if the blood sugar fails to
rise after the first administration but has a normal rise after
the second, the test is positive. |
|
Draw-a-Person test, a commonly
used projective test for assessing personality style and
psychopathology by interpretation of a drawing of a person done
by the subject, based on the assumption that their personality
characteristics will be introjected onto the drawing. |
|
drawer tests, (for integrity of cruciate
ligaments of knee) the knee is flexed to a 900 angle; at the
femoral-tibial junction, if the tibia can be drawn too far
forward there is rupture of the anterior ligaments (anterior
drawer t.) and if it can be drawn too far back there is rupture
of the posterior ligaments (posterior drawer t.). Called also
drawer signs. |
|
drinking test, (for glaucoma) one liter of
water is ingested as rapidly as possible into an empty stomach.
The intraocular pressure is measured every 15 minutes; a rise of
8 to 15 mm Hg in less than 30 minutes indicates glaucoma. Called
also water provocative t. |
|
Duane test, one using a candle
flame and prisms to measure the degree of ocular heterophoria. |
|
Dugas test, (for diagnosis of
dislocation of the shoulder) place the hand of the affected side
on the opposite shoulder and bring the elbow to the side of the
chest; if this cannot be accomplished (Dugas sign), dislocation
of the shoulder exists. |
|
Duke test, a type of bleeding
time test in which the incision is made in the earlobe. |
|
dye exclusion test, the determination of
cell viability in vitro. Following exposure of a cell
preparation to trypan blue or eosin, dead cells take up the dye
from the medium whereas living cells remain unstained. |
|
dynamic test, one designed to test some
physiologic process in the body, such as a challenge, a
stimulation test, or a suppression test. |
|
E test, a variation of the dilution method
for testing antimicrobial susceptibility. A plastic strip is
used that has a defined concentration of drug on one side and an
interpretive scale of minimal inhibitory concentrations on the
other side; it is put on the surface of an agar medium
inoculated with the microorganism to be tested. This method is
most useful for fastidious bacteria such as Streptococcus
pneumoniae, Haemophilus influenzae, and certain anaerobic
bacteria. |
|
early pregnancy test, a do-it-yourself
immunologic test for pregnancy performed in the home as early as
one day after menstruation was expected (missed period); a
variety of tests exist, all based on an increase in urinary
levels of human chorionic gonadotropin after fertilization. |
|
ECG stress tests, stress t's. |
|
Ehrlich test, Ehrlich diazo
reaction; see under reaction. |
|
Elek test, toxigenicity t. |
|
Elsberg test, (for sense of
smell) variations in function of the sense of smell, or in rate
of fatigue, may be used to distinguish between intracerebral and
extracerebral tumors or other lesions. |
|
Ely test, (for contracture) with the patient
prone, if flexion of the leg on the thigh causes the buttocks to
arch away from the table and the leg to abduct at the hip joint,
there is contracture of the lateral fascia of the thigh. |
|
EP test, erythrocyte
protoporphyrin t. |
|
Erhard test, a test for detecting
simulated deafness. |
|
Erichsen test, see under sign. |
|
erythrocyte protoporphyrin test, (for lead
poisoning)EP test; a screening test in which erythrocyte
protoporphyrin levels are determined by direct fluorometry of
whole blood or fluorescence analysis of whole blood extracts;
levels are increased in lead poisoning and iron deficiency. |
|
esophageal acid perfusion test,
Bernstein t. |
|
euglobulin lysis test, (for hemorrhagic
tendencies) the time of fibrinolysis is measured by determining
the time required to dissolve an incubated clot composed of
precipitated plasma euglobulin and exogenous thrombin. Lysis in
less than 90 minutes indicates abnormally enhanced fibrinolytic
activity. |
|
exact test, a statistical test based on the
actual probability distribution of the data in the study, rather
than on an approximation of it. |
|
exercise tests, exercise stress tests, any
of various stress tests in which exercise is used in the
electrocardiographic assessment of cardiovascular health and
function, particularly in the diagnosis of myocardial ischemia.
The most widely used forms are the treadmill and bicycle
ergometer exercise tests; they are usually graded, consisting of
a series of incrementally increasing work loads sustained for
defined intervals. |
|
F-test, a statistical test comparing the
means of more than two groups simultaneously by comparing two
different measures of variance of the observations. One
statistic measures the variations between the means of the
groups (the between-groups variation), the other the variations
within the groups (the within-group variation). If the two
measures of variance yield similar results and their ratio, the
F-ratio, approximates 1.0, the null hypothesis that all
observations came from the same population cannot be rejected,
whereas under the alternative hypothesis, the F-ratio is
expected to be larger than 1.0. The test is the first step in
the analysis of variance (ANOVA). |
|
FAB test, fluorescent antibody t. |
|
Farber test, presence of swallowed vernix
cells in the meconium of a newborn baby indicates partial
intestinal stenosis; their absence indicates intestinal atresia. |
|
Farr test, (a radioimmunoassay for measuring
absolute amounts of antibody) antibody is reacted with
radiolabeled antigen and precipitated with ammonium sulfate;
bound antigen or hapten is precipitated while free antigen
remains in solution. This test is based on the capacity of
antibody to combine with antigen rather than on such secondary
properties as precipitation and therefore measures all
immunoglobulin classes and subclasses. |
|
FeNa test, excreted fraction of filtered
sodium test, a measure of renal tubular reabsorption of sodium,
calculated as follows: |
|
(U/P)Na |
|
(U/P)Cr |
|
where U and P represent concentrations of sodium and creatinine
in urine and plasma, respectively. |
|
femoral nerve stretch test, (for lesions of
third or fourth lumbar disk) passive knee flexion in the prone
position causes pain in the back or thighs. |
|
fermentation test, (for glucose
and other sugars in urine) boil a specimen to destroy bacteria,
then add baker's yeast and incubate; perform Benedict test for
reducing sugars on this specimen and an unfermented specimen.
Glucose, fructose, and maltose are fermented and give a reaction
in the unfermented specimen but not in the fermented specimen. |
|
fern test, see ferning. |
|
ferric chloride test, ferric chloride in
acidic solution is added to a urine specimen; many substances
are oxidized giving colored products. Positive reactions are
given by melanin, acetoacetic acid, bilirubin, phenothiazines,
salicylates, and the keto acids present in phenylketonuria,
alkaptonuria, maple syrup urine disease, and oasthouse urine
disease. |
|
fetal acoustic stimulation test, (for
assessing fetal health) a vibroacoustic stimulus such as an
electronic artificial larynx is applied either externally or
directly to the fetus and resultant fetal movements,
cardioacceleration, and alterations in respiration are
evaluated. |
|
FIGLU excretion test, histidine
loading t. |
|
finger-to-finger test, similar to
finger-nose test, for testing coordinated movements of the
extremities. |
|
finger-nose test, finger-to-nose test, (for
coordinated movements of the upper limbs) with arm extended to
one side the patient is asked to slowly try to touch an index
finger to the end of the nose. |
|
Finn chamber test, a type of patch test in
which the materials being tested are held in shallow aluminum
cups (Finn chambers) that are taped against the skin, usually
for several days. |
|
Fishberg concentration test, (a test of
kidney function) the patient's evening meal includes not more
than 200 mL of fluid, and nothing else is consumed before
morning. Urine voided during the night is discarded. The morning
urine is saved, the patient kept in bed, and the urine of 1 hour
later and 2 hours later is saved. If the specific gravity of any
of these 3 specimens is less than 1.024 there is impairment of
renal concentration. |
|
Fisher exact test, a statistical hypothesis
test of independence of rows and columns in a 2 × 2 contingency
table based on the exact sampling distribution of the observed
frequencies, useful when any expected value in the table is
small. |
|
fistula test, the air in the external
auditory canal is compressed or rarefied: if there is erosion of
the inner osseous wall of the tympanum exposing the membranous
labyrinth, nystagmus will be produced, provided the labyrinth
still functions. |
|
Flack test, (of physical efficiency) after a
full inhalation the subject blows as long as possible into a
mercury manometer with a force of 40 mm mercury. |
|
flocculation test, any serologic test in
which a flocculent agglomerate is formed; usually referring to a
variant form of the precipitin reaction, and sometimes to types
of agglutination tests. |
|
fluorescein dilaurate test,
pancreolauryl t. |
|
fluorescent antibody test, FAB
test; a test for the distribution of cells expressing a specific
protein by binding antibody specific for the protein and
detecting complexes by fluorescent labeling of the antibody; if
it is combined with cell sorting, determinations can be
quantitative. |
|
fluorescent treponemal antibody absorption test,
FTA-ABS test; the standard treponemal
antigen serologic test for syphilis; patient serum is diluted
with an extract of other treponemes to remove nonspecific
antibodies, then reacted with a strain of Treponema pallidum
fixed to a glass slide; specific antibodies adhering to the
treponemes are demonstrated with fluorescein-labeled antihuman
globulin. Positive tests are seen in about 85 per cent of cases
of primary syphilis, 100 per cent of secondary syphilis, and 98
per cent of late syphilis. |
|
food challenge test, food
challenge. |
|
formaldehyde test, see specific tests,
including Jorissen t. and Kentmann t. |
|
Fouchet test, (for bilirubin in urine) a few
drops of Fouchet reagent are added to the specimen; a green
color is produced if bilirubin is present. |
|
Fournier test, (for ataxic gait) the patient
is asked to rise on command from a sitting position, then to
rise and walk, to stop quickly on command, and then to walk and
turn around quickly on command. The ataxic gait is thus brought
out. |
|
Francis test, (for bile acids in urine) in a
test tube is placed 2 g of glucose in 15 g of sulfuric acid and
the urine is placed on top of this; a purple color forms if bile
acids are present.an intracutaneous test in pneumonia for
ascertaining the body response to the infection and whether the
specific antibodies are present after treatment with
antipneumococcus serum. The homologous pneumococcus
polysaccharide is used in the skin test. |
|
Fränkel test, examination of the nasal
cavity with the patient's head bent down between the knees and
rotated so that the side to be examined is turned upward. If pus
is seen in the middle meatus, suppuration in some of the
anterior accessory sinuses is indicated. |
|
Friberg test, tray agglutination
t. |
|
Friderichsen test, (for vitamin A
deficiency) determination of the weakest light stimulus which
will give rise to an oculomotor reflex. A variation from normal
indicates vitamin A deficiency. |
|
fructosamine test, determination
of the serum fructosamine level by measurement of the reduction
of nitroblue tetrazolium to purple under alkaline conditions; it
is used as an index of the average glycemic state over the
preceding two to three weeks. |
|
fructose test, see Rubner t. (def. 2) and
Selivanoff t. |
|
fructose tolerance test, (for
liver function) a large quantity of fructose is administered and
the power of the liver to absorb it is monitored. |
|
FTA-ABS test, fluorescent
treponemal antibody absorption t. |
|
fundus reflex test, retinoscopy. |
|
Funkenstein test, an index of central
autonomic reactivity, consisting of observing the response in
systolic blood pressure after intramuscular injection of 10 mg
of acetylcholine. |
|
Gaenslen test, see under sign. |
|
galactose breath test, a breath test of
liver function: the fasting subject is administered a dose of
galactose labeled with carbon 13 and levels of labeled carbon
dioxide in the breath are measured at specific time intervals.
Low levels of carbon dioxide indicate that the galactose is not
being metabolized properly, indicating either an enzyme
deficiency or liver dysfunction such as the fibrosis
accompanying hepatitis. |
|
galactose tolerance test, a laboratory test
done to determine the liver's ability to convert galactose into
glycogen. Two methods may be used; the oral method, which
requires about 5 hours to complete, and the intravenous method,
which requires about 2 hours and is more accurate. With the oral
method, elimination of more than 3 g of galactose in the urine
during a 5-hour period indicates liver damage. With the
intravenous method, all galactose should have been eliminated
from the blood 45 minutes after its injection. |
|
gastric function test, see specific tests,
such as augmented histamine t. and pentagastrin t. Abnormal
results on the Schilling test may indicate defective gastric
secretion of intrinsic factor. |
|
Gault test, (for simulated deafness) the
patient's good ear is closed and a sound is made near the
supposed bad ear; winking on the tested side indicates hearing. |
|
gaze test, (for ocular and vestibular
functioning) movements of the eye are recorded with the patient
gazing straight at an object and at positions off to different
sides of it; then with eyes closed for 20 seconds, the patient
must perform a small mental exercise. The eyes normally should
assume a center gaze while they are closed. |
|
gelatin agglutination test, a sperm
agglutination test in which the sperm and serum are put in a
gelatin solution. Called also Kibrick t. |
|
gel diffusion test, see
immunodiffusion. |
|
Gerhardt test, (for acetoacetic acid in the
urine) filter, in order to remove the phosphates, and add a few
drops of a solution of ferric chloride, which produces a deep
red color, which disappears when sulfuric acid is added.(for
bile pigments in the urine) shake urine with an equal measure of
chloroform and then add iodine tincture and potassium hydroxide
to the separated chloroform; a yellow or yellowish brown color
is produced (Charles Frédéric Gerhardt). |
|
germ tube test, (for Candida albicans) an
inoculum of Candida is incubated in serum for 2 to 3 hours at
370C; formation of germ tubes is a positive result. |
|
Gibbon and Landis test, (for peripheral
circulation) a pair of extremities (the hands, if the feet are
to be tested; the feet, if the hands are to be tested) are
immersed in a bath of 430–450C. If the temperature in the
unimmersed extremities rises, the circulation is normal. |
|
Gies biuret test, (for proteins) a form of
biuret test employing the following reagent: mix 25 mL of a 3
per cent solution of cupric sulfate and 975 mL of a 10 per cent
solution of potassium hydroxide. |
|
glucagon stimulation test, (for deficiency
of growth hormone) blood samples are taken before and at
intervals of 1, 2, 2.5, and 3 hours after subcutaneous or
intramuscular injection of glucagon; radioimmunoassay of the
serum is then done by enzyme partition. |
|
glucose test, any of various laboratory
tests for glucose in the urine; many formerly common ones are no
longer used. See Benedict t., Rubner t., and saccharimeter t. |
|
glucose tolerance test, a
metabolic test of carbohydrate tolerance, measuring active
insulin, a hepatic function based on the power of the normal
liver to absorb and store large quantities of glucose, and the
effectiveness of intestinal absorption of glucose. The most
common method is the oral glucose tolerance test (q.v.). |
|
glucose tolerance test, oral, the most
common kind of glucose tolerance test. Glucose is ingested into
a fasting stomach and measurements of plasma glucose are taken
over time; if glucose levels do not return to normal within 2 to
2.5 hours the patient may have impaired glucose tolerance or
diabetes mellitus. |
|
glycosylated hemoglobin test, measurement of
the percentage of hemoglobin A molecules that have formed a
stable keto–amine linkage between the terminal amino acid
position of the β-chains and a glucose group; in normal persons
this amounts to about 7 per cent of the total, in diabetics
about 14.5 per cent. Used in the management of patients with
diabetes mellitus. |
|
Gmelin test, (for bile pigments) fuming
nitric acid is so added to the suspected urine that it forms a
layer under it. Near the junction of the two liquids, rings are
formed—a green ring above, and under it a blue, violet-red, and
reddish yellow. If the green and violet-red rings are absent,
the reaction shows the probable presence of lutein. |
|
Goodenough draw-a-man test, Goodenough draw-a-person test,
(for intelligence) the general intelligence
of the child is assessed by asking him or her to draw a picture
of a man as well as possible. |
|
Goodenough-Harris drawing test, a revision
of the Goodenough draw-a-man test, in which scoring emphasizes
the presence or absence of body and clothing detail rather than
artistic skill. |
|
graded exercise tests, see
exercise t's. |
|
Graefe test, (for heterophoria) on holding a
prism of 10 degrees before one eye, base up or down, two images
are formed; one of these images is displaced laterally in
heterophoria. |
|
Graham test, the intravenous or oral
administration of iodophthalein sodium prior to radiographic
examination of the gallbladder. |
|
Griess test, a formerly common test for
nitrate-reducing bacteria in a fluid, done by adding sulfuric
acid and an indicator to a dilute solution and watching for a
color change. The same name is now applied to nitrite tests for
bacteriuria in which a urine specimen collected when the patient
wakes in the morning is tested for nitrites using a special tape
or dipstick. |
|
Grigg test, (for proteins) metaphosphoric
acid precipitates all proteins except the peptones. |
|
group test, a test of intelligence or
aptitude given to a number of persons at one time. |
|
guaiac test, (for occult blood)
glacial acetic acid and a solution of gum guaiac are mixed with
the specimen; on addition of hydrogen peroxide, the presence of
blood is indicated by a blue tint. |
|
Guerreiro-Machado test,
Machado-Guerreiro t. |
|
Guthrie test, (for phenylketonuria) blood
from an infant suspected of having abnormally high levels of
phenylalanine is placed on filter paper, which is then put on an
agar plate with a strain of Bacillus subtilis that requires
phenylalanine for growth. In the presence of blood containing
phenylalanine, a halo will form around the filter paper. |
|
Gutzeit test, (for arsenic) a paper is
moistened with an acidulated silver nitrate solution and exposed
to the fumes from the suspected liquid, which is mixed with zinc
and dilute sulfuric acid. The formation of a yellow spot on the
paper indicates the presence of inorganic arsenic compounds. |
|
Haagensen test, observation of the contour
of the breasts when the patient leans forward as a means of
detecting malignant changes. |
|
HAI test, hemagglutination
inhibition t. |
|
Hallion test, Tuffier t. |
|
Ham test, acidified serum t. |
|
Hamilton test, when the shoulder joint is
luxated, a rule or straight rod applied to the humerus can be
made to touch the outer condyle and the acromion at the same
time. |
|
hapten inhibition test, serologic
characterization of an antigenic determinant by employing known
haptens to mask the antigen binding site of antibody specific
for it. |
|
harmonic acceleration test, (for
vestibuloocular reflex) rotation of a patient seated in a chair
in complete darkness, with monitoring of eye movements; with
normal vestibuloocular reflexes the eyes will undergo rotatory
nystagmus to the same degree in both eyes in the direction
opposite to that of the rotation. |
|
Harrison spot test, (for bilirubin in urine)
add to 10 mL of urine 5 mL of a 10 per cent solution of barium
chloride, mix, and filter. Spread filter paper on dry filter
paper. Add one to two drops of Fouchet reagent (trichloroacetic
acid 25 g, water 100 mL, and 10 per cent solution of ferric
chloride 10 mL); a positive reaction gives a blue to green
color. |
|
hatching test, (for
schistosomiasis) live schistosome eggs in urine or feces can be
detected when they hatch to produce miracidia when placed in
water; the miracidia are attracted to light and can readily be
identified. |
|
Heaf test, a type of
intracutaneous tuberculin test; needle points of a
multiple-puncture apparatus are dipped into 1 to 2 drops of
tuberculin PPD, then placed on the forearm and made to penetrate
the skin to a depth of 1 mm, depositing tuberculin in the outer
layer of the skin. In three to seven days, a positive reaction
is palpable, coalescing induration (edema) extending more than 5
mm around the puncture wounds. |
|
heel-knee test, heel-shin test, (for
coordinated movements of the lower limbs) the patient, lying
supine, is asked to touch the knee on one side with the opposite
heel and then to pass the heel slowly down the front of the shin
to the ankle. Called also heel-to-knee or heel-to-shin t. |
|
heel-tap test, see under reflex. |
|
heel-to-knee test, heel-to-shin
test, heel-knee t. |
|
hemadsorption test, an in vitro test for
detecting hemagglutinating viruses based on the adherence of red
blood cells to cells of the infected tissue in the presence of
hemagglutinin. |
|
hemagglutination inhibition (HI, HAI) test,
a highly sensitive procedure for the measurement of soluble
antigens in biologic specimens in which the specimen is first
incubated with homologous antibody and then incubated with
antigen-coated red cells; the amount of hemagglutination
reflects the amount of free antibody present after reaction with
the specimen and thus varies inversely with the amount of
antigen in the specimen.a procedure for the measurement of serum
antibodies directed against a hemagglutinating virus; the
highest dilution of serum that completely inhibits
hemagglutination by a standardized viral preparation is reported
as the hemagglutination titer. |
|
hemosiderin test, see specific tests,
including Perls t. and Rous t. |
|
Henshaw test, a test to aid in
the selection of the appropriate homeopathic remedy in a given
case of disease. A visible flocculation zone develops in the
patient's blood serum when it is brought into contact with a
potentized remedy homeopathically indicated in the case. |
|
hepatic function test, liver
function t. |
|
Hering test, (for binocular versus monocular
vision) the subject looks with both eyes through a tube
blackened within and having a thread running vertically across
the farther end. A small round body is placed either before or
behind the thread. If vision is binocular, the subject can
immediately tell whether the ball is nearer than the thread or
farther away; if vision is monocular, this distinction cannot be
made. |
|
Hess capillary test, tourniquet
t. (def. 1). |
|
heterophil antibody test, heterophile antibody test,
any of several tests for heterophile
antibodies associated with infectious mononucleosis; the most
common ones are the monospot test and the Paul-Bunnell-Davidsohn
test. |
|
HI test, hemagglutination
inhibition t. |
|
Hickey-Hare test, (for diabetes insipidus)
intravenous infusion of hypertonic saline after establishment of
water diuresis induces antidiuresis in normal subjects but not
in patients with diabetes insipidus. |
|
Hines and Brown test, cold
pressor t. |
|
histamine test, histamine flare t.any of
several formerly common gastric function tests in which
histamine was injected to stimulate gastric secretion and
measure output of gastric acid; see also augmented histamine
test.a formerly used test for presence of a pheochromocytoma;
persons with such a tumor would show first a fall and then a
marked rise in blood pressure. |
|
histamine flare test, (for leprosy and
postherpetic neuralgia) a drop of 1:1000 histamine acid
phosphate solution is placed on the skin and a needle puncture
is made through it; the test is positive if there is no erythema
flare when the puncture is made within the suspected lesion
area, or if the flare stops at the border of the lesion when it
is made slightly to the outside of it. |
|
histidine loading test, (for
folic acid deficiency) a loading dose of histidine is given, and
the resultant urinary excretion of excess formiminoglutamic acid
(FIGLU), secondary to decreased amounts of tetrahydrofolic acid,
is measured. Called also FIGLU excretion t. |
|
Hitzig test, (for vestibular apparatus) the
positive electrode of a galvanic current is applied just in
front of the ear being examined while the negative electrode is
held in the patient's hand, the patient standing with feet
together and eyes closed. A current of 5 milliamperes causes a
leaning toward the positive pole in normal persons. |
|
hock test, spavin t. |
|
Hoffmann test, (for tyrosine) add mercuric
nitrate to the suspected liquid and boil it; then add nitric
acid with a little nitrous acid. A red color is produced if
tyrosine is present, and a red precipitate is seen. |
|
Hofmeister test, (for leucine) warm the
suspected liquid with mercurous nitrate; if leucine is present,
metallic mercury is deposited.(for peptones) mix phosphotungstic
and hydrochloric acids; let the mixture stand twenty-four hours,
and filter. With this reagent a solution containing peptones
with no albumin will afford a precipitate. |
|
Hoppe-Seyler test, (for carbon monoxide in
the blood) add to blood twice its volume of a solution of sodium
hydroxide of 1.3 specific gravity: normal blood will form a
dingy brown mass with a green shade if spread thin on a white
surface; but if carbon monoxide is present, the mass is red, and
so is the thin layer.(for xanthine) add the substance to be
tested to a mixture of chlorinated lime in a porcelain dish; a
dark-green ring is formed at first. |
|
horse cell test, monospot t. |
|
Hotis test, (for mastitis in cows) fresh
milk containing bromcresol purple is incubated for 24 hours; a
positive reaction is the formation of yellow flakes on the sides
of the test tube. |
|
Huddleson test, an agglutination test for
human brucellosis. |
|
Huhner test, postcoital t. |
|
hydrogen breath test, (for deficiency of
lactase or other hydrolases, or colonic overgrowth of bacteria)
a known quantity of carbohydrate is administered and the
subject's exhalations are trapped and measured at timed
intervals; patients unable to digest or absorb carbohydrates in
the small intestine will have excess carbohydrates in the colon
being broken down there by bacterial fermentation, causing an
increase of blood hydrogen and thus of hydrogen exhaled by the
lungs. |
|
hydrogen peroxide test, (for blood) a 20 per
cent solution of hydrogen peroxide is added to the suspected
fluid; if blood is present even in minute proportion, bubbles
will rise, forming foam on the surface of the fluid. |
|
hydrostatic test, floating of the
lungs of a dead infant when placed in water indicates that the
child was born alive; called also Raygat t. |
|
hyperemia test, Moschcowitz t. |
|
hyperventilation test, (for Prinzmetal
angina) the patient hyperventilates (breathes rapidly and
deeply) for five minutes and an electrocardiogram is recorded
before, during, and for ten minutes after this. Abnormal
coronary vasoconstriction, demonstrated by ST segment changes,
indicates Prinzmetal angina. |
|
hypochlorite-orcinol test, (for glycerol) to
3 mL of the unknown add 3 drops of N/1 sodium hypochlorite
solution and boil one minute to drive off chlorine. Then add an
equal volume of strong hydrochloric acid and a little orcinol.
Boil, and a violet or greenish blue color indicates glycerol or
a sugar, or some substance that can be oxidized to a sugar. |
|
hypo-osmotic swelling test, (for viability
of sperm) a sperm sample is put into a hypo-osmotic solution;
spermatozoa with normal plasma membranes should undergo swelling
and curling of their tails. If less than 50 per cent of the
spermatozoa show this change, the sample is abnormal. |
|
hypothesis test, an abstract procedure for
determining whether a set of observations is consistent with a
hypothesis under consideration; it is the theoretical basis of
most statistical tests. A hypothesis test decides between two
hypotheses, one stating that the effect under investigation does
not exist (the null hypothesis, H0), and the other that some
specified effect does exist (the alternative hypothesis, Ha or
H1), based on the observed value of a test statistic whose
sampling distribution is completely determined by H0. When the
test statistic falls in a set of values known as the critical
region, H0 is rejected. The level of probability of incorrectly
rejecting H0 may be set before the data are collected, usually
at 0.05 or 0.01; this is called the significance level or α
level. It is now more common to report the smallest α at which
the null hypothesis can be rejected; this is called the
significance probability or P value. |
|
hypoxanthine test, see Kossel t. |
|
IFA test, indirect fluorescent antibody
test; see immunofluorescence. |
|
immobilization test, detection of antibody
based on its ability to inhibit the motility of a bacterial cell
or protozoon. |
|
IMViC test, a series of metabolic tests used
as standard procedure to differentiate genera of the
Enterobacteriaceae. See also the individual tests. |
|
indican test, see specific tests, including
Jaffe t. (def. 2) and Weber t. (def. 2). |
|
indirect antiglobulin test,
indirect Coombs' test, see antiglobulin t. |
|
indirect fluorescent antibody
test, see immunofluorescence. |
|
indole test, see specific tests, including
Nencki t., nitroso-indole-nitrate t., pine wood t., and
Salkowski t. (def. 3). |
|
inhalational challenge test, see
under challenge. |
|
inkblot test, Rorschach t. |
|
insulin sensitivity test, (to differentiate
diabetes mellitus from pituitary and adrenal diabetes) a test
dose of exogenous insulin will produce a rapid and marked
decrease in blood glucose levels if the pancreas is not
secreting enough insulin. A much less dramatic response is
produced if hyperglycemia is due to excessive secretion of
either anterior pituitary or adrenocortical hormones. |
|
intelligence test, a set of problems or
tasks posed to assess an individual's innate ability to judge,
comprehend, and reason. |
|
intracutaneous test, intradermal
t. |
|
intradermal test, a skin test in which the
antigen is injected below the skin. Called also intracutaneous
t. |
|
intradermal tuberculin test, a tuberculin
test in which tuberculin is injected below the skin; see
specific tests, including Heaf t., Mantoux t., and tine t. |
|
intravenous secretin test,
secretin t. |
|
inulin clearance test, see under
clearance. |
|
iodine test, (for starch) when a compound
solution of iodine is added to starch, and especially to an acid
or neutral solution of cooked starch paste, a deep-blue color is
produced that disappears on heating and reappears on cooling.
Erythrodextrin and glycogen give a red color with iodine. |
|
Iowa pressure articulation test, a test of
the ability to produce the consonant sounds in isolated words,
particularly the pressure sounds. |
|
irresistible impulse test, see
under impulse. |
|
ischemic forearm test, (for metabolic
myopathies) blood flow in the forearm is impeded using a blood
pressure cuff, blocking oxidative phosphorylation and causing
dependence on anaerobic processes; normal subjects will show
rises in ammonia, lactate, and pyruvate, whereas those with
metabolic myopathies will not. |
|
Ishihara test, (for color vision)
a vision test making use of a series of pseudoisochromatic
plates. |
|
Isojima test, sperm
immobilization t. |
|
isopropanol precipitation test,
(for unstable hemoglobins) a drop of blood is mixed with the
nonpolar solvent isopropanol; most unstable hemoglobins
precipitate more readily than other hemoglobins. Addition of
potassium cyanide reduces false-positive results. |
|
Ivy test, a bleeding time test in which
incisions are made on the forearm, a sphygmomanometer is
inflated around the upper arm, and the time until cessation of
bleeding is recorded. Called also Ivy method. |
|
Jacquemin test, (for phenol) add to the
suspected liquid an equal quantity of aniline and some sodium
hypochlorite in solution; a blue color is produced. |
|
Jaffe test, (for creatinine) to the liquid
add trinitrophenol and then make alkaline with sodium hydroxide.
A red color indicates presence of creatinine.(for indican) to
the suspected liquid are added an equal amount of concentrated
hydrochloric acid, 1 mL of chloroform, and a few drops of a
strong solution of chlorinated soda. The chloroform is colored
blue if indican is present. |
|
Janet test, (for differentiating between
functional and organic anesthesia) the patient is instructed to
say “yes” or “no,” according to whether the examiner's touch is
felt. The patient may say “no” in functional anesthesia, but
will say nothing in cases of organic anesthesia. |
|
Jorissen test, (for formaldehyde) add 0.5 mL
of a 1 per cent solution of phloroglucin in 10 per cent sodium
hydroxide to 1 mL of the urine; a bright red color indicates
free formaldehyde. |
|
Kato test, (for estimation of worm burden) a
standard 50-mg sample of fresh feces is collected, cleared with
glycerine, and examined for worms. |
|
Kentmann test, (for formaldehyde) dissolve
in a test tube 0.1 g of morphine in 1 mL of sulfuric acid; add,
without mixing, an equal volume of the liquid to be tested; in a
short time the latter will take on a reddish violet color if any
formaldehyde is present. |
|
Kerner test, (for creatinine) acidify the
suspected solution and add phosphomolybdic or phosphotungstic
acid in solution; if creatinine is present, it will form a
crystalline precipitate. |
|
Kibrick test, gelatin
agglutination t. |
|
kidney function test, a test of kidney
function, such as of renal clearance or of the glomerular
filtration rate; see also specific tests, including Fishberg
concentration t., radioisotope renal excretion t., Rehberg t.,
and d-xylose absorption t. Called also renal function t. |
|
King-Devick test, (for evaluation
of saccade) the patient looks at a series of charts of numbers
that become progressively harder to read, arranged in a flowing
manner with increasing space between the numbers. Both errors in
reading and speed of reading are included in deriving a score. |
|
Kjeldahl test, (for nitrogen) see
under method. |
|
Kleihauer test, Kleihauer-Betke
test, acid elution t. |
|
Knott test, (for microfilariae or worm
larvae in blood) a blood sample is subjected to lysis in a
dilute (2 per cent) formalin solution, followed by
centrifugation and examination of the stained sediment for
microfilariae or larvae. |
|
Kober test, (for estrogens) when estrogens
are treated with a mixture of sulfuric acid and phenolsulfonic
acid and then diluted with water, a clear pink color is formed;
suitable for qualitative analysis. |
|
Kolmogorov-Smirnov test, a statistical test
of goodness of fit of a sample to a specified theoretical
distribution function, based on the size of the maximum
difference between the cumulative distribution functions of the
sample and theoretical distributions and using the exact
sampling distribution of this difference to determine the
significance level. The test can also be used to determine
whether two samples are drawn from the same population by
examining the maximum difference between the cumulative
distribution functions of the two samples. |
|
Korotkoff test, (for collateral circulation)
in aneurysm, if the blood pressure in the peripheral circulation
remains fairly high while the artery above the aneurysm is
compressed, the collateral circulation is good. |
|
Kossel test, (for hypoxanthine) the liquid
to be tested is treated with zinc and hydrochloric acid and with
sodium hydroxide in excess; if hypoxanthine is present, a
ruby-red color is produced. |
|
Kremer test, SCMC t. |
|
Kruskal-Wallis test, a nonparametric test
for ordinal data, comparing three or more groups simultaneously:
all data are ranked numerically and then the rank values are
summed and averaged for each group. If the null hypothesis that
all groups are drawn from the same population is true, then the
mean ranks should be similar across all groups. |
|
Kuhlmann test, a modification of
the Binet test of intelligence for use in infants. |
|
Külz test, (for β-hydroxybutyric acid) the
fermented urine is evaporated to a syrupy consistency, strong
sulfuric acid in equal volume is added, and the mixture is
distilled. If hydroxybutyric acid is present, α-crotonic acid
will be formed, which will crystallize. If, after fermentation,
the urine shows dextrorotatory properties, β-hydroxybutyric acid
is present. |
|
Kveim test, (for sarcoidosis) a skin test
using antigen from human sarcoid tissue injected intradermally;
any palpable nodule developing at the inoculation site within 6
weeks is biopsied, and histopathologic evidence of epithelioid
cell granulomas constitutes a positive reaction. The test is
positive in about 60 to 80 per cent of patients. |
|
Lachman test, an anterior drawer
test for cases of severe knee injury, performed at 20 degrees of
flexion. |
|
Lancefield precipitation test, a
ring precipitation test for identification and classification of
streptococci. Group-specific antibody reacts in vitro with
group-specific polysaccharide to produce a ring of precipitation
where the two reagents react at the interface. |
|
Lang test, (for taurine) the solution to be
tested is boiled with freshly prepared mercuric oxide; taurine
will cause a white precipitate to appear. |
|
Lange test, (for acetone in urine) 15 mL of
urine are mixed with 0.5 to 1 mL of acetic acid, and a few drops
of a freshly prepared concentrated solution of sodium
nitroprusside added. The mixture is overlaid with ammonia. At
the point of junction a characteristic violet ring is formed. |
|
lateral pivot shift test, (for integrity of
the anterior cruciate ligament) the patient lies prone with the
hip flexed and the knee extended; the examiner gradually flexes
the knee while pushing the outside of the knee medially and
internally rotating the tibia. A thud or jerk at 300–400 of
flexion indicates deficiency of the anterior cruciate ligament. |
|
lantern test, (for color vision) a set of
specially devised lanterns are used to test the patient's color
vision. |
|
latex agglutination test, latex
fixation test, (for presence of antibody) a type of
agglutination test in which antigen to a given antibody is
adsorbed to latex particles and mixed with a solution to observe
for agglutination of the latex. |
|
Lee test, (for rennin) add 5 drops of
gastric juice to 5 mL of milk; coagulation should take place in
20 minutes in the incubator. |
|
leishmanin test, (for
leishmaniasis)leishmanin is injected intradermally; a positive
reaction consists of a palpable nodule developing in 48 to 72
hours and indicates delayed hypersensitivity, but not
necessarily immunity, to Leishmania organisms. The positive
result appears early in some forms of cutaneous and
mucocutaneous leishmaniasis, but only after recovery in the case
of visceral leishmaniasis. Called also Montenegro t. |
|
lepromin test, (for certain types of
leprosy) after intradermal injection of lepromin (q.v.), a
positive reaction consists of either a tuberculin-type reaction
at 48 to 72 hours (Fernandez reaction) or a nodular,
occasionally ulcerated, lesion at 3 to 4 weeks (Mitsuda
reaction). The test is not diagnostic; a large fraction of the
normal population exhibits positive reactivity owing to
sensitivity to cross-reacting antigens. In individuals known to
have leprosy, a positive result on this test is indicative of
tuberculoid or borderline tuberculoid leprosy, and lack of
reactivity is indicative of lepromatous or borderline
lepromatous leprosy. |
|
Lewis and Pickering test, (for peripheral
circulation) vasodilation of a part is produced by warming it
and applying a sphygmomanometer cuff; return of blood to the
part is assessed when the cuff is released. |
|
Lichtheim test, (for aphasia) if a patient
is able to indicate the number of syllables in a word he or she
cannot utter, it indicates that the cortex is less involved than
the association fibers. |
|
Liebermann-Burchard test, (for cholesterol)
dissolve the sample in chloroform and add acetic anhydride plus
concentrated sulfuric acid; cholesterol can be quantitated by
the intensity of the resulting blue-green color. |
|
Liebig test, (for cystine) boil the
suspected substance with a sodium hydroxide solution and a
little lead sulfide; if cystine is present, the lead sulfide
will form a black precipitate. |
|
likelihood ratio test, in statistics, a test
using the ratio of the maximum value of the likelihood function
from one statistical model to that from another model, a smaller
ratio indicating a stronger relationship between the variables. |
|
limulus test, (for gram-negative endotoxin)
an extract of blood cells from the horseshoe crab (Limulus
polyphemus) is exposed to a blood sample from a patient; if the
sample contains gram-negative endotoxin, gelation will occur. |
|
Lindemann test, (for acetoacetic acid in
urine) to about 10 mL of urine add 5 drops of 30 per cent acetic
acid, 5 drops strong iodine solution, and 2 to 3 mL chloroform,
and shake. The chloroform does not change color if diacetic acid
is present, but becomes reddish violet in its absence. Uric acid
also decolorizes iodine, and if much is present, double the
amount of strong iodine solution should be used. |
|
Linder test, see under sign. |
|
lipase test, (for liver function and
pancreatitis)lipase levels in the blood are measured; elevated
levels are seen in impaired liver function and pancreatitis. |
|
liver function test, see specific tests,
such as aminopyrine breath t., fructose tolerance t., galactose
breath t., lipase t. (def. 1), methacetin breath t.,
monoethylglycinexylidide t., Quick t. (def. 1), rose bengal t.,
and sulfobromophthalein excretion t. Increased levels of alanine
aminotransferase, aspartate aminotransferase, alkaline
phosphatase, γ-glutamyl transpeptidase, and 5´-nucleotidase, and
decreased levels of bilirubin, are often seen with impaired
liver function. |
|
log-rank test, a statistical test used to
test the null hypothesis that two groups have the same
distribution of survival by analyzing and comparing the number
of observed and expected deaths for each group each time a death
occurs in either group. |
|
Lombard test, a test for simulated deafness
using a noise maker. |
|
Lücke test, (for hippuric acid) add boiling
hot nitric acid, evaporate, and heat the dry residue; a strong
odor of nitrobenzene proves the presence of hippuric acid. |
|
Lundh test, (for pancreatic function) a
liquid test meal is administered, containing protein, fat, and
sugar; the trypsin concentration in duodenal aspirates is then
measured for several hours. A decrease in trypsin concentration
indicates abnormally low pancreatic secretion. Called also Lundh
test meal. |
|
lupus band test, an immunofluorescence test
to determine the presence and extent of immunoglobulin and
complement deposits at the dermal-epidermal junction of skin
specimens from patients with systemic lupus erythematosus. |
|
lymphocyte proliferation test, a functional
test of the ability of lymphocytes to respond to mitogens,
specific antigens, or allogenic cells. Lymphocytes are cultured
both with and without the stimulant for several days and then
are cultured for several hours with
3H-labeled thymidine. The
ratio of the thymidine uptake in the stimulated and control
cultures is reported as the “stimulation index” (SI) or
“stimulation ratio” (SR). The test with allogenic cells, called
a mixed lymphocyte culture (MLC), is commonly performed for
transplantation tissue typing; all three types of stimulants are
used in investigation of immunodeficiency. Commonly used
mitogens are phytohemagglutinin (PHA), concanavalin A (ConA),
and pokeweed mitogen (PWM); commonly used antigens are PPD
(tuberculin), Candida antigen, and streptokinase-streptodornase.
Called also blastogenesis assay and lymphocyte proliferation
assay. |
|
Machado-Guerreiro test, (for Chagas disease)
a complement fixation test, using as antigen an extract of the
spleen of puppies infected with Trypanosoma cruzi. |
|
McMurray test, (for torn meniscus) the
patient lies supine with knee fully flexed and foot flat on the
table near the buttocks. The examiner stabilizes the flexion
with the thumb and index finger, then holds the heel with the
other hand, rotates the patient's foot fully outward, and slowly
extends the knee to a 900 angle; a palpable or audible “click,”
grinding, pain, or limitation of extension indicates a tear of
the medial meniscus of the knee joint. The lateral meniscus is
tested by repeating the maneuver but rotating the foot inward. |
|
McNemar test, a modified chi-squared test
performed on data with one degree of freedom to compare findings
in a matched analysis or in a before and after study on the same
individual. |
|
MacWilliam test, (for albumin) take 20 mL of
urine and add 2 drops of a saturated solution of sulfosalicylic
acid: if albumin is present, a cloudiness or precipitate will be
seen; if other proteolytic digestion products are present, this
precipitate will disappear on boiling, but appear again on
cooling. |
|
Magpie test, (for salts of mercury) stannous
chloride is added to the suspected solution; a white and gray
precipitate is formed, consisting of metallic mercury and mild
calomel. |
|
maintenance of wakefulness test, measurement
of the length of time for which an individual can remain awake
in a dark, quiet room; used as a measure of physiological
sleepiness. |
|
mallein test, a skin test analogous to the
tuberculin test, using mallein to test for exposure to glanders. |
|
Malot test, a test for the quantitative
determination of phosphoric acid in urine by the reaction with
cochineal and a uranium salt. |
|
Mann-Whitney test, Mann-Whitney U
test, Mann-Whitney-Wilcoxon test, rank sum t. |
|
Mantoux test, a type of intradermal
tuberculin test; 0.1 mL of PPD containing 5 TU is administered,
usually into the forearm; the size of the area of any induration
on the second or third day, combined with risk factors, is used
to determine whether the patient has had exposure to or
infection with Mycobacterium tuberculosis or a related organism. |
|
manual muscle test, (for muscle function)
the therapist manually puts the patient's body part through a
range of motion and records the extent of function and
limitations. |
|
Marlow test, (for heterophoria) one eye is
occluded by a bandage for some time; after the bandage is
removed, measurements for heterophoria are made. |
|
Master “2-step” exercise test, (for coronary
insufficiency) an early exercise test in which a patient stepped
on and off a set of two stairs for a number of trips
standardized for age, weight, and sex, with electrocardiograms
recorded immediately after test cessation. It has been
supplanted by graded exercise tests that can induce higher
levels of stress. |
|
Matas test, (for collateral
circulation) after hyperemia of the limb has been induced with a
tourniquet, the tourniquet is removed and the extent of
collateral circulation is determined by compressing the main
artery. Called also tourniquet t. |
|
maximal exercise test, an exercise test that
continues until the maximal capability of the subject to
exercise has been reached; the endpoint is usually subjective
fatigue, shortness of breath, or chest pain. |
|
Mayer test, (for alkaloids) mercury
bichloride, 13.5 g, and potassium iodide, 50 g, are dissolved in
1000 mL of water; this is used as a test for alkaloid, with
which it gives a white precipitate. |
|
Mayerhofer test, (for tuberculous
meningitis) the reduction of a decinormal solution of potassium
permanganate solution by 1 mL of spinal fluid in an acid medium
is an index of the amount of protein substance present in the
fluid, indicating tuberculous meningitis. |
|
Mazzotti test, (for onchocerciasis) a small
dose of diethylcarbamazine is administered orally; the death of
microfilariae in the skin causes an intensely pruritic rash
within 20 minutes to 24 hours. |
|
MEGX test,
monoethylglycinexylidide t. |
|
Meigs test, (for fat in milk) to 10 mL of
milk in a special apparatus add 20 mL of water, 20 mL of ethyl
ether, and shake. Then add 20 mL of 95 per cent alcohol. Remove
the ethereal layer, evaporate, and weigh. |
|
melanin test, see Thormählen t. |
|
mercury test, see specific tests, including
Magpie t., Reinsch t., and Vogel and Lee t. |
|
methacetin breath test, a breath test of
liver function: the fasting patient is administered a dose of
methacetin labeled with heavy carbon (carbon 13) and breath
levels of carbon dioxide are measured at regular intervals; low
levels of carbon dioxide indicate liver dysfunction such as
cirrhosis. |
|
methyl red test, (for differentiation of
Enterobacteriaceae) the organism is inoculated into a buffered
glucose-peptone broth containing methyl red. In a positive
reaction, the medium remains red after incubation owing to acid
metabolic products. Most Enterobacteriaceae are positive; the
Klebsielleae are negative and Erwinieae are variable. |
|
metyrapone test, (for Cushing syndrome)
plasma 11-deoxycortisol or urinary 17-hydroxycorticosteroids are
measured after the administration of metyrapone; levels are
increased in patients with Cushing disease but not in patients
with ectopic ACTH syndrome. |
|
microprecipitation test, a
precipitin test in which a minute quantity of the serum is
employed. |
|
MIF test, migration inhibitory factor test,
an in vitro test for the production of migration inhibitory
factor (MIF) by lymphocytes in response to specific antigens;
used for evaluation of cell-mediated immunity. MIF production is
absent in certain immunodeficiency disorders, such as DiGeorge
syndrome, Wiskott-Aldrich syndrome, and Hodgkin disease. |
|
milk ring test, abortus Bang ring
t. |
|
40 millimeter test, (for athletic
efficiency) the subject sits with nasal respiration occluded
with a clamp, and by expiring through a mouthpiece, sustains a
column of mercury at the height of 40 mm for as long as
possible. The pulse rate is taken meanwhile, every five seconds.
In a satisfactory test the pulse rate is unaltered for a minute
or more. |
|
Millon test, (for proteins and nitrogenous
compounds) a solution of 10 g of mercury and 20 g of nitric acid
is diluted with water and decanted after standing 24 hours. This
reagent gives a red color with proteins and other substances,
such as tyrosine, phenol, and thymol, which contain the
hydroxyphenyl group. |
|
Mills test, (for tennis elbow) with the
wrist and fingers fully flexed and the forearm pronated,
complete extension of the elbow is painful. |
|
Mitsuda test, lepromin t. |
|
Mittelmeyer test, (for vestibular disorders)
the patient tries to march in place with eyes closed; in
vestibular disorder he or she will turn to the side ipsilateral
to vestibular loss, or contralateral to vestibular excitation. |
|
mixed lymphocyte culture test, see under
culture, and see lymphocyte proliferation t. |
|
mixed triglyceride breath test, a breath
test for pancreatic function; a mixture of synthetic
triglycerides labeled with carbon 13 is administered to the
fasting patient and levels of labeled carbon dioxide in the
breath are subsequently measured at regular time intervals;
excessively low carbon dioxide indicates inadequate pancreatic
lipase in the intestine. |
|
MLB test, monaural loudness
balance t. |
|
Molisch test, (for glucose in urine) add 2
mL of urine, 2 drops of a 15 per cent solution of thymol, and an
equal volume of strong sulfuric acid; a deep red color results.
Called also Molisch reaction.(for glucose in urine) to 1 mL of
urine add 2 or 3 drops of a 5 per cent solution of α-naphthol in
alcohol, then add 2 mL of strong sulfuric acid; a deep violet
color is produced, and a violet precipitate follows if water is
added.(for proteins) the substance is treated with a 15 per cent
alcoholic solution of α-naphthol and then with concentrated
sulfuric acid; a violet color is formed if proteins are present.
Called also Molisch reaction; defs. 2 and 3 called also
alpha-naphthol reaction. |
|
Moloney test, (for delayed
sensitivity to diphtheria toxoid) 0.1 mL of 1:10 dilution of
fluid toxoid is injected intradermally on the flexor surface of
the forearm; the appearance in 12 to 24 hours of an area of
redness with induration of more than 12 mm in diameter is a
positive reaction. |
|
monaural loudness balance test, (for
hearing)MLB test; a test that measures recruitment in bilateral
sensorineural hearing loss; the loudness sensation at impaired
frequencies is compared with that at normal frequencies. |
|
monoethylglycinexylidide test,
(for liver function)MEGX test; the plasma concentration of
monoethylglycinexylidide (MEGX) is measured 15 or 30 minutes
after the intravenous injection of lidocaine; MEGX levels are
reduced in impaired liver function. |
|
mononucleosis spot test, monospot test, a
type of heterophile antibody test for infectious mononucleosis,
a modification of the Paul-Bunnell-Davidsohn test, using horse
erythrocytes instead of sheep erythrocytes; no centrifugation
step is needed and the whole test is performed in minutes. |
|
Montenegro test, leishmanin t. |
|
Morelli test, (to differentiate between an
exudate and a transudate) add a few drops of the suspected fluid
to a saturated solution of mercury bichloride in a test tube; a
flaky precipitate indicates a transudate, a clot indicates an
exudate. |
|
Mörner test, (for tyrosine) to a
small quantity of the crystals in a test tube add a few mL of
Mörner reagent (solution of formaldehyde, 1 mL; distilled water,
45 mL; concentrated sulfuric acid, 55 mL). Heat gently to the
boiling point. A green color shows the presence of tyrosine.see
nitroprusside t. (def. 1). |
|
Morton test, (for metatarsalgia) transverse
pressure is exerted across the heads of the metatarsals; in
metatarsalgia this will cause a sharp pain, especially between
the second and third metatarsals. |
|
Moschcowitz test, (for
arteriosclerosis) the lower limb is rendered bloodless by means
of an Esmarch bandage, which is removed after five minutes; in a
normal limb the color returns in a few seconds, but in an
arteriosclerotic one color returns more slowly. Called also
hyperemia t. |
|
multiple-puncture test, a skin test in which
the material used (e.g., tuberculin) is introduced into the skin
by pressure of several needles or pointed tines or prongs. See
also tine t. and Heaf t. |
|
multiple sleep latency test, measurement of
the speed at which an individual falls asleep when given
multiple opportunities to sleep throughout the day and
instructed not to resist doing so; used as a measure of
physiological sleepiness. |
|
mumps skin test, (for immunity to mumps) an
intradermal test formerly widely used to determine previous
exposure to mumps virus; killed virus (mumps skin test antigen)
is injected intradermally; a positive response is development of
tuberculin-type delayed hypersensitivity. |
|
murexide test, Weidel t. (def.
1). |
|
Murphy test, (for location of
deep-seated muscular pain) the patient sits with arms folded in
front; the examiner's thumb is placed under the twelfth rib and
short jabbing movements are made to determine the origin of
deep-seated tenderness and muscular rigidity. Called also Murphy
kidney punch. |
|
Naffziger test, (for nerve root compression)
increase or aggravation of pain or sensory disturbance over the
distribution of the involved nerve root upon manual compression
of the jugular veins bilaterally confirms the presence of an
extruded intervertebral disk or other mass. |
|
Nagel test, (for color vision) one half of
the field of an anomaloscope is illuminated with standard yellow
and the subject must mix red and green until the second half
matches the first. |
|
Nagler test, see under reaction. |
|
NBT test, nitroblue tetrazolium
t. |
|
Nencki test, (for indole) treat the
suspected material with nitric acid and a little nitrous acid; a
red color follows, and in concentrated solution a red
precipitate may appear. |
|
neostigmine test, (for myasthenia
gravis) used in children, and in adults suspected of having
myasthenia gravis but with a negative Tensilon test; neostigmine
methylsulfate mixed with atropine sulfate is injected
intramuscularly; lessening of myasthenic symptoms is indicative
of the disease. Called also Prostigmine t. |
|
Neufeld test, see under reaction. |
|
neutralization test, a test for the power of
an antiserum, antibiotic, antitoxin, antiviral, or other
substance to antagonize the pathogenic properties of a
microorganism, virus, bacteriophage, or toxic substance. Called
also protection t. and serum neutralization t. |
|
niacin test, (for Mycobacterium
tuberculosis) either of two tests to distinguish strains of M.
tuberculosis by adding aniline, ethanol, and cyanogen bromide to
a culture; this will turn human M. tuberculosis yellow because
of its niacin content. |
|
Nickerson-Kveim test, Kveim t. |
|
Ninhydrin test, triketohydrindene
hydrate test. |
|
nitrate reduction test, (for bacteriuria or
presence of bacteria in other fluids) a type of nitrite test
that identifies the reduction of nitrate to nitrite by a
bacterial culture. The fluid under investigation is cultured in
a broth containing nitrate and the medium is tested for nitrite
by mixing with solutions containing sulfanilic acid and
alpha-naphthylamine in 5 N acetic acid; a red color indicates
the presence of nitrite. The test is useful in identifying
doubtful strains of Enterobacteriaceae, mycobacteria, and
certain aerobic bacteria. |
|
nitrite test, (for nitrites in saliva) to
the saliva add 1 or 2 drops of sulfuric acid, a few drops of
potassium iodide solution, and some starch paste; a blue color
indicates nitrites.a test for nitrites in any fluid; see
specific tests, including Griess t., nitrate reduction t., and
Schaffer t. |
|
nitroblue tetrazolium test, (for neutrophil
microbicidal function) neutrophils are incubated with latex
particles and nitroblue tetrazolium (NBT). Normally phagocytosis
of the particles is accompanied by reduction of NBT to a blue
formazan pigment; absence of NBT reduction indicates a defect in
some of the metabolic pathways involved in intracellular
microbial killing, as seen in chronic granulomatous disease.
Called also NBT t. |
|
nitrogen washout test, (for
functional residual capacity of lungs) with the patient inhaling
pure oxygen, the concentration of exhaled nitrogen is obtained
for each breath until it falls below 1 per cent of the gas being
exhaled (usually about seven minutes' time); the total volume of
nitrogen that has been exhaled at this point is assumed to be
0.8 of the functional residual capacity. |
|
nitrogen washout test, single breath, the
patient inhales a vital capacity's volume of pure oxygen and
then slowly exhales. The nitrogen concentration of the exhaled
gas is measured over the entire breath and a curve is generated;
different parts of the curve represent nitrogen concentrations
of gas in different components of the vital capacity, and can be
analyzed for uniformity of ventilation and determination of
anatomic dead space and closing volume. Called also single
breath t. and single breath oxygen t. |
|
nitroprusside test, (for cysteine) if a
protein containing cysteine is dissolved in water and 2 to 4
drops of a 4 or 5 per cent solution of sodium nitroprusside and
then a few drops of ammonia are added, a deep purple-red color
appears; called also Mörner t.(for creatinine) see Weyl t. (def.
1). |
|
nitroso-indole-nitrate test, (for indole and
skatole) acidify the unknown with nitric acid and add a few
drops of potassium nitrite; a red color or a red precipitate
indicates indole, a white turbidity indicates skatole. |
|
nocturnal penile tumescence test,
monitoring of erections occurring during sleep; in the
differential diagnosis of psychogenic and organic impotence, the
former is generally associated with the presence of normal
patterns of nocturnal erection while the latter is not. Called
also NPT t.. |
|
nonparametric test, one using nonparametric
statistics, such as the rank sum test or signed rank test;
nonparametric tests are often less powerful than parametric
tests but are valid in cases where parametric tests are not. |
|
nonstress test, the monitoring of the
response of the fetal heart rate to fetal movements by
cardiotocography; a reactive (normal) test consists of two or
more fetal movements occurring within 20 minutes accompanied by
acceleration of the fetal heart rate by at least 15 beats per
minute for at least 15 seconds with a long-term variability of
at least 10 beats per minute. |
|
nontreponemal antigen test, see
serologic t. for syphilis. |
|
NPT test, nocturnal penile
tumescence t. |
|
nucleic acid test, any of various
tests that use molecular biology techniques to detect and
identify microorganisms, including viruses, on the basis of
their nucleic acids. It includes culture confirmation tests,
which identify organisms grown in culture, and direct tests,
which can identify the organisms directly in a specimen. Direct
tests can be further subdivided on the basis of whether their
target nucleic acids are nonamplified or amplified for the test;
the former are based on identification of a unique target
sequence using a labeled probe; the latter are classified as
nucleic acid amplification tests (q.v.). |
|
nucleic acid amplification test, any nucleic
acid test (q.v.) that uses nucleic acid amplification techniques
in a direct test for the presence of a specific pathogen in a
sample; such tests do not depend on the production of antibody
by the pathogen, and can be rapid, highly sensitive, and very
specific. |
|
nystagmus test, caloric t. |
|
Oakley-Fulthorpe test, see under
technique. |
|
Ober test, (for hip contracture) the patient
lies on the side opposite that to be tested, with the underneath
hip and knee flexed; with the upper knee flexed to a right
angle, the upper hip is flexed to 90 degrees, fully abducted,
brought into full hyperextension, and allowed to adduct; the
angle that the thigh makes above the horizontal is the degree of
abduction contracture. |
|
occult blood test, see specific tests,
including guaiac t., and Hemoccult. |
|
octanoic acid breath test, a breath test for
gastric emptying: the patient is administered a test meal
containing octanoic acid labeled with carbon 13, and the breath
is assessed at intervals for levels of labeled carbon dioxide;
excessive carbon dioxide is seen when gastric emptying is
inadequate. |
|
one-stage prothrombin test,
one-stage prothrombin time test, prothrombin time. |
|
one-tailed test, a hypothesis
test (q.v.) in which the critical region is one tail of the
distribution of the test statistic and the null hypothesis is
tested against a one-sided alternative that includes deviations
from the null hypothesis only in one direction, deviations in
the other direction being of no consequence. |
|
ONPG test, (for β-galactosidase in bacteria)
the organism is grown in a buffered peptone medium containing
d-nitrophenyl-β-d-galactopyranoside (ONPG): production of
β-galactosidase is indicated by the appearance of a yellow
color. Used to differentiate Salmonella (positive) from Arizona
(negative), and Neisseria lactamicus (positive) from N.
meningitidis (negative). |
|
opticokinetic drum test,
optokinetic test, optokinetic drum test, (for vision) a rotating
drum or other figure is used, painted with vertical black and
white stripes; because the eye involuntarily follows such a
figure, this can be used in the differential diagnosis of
psychogenic blindness, to detect the presence of vision in
infants, and to check for normality of opticokinetic nystagmus. |
|
orcinol test, Bial t. |
|
orientation test, testing whether the
patient can correctly give the time of day, the day of the week,
month, and year, and the place. |
|
osmotic fragility test, (for spherocytosis)
heparinized or defibrinated blood is placed in tubes of sodium
chloride solution (pH 7.4) varying in concentration from 0.85 to
0.00 per cent (w/v); the amount of hemolysis in each tube is
determined colorimetrically. Increased fragility indicates
spherocytosis. |
|
Osterberg test, (for β-hydroxybutyric acid)
to 800 mg of ammonium sulfate add 0.15 mL of concentrated
ammonium hydroxide solution, 2 drops of a 5 per cent solution of
nitroprusside, and 1 mL of the urine. Dilute to 50 mL and
compare with a standard. |
|
Ouchterlony test, double
diffusion in two dimensions; see under diffusion. |
|
Oudin test, see under technique. |
|
oxytocin challenge test, a contraction
stress test in which uterine contractions are stimulated by
intravenous infusion of oxytocin. |
|
Pachon test, (for collateral circulation)
measuring of the blood pressure in cases of aneurysm to
determine the state of the collateral circulation. |
|
Paget test, a solid tumor is most hard in
its center, whereas a cyst is least hard in its center. |
|
pancreatic function test, see specific
tests, such as bentiromide t., cholecystokinin t., Lundh t.,
mixed triglyceride breath t., pancreolauryl t., secretin t., and
triolein breath t. |
|
pancreolauryl test, (for pancreatic
function)fluorescein dilaurate is administered orally and its
cleavage to yield lauric acid is monitored as a measure of
pancreatic esterase activity. |
|
Pap test, Papanicolaou test, an exfoliative
cytological staining procedure for detection and diagnosis of
various conditions, particularly malignant and premalignant
conditions of the female genital tract (cancer of the vagina,
cervix, or endometrium). Cells that have been desquamated from
the genital epithelium are obtained by smears, fixed and
stained, and examined under the microscope for evidence of
pathologic changes. The test is also used in detection of human
papillomavirus infection, evaluation of endocrine function, and
diagnosis of malignancies of other organs, such as the breast or
organs of the respiratory tract and lungs, gastrointestinal
tract, or urinary tract. Called also Pap or Papanicolaou smear.
See also Papanicolaou stain, at Stains and Staining Methods
under stain. |
|
parametric test, one using parametric
statistics, i.e., one that depends upon assumptions about the
distribution of the data. |
|
partial thromboplastin time test,
see under time. |
|
passive cutaneous anaphylaxis
test, see passive cutaneous anaphylaxis, under anaphylaxis. |
|
passive protection test, a test in which
antiserum is tested for protective antibody by parenteral
inoculation of groups of animals with graded doses in constant
volume. |
|
passive transfer test, see
Prausnitz-Küstner reaction, under reaction. |
|
patch tests, skin tests, used primarily in
the diagnosis of allergies, in which small pieces of gauze or
filter paper impregnated with suspected allergens are applied to
the skin for fixed time periods; swelling or redness constitutes
a positive reaction. |
|
Patrick test, (for arthritis of
the hip) with the patient supine, the thigh and knee are flexed
and the external malleolus is placed over the patella of the
opposite leg; the knee is depressed, and if pain is produced,
arthritis of the hip is indicated. Patrick called this test
fabere sign, from the initial letters of movements that are
necessary to elicit it, namely, flexion, abduction, external
rotation, extension. |
|
Paul-Bunnell test, the original
heterophile antibody test, which determined the highest dilution
of the patient's serum that was capable of agglutinating sheep
red blood cells. |
|
Paul-Bunnell-Davidsohn test, a type of
heterophile antibody test for infectious mononucleosis, a
modification of the Paul-Bunnell test that differentiates among
three types of heterophile sheep erythrocyte agglutinins: those
associated with infectious mononucleosis, those associated with
serum sickness, and natural antibodies against Forssman antigen.
The patient's serum is absorbed with guinea pig kidney cells or
with beef erythrocytes and centrifuged. Unabsorbed serum has an
abnormally high heterophile antibody titer in infectious
mononucleosis and serum sickness. Absorption with guinea pig
kidney removes Forssman antibodies and serum sickness
heterophile antibodies. Absorption with beef erythrocytes
removes heterophile antibodies associated with infectious
mononucleosis and serum sickness. Called also Davidsohn
differential absorption t. |
|
PCA test, see passive cutaneous
anaphylaxis. |
|
pentagastrin test, pentagastrin stimulation test,
(for gastric function) after the patient
fasts overnight, a basal acid output and its pH are obtained for
secretion of stomach acid. Then pentagastrin is administered
into the stomach through a nasogastric tube and maximal acid
output and peak acid output values are obtained. See basal,
maximal, and peak acid outputs, under output. |
|
peptide test, see
triketohydrindene hydrate t. |
|
peptone test, see specific tests, including
Hofmeister t. (def. 2) and triketohydrindene hydrate t. |
|
perchlorate discharge test, a thyroid
function test; one to two hours after administration of
radioiodine, perchlorate is administered to block further iodine
uptake and flush from the thyroid gland any that has not bound
to thyroid proteins. In euthyroid patients only trace amounts
will be flushed out; the discharge of significant amounts
indicates a defect in thyroid iodine binding. |
|
performance test, an intelligence test in
which the subject is required to carry out certain actions
rather than to answer questions. |
|
Peria test, Piria t. |
|
peritoneal equilibration test, (for adequacy
of peritoneal dialysis) after a certain specific dwell time of
the dialysis solution, ratios are calculated of the difference
in plasma and dialysis solution concentrations of solutes such
as creatinine, glucose, other small solutes, and proteins at
different times during the remainder of the procedure. |
|
Perls test, (for hemosiderin) the substance
being examined is treated with hydrochloric acid and potassium
ferrocyanide; the Prussian blue reaction is produced if
hemosiderin is present. |
|
permanganate test, see Weisz t. |
|
Perthes test, (for collateral
circulation in patients with varicose veins) a bandage is
applied just below the knee and the patient walks around with it
on; varicose veins of the leg will become evacuated from
continuous compression if there is sufficient collateral
circulation in the deep veins. Called also tourniquet t. |
|
phenacetin test, (for phenacetin in urine)
to the urine add a little concentrated hydrochloric acid, a
small amount of 1 per cent solution of sodium nitrate, and a
small amount of alkaline α-naphthol solution; make alkaline and
a red color indicates phenacetin. |
|
phenol test, see specific tests,
including Jacquemin t. |
|
phenolphthalein test, (for blood) boil a
thin fecal suspension, cool, and add it to half as much reagent
(made by dissolving 1 to 2 g of phenolphthalein and 25 g of
potassium hydroxide in water). Add 10 g of metallic zinc and
heat until decolorized. A pink color indicates the presence of
blood.(in urine) make the urine alkaline; a red color indicates
phenolphthalein. |
|
photopatch test, a type of patch test for
assessing the photosensitization potential of medications and
other chemicals. On the patient's back, each substance is
applied in two different locations; then one spot of each
substance is irradiated. A positive reaction at only the
irradiated site of a substance indicates photoallergy; reaction
at both the irradiated and the nonirradiated sites indicates a
different type of allergic reaction. |
|
pinch test, (for hand dexterity) a test
measuring any of the various pinches of the hand. |
|
pine wood test, (for indole) a pine splinter
moistened with concentrated hydrochloric acid is turned cherry
red by a solution of indole. |
|
Piria test, (for tyrosine)
moisten the suspected material with strong sulfuric acid and
warm it; then dilute and warm it again; neutralize it with
barium carbonate, filter, and add ferric chloride in dilute
solution: if tyrosine is present, a violet color is seen, which
is destroyed by an excess of ferric chloride. Also spelled Peria
t. |
|
Pirquet test, a formerly much used
tuberculin test in which the tuberculin is applied by
scarification; called also Pirquet reaction. |
|
pivot shift test, see under
phenomenon. |
|
P-K test, see Prausnitz-Küstner
reaction, under reaction. |
|
plantar ischemia test, (for circulatory
disturbances in legs and feet) the elevated leg is alternately
flexed and extended and the plantar surface of the patient's
foot is checked for blanching. |
|
pointing test, Bárány pointing t. |
|
Politzer test, see under method. |
|
porphobilinogen test, a test for the
presence of porphobilinogen; see Watson-Schwartz t. |
|
Porteus maze test, a performance test in
which the subject is required to trace with a pencil through
printed mazes of increasing difficulty. |
|
postcoital test, (for infertility)
examination of secretions aspirated from the vaginal fornix and
endocervical canal after coitus, to determine the number and
condition of spermatozoa present and the extent to which they
have penetrated the cervical mucus. Called also Huhner t. and
Sims t. |
|
posterior drawer test, see drawer
t's. |
|
Prausnitz-Küstner test, see under
reaction. |
|
precipitin test, any serologic test based on
a precipitin reaction (q.v.). |
|
pregnancy test, a test for
detection or confirmation of pregnancy; currently it is usually
an immunologic test measuring the level of human chorionic
gonadotropin in the urine, which rises to detectable levels soon
after fertilization; see also early pregnancy t. |
|
Preyer test, a spectroscopic test for carbon
monoxide in the blood. |
|
Proetz test, (for acuity of sense of smell)
use of a series of substances each in 10 different
concentrations in a liter of petroleum of specific gravity
0.880, to determine the least concentration at which the
substance can be recognized, termed olfactory coefficient or
minimal identifiable odor. |
|
projective test, any of various tests in
which an individual interprets ambiguous stimulus situations,
e.g., a series of inkblots (Rorschach t.), according to their
own unconscious dispositions, thus yielding information about
their personality structure, its underlying dynamics, and
possible psychopathology. |
|
Prostigmine test, neostigmine t. |
|
protection test, neutralization
t. |
|
protein test, see specific tests, including
biuret reaction, Gies biuret t., Grigg t., Reichl t., Schulte
t., sulfur t., and triketohydrindene hydrate t. |
|
protein-bound iodine test, a formerly common
thyroid function test in which the amount of iodine firmly bound
to protein in the serum was determined by precipitating the
proteins, yielding an estimate of serum thyroid hormone
concentration. Errors were introduced if iodine compounds from
nonthyroid sources were present. |
|
protein truncation test, a method for
detection of one or more translation termination mutations in a
gene that cause a truncated, usually inactive, protein to be
synthesized; the appropriate genomic DNA or mRNA is isolated,
amplified by polymerase chain reaction, and used as a template
for in vitro transcription and translation. The size of the
resulting protein is compared to that of a wild type protein by
means of SDS–polyacrylamide gel electrophoresis. |
|
prothrombin test, prothrombin time.two-stage
prothrombin time t. |
|
prothrombin consumption test, a test
formerly much used to measure the formation of intrinsic
thromboplastin by determining the residual serum prothrombin
after the completion of blood coagulation. |
|
prothrombin-proconvertin test, a test
formerly used in the control of coumarin-type anticoagulants,
employing a saline extract of brain as a thromboplastin and
requiring presence of excess blood coagulation factor V. |
|
provocative test, challenge (def.
3). |
|
psychological test, any test to measure a
subject's development, achievement, personality, intelligence,
thought processes, etc. |
|
psychomotor test, a test that assesses the
subject's ability to perceive instructions and perform motor
responses, often including measurement of the speed of the
reaction. |
|
pulmonary function test, any of numerous
tests that measure aspects of the respiratory system in order to
assess functional state and presence or nature of any disease
process. Factors evaluated include lung mechanics (capacities,
flow rates, and volumes), gas exchange, pulmonary blood flow,
blood gases, and pH of blood. |
|
pulp test, a diagnostic test to determine
tooth pulp vitality or abnormality, usually by means of electric
pulp testers or by application of a hot or cold stimulus. |
|
Queckenstedt test, see under
sign. |
|
quellung test, Neufeld reaction;
see under reaction. |
|
Quick test, (for liver function) a test
based on excretion of hippuric acid following administration of
sodium benzoate.prothrombin time. |
|
radioactive iodine uptake test, one of the
most common thyroid function tests; a known quantity of
radioiodine is administered and 24 hours later the per cent is
calculated that has been absorbed by the thyroid gland. Patients
who have recently been exposed to iodine compounds, such as in
dietary supplements, contrast media, medications, or
antiseptics, may not be good candidates for this test. |
|
radioallergosorbent test, a test used to
measure specific IgE antibodies in serum. Allergen extract is
coupled to a solid matrix (paper, cellulose particles); this
immunosorbent is reacted with serum and washed and then reacted
with radiolabeled anti–human IgE antibody and washed. Uptake of
the labeled antibody is proportional to the level of specific
serum IgE antibodies to the allergen. RAST is used as an
alternative to skin tests to determine sensitivity to suspected
allergens. |
|
radioiodine uptake test,
radioactive iodine uptake t. |
|
radioimmunosorbent test, a highly
sensitive radioimmunoassay for measuring the total IgE antibody
concentration in serum; the serum sample is reacted with
radiolabeled IgE and anti–human IgE antibody coupled to an
insoluble support. The amount of labeled IgE remaining bound to
the immunosorbent varies inversely with the amount of
(unlabeled) IgE present in the sample. |
|
radioisotope renal excretion test, (for
kidney function) radioisotopic material diluted with saline is
rapidly injected into a well-hydrated patient; urine collected
through a catheter is examined at known intervals and the
radioactivity of each specimen is determined and recorded. |
|
Ramon flocculation test, a test formerly
widely used to assess the quality of toxoid-based vaccines; to a
series of tubes containing a constant amount of toxin, such as
diphtheria toxin, antitoxin is added in increasing amounts; when
flocculation occurs, it indicates a neutralized mixture of toxin
and antitoxin. |
|
rank sum test, a nonparametric statistical
test for ordinal data, testing the null hypothesis that two
samples are drawn from the same population versus the
alternative hypothesis that the two samples are drawn from two
populations having probability distributions of the same shape
but different locations. It is based on the value of the rank
sum statistic, which is calculated as the sum of the ranks of
each sample after the observations in both samples are jointly
ranked in ascending order; if and only if the null hypothesis is
true, the average ranks of the two samples will be similar.
Called also Mann-Whitney U t., Mann-Whitney-Wilcoxon t., and
Wilcoxon rank sum t. |
|
rapid plasma reagin test, RPR test; a type
of card test that is a flocculation test widely used in
screening for syphilis. Unheated serum and a modified VDRL
antigen containing choline chloride and charcoal particles are
placed on a plastic-coated white card, followed by macroscopic
identification of the flocculation. |
|
Raygat test, hydrostatic t. |
|
Rebuck test, Rebuck skin window
technique. |
|
red-glass test, (for ocular deviation) a red
glass is placed over the right eye while the patient looks at a
light; the position at which the patient sees the red image
reveals any affected muscle. |
|
Rees test, (for albumin) small amounts of
albumin are precipitated from solution by tannic acid in
alcoholic solution. |
|
Rehberg test, a formerly used
test of creatinine clearance. |
|
Reichl test, (for proteins) add 2 or 3 drops
of an alcoholic solution of benzaldehyde and a quantity of
sulfuric acid previously diluted to twice its volume with water;
then add a few drops of ferric sulfate solution. The mixture
will take on a deep-blue color if proteins are present. |
|
Reinsch test, (for heavy metals, including
arsenic, mercury, bismuth, antimony, and large amounts of
selenium, tellurium, and sulfide) insert a strip of clean copper
into the suspected acidified liquid or finely ground tissue, and
boil; if one or more heavy metals are present, a coating will
form on the copper strip. |
|
renal function test, kidney
function t. |
|
resorcinol–hydrochloric acid
test, Selivanoff t. |
|
Reuss test, (for atropine) the substance
examined is treated with sulfuric acid and oxidizing agents; if
atropine is present, an odor of roses and orange-flowers is
given off. |
|
rheumatoid arthritis test, see specific
tests, such as the latex agglutination t., Rose-Waaler t., and
sheep cell agglutination t. |
|
Rideal-Walker test, see under
method. |
|
RIF test, Rubin t. (def. 2). |
|
ring test, (for antibiotic activity) the
solution is placed in a ring resting on the surface of seeded
agar and the size of the surrounding clear area of inhibition
indicates the activity. |
|
Rinne test, (for hearing) with the opposite
ear masked, vibrating tuning forks of 256, 512, and 1024 Hz
alternately have their stems placed on the mastoid process and
just outside the external auditory meatus until nothing is heard
at one of these positions. When air conduction is greater than
bone conduction(positive Rinne test), it indicates normal
hearing or sensorineural hearing loss. When bone conduction is
greater than air conduction(negative Rinne test), it indicates
conductive hearing loss. |
|
Rivalta test, see under reaction. |
|
rollover test, (for risk of preeclampsia in
pregnant women) a comparison of blood pressure is made with the
woman lying on her left side and on her back; an excessive
increase in blood pressure when she rolls to the supine position
indicates increased risk of preeclampsia. |
|
Romberg test, (for
differentiating between peripheral and cerebellar ataxia) an
increase in clumsiness in all movements and in the width and
uncertainty of the gait when the patient's eyes are closed
indicates peripheral ataxia; no change indicates the cerebellar
type. See also Romberg sign, under sign. |
|
Ronchese test, (for ammonia in urine) one
based on the action of formaldehyde on ammonia salts. A 10 per
cent solution of sodium carbonate is slowly added to urine until
the reaction becomes neutral. A 40 per cent solution of
formaldehyde is neutralized with a one-fourth normal sodium
solution against phenolphthalein until it becomes slightly pink.
Then 25 mL of the neutral urine and 10 mL of the neutral
solution of formaldehyde are mixed and titrated against
decinormal sodium carbonate solution until a deep pink develops.
Each mL of the decinormal sodium carbonate solution per 100 mL
of urine corresponds to 0.017 g ammonia in 1000 mL of urine. |
|
Rorschach test, a projective test in which
the subject is asked to relate his associations to a series of
inkblot designs. |
|
Rose-Waaler test, an agglutination test for
rheumatoid factor (RF) using tanned sheep red blood cells (SRBC)
coated with subagglutinating amounts of rabbit anti-SRBC IgG
antibody. These cells agglutinate when exposed to RF (anti-IgG
autoantibodies) owing to cross-reaction between human and rabbit
IgG. |
|
rose bengal test, (for liver
function) a solution of radiolabeled rose bengal sodium I 131 is
injected into the bloodstream. It should disappear from the
blood rapidly; delayed clearance time points to diminished
activity of the liver. |
|
Rosenbach-Gmelin test, (for bile pigment)
filter the urine through a very small filter, and put a drop of
nitric acid with a trace of nitrous acid on the inside of the
filter; a pale yellow spot will appear, surrounded with
yellowish red, violet, blue, and green rings. |
|
Rosenthal test, (for blood in urine) add
potassium hydroxide solution to the urine, remove the
precipitate, and dry it; place a small amount on a slide with a
crystal of sodium chloride; apply a coverglass and cause a few
drops of glacial acetic acid to flow under it; warm the plate.
When it is cool, hemin crystals will appear if blood is present. |
|
Rothera test, (for acetone) to 5 mL of urine
add a little solid ammonium sulfate and add 2 to 3 drops of a
fresh 5 per cent solution of sodium nitroprusside and 1 to 2 mL
of ammonium hydroxide; a purple color forms if acetone is
present. |
|
Rous test, (for hemosiderin in urine) the
urine sample is centrifuged; to the sediment add 5 mL of a 2 per
cent solution of potassium ferrocyanide and 5 mL of a 1 per cent
solution of hydrochloric acid. Hemosiderin granules stain blue. |
|
RPR test, rapid plasma reagin t. |
|
Rubin test, (for patency of uterine tubes)
transuterine insufflation is done with carbon dioxide. If the
tubes are patent the gas enters the peritoneal cavity and may be
demonstrated by the fluoroscope or radiograph. This subphrenic
pneumoperitoneum may cause pain in one or both shoulders of the
patient. If the manometer registers not over 100 mm Hg the tubes
are patent; if between 120 and 130, there may be stenosis or
stricture, but not complete occlusion; if it rises to 200, the
tubes are completely occluded.(for avian leukosis viruses in
egg-culture vaccines) if the viruses are present, they induce a
cellular resistance to Rous sarcoma viruses subsequently
inoculated (resistance-inducing factor). Called also RIF t. |
|
Rubner test, (for carbon monoxide in blood)
shake the blood with 4 or 5 volumes of lead acetate in solution:
if the blood contains CO, it will retain its bright color; if
not, it becomes a chocolate brown.(for lactose, glucose,
maltose, or fructose in urine) add lead acetate to the urine,
boil, and then add an excess of ammonium hydroxide: lactose
gives a brick-red color, glucose a coffee-brown color, maltose a
light-yellow color, and fructose no color at all. |
|
ruler test, Hamilton t. |
|
Rumpel-Leede test, see under
phenomenon. |
|
Russell viper venom test, Stypven
time t. |
|
Ruttan and Hardisty test, (for blood) blood
in the presence of a 4 per cent glacial acetic acid solution of
orthotoluidine and hydrogen peroxide gives a bluish color. |
|
Sabin-Feldman dye test, (for toxoplasmosis)
a serologic test based on the failure of living toxoplasmas, in
the presence of specific antibody and accessory factor, to take
up methylene blue dye. |
|
saccharimeter test, glucose in solution
rotates the plane of polarized light to the right, while
fructose turns it to the left. |
|
saccharin test, (for mucociliary
clearance) the upper respiratory tract is cleaned and small
crystals of saccharin are placed on the inferior nasal mucosa.
The time is measured until the patient has a sweet taste in the
mouth. With normal ciliary transport the time should be 30
minutes or less; a time of more than 1 hour indicates pathology. |
|
Sakaguchi test, (for arginine) a reddish or
wine color is produced in the presence of arginine when a tissue
section is treated with an alkaline mixture of α-naphthol and
sodium hypochlorite. |
|
Salkowski test, (for carbon
monoxide in the blood) add to the blood 20 volumes of water and
sodium hydroxide in solution; if CO is present, it becomes
cloudy and then red, and eventually flakes of red float on the
surface.(for cholesterol) dissolve the sample in chloroform and
add an equal volume of strong sulfuric acid; if cholesterol is
present, the solution becomes bluish red and slowly changes to a
violet red, and the sulfuric acid becomes red, with a green
fluorescence.(for indole) to the solution to be tested add a
little nitric acid, and drop in slowly a solution of potassium
nitrite (2 per cent): a red color shows that indole is present,
and a red precipitate is afterward formed.(for creatinine) to
the yellow solution obtained in the Weyl test, add an excess of
acetic acid and heat; a green color results, which turns to
blue. |
|
Sandrock test, (for thrombosis) vigorous
friction is applied to the part; the degree of hyperemia which
follows is an indication of the condition of the circulation. |
|
scarification test, a skin test in which the
antigen is introduced by scarification. |
|
Schaffer test, (for nitrites in urine)
decolorize 4 mL of urine with animal charcoal and add to it 4 mL
of 10 per cent acetic acid and 3 drops of 5 per cent solution of
potassium ferrocyanide; an intense yellow color indicates
nitrites. |
|
Schick test, (for reactivity or immunity to
diphtheria toxin) an intradermal test in which diphtheria toxin
equal to one-fiftieth of the minimum lethal dose for a guinea
pig is injected into one of the subject's arms (the test site)
and an equal quantity of heat-inactivated diphtheria toxin is
injected into the other arm (the control site). A positive
reaction consists of redness at the test site only, appearing in
24 to 36 hours and persisting for 4 to 5 days, leaving a brown
spot on the skin; this indicates lack of immunity to diphtheria.
Immunity is indicated by either a pseudoreaction (redness at
both sites, usually disappearing in 48 hours without residual
pigmentation) or a negative reaction. |
|
Schiller test, (for cancer of cervix) a test
for early squamous cell cancer by treating the tissue with a
solution of 1 g of iodine and 2 g of potassium iodide in 300 mL
of water: if the cervix is healthy, the surface turns brown; if
there is cancer, the treated area turns white or yellow, because
cancer cells do not contain glycogen and therefore do not stain
with iodine. |
|
Schilling test, (for gastrointestinal
absorption of vitamin B12)
a measured amount of radioactively labeled cyanocobalamin is
given orally, followed by a parenteral flushing dose of the
nonradioactive vitamin, and the percentage of radioactivity is
determined in the urine excreted over a 24-hour period. The test
is usually done three times: first with added intrinsic factor,
then without it, and then after antibiotic therapy. The results
are used in the diagnosis of pernicious anemia and other
disorders of vitamin B12
metabolism. |
|
Schirmer test, (for
keratoconjunctivitis sicca) a test of tear production in which a
piece of filter paper is inserted over the conjunctival sac of
the lower lid, with the end of the paper hanging down on the
outside. The range of normal wetting, determined by measuring
the area of moisture on the projecting paper, depends on age,
sex, and disease processes. |
|
Schlichter test, serum
bactericidal activity t. |
|
Schober test, (for range of motion of lumbar
spine) with the patient standing erect, marks are drawn 5 cm
above and 10 cm below the posterior superior iliac spine; when
the patient bends at the waist to the most flexion possible, the
distance between the two marks should increase to at least 20
cm; if the distance is less, there is decreased range of motion,
such as with ankylosing spondylitis. |
|
Schönbein test, (for blood) blue coloration
obtained by adding solution of hydrogen peroxide to tincture of
guaiac mixed with suspected blood.(for copper) a solution
containing a copper salt becomes blue if potassium cyanide and
tincture of guaiac are added. |
|
Schroeder test, (for urea) add a crystal of
the substance to a solution of bromine in chloroform; the urea
will decompose and gas will be formed. |
|
Schulte test, (for proteins) remove all
coagulable protein, precipitate with six volumes of absolute
alcohol, dissolve the precipitate in water, and apply the biuret
test. |
|
Schultze test, (for cellulose) iodine is
dissolved to saturation in a zinc chloride solution, and 6 parts
of potassium iodide are added: this reagent colors cellulose
blue.(for cholesterol) evaporate with nitric acid, using a
porcelain dish and water bath; if cholesterol is present, a
yellow deposit is formed, which changes to yellowish red when
ammonia is added. |
|
Schumm test, benzidine t.(for
heme in plasma) a given volume of plasma is covered with a layer
of ether; one-tenth the volume of concentrated ammonium sulfide
(analar) is then run in with a pipette and subsequently mixed by
shaking. A positive reaction is indicated by the appearance of a
hemochromogen with a sharply defined α band at 558 nm in a depth
up to 4 cm of plasma. |
|
Schwabach test, (for hearing) with the
patient's opposite ear masked, vibrating tuning forks of 256,
512, 1024, and 2048 Hz have their stems placed first on the
patient's mastoid process and then on that of the examiner
(whose hearing should be normal), until sound is no longer heard
by one of them. The result is expressed as “Schwabach prolonged”
if heard longer by the patient (indicative of conductive hearing
loss), as “Schwabach shortened or diminished” if heard longer by
the examiner (indicative of sensorineural hearing loss), and as
“Schwabach normal” if heard for the same time by both. |
|
SCMC test, (for cervical factor infertility)
fresh sperm is put both on a slide with cervical mucus and on a
slide without mucus, and motility of the two sperm samples is
assessed over time. If the sperm shows irregularities of
motility through the mucus, there is cervical factor
infertility. Called also Kremer t.. |
|
scratch test, a skin test in
which the antigen is applied on a superficial scratch. |
|
screen test, alternate cover t.cover-uncover
t. |
|
screening test, any test used to eliminate
those who are definitely not affected by the disease in
question, the remainder (those with positive reactions) being
subjected to more refined diagnostic tests. |
|
secretin test, (for pancreatic function)
after intravenous injection of secretin, pancreatic secretions
are measured by collection through a tube in the duodenum.(for
hypergastrinemia) basal values of gastrin are obtained and
secretin is administered intravenously; levels of gastrin are
then measured at short intervals to assess whether its secretion
is normal or abnormal. Defs. 1 and 2 called also intravenous
secretin t. and secretin injection or secretin stimulation t. |
|
secretin-cholecystokinin test, (for
pancreatic function) a combination of the secretin test and the
cholecystokinin test, measuring pancreatic secretion volume and
secretion of bicarbonate, amylase, lipase, and trypsin. Called
also secretin-pancreozymin t. |
|
secretin injection test, secretin
t. |
|
secretin-pancreozymin test,
secretin-cholecystokinin t. |
|
secretin stimulation test,
secretin t. |
|
SeHCAT test, (for absorption of bile salts)
the bile acid analogue SeHCAT (75 selenium homocholic acid,
labeled with radioactive selenium-75) is administered; seven
days later, the amount left in the body is measured. |
|
Selivanoff (Seliwanow) test, (for fructose
in urine) to the urine is added an equal volume of hydrochloric
acid containing resorcinol; formation of a dark red color after
boiling for 10 seconds indicates fructose. Called also
resorcinol–hydrochloric acid t. and Selivanoff reaction. |
|
sentence completion test, a projective test
for assessing personality and possible psychopathology, in which
the individual is asked to provide endings for unfinished
sentences. |
|
Sereny test, (for invasiveness of bacteria)
the organism is inoculated into the eye of a guinea pig;
invasiveness is determined by the organism's ability to produce
conjunctivitis. The test is used particularly for determining
the invasiveness of strains of Escherichia coli and Listeria
monocytogenes. |
|
serologic test, a laboratory test involving
seroreactions (precipitin reaction, agglutination, complement
fixation, etc.), especially one measuring serum antibody titer. |
|
serologic test for syphilis, any test for
serum antibodies indicative of Treponema pallidum infection.
There are two types: nontreponemal antigen tests detect
antibodies to substance (reagin) derived from host tissues, now
known to consist of the phospholipids cardiolipin and lecithin;
they originated with the Wassermann test and are now represented
by the VDRL and RPR (rapid plasma reagin) tests. Treponemal
antigen tests detect specific antitreponemal antibodies; they
originated with the TPI (T. pallidum immobilization) test and
are now represented by the DFA-TP (direct fluorescent
antibody–T. pallidum) test, the FTA-ABS (fluorescent treponemal
antibody absorption) test, the MHA-TP (microhemagglutination
assay–T. pallidum), and assays using ELISA (enzyme-linked
immunosorbent assay) methods. The term “serologic tests for
syphilis” is occasionally used with reference only to
nontreponemal antigen tests. |
|
serum bactericidal activity test, a type of
antimicrobial susceptibility test for determining, by serial
dilution, the titer of serum (and antimicrobial in serum) that
has effective serum bactericidal activity (see under activity).
Called also Schlichter t. |
|
serum gastrin test, any test that measures
blood levels of gastrin; see fasting serum gastrin, under
gastrin. |
|
serum neutralization test,
neutralization t. |
|
set test, a screening tool for the presence
of dementia. |
|
sex chromatin test, (for determination of
chromosomal sex) examination of somatic cells for presence of a
Barr body at the periphery of the nucleus; an index of the
presence of two X chromosomes, as in a normal XX female, but
also giving a positive result with certain chromosomal
anomalies. Called also buccal smear t.. |
|
shadow test, retinoscopy. |
|
sham feeding test, (for assessment of
completeness of a vagotomy) an appetizing meal is served and
chewed but not swallowed, stimulating gastric acid secretion
solely by vagal pathways; if vagotomy has been successful, there
will be no acid secretion. |
|
sheep cell agglutination test, any
agglutination test using sheep red blood cells, such as the
Rose-Waaler test. |
|
short increment sensitivity index
test, see under index. |
|
shuttle walk test, shuttle
walking test, an exercise test for cardiac function in which the
person walks laps (shuttles) at least 10 meters long on a flat,
nonslippery surface, keeping pace with audio signals; there are
different levels of difficulty in which the patient walks faster
until the point of becoming breathless. |
|
Sia test, (for macroglobulinemia) a simple
screening test performed by adding a drop of serum to 10 to 100
mL of cold distilled water; a positive reaction is indicated by
the formation of a heaving cloud of precipitate at the bottom of
the container. It is not diagnostic, because it may be positive
in other conditions, as in rheumatoid arthritis. |
|
sickling test, a method for demonstrating
hemoglobin S and sickling in erythrocytes, particularly in the
heterozygous state, by reducing the environmental oxygen around
them. It may be done by simply sealing a drop of blood under a
coverslip or may be speeded up by adding 2 per cent sodium
metabisulfite or sodium dithionite to the preparation. |
|
sign test, a nonparametric statistical test
based on a null hypothesis that by chance the experimental group
should outperform the control group for half the outcome
variables and vice versa. Results are scored as a series of
pluses and minuses awarded to the experimental group depending
on its performance relative to that of the control group, a
binomial distribution of scores with p= 0.5 being expected under
the null hypothesis. |
|
signed rank test, a nonparametric
statistical test for ordinal data, comparing two populations of
data by examining the differences between matched pairs in the
two populations. It is based on the signed rank statistic,
calculated by arranging all samples in order without regard to
which population they are drawn from, identifying pairs,
assessing the difference in rankings for the members of each
pair, and summing these differences for all pairs. If the null
hypothesis is true and there is no difference between the two
populations, the median difference in rankings between matched
pairs in the population approximates 0. Called also Wilcoxon
signed rank t. |
|
Sims test, Sims-Huhner test,
postcoital t. |
|
single breath test, single breath
oxygen test, nitrogen washout t., single breath. |
|
SISI test, see short increment
sensitivity index, under index. |
|
skin test, any test in which an antigen is
applied to the skin in order to observe the response of the
patient, described according to method of application, such as
patch tests, scratch tests, and intradermal tests. Skin tests
are used to determine prior exposure or immunity to an
infectious disease (e.g., tuberculin test), to identify
allergens producing allergic reactions, and to assess ability to
mount a cellular immune response (using a battery of antigens
that give positive test results in most normal individuals). |
|
skin window test, Rebuck skin
window technique. |
|
smear test, Papanicolaou t. |
|
Snellen test, (for pretended blindness in
one eye) the patient is requested to look at alternate red and
green letters; the admittedly sound eye is covered with a red
glass and if the green letters are read, evidence of fraud is
present.determination of visual acuity by means of Snellen test
types. |
|
sniff test, (for paralysis of one side of
the diaphragm) the patient sniffs under radiographic
examination; with paralysis of part of the diaphragm, the
paralyzed half is seen to rise and the intact half to descend. |
|
Solera test, (for thiocyanates) saturate
filter paper with 0.5 per cent starch paste containing 1 per
cent of iodic acid; dry and preserve as test paper. A piece of
this paper moistened with saliva will turn blue if thiocyanate
is present. |
|
solubility test, see bile
solubility t. |
|
sorting test, (for assessing abstract
thinking) the patient must arrange objects or cards into groups
based on some abstract relationship. Schizophrenics and patients
with cortical lesions show impaired performance. |
|
soybean test, urease t. (def. 1). |
|
spavin test, (for spavin in horses) the limb
with the hock is held up and bent sharply; the horse is then
started suddenly, and in cases of spavin the first steps are
very lame. Called also hock t. |
|
specific gravity test, see specific tests,
including Fishberg concentration t. and urine concentration t. |
|
sperm agglutination test, (for male factor
infertility) any of various tests for presence of antisperm
antibodies as a cause of infertility, based on the fact that
large multivalent isotypes such as IgM or secretory IgA may be
able to cross-link and agglutinate spermatozoa that have such
antibodies. Serum or seminal plasma is mixed with a known
concentration of sperm; immunoglobulins in the mixture then
begin agglutinating the sperm. After a given period of time at
370C, the amount of agglutination is assessed. |
|
sperm–cervical mucus contact
test, SCMC t. |
|
sperm immobilization test, (for male factor
infertility) a test for antisperm antibodies as a cause of
infertility, based on the fact that spermatozoa with such
surface antibodies lose their ability to move if complement is
present (as it normally is in the female reproductive tract).
Serum from the patient is incubated with motile sperm and
complement is added. After one hour the mixture is checked to
calculate the percentage of formerly motile sperm that can no
longer move; a 50 per cent reduction in motility is a positive
result for presence of antisperm antibodies. Called also Isojima
t. |
|
sphenopalatine test, the sphenopalatine
ganglion is anesthetized with Novocain in order to determine
whether the efferent current motivating a symptom is routed
through either sphenopalatine ganglion, and if so, whether the
left one or the right one. |
|
STA test, standard tube agglutination test,
(for brucellosis) a serologic test using Brucella abortus
antigens to detect infections with B. abortus, B. melitensis,
and B. suis. |
|
Stanford-Binet test, a
modification of the Binet test, translated, adapted, and
standardized on children in the United States. |
|
starch test, see iodine t. (def.
1). |
|
station test, Romberg t. |
|
Staub-Traugott test, see under
effect. |
|
Stein test, (for disease of the labyrinth)
inability to stand on one foot with the eyes shut indicates
disease of the labyrinth. |
|
Stenger test, (for simulated unilateral
hearing loss) a signal is presented at an intensity less than
the admitted threshold to the affected ear, and a less intense
signal of the same frequency is presented simultaneously to the
unaffected ear. If the subject is feigning a loss of hearing,
the signal in the unaffected ear will not be heard. |
|
stimulation test, a type of challenge or
provocative test used when hypofunction of an endocrine gland is
suspected that cannot be detected by other means; either an
exogenous releasing hormone or some other substance is
administered to stimulate release of the hormone under
investigation and levels of it are subsequently measured to
assess whether the patient had a normal response. |
|
Stoll test, (for estimation of worm burden)
a 24-hour stool specimen is collected and the number of eggs
present in an aliquot is calculated. |
|
Straus biological test, Straus
reaction; see under reaction. |
|
stress tests, any of various
tests that assess cardiovascular health and function after
application of a stress to the heart, usually exercise but
sometimes others such as atrial pacing, the cold pressor test,
or specific drugs. Subjects are monitored
electrocardiographically, symptomatically, by blood pressure and
heart rate, and often by recordings of ventilation and tidal
volume recordings as well as other applicable noninvasive or
invasive methods. See also exercise t's. |
|
strychnine test, see Wenzell t. |
|
Student t-test, t-t. |
|
Stypven time test, a prothrombin test
similar to the (one-stage) prothrombin time, but performed with
Russell viper venom (Stypven) as the thromboplastic agent;
useful in defining deficiencies of blood coagulation factor X.
Called also Russell viper venom t. or time and Stypven time. |
|
submaximal exercise test, an exercise test
halted at a predetermined point that is less than the maximal
exercise capability of the subject, usually at a particular
percentage of the maximal heart rate or after a set time
interval. |
|
sucrose hemolysis test, (for
paroxysmal nocturnal hemoglobinuria) the patient's whole blood
is mixed with isotonic sucrose solution, which promotes binding
of complement to red cells, then incubated and examined for
hemolysis; greater than 10 per cent hemolysis is indicative of
paroxysmal nocturnal hemoglobinuria. |
|
sugar test, see fructose t. and glucose t. |
|
sulfobromophthalein excretion
test, (for liver function)sulfobromophthalein, a dye that in
normal individuals is almost completely cleared from the blood
by the liver, is administered intravenously and its rate of
disappearance from the blood is determined colorimetrically; of
historic interest. |
|
sulfur test, (for protein) the suspected
liquid is heated with an excess of sodium hydroxide and a small
quantity of acetate of lead; if proteins are present, a black
precipitate of lead sulfide is formed. |
|
Sullivan test, (for cysteine) to 1 or 2 mL
of the unknown solution add 1 to 2 drops of a 0.5 per cent
solution of sodium β-naphthoquinone-4-sulfonate and then 5 mL of
a 20 per cent sodium thiosulfate made up in 0.25 normal sodium
hydroxide. A brilliant red color indicates a free thiol group,
demonstrating cysteine rather than cystine. |
|
suppression test, a type of
dynamic test used when hyperfunction of an endocrine gland or
presence of a hormone-secreting tumor is suspected; a substance
is administered that is normally antagonistic to glandular
secretion of a given hormone and hormonal levels are measured to
assess whether they drop in the normal fashion. |
|
susceptibility test,
antimicrobial susceptibility t. |
|
swinging flashlight test, (for
damage to the optic nerve or retina) with the patient's eyes
fixed at a distance and a strong light shining before the intact
eye, a crisp bilateral contraction of the pupil is noted. If
when the light is moved to the affected eye, both pupils dilate
for a short period, but when it is returned to the intact eye,
both pupils contract promptly and remain contracted, this
indicates damage to the optic nerve or retina. See also Marcus
Gunn pupillary phenomenon, under phenomenon. |
|
syphilis test, see serologic t.
for syphilis. |
|
t-test, a statistical hypothesis test based
on the t-distribution (q.v.) used to test for a difference
between the means of two groups. Called also Student t-t.
Written also t test. |
|
taurine test, see Lang t. |
|
Teichmann test, (for blood) the suspected
liquid is put under a coverglass with a crystal of sodium
chloride and a little glacial acetic acid; heat carefully
without boiling and then cool. If blood is present, rhombic
crystals of hemin will appear. |
|
Tensilon test, (for myasthenia gravis) after
administration of Tensilon (edrophonium chloride), the patient's
eye signs (ptosis and extraocular muscle abnormalities) markedly
decrease within two minutes in cases of myasthenia gravis. |
|
Terman test, Stanford-Binet t. |
|
thalleioquin test, (for quinine) a
neutralized solution of the suspected liquid is treated with
chlorine, or bromine water, and then with an excess of ammonia;
a green substance, thalleioquin, will be formed. |
|
thallium stress test, (for
coronary artery disease) stress is placed on the cardiovascular
system by exercising the patient on a treadmill or bicycle
ergometer. Thallous chloride Tl-201 is injected intravenously
when stress is maximal, just prior to exercise cessation.
Immediate (stress) and delayed (redistribution) images are
obtained with a gamma camera (see thallium-201 myocardial
perfusion scintigraphy); then abnormalities of radionuclide
distribution and redistribution are assessed, compared with
electrocardiograms obtained during exercise, and used to
diagnose areas of ischemia and coronary artery disease. In
patients incapable of exercise, stress is induced by injection
of dipyridamole or adenosine. |
|
Thematic Apperception Test, a projective
test in which the subject tells a story based on each of a
series of standard ambiguous pictures; his or her responses
reflect a projection of some aspect of the personality and
current psychological preoccupations and conflicts. |
|
thin layer rapid use epicutaneous
test, TRUE t. |
|
thiocyanate test, see ferric chloride t. and
Solera t. |
|
Thomas test, (for flexion contracture of the
hip) the patient lies supine and flexes one leg to bring the
knee as close to the chest as possible, with the lumbar spine
kept flattened. With normal hip function, the opposite leg will
remain flat on the table; with flexion contracture, the opposite
hip and leg will flex also, with the angle taken approximating
the degree of flexion deformity. |
|
Thormählen test, (for melanin in urine)
treat urine with a solution of sodium nitroprusside, potassium
hydroxide, and acetic acid; if melanin is present, a deep blue
color will form. |
|
thromboplastin generation test, a
test formerly used in the detection of defects in formation of
prothrombinase and hence deficiencies of the factors involved. |
|
Thudichum test, (for creatinine) add to the
suspected substance a dilute solution of ferric chloride; a dark
red color indicates the presence of creatinine. |
|
thumbnail test, (for fractured patella) the
examiner's thumbnail is passed over the subcutaneous surface of
the patella; a fracture will be felt as a sharp crevice. |
|
thyroid function test, any of various
diagnostic procedures measuring the functioning of the thyroid
gland, such as the perchlorate discharge test, protein-bound
iodine test, radioactive iodine uptake test, thyroid-stimulating
hormone test, thyroid suppression test, thyrotropin-releasing
hormone test, triiodothyronine resin uptake test, and
measurement of pertechnetate uptake. |
|
thyroid-stimulating hormone test, thyroid-stimulating hormone
stimulation test, TSH test; a thyroid
function test in which thyrotropin (thyroid-stimulating hormone)
is administered intramuscularly and the thyroid gland is
monitored over time with scintiscanning or radioimmunoassays for
a response or areas of decreased responsiveness. The test was
formerly also much used for determining whether hypothyroidism
was caused by thyroid gland failure or by deficiency in
thyrotropin. Called also TSH stimulation t. |
|
thyroid suppression test, a thyroid function
test; after administration of liothyronine for several days,
radioactive iodine uptake is decreased in normal persons but not
in those with hyperthyroidism. |
|
thyrotropin-releasing hormone test, thyrotropin-releasing
hormone stimulation test, a thyroid function
test that assesses pituitary release of thyrotropin; a bolus of
thyrotropin-releasing hormone is administered and serum
concentrations of thyrotropin are assessed at intervals; if
serum levels do not increase within 30 to 40 minutes, the
pituitary thyrotrophs are dysfunctional. Called also TRH
stimulation t. |
|
tilt test, tilt table test,
measurement of various bodily responses while the patient is
tilted to different angles on a tilt table, usually head up,
such as monitoring of circulatory, cardiac, and neurologic
responses. |
|
tine test, tine tuberculin test, a type of
intradermal tuberculin test; four small tines on a plastic
handle, coated with dip-dried tuberculin, are pressed into the
outer layer of skin on the forearm. The skin is checked 48 to 72
hours later for induration; if the induration around one or more
of the puncture wounds is 2 mm or more in diameter or if there
is vesiculation, the test is considered positive. If positive,
it is usually confirmed with the more specific Mantoux test
(q.v.). |
|
Tizzoni test, (for iron in tissues) treat a
section of tissue with a 2 per cent solution of potassium
ferrocyanide, and then with a 0.5 per cent solution of
hydrochloric acid; the tissue will stain blue if iron is
present. |
|
Tobey-Ayer test, (for sinus
thrombosis) the jugular vein on the side of the suspected
thrombosis is compressed. A rise in spinal fluid pressure should
occur; its absence indicates presence of thrombosis. Called also
Ayer-Tobey t. |
|
tolbutamide test, (for insulinoma) one gram
of tolbutamide is administered intravenously and plasma levels
of glucose and insulin are monitored for 3 hours; prolonged
hypoglycemia with hyperinsulinemia indicates presence of an
insulinoma. |
|
tolerance test, an exercise test to
determine the efficiency of the circulation.a test to determine
the body's ability to metabolize a substance or to endure
administration of a drug. |
|
Tollens, Neuberg, and Schwket
test, (for uronic acid) extract the uronic acid from acidified
urine with ether, add water, evaporate the ether, and perform an
orcinol test. |
|
tone decay test, (for hearing) with an
audiometer; the patient is asked to raise one hand as long as
she or he hears a continuous tone at threshold level and to
lower it when the tone becomes inaudible; whenever the patient
lowers the hand before 60 seconds, the intensity is raised by 5
decibels and the amount of tone decay from the initial threshold
level in decibels is determined. |
|
tourniquet test, (for capillary fragility)
pressure is applied midway between diastolic and systolic for 5
minutes by a manometer cuff; the cuff is released and petechiae
are counted in an area 2.5 cm in diameter, on the inner aspect
of the forearm. A number between 10 and 20 is marginal; above 20
is abnormal. Called also capillary fragility t. and Hess
capillary t.Matas t.Perthes t. |
|
toxigenicity test, (for toxigenic strains of
Corynebacterium diphtheriae) a primary culture is streaked onto
a plate of tellurite agar containing a strip of filter paper
perfused with diphtheria antitoxin. The exotoxin produced by the
bacteria forms a band of precipitation with antitoxin diffusing
from the filter paper. Called also Elek t. |
|
Toynbee test, (for patency of the
auditory tube) the Toynbee maneuver is done, and pressure
changes in the middle ear are monitored. Middle ear negative
pressure or negative pressure followed by ambient pressure
usually indicates normal function of the auditory tube. |
|
TPI test, Treponema pallidum
immobilization t. |
|
trapeze test, (for types of spinal
deformities) when the patient hangs from a trapeze, a spinal
deformity will disappear if it is postural but will remain if it
is structural. |
|
tray agglutination test, a type of sperm
agglutination test in which a small amount of sperm and serum is
mixed on a microscopic tray for examination. Called also Friberg
t. |
|
treadmill exercise test, treadmill stress test,
any of various graded exercise tests in
which the patient walks on an inclined treadmill, which is
generally increased in speed and incline through the test; see
also specific test protocols, e.g., Bruce protocol. Cf. bicycle
ergometer exercise t. |
|
Trendelenburg test, (for
varicosity and condition of heart valves) the leg is raised
above the level of the heart until the veins are empty, and then
quickly lowered. If the veins become distended at once,
varicosity and valve incompetence are indicated.(for gluteus
medius function) the patient, standing erect with back to the
examiner, lifts first one leg and then the other. If when weight
is supported by an affected limb, the pelvis on the sound side
falls instead of rising, this indicates disturbance of the
gluteus medius mechanism, such as deformity of the femoral neck,
dislocation of the hip joint, or weakness or paralysis of the
gluteus medius muscle. Called also Trendelenburg sign. |
|
treponemal antigen test, see
serologic t. for syphilis. |
|
Treponema pallidum complement fixation tests,
nontreponemal antigen serologic tests for
syphilis using complement fixation rather than flocculation as
the indicator reaction. Once widely used to confirm positive
results of flocculation procedures, they have now been replaced
by treponemal antigen tests. |
|
Treponema pallidum immobilization test, TPI
test; the first (1949) treponemal antigen serologic test for
syphilis; live Treponema pallidum was mixed with patient serum
and complement and examined to see what proportion of treponemes
were immobilized by antibodies in the serum. |
|
T3 resin uptake test,
triiodothyronine resin uptake t. |
|
TRH test, TRH stimulation test,
thyrotropin-releasing hormone t. |
|
trichophytin test, (for Trichophyton
infection) a type of intradermal test in which filtrates of the
fungus are injected into infected persons; if a reaction similar
to the tuberculin reaction is produced, the patient is having a
cell-mediated hypersensitivity reaction. |
|
triiodothyronine resin uptake test, T3 resin
uptake test; a thyroid function test, measuring how many sites
on thyroxine-binding globulin (TBG) are occupied by endogenous
triiodothyronine (T3)
and how many sites remain available. An excess of radioactive
exogenous triiodothyronine is added to the sample, followed by
the addition of a resin that also binds T3.
A portion of the radioactive T3
binds to sites on TBG not already occupied by endogenous thyroid
hormones, and the remainder binds to the resin. The amount of
labeled hormones bound to the resin (the triiodothyronine resin
uptake) can be subtracted from the total that was added and the
remainder is the amount that bound to the unoccupied binding
sites on the thyroxine-binding globulin. |
|
triketohydrindene hydrate test, (for free
carboxyl or alpha-amino groups) to a solution of aminoacetic
acid and water, a solution of sodium acid is added, followed by
a solution of triketohydrindene hydrate. The suspected matter is
then added and the mixture is boiled. A violet color indicates a
free carboxyl and alpha-amino group from a protein, peptone,
peptide, or amino acid. |
|
triolein breath test, a breath test for
pancreatic function; the fasting patient is administered
triolein labeled with either carbon 13 or carbon 14 and levels
of labeled carbon dioxide in the exhaled breath are subsequently
measured at regular time intervals; low levels of carbon dioxide
indicate inadequate pancreatic lipase, such as with a pancreatic
disease or cystic fibrosis. |
|
triple test, (for evaluation of breast
masses) the use of physical examination, mammography, and fine
needle aspiration to evaluate palpable breast masses. Results of
each method are given point values of 1 (benign), 2
(suspicious), or 3 (malignant) and the points are totaled; a
total score of 4 or less indicates a probably benign lesion, and
6 or more indicates one that is probably malignant. |
|
Trousseau test, (for bile in urine) iodine
tincture diluted with 10 parts of alcohol is added to urine in a
test tube; a green ring is formed where the liquids touch if
bilirubin is present. |
|
TRUE test, thin layer rapid use epicutaneous
test; a ready-to-use method for patch testing, consisting of a
desiccated mixture of allergen and hydrophilic gel printed on a
mylar backing; after application the gel absorbs water from the
skin and releases allergen. |
|
tryptophan load test, (for vitamin B6
deficiency) a single large dose of tryptophan is administered
orally and a 24-hour urine sample is analyzed for xanthurenic
acid, and sometimes also kynurenine, hydroxykynurenine, and
kynurenic acid. If vitamin B6
deficiency exists, kynureninase activity will be decreased and
these metabolites will accumulate in the urine. |
|
TSH test, TSH stimulation test,
thyroid-stimulating hormone t. |
|
tuberculin test, a skin test for
tuberculosis using any of various different types of tuberculin
and methods of application. See also Heaf t., intradermal
tuberculin t., and tine t. |
|
tuberculosis test, a test for the presence
of Mycobacterium tuberculosis; see tuberculin t. and niacin t. |
|
tube-slide agglutination test, a
type of sperm agglutination test in which sperm and serum are
mixed in a tube and then transferred to a slide for examination. |
|
Tuffier test, in aneurysm, when the main
artery and vein of a limb are compressed, swelling of the veins
of the hand or foot will occur only if the collateral
circulation is free. |
|
tuning fork tests, hearing tests using a
vibrating tuning fork of known frequency as a source of sound.
See Bing t., Rinne t., Schwabach t., and Weber t. (def. 1). |
|
two-stage prothrombin test, two-stage prothrombin time test,
(for prothrombin) the quantity of
prothrombin can be measured after tissue thromboplastin and
excess factor V have converted it to thrombin, by determining
the clotting time of a standard fibrinogen solution to which the
previously generated thrombin has been added. |
|
two step exercise test, Master
“2-step” exercise t. |
|
two-tailed test, a hypothesis
test (q.v.) in which the critical region comprises both tails of
the distribution of the test statistic and the null hypothesis
is tested against a two-sided alternative that includes
deviation from the null hypothesis in both directions. |
|
tyrosine test, see specific tests, including
Hoffmann t., Mörner t. (def. 1), Piria t., Udránszky t. (def.
2), and Wurster t. (def. 2). |
|
Tyson test, (for bile acids in urine) 180 to
240 mL of urine are evaporated to dryness on the water bath. The
residue is extracted with absolute alcohol, and to the extract
12 to 14 volumes of ether are added. The bile acids are
precipitated, then are filtered off, dissolved in water, and the
aqueous solution decolorized with animal charcoal. |
|
Tzanck test, examination of tissue from the
floor of a lesion, in vesicular or bullous diseases, in order to
discover the type of cell present for better diagnosis of the
disease. Multinucleated giant cells are pathognomonic of
varicella, herpes simplex, herpes zoster, and pemphigus. |
|
Udránszky test, (for bile acids) take 1 mL
of a solution of the suspected substance, add a drop of 0.1 per
cent solution of furfurol in water, underlay with strong
sulfuric acid, and cool; if bile is present, a bluish-red color
is formed.(for tyrosine) take 1 mL of the suspected substance in
solution, add a drop of 0.5 per cent aqueous solution of
furfurol, and underlay with 1 mL of concentrated sulfuric acid;
a pink color shows the presence of tyrosine. |
|
Ulrich test, (for albumin) the reagent
consists of saturated solution of sodium chloride, 98 mL;
glacial acetic acid, 2 mL. It must be perfectly clear. Boil a
few mL of this fluid in a test tube, and immediately overlay
with the urine. Albumin and globulin give a white ring at the
zone of contact. |
|
Ultzmann test, (for bile pigments) to 10 mL
of the urine to be tested add 3 or 4 mL of a 1:3 solution of
potassium hydroxide, and an excess of hydrochloric acid; bile
pigments will cause an emerald-green coloration. |
|
unheated serum reagin test, USR test; a
modification of the VDRL test using unheated serum, used
primarily for screening. |
|
uracil test, see Wheeler and
Johnson t. |
|
urea test, see specific tests, including
diacetyl t., Schroeder t., and urease t.(def. 1). See also urea,
methods for, under method. |
|
urea breath test, a breath test for the
presence of Helicobacter pylori in the stomach: the patient is
given an oral dose of urea labeled with carbon 13 (heavy carbon)
or carbon 14 (radioactive carbon). At fixed time intervals the
breath is analyzed for presence of labeled carbon dioxide.
Excessive levels of carbon dioxide indicate presence of H.
pylori, since it is accompanied by bacterial urease that
converts the urea to ammonia and carbon dioxide. |
|
urease test, a test for urea based on the
conversion of urea into ammonium carbonate by the urease of
soybean.(for the production of urease by bacteria) urease test
broth (see under culture medium) is prepared in slants. After
inoculation of the surface and incubation, urease-positive
cultures produce an alkaline reaction (red color) in the medium.
Proteus cultures show an early urease-positive reaction; other
bacteria (such as Salmonella and Shigella) usually have a
delayed response. |
|
Urecholine supersensitivity test, (for
neurogenic bladder) 2.5 mg of Urecholine (bethanechol) is
administered subcutaneously; the bladder is neurogenic if it
exhibits a rise in intravesical pressure more than 15 cm greater
than that of a control. |
|
uric acid test, see specific tests,
including Weidel t. (def. 1). See also uric acid, methods for,
under method. |
|
urine concentration test, under a controlled
diet the specific gravity of the urine should reach 1.18 or more
at certain times. |
|
urochromogen test, see Weisz t. |
|
USR test, unheated serum reagin
t. |
|
Valsalva test, Valsalva maneuver
(def. 2). |
|
Van Slyke test, (for amide nitrogen) nitrous
acid acting on amide nitrogen sets free nitrogen gas, which is
collected and its volume determined.(for urea) treat the sample
with urease, pass the ammonia so formed into N/50 normal acid,
and titrate the excess of acid. |
|
VDRL test, the standard nontreponemal
antigen serologic test for syphilis, a flocculation test on a
slide using heat-inactivated serum and VDRL antigen. Positive
tests are seen in about 70 per cent of cases in primary
syphilis, 100 per cent in secondary syphilis, and 70 per cent in
tertiary syphilis. There is a 20 to 40 per cent false positive
rate. |
|
ventilation test, measurement of
the quantity of air exhaled by a person during a period of
exercise. See also pulmonary function t. |
|
Vitali test, (for alkaloids) evaporate with
fuming nitric acid and add a drop of potassium hydroxide; color
reactions will occur. For atropine the color is violet, turning
to red.(for alkaloids) add sulfuric acid, potassium chlorate,
and an alkaline sulfide; various color reactions will
follow.(for bile pigments) add a few drops of potassium nitrate
in solution and dilute sulfuric acid. The color reactions are
green, followed by blue or red and yellow.(for bile pigments)
add quinine bisulfate in solution and follow with diluted
ammonia solution, sulfuric acid, a crystal of sugar, and
alcohol; a violet color results.(for thymol) distill, and pass
the vapor through a mixture of chloroform and potassium
hydroxide solution; a red color results.(for pus in the urine)
the urine is acidified with acetic acid and filtered. On the
filter paper thus obtained a small quantity of guaiacum is
dropped. The paper will turn a dark blue if pus is present. |
|
vitamin test, see specific tests, including
dark-adaptation t., deoxyuridine suppression t., Friderichsen
t., histidine loading t., and Schilling t. |
|
Vogel and Lee test, (for mercury) add 3 per
cent of hydrochloric acid and concentrate the urine to one fifth
its original volume. Add a piece of clean copper wire. A silvery
film indicates mercury. To confirm, place the wire in a tube
with a plug of gold foil and distill the mercury over onto the
gold. Sublime a crystal of iodine onto the mercury and form the
red iodide of mercury. |
|
Voges-Proskauer test, (for differentiation
of Enterobacteriaceae) a test for the production of
acetylmethylcarbinol from glucose in bacterial cultures. An
appropriate culture is treated with a solution of potassium
hydroxide and creatine. Development of a red color indicates a
positive reaction. Enterobacter, Klebsiella, Pantoea, and
Serratia are V-P positive; Erwinia, Pectobacterium, and Yersinia
are variable; Escherichia and other genera of Enterobacteriaceae
are V-P negative. |
|
von Maschke test, (for creatinine) to the
suspected solution add a few drops of Fehling solution, after
mixing with a cold solution of sodium carbonate; an amorphous,
flocculent precipitate proves the presence of creatinine. |
|
von Pirquet test, Pirquet t. |
|
von Zeynek and Mencki test, (for blood)
precipitate the urine with acetone, extract the precipitate with
acidified acetone, and examine the colored extract under the
microscope for small hemin crystals. |
|
Waaler-Rose test, Rose-Waaler t. |
|
Wada test, (for cerebral dominance of
language function) amobarbital is injected into an internal
carotid artery to produce transient hemiparesis of the
contralateral limbs. Injection into the artery of the hemisphere
dominant for language produces a transient aphasia, into that of
the nondominant hemisphere does not interfere with language
function. |
|
Wagner test, (for occult blood),
see benzidine t. |
|
walking test, an exercise test
used to assess exercise tolerance in very disabled patients by
measuring the distance walked in a set time interval. |
|
Wassermann test, the original (1906)
nontreponemal antigen test for syphilis; see serologic t. for
syphilis. |
|
water deprivation test, a test of the body's
ability to concentrate urine when plasma osmolality is
artificially increased: without fasting, the patient is deprived
of water for at least eight hours. Patient weight and
measurements of plasma and urine osmolalities are obtained
before the test and each hour after the four-hour point. In a
normal individual, the osmolality of the urine should increase
to two to four times that of the plasma with eight hours of
water deprivation. After eight hours, vasopressin is
administered and the patient is allowed to drink as usual; in
normal persons this should increase the urine osmolality no more
than 9 per cent in the first hour; in those with diabetes
insipidus and other abnormalities the osmolality may increase
between 10 and 50 per cent. |
|
water provocative test, drinking
t. |
|
Watson-Schwartz test, a simple qualitative
procedure for differentiating porphobilinogen from urobilinogen
and other Ehrlich reactors, based on the insolubility of
porphobilinogen aldehyde in chloroform and butanol; it is useful
in diagnosis of acute porphyria. |
|
Weber test, (for hearing) the stem of a
vibrating tuning fork is placed on the vertex or midline of the
forehead; if the sound is heard best in the affected ear,
conductive hearing loss is probable; if sound is heard best in
the normal ear, there is probably sensorineural hearing loss.
(F. E. Weber.) |
|
(for indican) boil 30 mL of urine with an equal volume of
hydrochloric acid containing a little nitric acid; cool it, and
shake with ether; if indican is present, the ether will become
red or violet and the froth will be blue. (E. H. Weber.)(for
blood) mix the sample with 30 per cent acetic acid and extract
with ether; to the ether extract add an alcoholic solution of
guaiac and hydrogen peroxide. A blue color indicates blood. (E.
H. Weber.) |
|
Weidel test, (for uric acid) the
substance tested is treated with nitric acid, evaporated, and
moistened with diluted ammonia solution; if uric acid is
present, murexide will be formed, and a purple color is
produced. Called also murexide t.(for xanthine) warm with
freshly prepared chlorine water containing a trace of nitric
acid until gas ceases to be produced; contact with gaseous
ammonia develops a pink or purple color.(for xanthine bodies)
dissolve in warm chlorine water, evaporate, and treat with
diluted ammonia solution; a pink or purple color will form,
changing to violet on the addition of sodium or potassium
hydroxide solution. |
|
Weil-Felix test, (for typhus and
certain other rickettsial diseases) the blood serum of a patient
with suspected rickettsial disease is tested against certain
strains of Proteus vulgaris (OX-2, OX-19, OX-K).The
agglutination reactions, based on antigens common to both
organisms, determine the presence and type of rickettsial
infection. |
|
Weisz test, Weisz permanganate test, (for
urochromogen) to 2 mL of the urine add 4 mL of distilled water
and 3 drops of a 1:1000 solution of potassium permanganate; a
canary yellow color indicates urochromogen. |
|
Welland test, bar-reading t. |
|
Wenzell test, (for strychnine) treat the
suspected material with a solution of 1 part potassium
permanganate in 2000 parts of sulfuric acid; even a small amount
of strychnine will cause color reactions. |
|
Wernicke test, see hemiopic
pupillary reaction, under reaction. |
|
Western blot test, Western blot. |
|
Wetzel test, (for carbon monoxide in blood)
to the blood to be examined add 4 volumes of water and treat
with 3 volumes of a 1 per cent tannin solution. If CO is
present, the blood becomes carmine red; normal blood slowly
assumes a grayish hue. |
|
Weyl test, (for creatinine) to the suspected
solution add a little of a dilute solution of sodium
nitroprusside, and then carefully put in a few drops of a weak
solution of sodium hydroxide; a ruby red color results, changing
to blue on warming with acetic acid.(for nitric acid in the
urine) distill 200 mL of urine with 0.2 part of sulfuric or
hydrochloric acid, receiving the distillate in a potassium
hydroxide solution. If m-phenyldiamine is added, a yellow color
will form; if there is added pyrogallic acid in aqueous solution
with a little sulfuric acid, the color will be brown; but
sulfanilic acid in solution, followed in ten minutes by
naphthylamine hydrochlorate, produces a red tint. |
|
Wheeler and Johnson test, (for uracil and
cytosine) to the unknown solution, gradually add bromine water
until the color is permanent; then add an excess of barium
hydroxide. A purple color indicates presence of either uracil or
cytosine. |
|
Whitaker test, (for resistance of
ureters) a pressure-flow study measuring resistance of the
ureters to a given flow rate of urine by antegrade pyelography
of the renal pelvis and a catheter in the bladder. |
|
Widal test, Widal serum test, (for typhoid
and paratyphoid fevers) a test of serum of patients with
suspected Salmonella infection, for the presence of agglutinins
to O antigens and H antigens of the Salmonella enterica serovars
causing typhoid and paratyphoid fevers. |
|
Wilcoxon rank sum test, rank sum
t. |
|
Wilcoxon signed rank test, signed
rank t. |
|
Wishart test, (for acetonemia) a few drops
of plasma are placed in a small test tube. Enough dry powdered
ammonium sulfate is added to supersaturate, so that at the end
of the test there will still be some of the solid sulfate in the
bottom of the tube. A couple of drops of a fresh solution of
sodium nitroprusside are next added and shaken, and finally 1 or
2 drops of diluted ammonia solution. On shaking, a purple color
develops, a little more slowly than in the case of urine. The
intensity of the color indicates the degree of acetonemia. |
|
Woodbury test, (for alcohol in the urine) to
2 mL of urine 1 mL of sulfuric acid is added, and a crystal of
potassium dichromate; a green color will form. |
|
Wormley test, treat the suspected solution
with an alcoholic solution of picric acid; if a yellow
precipitate forms, the result is positive.treat the suspected
solution with a solution of 1 part iodine and 2 parts potassium
iodide in 60 parts of water; if a colored precipitate forms, the
result is positive. |
|
Wurster test, (for hydrogen peroxide) test
paper is saturated with the solution of
tetramethylparaphenylenediamine; hydrogen peroxide turns it to a
blue-violet color.(for tyrosine) the suspected material is
dissolved in boiling water and a little quinone; formation of a
ruby-red color that changes slowly to brown is a positive
result. |
|
xanthine test, see specific tests, including
Hoppe-Seyler t. (def. 2) and Weidel t. (defs. 2, 3). |
|
d-xylose absorption test, (for malabsorption
syndromes)d-xylose dissolved in water is given orally to a
fasting adult, followed immediately by additional water, and the
amount excreted in the urine during a 5-hour period is
determined. Since poor renal function may also result in low
xylose absorption, blood levels are also determined at two
hours. Less than normal excretion of xylose suggests intestinal
malabsorption. Called also d-xylose tolerance t. |
|
d-xylose breath test, a breath test for
bacterial overgrowth in the intestine; the fasting patient is
administered a dose of d-xylose labeled with carbon 14 and the
amount of radiolabeled carbon dioxide in the breath is measured
at regular time intervals. Excessive levels of carbon dioxide
mean that there are high levels of anaerobic bacteria in the
intestines breaking down the xylose. |
|
d-xylose tolerance test, d-xylose
absorption t. |
|
Young test, (for cataract) on a disk with a
varied number of pinholes in different portions, the patient's
ability to recognize the number of holes is a test of the
integrity of macular function. |
|
z test, a statistical test using normalized
data (z values) to compare differences in proportions between
sets of data or between individual members of different sets of
data. |
|
Zaleski test, (for carbon monoxide in blood)
to 2 mL of blood add an equal volume of water and 3 drops of a
one-third saturated solution of cupric sulfate: if carbon
monoxide is present, the precipitate is brick-red; otherwise it
is greenish brown. |
|
Zeisel test, (for colchicine) the substance
being analyzed is dissolved in hydrochloric acid, boiled with
ferric chloride, and shaken with chloroform; if colchicine is
present, a brown or dark-red layer will form at the bottom. |
|
|