| association time | Time elasping between a stimulus and the verbalised response to it. (05 Mar 2000) |
|---|---|
| association tract | See: association system. (05 Mar 2000) |
| genetic association | The occurrence together in a population, more often than can be readily explained by chance, of two or more traits of which at least one is known to be genetic. (05 Mar 2000) |
| clang association | Psychic association's resulting from sounds; often encountered in the manic phase of manic-depressive psychosis. (05 Mar 2000) |
| plant association | A grouping of plant species, or a plant community, that recurs across the landscape. Plant associations are used as indicators of environmental conditions such as temperature, moisture, light, etc. (05 Dec 1998) |
| word association tests | Lists of words to which individuals are asked to respond ascertaining the conceptual meaning held by the individual. (12 Dec 1998) |
| New York Heart Association classification | A functional classification to assess cardiovascular disability. Class I: patients with cardiac disease without limitation of physical activity. Ordinary activity does not cause symptoms. Class II: patients with cardiac disease with slight limitation of activity; comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea or angina. Class III: patients with cardiac disease producing marked limitation of activity: comfortable at rest. Less than ordinary physical activity causes symptoms. Class IV: patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms may be present even at rest. (05 Mar 2000) |
| free association | Spontaneous verbalization of whatever comes to mind. (12 Dec 1998) |
| laws of association | Principles formulated by Aristotle to account for the functional relationships between ideas; the law of contiguity (association) proved most useful to experimental psychologists, culminating in modern studies of respondent conditioning. (05 Mar 2000) |
| loosening of association | A manifestation of a severe thought disorder characterised by the lack of an obvious connection between one thought or phrase and the next, or with the response to a question. (05 Mar 2000) |
| Abbe test plate | <equipment> A long, wedge-shaped coverslip about 0.20 mm thick at one end and 0.10 to 0.12 mm at the other end coated chemically with a silver film on which are ruled horizontal lines. at each variation in thickness of 0.01 mm there are vertical lines. By means of oblique illumination and by focusing on different portions of the plate, it is possible to determine the optimum coverslip thickness for any objective and also, for microscopes with drawtubes, the tube length for best objective performance. The approximate freedom from spherical and chromatic aberrations can also be estimated. Small isolated bits of silver near the edges of the lines form good objects for the star test (05 Aug 1998) |
| acetone test | A test for ketonuria; the suspected urine is shaken up with a few drops of sodium nitroprusside, and strong ammonia water is then gently poured over the mixture; if acetone is present, a magenta ring forms at the line of contact; tablets containing sodium nitroprusside and alkali are now more commonly used. (05 Mar 2000) |
| achievement test | A standardised test used to measure acquired learning, e.g., competence in a specific subject area such as reading or arithmetic, in contrast to an intelligence test which is a useful index of potential ability or learning. (05 Mar 2000) |
| acidified serum test | Lysis of the patient's red cells in acidified fresh serum, specific for paroxysmal nocturnal haemoglobinuria. Synonym: Ham's test. (05 Mar 2000) |
| acid loading test | <nephrology> This is a test used in the diagnosis of renal tubular acidosis. The patient takes ammonium chloride capsules for 3 days to acidify the blood (lower blood pH). A sample of the urine and the blood is then collected and the results are interpreted. (27 Sep 1997) |