| desensitization, allergy | Stimulation of the immune system with gradually increasing doses of the substances to which a person is allergic, the aim being to modify or stop the allergy war (by reducing the strength of the IgE and its effect on the mast cells). This form of treatment is very effective for allergies to pollen, mites, cats, and especially stinging insects (e.g., bees, hornets, yellowjackets, wasps, velvet ants, fire ants). Allergy immunotherapy usually takes 6 months to a year to become effective and shots (injections) are usually required for 3-5 years. (12 Dec 1998) |
|---|---|
| drug allergy | Sensitivity (hypersensitivity) to a drug or other chemical. (05 Mar 2000) |
| immediate allergy | A type I allergic reaction; so called because in a sensitised subject the reaction becomes evident usually within minutes after contact with the allergen (antigen), reaches its peak within an hour or so, then rapidly recedes. See: immediate reaction, anaphylaxis. Compare: delayed allergy. (05 Mar 2000) |
| immunotherapy, allergy | Stimulation of the immune system with gradually increasing doses of the substances to which a person is allergic, the aim being to modify or stop the allergy war (by reducing the strength of the IgE and its effect on the mast cells). This form of treatment is very effective for allergies to pollen, mites, cats, and especially stinging insects (e.g., bees, hornets, yellow jackets, wasps, velvet ants, fire ants). Allergy immunotherapy usually takes 6 months to a year to become effective and shots (injections) are usually required for 3-5 years. (12 Dec 1998) |
| insulin allergy | When a person's body has an allergic or bad reaction to taking insulin made from pork or beef or from bacteria, or because the insulin is not exactly the same as human insulin or because it has impurities. The allergy can be of two forms. Sometimes an area of skin becomes red and itchy around the place where the insulin is injected. This is called a local allergy. In another form, a person's whole body can have a bad reaction. This is called a systemic allergy. The person can have hives or red patches all over the body or may feel changes in the heart rate and in the rate of breathing. A doctor may treat this allergy by prescribing purified insulins or by desensitisation. See: desensitisation. (09 Oct 1997) |
| latent allergy | Allergy that causes no signs or symptoms but can be revealed by means of certain immunologic tests with specific allergens. (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) |
| acid perfusion test | <gastroenterology, investigation> A test used to diagnosis gastrooesophageal reflux disease. This investigation requires that the patient swallow 3 tiny tubes into the stomach. A mixture of hydrochloric acid (like stomach acid) and saline are alternatively injected into the tubes. The patient then reports any symptoms they may have. Some patients may vomit. (13 Nov 1997) |
| acid phosphatase test for semen | A screening test for semen by determining acid phosphatase content; because seminal fluid contains high concentrations of acid phosphatase, while other body fluids and extraneous foreign materials have very low concentrations, high values of acid phosphatase on vaginal aspirate or lavage, or on wash fluid from stains, render positive identification of semen, even if the male is aspermic. (05 Mar 2000) |
| acid reflux test | A test to detect gastroesophageal reflux by monitoring oesophageal pH by an electrode in the distal oesophagus either basally or after acid is instilled into the stomach. (05 Mar 2000) |
| ACTH stimulation test | A test for adrenal cortical function; ACTH administered by continuous intravenous infusion, or intramuscularly, evokes an increase in plasma cortisol in normal persons; in adrenal cortical insufficiency, the expected increase in plasma cortisol is limited or nonexistent. (05 Mar 2000) |