| tissue-specific antigen | A heterogenetic antigen with organ specificity; e.g., in addition to species-specific antigen, kidney of one species contains antigen that is identical to that in kidney of other species. Synonym: tissue-specific antigen. (05 Mar 2000) |
|---|---|
| tumour specific antigen | <immunology, oncology> Antigen on tumour cells detected by cell-mediated immunity. For virus transformed cells TSTA (unlike T antigen) is found to differ for different individual tumours induced by the same virus. May consist of fragments of T antigens exposed at the cell surface. (18 Nov 1997) |
| tumour-specific transplantation antigens | Surface antigen's of DNA tumour virus-transformed cells, which elicit an immune rejection of the virus-free cells when transplanted into an animal that has been immunised against the specific cell-transforming virus. (05 Mar 2000) |
| uridine-specific acid nuclease | <enzyme> Chicken liver enzyme hydrolyzes poly(u) and e. Coli RNA Registry number: EC 3.1.- (26 Jun 1999) |
| fluoroacetate-specific dehalogenase | <enzyme> Acts on fluoroacetamide at 0.1 the rate for fluoroacetate Registry number: EC 3.8.1.- Synonym: fluoroacetate-specific defluorinase, fac dehalogenase (26 Jun 1999) |
| law of specific nerve energies | Each type of sensory nerve ending, however stimulated (electrically, mechanically, etc.), gives rise to its own specific sensation; moreover, each type of sensation depends not upon any special character of the different nerves but upon the part of the brain in which their fibres terminate. Synonym: law of specific nerve energies. (05 Mar 2000) |
| lymphocyte specific protein tyrosine kinase p56(lck) | <enzyme> This enzyme is a lymphoid specific src family tyrosine kinase that is critical for T-cell development and activation. Lck is associated with the cytoplasmic domains of CD4, CD8 and the beta-chain of the il-2 receptor, and is thought to be involved in the earliest steps of tcr-mediated T-cell activation. Registry number: EC 2.7.11.- (12 Dec 1998) |
| abscopal effect | A reaction produced following irradiation but occurring outside the zone of actual radiation absorption. (05 Mar 2000) |
| additive effect | <biochemistry, chemistry> An additive effect is the overall biological effect two chemicals acting together and which is the simple sum of the effects of the chemicals acting independently. Compare: antagonism. (15 Jan 1998) |
| adverse effect | This is an abnormal or harmful effect to an organism caused by exposure to a chemical. It is indicated by some result such as death, a change in food or water consumption, altered body and organ weights, altered enzyme levels, or visible illness. An effect may be classed as adverse if it causes functional or anatomical damage, causes irreversible change in the homeostasis of the organism, or increases the susceptibility of the organism to other chemical or biological stress. A non-adverse effect will usually be reversed when the organism is no longer being exposed to the chemical. (09 Oct 1997) |
| Anrep effect | A small transient positive inotropic effect of abrupt increases of systolic aortic and left ventricular pressures related to recovery from transient subendocardial ischemia (e.g., cold pressor test). (05 Mar 2000) |
| antagonistic effect | This is the consequence of one chemical (or group of chemicals) counteracting the effects of another chemical, the opposing chemicals cancel out each other's effects. (09 Oct 1997) |
| Arias-Stella effect | Focal, unusual, decidual changes in endometrial epithelium, consisting of intraluminal budding, and nuclear enlargement and hyperchromatism with cytoplasmic swelling and vacuolation; may be associated with ectopic or uterine pregnancy. Synonym: Arias-Stella effect, Arias-Stella reaction. (05 Mar 2000) |
| Auger effect | <physics> Transition of an electron in an atom from a discrete electronic level to an ionised continuous level with the same energy. Synonym: autoionisation. (13 Jan 1998) |
| autokinetic effect | In psychology, the apparent drifting about of a small, fixed, spot of light which is being observed in a dark room. (05 Mar 2000) |