| PVR | peripheral vascular resistance; perspective volume rendering; poliovirus receptor; postvoiding resid... |
|---|---|
| RA | radioactive; ragocyte; ragweed antigen; rapidly adapting [receptors]; reactive arthritis; reciprocal... |
| RLC | residual lung capacity |
| RLO | residual lymphatic output |
| RN | radionuclide; red nucleus; Registered Nurse; registry number; residual nitrogen; reticular nucleus |
| noncompetitive inhibition | <chemistry> A form of enzyme inhibition which cannot be reversed by increasing the amount of substrate in the reaction. (09 Oct 1997) |
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| substrate inhibition | Inhibition of an enzyme activity by a substrate of the reaction catalyzed by that enzyme; often, this type of inhibition occurs at elevated substrate levels in which the substrate is binding to a second, non-active site on the enzyme. (05 Mar 2000) |
| nonreciprocal contact inhibition | <cell biology> Collision behaviour between different cell types in which one cell shows contact inhibition of locomotion and the other does not. An example is the interaction between sarcoma cells and fibroblasts (the former not being inhibited). (18 Nov 1997) |
| density dependent inhibition of growth | <cell culture> The phenomenon exhibited by most normal (anchorage dependent) animal cells in culture that stop dividing once a critical cell density is reached. The critical density is considerably higher for most cells than the density at which a monolayer is formed, for this reason, most cell behaviourists prefer the term density dependent inhibition of growth as this avoids any confusion with contact inhibition of locomotion, a totally different phenomenon that is contact dependent. (12 Jan 1998) |
| inhibition | 1. Arrest or restraint of a process. 2. <psychology> The interference with or prevention of a behavioural or verbal response even though the stimulus for that response is present; in psychoanalysis the unconscious restraining of an instinctual process. Origin: L. Inhibere = to restrain, habere = to hold (04 Jul 1999) |
| inhibition factor | <growth factor> A soluble, nondialysable factor that is produced by sensitised lymphocytes following exposure to a specific antigen. It inhibits macrophage migration and causes adherence. It was originally defined on the basis of inhibition of emigration of mononuclear cells from capillary (haematocrit) tubes, more recently a 13 kD protein with migration inhibitory activity has been isolated. Acronym: MIF Synonym: inhibition factor. (22 Sep 2002) |
| tissue thromboplastin inhibition time | A test used to identify lupus anticoagulant; the thromboplastin source used in the prothrombin test is diluted to increase sensitivity to inhibitors. (05 Mar 2000) |
| end product inhibition | <biochemistry, physiology> The process of the end product of a particular metabolic reaction inhibiting an allosteric enzyme involved in that reaction as the reaction starts again, thus breaking the reaction cycle. (09 Oct 1997) |
| enzyme inhibition theory of narcosis | That narcotics inhibit respiratory enzymes by suppression of the formation of high energy phosphate bonds within the cell. (05 Mar 2000) |
| uncompetitive inhibition | An inhibitory effect on a metabolic function, such as an enzyme, not based on competition for the binding site of the naturally occurring substrate, but on a different effect on the molecule whose function is being inhibited. (05 Mar 2000) |
| feedback inhibition | <biochemistry, physiology> The process of the end product of a particular metabolic reaction inhibiting an allosteric enzyme involved in that reaction as the reaction starts again, thus breaking the reaction cycle. (09 Oct 1997) |
| zone of inhibition | <microbiology> The area of no bacterial browth around an antimicrobial agent in the disk-diffusion test. (09 Oct 1997) |
| lateral inhibition | A simple form of information processing. The classic example is found in the eye, whereby ganglion cells are stimulated if photoreceptors in a well defined field are illuminated, but their response is inhibited if neighbouring photoreceptors are excited (an on field/off surround cell) or vice versa an off field/on surround cell. The effect of lateral inhibition is to produce edge or boundary sensitive cells and to reduce the amount of information that is sent to higher centres, a form of peripheral processing. (18 Nov 1997) |
| leukocyte adherence inhibition test | Test for cell-mediated antitumour immunity and related serum blocking factors based on the finding that leukocytes from cancer patients, but not from controls, when mixed in vitro with antigenic extracts of tumours of the same histological type, undergo a diminution in their normal adherence to glass surfaces. Sera from tumour-bearing patients block the lai reaction of their own leukocytes or those of other patients with the same type of tumour. (12 Dec 1998) |