| surface-active agent | Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics. (12 Dec 1998) |
|---|---|
| cationic | Referring to positively charged ions and their properties. (05 Mar 2000) |
| cationic detergents | Detergent's, such as the amine salts or quaternary ammonium or pyridinium compounds of long-chain fatty acids, that have positively charged groups attached to the larger hydrophobic portions. (05 Mar 2000) |
| cationic protein | <biochemistry> Proteins of azurophil granules of neutrophils, rich in arginine. A chymotrypsin like protease found in azurophil granules is also very cationic as is cathepsin G and neutrophil elastase. Eosinophil cationic protein (21 kD) is particularly important because it damages schistosomula in vitro. (16 Mar 1998) |
| eosinophil cationic protein | <protein> Arginine rich protein (21 kD) in granules of eosinophils, that damages schistosomula in vitro. Not the same as the MBP (major basic protein) of the granules. (18 Nov 1997) |
| active | Characterised by action, not passive, not expectant. (18 Nov 1997) |
| active acetate | <enzyme> Condensation product of coenzyme A and acetic acid, symbolised as CoAS~COCH3; intermediate in transfer of two-carbon fragment, notably in its entrance into the tricarboxylic acid cycle and in fatty acid synthesis. This coenzyme plays a huge role in intermediary metabolism, in which cells synthesise, break down or use nutrient molecules for energy production, growth, etc. Acetyl-coenzyme A synthase is found in bacteria and plants and catalyses the reaction in which acetate enters metabolic pathways and forms acetyl-coenzyme A. Synonym: acetyl-coenzyme A, active acetate. (05 Mar 2000) |
| active aldehyde | Any aldehyde derivative of thiamin pyrophosphate. (05 Mar 2000) |
| active anaphylaxis | Reaction following inoculation of antigen in a subject previously sensitised to the specific antigen, in contrast to passive anaphylaxis. (05 Mar 2000) |
| active biomass | <cell biology> The amount of a given culture that is actively growing. (06 May 1997) |
| active carbon dioxide | Activated carbon dioxide, a complex of N-carboxybiotin (biotin + CO2) and an enzyme; the form in which carbon dioxide is added to other molecules in carboxylations; e.g., to methylcrotonyl-CoA to form beta-methylglutaconyl in the catabolism of leucine, and to acetyl-CoA to form malonyl-CoA. See: acetyl-CoA carboxylase. (05 Mar 2000) |
| active caries | Microbial-induced lesions of teeth that are increasing in size. (05 Mar 2000) |
| active centre | The part of a macromolecule at which a substrate or ligand, upon binding, produces biological activity; for an enzyme, this is the catalytic centre, the site on an enzyme that catalyses the reaction. (05 Mar 2000) |
| active congestion | Congestion due to an increased flow of arterial blood to a part. (05 Mar 2000) |
| active electrode | A small electrode whose exciting effect is used to stimulate or record potentials from a localised area. Synonym: exciting electrode, localizing electrode, therapeutic electrode. (05 Mar 2000) |