| deterministic model | <epidemiology> A mathematical model in which the parameters and variables are not subject to random fluctuations, so that the system is at any time entirely defined by the initial conditions chosen. Contrast with a stochastic model. (05 Dec 1998) |
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| induced fit model | A model to suggest a mode of action of enzymes in which the substrate binds to the active site of the protein, causing a conformational change in the protein. Synonym: Koshland-Nemethy-Filmer model. (05 Mar 2000) |
| transition probability model | A model to account for the apparently random variation in cell cycle time between individual animal tissue cells in culture that postulates that transition from G1 to s phase is probabilistic. Contrasts with hypotheses that require the accumulation of critical levels of particular proteins. (18 Nov 1997) |
| KNF model | <abbreviation> Koshland-Nemethy-Filmer model. (05 Mar 2000) |
| Koshland-Nemethy-Filmer model | <biochemistry, chemistry> A model to explain the allosteric form of cooperativity; in this model, in the absence of ligands, the protein exists in only one conformation; upon binding, the ligand induces a conformational change that may be transmitted to other subunits. Synonym: Adair-Koshland-Nemethy-Filmer model, induced fit model. (05 Mar 2000) |
| fluid bilayer model | Generally accepted model for membranes in cells. In its original form, the model held that proteins floated in a sea of phospholipids arranged as a bilayer with a central hydrophobic domain. Although it is now recognised that some proteins are restrained by interactions with cytoskeletal elements and that the phospholipid annulus around a protein may contain only specific types of lipid, the model is still considered broadly correct. (18 Nov 1997) |
| fluid mosaic model | A model used to conceptualise cell membranes, in it, the membranesare described as a structually and functionally asymmetric lipidbilayer studded with embedded proteins that aid in cross-membrane transport. (09 Oct 1997) |
| lock-and-key model | A model used to suggest the mode of operation of an enzyme in which the substrate fits into the active site of the protein like a key into a lock. (05 Mar 2000) |
| logistic model | A statistical model; in epidemiology, a model of risk as a function of exposure to a risk factor. (05 Mar 2000) |
| aid to families with dependent children | Financial assistance provided by the government to indigent families with dependent children who meet certain requirements as defined by the social security act, title IV, in the u.s. (12 Dec 1998) |
| androgen-dependent secretory protease | <enzyme> Glycoprotein from dog prostate; hydrolyzes arginine and lysine-containing amide and ester protease substrates Registry number: EC 3.4.99.- Synonym: ads-protease (26 Jun 1999) |
| antibody-dependent cell cytotoxicity | The phenomenon of antibody-mediated target cell destruction by non-sensitised effector cells. The identity of the target cell varies, but it must possess surface IgG whose fc portion is intact. The effector cell is a "killer" cell possessing fc receptors. It may be a lymphocyte lacking conventional b- or T-cell markers, or a monocyte, macrophage, or polynuclear leukocyte, depending on the identity of the target cell. The reaction is complement-independent. (12 Dec 1998) |
| antibody-dependent enhancement | Enhancement of viral infectivity caused by non-neutralizing antibodies. There are at least two mechanisms known to account for this: mediation by fc receptors (receptors, fc) or by complement receptors (receptors, complement). Either the virus is complexed with antiviral IgG and binds to fc receptors, or virus is coated with antiviral IgM and binds to complement receptors. (12 Dec 1998) |
| aromatic NADH-dependent nitroreductase | <enzyme> See also record for 1-nitroreductase; type I nitroreductase is not inhibited by oxygen Registry number: EC 1.- Synonym: nitrofuran reductase, nitrofurazone reductase, type I nitroreductases, NADH-dependent nitro reductase, nitrofurantoin reductase, p-dinitrobenzene reductase, benznidazole nitroreductase, nifurtimox nitroreductase, oxygen-insensitive NADPH nitroreductase, nitrobenzene nitroreductase (26 Jun 1999) |
| aspartic acid 2-oxoglutarate-dependent dioxygenase | <enzyme> Hydroxylates one aspartic acid residue in the first egf-like unit of factor ix Registry number: EC 1.14.11.- Synonym: aspartate 2-oxoglutarate dioxygenase, asp-2-og-dioxygenase, aspartyl beta-hydroxylase, aspartyl (asparaginyl) beta-hydroxylase (26 Jun 1999) |