| spreading factor | <enzyme> Enzyme that degrades hyaluronic acid, found in lysosomes. (18 Nov 1997) |
|---|---|
| stable factor | <chemical> Heat- and storage-stable plasma protein that is activated by tissue thromboplastin to form factor viia in the extrinsic pathway of blood coagulation. The activated form then catalyses the activation of factor x to factor xa. Chemical name: Blood-coagulation factor VII (12 Dec 1998) |
| Steel factor | Murine equivalent of stem cell factor. (18 Nov 1997) |
| stem cell factor | <growth factor> Haemopoietic growth factor 18.6 kD from sequence, found as dimer (35 kD protein, 53 kD in its glycosylated form). Acronym: SCF (18 Nov 1997) |
| nephritic factor | A serum protein (possibly an IgG autoantibody), found in some patients with membranoproliferative glomerulonephritis and hypocomplementemia, which, together with the cofactors of the alternate pathway of complement activation, cleaves the third component of complement (C3). (05 Mar 2000) |
| nerve growth factor | <growth factor> A peptide (13.26 kD) of 118 amino acids (usually dimeric) with both chemotropic and chemotrophic properties for sympathetic and sensory neurons. Found in a variety of peripheral tissues, nerve growth factor attracts neurites to the tissues by chemotropism, where they form synapses. The successful neurons are then protected from neuronal death by continuing supplies of nerve growth factor. It is also found at exceptionally high levels in snake venom and male mouse submaxillary salivary glands, from which it is commercially extracted. Nerve growth factor was the first of a family of nerve tropic factors to be discovered. Amino acids 1-81 show homology with proinsulin. Besides its peripheral actions, nerve growth factor selectively enhances the growth of cholinergic neurons that project to the forebrain and that degenerate in Alzheimer's disease. Acronym: NGF (18 Nov 1997) |
| nerve growth factor antiserum | An antiserum containing antibodies against nerve growth factor; when injected into newborn animals the majority of sympathetic ganglion cells are permanently destroyed, resulting in hypoinnervation of peripheral tissues. Synonym: NGF antiserum. (05 Mar 2000) |
| neural factor | A protein that can induce the formation of notochord tissue in embryos. (05 Mar 2000) |
| neurotrophic factor | A molecule, usually a protein, that will facilitate the growth or repair of nerve cells. (14 Nov 1997) |
| Streptococcus lactis R factor | 10-formylpteroic acid;a folic acid factor for certain bacteria. Synonym: SLR factor, Streptococcus lactis R factor. (05 Mar 2000) |
| neutrophil activating factor | <cytokine> A cytokine that activates neutrophils and attracts neutrophils and T-lymphocytes. It is released by several cell types including monocytes, macrophages, T-lymphocytes, fibroblasts, endothelial cells, and keratinocytes by an inflammatory stimulus. Il-8 is a member of the beta-thromboglobulin superfamily and structurally related to platelet factor 4. Acronym: IL-8 (12 Dec 1998) |
| neutrophil chemotactant factor | <cytokine> A cytokine that activates neutrophils and attracts neutrophils and T-lymphocytes. It is released by several cell types including monocytes, macrophages, T-lymphocytes, fibroblasts, endothelial cells, and keratinocytes by an inflammatory stimulus. Il-8 is a member of the beta-thromboglobulin superfamily and structurally related to platelet factor 4. Acronym: IL-8 (12 Dec 1998) |
| stringent factor | The gene product (an enzyme) that is crucial to the cellular response of decreased ribosome production as a result of amino acid starvation. See: stringent response. (05 Mar 2000) |
| Stuart-Prower factor | <chemical> Storage-stable glycoprotein blood coagulation factor that can be activated to factor xa by both the intrinsic and extrinsic pathways. A deficiency of factor x, sometimes called stuart-prower factor deficiency, may lead to a systemic coagulation disorder. Chemical name: Blood-coagulation factor X (12 Dec 1998) |
| nuclear factor 1 | See: CTF. (18 Nov 1997) |