| macrophage inhibition factor | <cytokine> A group of lymphokines (including a 14 kD glycoprotein) produced by activated T lymphocytes that reduces macrophage mobility and probably increases macrophage macrophage adhesion. (18 Nov 1997) |
|---|---|
| radiation weighting factor | In radiation protection, a factor weighting the absorbed dose of radiation of a specific type and energy for its effect on tissue. See: equivalent dose. (05 Mar 2000) |
| maise factor | <molecular biology, plant biology> A naturally occurring cytokinin, originally isolated from maize seeds. Its riboside is also a cytokinin. (18 Nov 1997) |
| mammotropic factor | <protein> Pituitary lactogenic hormone (23 kD) Synthesised on endoplasmic reticulum bound ribosomes as preprolactin that has an N terminal signal peptide that is cleaved from the mature form. The conversion of preprolactin to prolactin has been much used as an assay for membrane insertion. (18 Nov 1997) |
| receptors, atrial natriuretic factor | Cell surface proteins that bind atrial natriuretic factor with high affinity and trigger intracellular changes influencing the behaviour of cells. (12 Dec 1998) |
| receptors, colony-stimulating factor | Cell surface receptors for colony-stimulating factors, local mediators, and hormones that regulate the survival, proliferation, and differentiation of haemopoietic cells. (12 Dec 1998) |
| receptors, granulocyte-colony-stimulating factor | Receptors that bind and internalise granulocyte-colony-stimulating factor. Their mw is believed to be 150 kD. These receptors are found mainly on a subset of myelomonocytic cells. (12 Dec 1998) |
| receptors, granulocyte-macrophage colony-stimulating factor | Receptors that bind and internalise the granulocyte-macrophage stimulating factor. Their mw is believed to be 84 kD. The most mature myelomonocytic cells, specifically human neutrophils, macrophages, and eosinophils, express the highest number of affinity receptors for this growth factor. (12 Dec 1998) |
| receptors, macrophage colony-stimulating factor | Glycoproteins of mw 165 kD which are encoded by the c-fms proto-oncogene. The binding of csf-1 to its receptors activates an intrinsic tyrosine kinase activity resulting in autophosphorylation of the receptors on tyrosine, rapid receptor down-regulation, and phosphorylation of as yet unidentified physiologic substrates that initiate a mitogenic response. (12 Dec 1998) |
| receptors, tumour necrosis factor | Cell surface receptors that bind tumour necrosis factor and trigger changes which influence the behaviour of cells. The two recognised tumour necrosis factor receptors are designated alpha and beta receptors. Both receptors bind both alpha and beta tumour necrosis factors with high affinity, and both are members of the nerve growth factor receptor family. (12 Dec 1998) |
| G factor | The single common variance or factor that is common to (i.e., empirically intercorrelates with) different intelligence tests (general). A substance required for the growth of a specific organism. (05 Mar 2000) |
| Castle's intrinsic factor | A mucoprotein normally secreted by the epithelium of the stomach and that binds vitamin B12, the intrinsic factor/B12 complex is selectively absorbed by the distal ileum, though only the vitamin is taken into the cell. (18 Nov 1997) |
| maturation factor | <biochemistry> Member of the water soluble B vitamin group, important in the proper function of the nervous system and important in proper carbohydrate, protein and fat metabolism. (27 Sep 1997) |
| maturation-promoting factor | <enzyme> A protein kinase that drives both the mitotic and meiotic cycles in all eukaryotic organisms. In meiosis it induces immature oocytes to undergo meiotic maturation. In mitosis it has a role in the G2/M phase transition. Once activated by cyclins, maturation-promoting factor directly phosphorylates some of the proteins involved in nuclear envelope breakdown, chromosome condensation, spindle assembly, and the degradation of cyclins. The catalytic subunit of maturation-promoting factor is protein p34cdc2. Acronym: MPF (12 Dec 1998) |
| reflection factor | <microscopy> The ratio of reflected light from a surface to the incident light. This is sometimes called the coefficient of reflection. Unless especially stated it takes into account both specular and diffuse reflection. (05 Aug 1998) |