| resistance factor | <molecular biology> A self-replicating fragment of nucleic acid that confers drug resistance and is transmitted from one bacterium to another via conjugation. (09 Oct 1997) |
|---|---|
| resistance-inducing factor | An agent from normal chick embryos that interferes with multiplication of the avian leukosis-sarcoma virus, and is seemingly an avirulent leukosis virus antigenically related to the avian leukosis-sarcoma virus. (05 Mar 2000) |
| resistance-transfer factor | The transfer gene of the resistance plasmid. (05 Mar 2000) |
| pellagra-preventing factor | A precursor of NAD, that is a product of the oxidation of nicotine. (18 Nov 1997) |
| Von Willebrand factor | Plasma factor involved in platelet adhesion through an interaction with Factor VIII. See: Von Willebrand disease. (18 Nov 1997) |
| von Willebrand factor-degrading protease | <enzyme> A large protease from normal human plasma that degrades vwf at the 842tyr-843met peptide bond Registry number: EC 3.4.24.- Synonym: vwf-cleaving protease (26 Jun 1999) |
| glycotropic factor | A principle in extracts of the anterior lobe of the hypophysis that raises the blood sugar and antagonises the action of insulin; purified pituitary growth hormone produces an identical effect. Synonym: insulin-antagonizing factor. (05 Mar 2000) |
| melanotropin-releasing factor | A hexapeptide similar to oxytocin; it stimulates the release of melanotropin. Synonym: melanotropin-releasing factor, melanotropin-releasing hormone. Origin: melanotropin + L. Libero, to free, + -in (05 Mar 2000) |
| peptide elongation factor tu | A protein found in bacteria and eukaryotic cells which delivers aminoacyl-trna's to the a site of the ribosome. The aminoacyl-trna is first bound to a complex of elongation factor tu containing a molecule of bound GTP. The resulting complex is then bound to the 70s initiation complex. Simultaneously the GTP is hydrolyzed and a tu-GDP complex is released from the 70s ribosome. The tu-GTP complex is regenerated from the tu-GDP complex by the ts elongation factor and GTP. (12 Dec 1998) |
| gonadotropin-releasing factor | <hormone> The peptide hormone that control reproductive function. It produced and released by the hypothalamus and controls the production and release of gonadotrophins from the pituitary gland. It causes the production of luteinising hormone and follicle-stimulating hormone. Synonym: gonadotropin-releasing factor, gonadotropin-releasing hormone, luteinizing hormone/follicle-stimulating hormone-releasing factor, gonadoliberin. Origin: Gonad + L. Libero, to free, + -in (19 Sep 2002) |
| rheumatoid factor | Complex of IgG and anti-igG formed in joints in rheumatoid arthritis. Serum rheumatoid factors are more usually formed from IgM antibodies directed against IgG. (18 Nov 1997) |
| rh factor | An antigen that may or may notbe present on the surface of human bloodcells. If a person's blood has the antigen, their blood type ispositive, if they do not, it is negative. The Rh factor isimportant mainly because if a woman who is Rh- conceives a child who is Rh+, themixing of their bloods in the placenta may provoke an immune reaction in the mother that can cause a life-threatening agglutination of the foetus'blood cells.The Rh factor is so named because it was first identified in Rhesus monkeys. See: ABO blood group. (09 Oct 1997) |
| granulocyte-colony-stimulating factor | <growth factor, haematology, oncology> A glycoprotein of 25 kD containing internal disulfide bonds. It induces the survival, proliferation, and differentiation of neutrophilic granulocyte precursor cells and functionally activates mature blood neutrophils. Among the family of colony-stimulating factors, G-CSF is the most potent inducer of terminal differentiation to granulocytes and macrophages of leukaemic myeloid cell lines. A protein that stimulates the growth and maturation of granulocytes. It is used to promote the recovery of the white cells following chemotherapy. See: colony-stimulating factor. Acronym: G-CSF (12 Dec 1998) |
| granulocyte-macrophage colony-stimulating factor | <growth factor, haematology, oncology> An acidic glycoprotein of mw 23 kD with internal disulfide bonds. It is produced in response to a number of inflammatory mediators by mesenchymal cells present in the haemopoietic environment and at peripheral sites of inflammation. It stimulates the production of neutrophilic granulocytes, macrophages, and mixed granulocyte-macrophage colonies from bone marrow cells and can stimulate the formation of eosinophil colonies from foetal liver progenitor cells. It also has some functional activities in mature granulocytes and macrophages. It is used to promote the recovery of the white blood cells following chemotherapy. Chemical name: Colony-stimulating factor 2 See: colony-stimulating factor. Acronym: GM-CSF (12 Dec 1998) |
| rho factor | <cell biology> Protein factors found in prokaryotes, especially E. Coli, involved in the termination of transcription. Mutations in rho may cause the RNA polymerase to read through from one operon to the next. (23 Aug 1998) |