| r factors | A class of plasmids that transfer antibiotic resistance from one bacterium to another by conjugation. (12 Dec 1998) |
|---|---|
| rheumatoid factors | Antibodies in the serum of individuals with rheumatoid arthritis that react with antigenic determinants or immunoglobulins that enhance agglutination of suspended particles coated with pooled human gamma-globulin. Rheumatoid factors also occur in other autoimmune and certain infectious diseases. (05 Mar 2000) |
| chemotactic factors | Chemical substances that attract or repel cells or organisms. The concept denotes especially those factors released as a result of tissue injury, invasion, or immunologic activity, that attract leukocytes, macrophages, or other cells to the site of infection or insult. (12 Dec 1998) |
| chemotactic factors, eosinophil | Cytotaxins liberated from normal or invading cells that specifically attract eosinophils; they may be complement fragments, lymphokines, neutrophil products, histamine or other; the best known is the tetrapeptide ecf-a, released mainly by mast cells. (12 Dec 1998) |
| chemotactic factors, macrophage | Cytotaxins liberated from normal or invading cells that specifically attract macrophages. They may be lymphokines, products of antigen, antibody and complement interactions or other. (12 Dec 1998) |
| growth factors | Proteins involved in cell differentiation and growth.Growth factors are essential to the normal cell cycle, and are thus vital elements in the life of animals from conception to death. Among other things, they mediate foetal development, play a role in maintenance and repair of tissues, stimulate production of blood cells, and, gone awry, participate in cancerous processes. (05 Mar 2000) |
| meteorological factors | The atmospheric phenomena which pertain to climate and weather. (12 Dec 1998) |
| clearing factors | Lipoprotein lipases that appear in plasma during lipaemia and catalyze hydrolysis of triglycerides only when the latter are bound to protein and when an acceptor (e.g., serum albumin) is present, thus "clearing" the plasma. (05 Mar 2000) |
| colicin factors | Plasmids determining the potentiality of a bacterium to produce colicins. They are cytoplasmic elements whose integration into the bacterial chromosome has not been demonstrated except for the col b and col v factors. (12 Dec 1998) |
| colonisation factors | <microbiology> The pili on enteropathogenic forms of E. Coli facilitate adhesion of the bacteria to receptors (probably GM1 gangliosides) on gut epithelial cells and are often referred to as colonisation or adherence factors. Colonisation factor antigens may be plasmid coded, are essential for pathogenicity and are strain specific, for example K88 diarrhoea in piglets), CFAI and CFAII on strains causing similar disease in man. (18 Nov 1997) |
| cord factors | Trehalose-6,6'-dimycolate. A toxic glycolipid of mycobacterium tuberculosis. Induces cellular biochemical disfunction in animals; used as immunoadjuvant. (12 Dec 1998) |
| myogenic regulatory factors | A family of muscle-specific transcription factors which bind to DNA in control regions and thus regulate myogenesis. All members of this family contain a conserved helix-loop-helix motif which is homologous to the myc family proteins. These factors are only found in skeletal muscle. Members include the myod protein (myod protein), myogenin, myf-5, and myf-6 (also called mrf4 or herculin). (12 Dec 1998) |
| coupling factors | Proteins that restore phosphorylating ability to mitochondria that have lost it, i.e., have become "uncoupled" so that oxidation and electron transport no longer produces ATP. Usually termed coupling factor F1, F2, etc. Synonym: C factors. (05 Mar 2000) |
| haematopoietic cell growth factors | These growth factors comprise a family of haematopoietic regulators with biological specificities defined by their ability to support proliferation and differentiation of blood cells of different lineages. Erythropoietin and the colony-stimulating factors belong to this family. Some of these factors have been studied and used in the treatment of chemotherapy-induced neutropenia, myelodysplastic syndromes, and bone marrow failure syndromes. (12 Dec 1998) |
| haemolysin factors | Plasmids controlling the synthesis of haemolysin by bacteria. (12 Dec 1998) |