| EM | early memory; ejection murmur; electromagnetic; electron micrograph; electron microscopy, electron m... |
|---|---|
| GMH | germinal matrix hemorrhage |
| GMRH | germinal matrix related hemorrhage |
| MMP | matrix metalloproteinase; muscle mechanical power |
| MMPI | matrix metalloproteinase specific for collagen type I; Minnesota Multiphasic Personality Inventory |
plaster model
| identity matrix | A square matrix in which the quantities on the diagnonal from top left to bottom right are all equal to 1 and all the other entries are 0. (05 Mar 2000) |
|---|---|
| territorial matrix | The more intensely basophilic matrix in hyaline cartilage surrounding the lacunae in which the cartilage cells lie. Synonym: territorial matrix. (05 Mar 2000) |
| external matrix | The substance occupying the space between the inner and outer membrane of any organelle (e.g., mitochondria) with a double membrane. (05 Mar 2000) |
| extracellular matrix | Any material produced by cells and secreted into the surrounding medium, but usually applied to the noncellular portion of animal tissues. The ecm of connective tissue is particularly extensive and the properties of the ecm determine the properties of the tissue. In broad terms there are three major components: fibrous elements particularly collagen, elastin or reticulin), link proteins (e.g. Fibronectin, laminin) and space filling molecules (usually glycosaminoglycans). The matrix may be mineralised to resist compression (as in bone) or dominated by tension resisting fibres (as in tendon). The basal lamina of epithelial cells is another commonly encountered ecm. Although ecm is produced by cells, it has recently become clear that the ecm can influence the behaviour of cells quite markedly, an important factor to consider when growing cells in vitro: removing cells from their normal environment can have far reaching effects. (18 Nov 1997) |
| extracellular matrix proteins | Macromolecular organic compounds that contain carbon, hydrogen, oxygen, nitrogen, and usually, sulfur. These macromolecules (proteins) form an intricate meshwork in which cells are embedded to construct tissues. Variations in the relative types of macromolecules and their organization determine the type of extracellular matrix, each adapted to the functional requirements of the tissue. The two main classes of macromolecules that form the extracellular matrix are: glycosaminoglycans, usually linked to proteins (proteoglycans), and fibrous proteins (e.g., collagen, elastin, fibronectins and laminin). (12 Dec 1998) |
| acetyl reduction assay | <investigation> A technique for measuring the nitrogen fixation activity in photosynthetic organisms. It uses a flame ionisation detector and a gas chromatography apparatus to determine the reduction of acetylene to ethylene by the enzyme nitrogenase. (06 May 1997) |
| Ames assay | <procedure> One of a number of procedures used to test substances for likely ability to cause cancer that combines the use of animal tissue to generate active metabolites of the substance with a test for mutagenicity in bacteria. (18 Nov 1997) |
| antibiotic assay | <investigation> A test to determine how sensitive a bacterial or fungal strain is to arange of antibiotics bymeasuring the microbes' ability to grow in astandard dilution of each chemical. (09 Oct 1997) |
| assay | <procedure> The determination of the amount of a particular constituent of a mixture or of the biological or pharmacological potency of a drug. (10 May 1997) |
| bandshift assay | <investigation> An assay for proteins, such as transcription factors, that bind specific DNA sequences. A labelled oligonucleotide corresponding to the recognition sequence is incubated with an appropriate nuclear protein extract and run on a nondenaturing acrylamide gel. Oligonucleotides that have been bound by proteins are retarded relative to those that are unbound. (18 Nov 1997) |
| biological assay | <technique> Once a pharmaceutical protein is isolated from the cells in which it was grown, researchers perform tests to measure the protein's biological activity. It must maintain a certain minimal level of biological activity to be used for animal or clinical testing or, later, for market. Researchers also test to confirm that the isolated protein is identical to the desired protein. (21 Mar 1998) |
| radioimmunoprecipitation assay | Sensitive assay using radiolabelled antigens to detect specific antibodies in serum. The antigens are allowed to react with the serum and then precipitated using a special reagent such as protein a sepharose beads. The bound radiolabelled immunoprecipitate is then commonly analyzed by gel electrophoresis. Radioimmunoprecipitation assay (ripa) is often used as a confirmatory test for diagnosing the presence of HIV antibodies. (12 Dec 1998) |
| radioligand assay | <radiobiology> Quantitative determination of receptor (binding) proteins in body fluids or tissue using radioactively labelled binding reagents (e.g., antibodies, intracellular receptors, plasma binders). (12 Dec 1998) |
| radioreceptor assay | A competitive binding assay in which the binder is a membrane or tissue receptor rather than an antibody. (05 Mar 2000) |
| gel retardation assay | A lab technique used to find out if there are proteins binding a fragment of DNA (in a DNA-protein complex) by watching how fast the DNA fragment moves through an electric field and seeing whether it moves slower when a particular protein is also present. (09 Oct 1997) |