| EXELFS | extended electron-loss line fine structure |
|---|---|
| hfs | hyperfine structure |
| LFS | lateral facet syndrome; Li-Fraumeni syndrome; limbic forebrain structure; liver function series |
| MTS | Medicare transaction system; magnetization transfer contrast; methotrexate; multicellular tumor sphe... |
| QSAR | quantitative structure-activity relationship |
| structure activity analysis | Study in which systematic variation in the structure of a compound is correlated with its activity, in an attempt to determine the characteristics of the (receptor) site at which it acts. (18 Nov 1997) |
|---|---|
| structure-activity relationship | The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups. Other factors contributing to structure-activity relationship include chemical reactivity, electronic effects, resonance, and inductive effects. (12 Dec 1998) |
| structure-functionalism | The scientific tradition that stresses the relationship between aphysical structure and its function, for example: the related disciplinesof anatomy and physiology. (09 Oct 1997) |
| structure proteins | Proteins whose role is for structure and support in tissue and within the cell; e.g., the collagens. (05 Mar 2000) |
| quarternary structure | The three-dimensional structure of a complex protein, this especially refers to the way the subunits fit together. (09 Oct 1997) |
| quaternary structure | The three-dimensional structure of a complex protein, this especially refers to the way the polypeptide subunits fit together. (09 Oct 1997) |
| tertiary structure | <biochemistry, chemistry> The third level of structural organisation in a macromolecule. The primary structure of a protein (for example) is the amino acid sequence, the secondary structure is the folding of the peptide chain (alpha helical or beta pleated), the tertiary structure is the way in which the helices or sheets are folded or arranged to give the three dimensional structure of the protein. Quaternary structure refers to the arrangement of protomers in a multimeric protein. (13 Jan 1998) |
| ecosystem structure | The physical and spatial aspects of an ecosystem that are contributed by the biotic composition. Biotic composition is generally determined by the collective physiognomy of the dominant plants, including life forms, vertical stratification, and size. (09 Oct 1997) |
| tuboreticular structure | Tubules 20-30 nm in length that lie within cisterns of smooth endoplasmic reticulum; observed in connective tissue diseases such as SLE, and in various cancers and virus infections. (05 Mar 2000) |
| fine structure | <pathology> General term to describe the level of organisation that is below the level of resolution of the light microscope. In practice, a shorthand term for structure observed using the electron microscope, although other techniques could give information about structure in the sub micrometre range. (18 Nov 1997) |
| fine structure mapping | A technique of DNA mapping which makes use of extremely rare recombination events where the crossing over occurs between two genes or two alleles of a gene that are only a few nucleotides apart. (09 Oct 1997) |
| acetoacetyl-acyl carrier protein synthase | <enzyme> E coli enzyme, that catalyses condensation of malonyl-acyl carrier protein plus acetyl-acyl carrier protein; not inhibited by cerulenin Registry number: EC 2.3.1.- Synonym: acetoacetyl-acp synthase (26 Jun 1999) |
| acid soluble spore protein | <molecular biology> A DNA binding protein in the spores of some bacteria, thought to stabilise the DNA in an A configuration, so protecting it from cleavage by enzymes or UV light. (18 Nov 1997) |
| acute-phase protein | <haematology> These plasma proteins (in addition to fibrinogen) increase 25% or more in response to inflammation and injury are under direct control of interleukin-6 (IL-6) (hepatocyte-stimulating factor). Other proteins which increase are ceruloplasmin, C3 and C4 which increase 50% or more; alpha-1 acid glycoprotein, alpha-1 antitrypsin, haptoglobin and fibrinogen (the major determinant of viscosity 1 ) which increase two- to fourfold; C-reactive protein (CRP) and serum amyloid A which increase several hundred-fold. Despite long-held clinical opinion to the contrary, available data indicate that neither ESR nor measurement of specific acute-phase reactants are useful in excluding underlying infection or inflammation regardless of the pretest probability. These proteins are secreted into the blood in increased or decreased quantities by hepatocytes in response to trauma, inflammation, or disease. They can serve as inhibitors or mediators of the inflammatory processes. Certain acute-phase proteins have been used to diagnose and follow the course of diseases or as tumour markers. See also: amyloid, c-reactive protein, erythrocyte sedimentation rate, viscosity. (25 Jun 1999) |
| acyl-(acyl-carrier-protein)-phospholipid acyltransferase | <enzyme> Catalyses the formation of phosphatidylethanolamine from acyl-acyl carrier protein and 2-acyl-sn-glycero-3-phosphoethanolamine Registry number: EC 2.3.1.40 Synonym: 2-acyl-gpe acyltransferase, 2-acylglycerophosphoethanolamine acyltransferase (26 Jun 1999) |