| RAR | rapidly adapting receptor; rat insulin receptor; retinoic acid receptor; right arm reclining; right ... |
|---|---|
| CR | calculation rate; calculus removed; calorie-restricted; cardiac rehabilitation; cardiac resuscitatio... |
| CRL | cell repository line; Certified Record Librarian; complement receptor location; complement receptor ... |
| DR | degeneration reaction; delivery room; deoxyribose; diabetic retinopathy; diagnostic radiology; digit... |
| ERA | electrical response activity; electroencephalic response audiometry; Electroshock Research Associati... |
| sliding filament hypothesis | The theory that the contracting muscle shortens because two sets of filaments slide past each other. (05 Mar 2000) |
|---|---|
| Starling's hypothesis | The principle that net filtration through capillary membranes is proportional to the transmembrane hydrostatic pressure difference minus the transmembrane oncotic pressure difference; although well established, it is called Starling's hypothesis to distinguish it from Starling's law of the heart. (05 Mar 2000) |
| Neyman-Pearson statistical hypothesis | A formal conjecture about the numerical value of a parameter to be tested exclusively in the light of an immediate set of data without attention to prior knowledge or convictions and ignoring other sets of evidence treated in a similar fashion. The answer is a statement not about whether the hypothesis is true but whether it is an acceptable explanation of the data or should be rejected in favour of another hypothesis. (05 Mar 2000) |
| null hypothesis | The assumption that any observed difference between two samples of a statistical population is purely accidental and not due to systematic causes. (05 Dec 1998) |
| dual recognition hypothesis | An outmoded hypothesis that is known to be incorrect now that the structure of the T-cell receptor is known. The proposal was that viral (and some chemical) antigens were recognised in association with histocompatibility antigens by separate receptors on the T-cell. The generation of cytotoxic T-cells was by association with Class I MHC antigens, of T helper cells by association with Class II MHC antigens. See: altered self hypothesis. (18 Nov 1997) |
| insular hypothesis | An obsolete theory of the origin of diabetes mellitus from destruction or loss of function of the islets of Langerhans in the pancreas. (05 Mar 2000) |
| endosymbiont hypothesis | The hypothesis that semi autonomous organelles such as mitochondria and chloroplasts were originally endosymbiotic bacteria or cyanobacteria. The arguments are convincing and although the hypothesis cannot be proven it is widely accepted. (18 Nov 1997) |
| uniform rate hypothesis | <biology> This states that any two evolving organismal lineages diverge from a common ancestor at a constant rate with respect to each other. (09 Oct 1997) |
| unineme hypothesis | <cell biology, molecular biology> This states that that a chromatid has only one DNA duplex, which goes from one end of the chromatid to the other. (09 Oct 1997) |
| zwitter hypothesis | That an amphoteric molecule (e.g., an amino acid) has, at its isoelectric point, equal numbers of positive and negative charges, thus becoming a zwitterion. (05 Mar 2000) |
| frustration-aggression hypothesis | The theory that frustration may lead to aggression, but that aggression is always the result of some form of frustration. (05 Mar 2000) |
| Lyon hypothesis | <genetics> Hypothesis, first advanced by Lyon, concerning the random inactivation of one of the two X chromosomes of the cells of female mammals. In consequence females are chimaeric for the products of the X chromosomes, a situation that has been exploited in female Negroes (who are heterotypic for isozymes of glucose 6 phosphate dehydrogenase) as a means to confirm the monoclonal origin of papillomas and of atherosclerotic plaques. (20 Mar 1998) |
| acetylcholine receptor antibodies | <neurology, investigation> A test used to measure the amount of antibodies to acetylcholine receptors on nerve endings. This is a diagnostic test for myasthenia gravis. A normal value is no antibodies in the bloodstream. Acetylcholine receptor (AChR) binding autoantibodies (i.e. Antibodies reactive with several epitopes other than the binding site for acetylcholine or alpha-bungarotoxin) are present in approximately 88% of patients with generalised myasthenia gravis, 70% of ocular myasthenia and in approximately 80% of myasthenia gravis in remission. Although serum concentrations of AChR binding autoantibodies do not in general correlate well with severity of weakness, there is typical decrease in concentration as weakness improves with immunosuppressive therapy. AChR blocking autoantibodies (i.e., antibodies reactive with the AChR binding site) are present in about 50% of patients with myasthenia gravis, 30% with ocular myasthenia gravis and 20% of myasthenia gravis in remission, AChR blocking autoantibodies are the only AChR autoantibodies present in about 1% of myasthenia gravis. AChR modulating autoantibodies (i.e., autoantibodies which cross-link AChRs and cause their removal from muscle membrane surfaces) are present in more than 90% of myasthenia gravis and occasionally are the only AchR autoantibodies detectable in mild, recent onset or ocular-restricted myasthenia gravis. Results for AChR modulating autoantibodies can be transiently false-positive due to curare-like drugs used during general anesthesia. AChR autoantibodies of one or more types are found in at least 80% of ocular myasthenia gravis. Although generally absent in neurological conditions other than myasthenia gravis(and consequently unlikely to cause confusion in neurodiagnosis), false-positive results for AChR autoantibodies occasionally occur in primary biliary cirrhosis, tardive dyskinesia, autoimmune thyroiditis, the elderly, amyotrophic lateral sclerosis patients treated with cobra venom and patients with thymoma in the absence of myasthenia gravis. Approximately 1% of patients with rheumatoid arthritis treated with D-penicillamine develop AChR autoantibodies and myasthenia gravis, both of which disappear when the drug is discontinued. Babies born to ~10% of myasthenia gravis mothers have a transient neonatal form of myasthenia gravis that responds well to anticholinesterase therapy and usually remits within 1 month as maternal IgG disappears. (29 Dec 1997) |
| amino acid receptor | <biochemistry> Ligand gated ion channels with specific receptors for amino acid transmitters. An extended protein superfamily that also includes subunits of the nicotinic acetylcholine receptor. (18 Nov 1997) |
| AMPA receptor | <cell biology> Glutamate operated ion channel. See: excitatory amino acid receptor channels. (05 Feb 1998) |