| PRD | partial reaction of degeneration; physician relations department; postradiation dysplasia |
|---|---|
| QP | quanti-Pirquet [reaction] |
| QRZ | wheal reaction time [Ger. Qaddel Reaktion Zeit] |
| RC | an electronic circuit containing a resistor and capacitor in series; radiocarpal; reaction center; r... |
| RD | radial deviation; radiology department; rate difference; Raynaud disease; reaction of degeneration; ... |
| cutaneous reaction | The inflammatory reaction in the case of a skin test in a sensitive (allergic) subject. Synonym: cutaneous reaction. Origin: L. Cutis, skin, + reaction (05 Mar 2000) |
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| Prausnitz-Kustner reaction | A test for the presence of immediate hypersensitivity in humans; test serum from an atopic individual is injected intradermally into a normal subject; the normal subject is challenged 24-48 hours later with the antigen suspected of causing the immediate hypersensitivity reaction in the atopic individual. Synonym: P-K test. (05 Mar 2000) |
| precipitin reaction | See: precipitin, precipitin test. (05 Mar 2000) |
| harlequin reaction | Sudden blanching of the lower half of the body of an infant lying on its side, leaving the remaining half of the body the normal pink colour. (05 Mar 2000) |
| cytotoxic reaction | An immunologic (allergic) reaction in which noncytotropic IgG or IgM antibody combines with specific antigen on cell surfaces; the resulting complex initiates the activation of complement which causes cell lysis or other damage, or which, in the absence of complement, may lead to phagocytosis or may enhance T lymphocyte involvement. (05 Mar 2000) |
| Sakaguchi reaction | Guanidines in alkaline solution develop an intense red colour when treated with alpha-naphthol and sodium hypochlorite; a qualitative test for arginine, free or in a protein. (05 Mar 2000) |
| Henle's reaction | Dark brown staining of the medullary cells of the adrenal bodies when treated with the salts of chromium, the cortical cells remaining unstained. (05 Mar 2000) |
| Schardinger reaction | The reduction of methylene blue to methylene white by formaldehyde is rapidly catalyzed by fresh milk but not by boiled milk, the catalyzing agent being xanthine oxidase (Schardinger's enzyme); an example of oxidation in the absence of O2 with an organic hydrogen acceptor (the dye). (05 Mar 2000) |
| Herxheimer's reaction | An inflammatory reaction in syphilitic tissues (skin, mucous membrane, nervous system, or viscera) induced in certain cases by specific treatment with Salvarsan, mercury, or antibiotics; believed to be due to a rapid release of treponemal antigen with an associated allergic reaction in the patient. Synonym: Jarisch-Herxheimer reaction. (05 Mar 2000) |
| Schultz-Charlton reaction | The specific blanching of a scarlatinal rash at the site of intracutaneous injection of scarlatina antiserum. Synonym: Schultz-Charlton phenomenon. (05 Mar 2000) |
| Schultz-Dale reaction | The contraction of an excised intestinal loop (Schultz) or of an excised strip of virginal uterus (Dale) from a sensitised animal (guinea pig) which occurs when the tissue is exposed to the specific antigen. (05 Mar 2000) |
| Schwartzmann reaction | Mis spelling of Shwartzman reaction. (18 Nov 1997) |
| prussian blue reaction | The reaction of potassium ferrocyanide with ferric iron to yield a dark blue precipitate at the sites of the ferric iron. Used to determine ferric iron in tissues, particularly in the diagnosis of disorders of iron metabolism. (12 Dec 1998) |
| xanthoprotein reaction | A qualitative test for proteins; a yellow product is formed by reacting proteins with hot, concentrated nitric acid. (05 Mar 2000) |
| Hill reaction | <plant biology> Reaction, first demonstrated by Robert Hill in 1939, in which illuminated chloroplasts evolve oxygen when incubated in the presence of an artificial electron acceptor (e.g. Ferricyanide). The reaction is a property of photosystem II. (11 Jan 1998) |