Pigments widely distributed throughout nature ( e.g., heme, bile pigments, cytochromes) consisting of four pyrroles joined in a ring (porphin) structure. They are substitution products of porphin (porphyrin) and comprise several varieties, differing for the most part in the side chains (methyl, ethyl, vinyl, formyl, carboxyethyl, carboxymethyl, etc.) present at the eight available positions on the pyrrole rings. Depending on the nature of the side chains, the prefixes dentero-, etio-, meso-, proto-, etc., are attached to p.; distribution within each class is given by type I, II, III, and IV. P. combine with various metals (iron, copper, magnesium, etc.) to form metalloporphyrins, and with nitrogenous substances.

Medical dictionary. 2011.

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  • porphyrins — porphyrins. См. порфирины. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • porphyrins — n. pl. [Gr. porphyra, purple] Four pyrrole rings associated with various metals forming chlorophyll, hemoglobin, etc …   Dictionary of invertebrate zoology

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  • porphyrins — n. substance found in the protoplasm of plants and animals …   English contemporary dictionary

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  • Porphyrin — Structure of porphine, the simplest porphyrin Heme group of hemoglobin. An …   Wikipedia

  • coloration — colorational, adj. colorationally, adv. /kul euh ray sheuhn/, n. appearance with regard to color arrangement or use of colors; coloring: the bold coloration of some birds. [1605 15; COLOR + ATION] * * * ▪ biology Introduction       in biology,… …   Universalium

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  • Porphyria — This article is about the medical condition. For other uses, see Porphyry (disambiguation). Porphyria Classification and external resources ICD 10 E80.0 E80.2 …   Wikipedia

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