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Medical Term:


Pronunciation: prō′tă-mēn, -min

Definition: Any of a class of proteins, highly basic because rich in l-arginine and simpler in constitution than the albumins and globulins, etc., found in fish spermatozoa in combination with nucleic acid; the protamines have a histonelike function and are present in mammalian sperm; neutralizes anticoagulant action of heparin; used in the preparation of several long-acting insulin preparations.