Fundamental aspects of the freezing of cells, with emphasis on mammalian ova and embryos.

摘要: The problem in cryobiology is how to cool cells -196/sup 0/C and return them normal temperatures without killing them. One important factor the presence of a protective additive like glycerol or dimethyl sulfoxide. Mammalian rarely survive freezing below -40/sup its absence. In an additive, survival critically dependent on cooling rate. Supraoptimal rates suboptimal are both damaging. Death at supraoptimal result formation intracellular ice recrystallization during warming. consequence major alterations aqueous solutions produced by formation. chief effects reduction fraction solution remaining unfrozen given temperature increase solute concentration that fraction. introduction molar concentrations greatly reduces frozen electrolytes channels cell interior. Usually, either kills outright it results survivors retain full capacity function. But there possibility some cases may fact be impaired genetically physiologically. All evidencemore » indicates genetic damage does not occur. clear examples which induce nonlethal physiological damage. (ERB)« less