【摘要】 本文用低温取代法,研究了金鱼胚胎经两种不同的降温程序冷却到液氮温度后的超微结构图象。研究表明:若金鱼胚胎置入低浓度的抗冻剂溶液,慢速降温到-20℃后再快速浸入液氮,胚胎中有许多大的冰晶形成。这些大冰晶严重地破坏了金鱼胚胎的超微结构。而若将金鱼胚胎置入高浓度的玻璃化溶液中快速浸入液氮,胚胎外溶液可实现玻璃态固化。虽然胚胎内部仍有许多小的冰晶形成,但其体积比慢速降温时小得多,它们对胚胎细胞结构的影响也较小。更多还原

【Abstract】 In the present paper, the ultrastructure images of gold fish （carassius auratus） embryos cooled to LN₂ （liquid nitrogen） temperaturer by two ways are investigated by cryosubstitution. The main conclusions are: 1. When fish embryos in low cryoprotectant concentration solutions are cooled to -20℃ at slow cooling rates and then quenched to LN₂, many large ice-crystals which seriously damage the ultrastructure of the fish embryos are formed inside the embryos. 2. When fish embryos in high concentration vitrification solutions are directly quenched to LN₂, the extra-embryo solutions can be vitrified. Although many ice-crystals are still formed inside the embryos, they are much smaller than those in the slow cooling. The damage of small ice-crystals to the ultrastructure of fish embryos is much weaker than that of large ice-crystals.更多还原