在低温下保存生命,是一门新科学。1980年我国绵羊冷冻胚胎移植获得成功:在一只母羊的腹内移植三个冷冻胚胎,结果生了三只羊羔。冷冻采用液氮。那为什么要采用液氮冷冻胚胎呢?因为给良种母羊注射激素后,一次能排出多达几十个卵子,受精后就形成几十个胚胎,但一只母羊怀不了这么多的羊羔,而要移植到另一些普通母羊的子宫里去借腹怀胎。但取出的胚胎放久了就会死掉,所以要用冷冻的方法把胚胎放到-196℃的液氮罐里,这时胚胎的新陈代谢几乎等于零,它的生命活动暂时停滞了,胚胎就能长期保存。当解冻后,在适当的温度条件下,它又能恢复原来的生命力。 Saving life at low temperatures is a new science. In 1980, the success of frozen embryo transfer in sheep in China was successful: three frozen embryos were transplanted in the abdominal cavity of one ewes, resulting in three lambs. Frozen liquid nitrogen. So why use liquid nitrogen frozen embryos? Because of the injection of hormones to the elite, once discharged as many as dozens of eggs, fertilization after the formation of dozens of embryos, but an ewe can not count so many lambs, Instead, they should be transplanted to the womb of some other common ewes to borrow their belly. However, the removed embryo will die after a long time, so use the freezing method to put the embryo in liquid nitrogen tank at -196 ℃. At this time, the metabolism of the embryo is almost equal to zero. Its life activity temporarily stagnates and the embryo can Long-term preservation. When thawed, it regains its original vitality under appropriate temperature conditions.