Ansevin K D, Williams B J
J Exp Zool. 1979 May;208(2):233-43. doi: 10.1002/jez.1402080211.
Cytoplasmic preparations obtained from late blastulae and early gastrulae of normal R. pipiens eggs contain factors which induce delayed lethal effects when injected into normal eggs at the beginning of cleavage. The same preparations can rescue some defective eggs which occur spontaneously (NS eggs), or are produced experimentally (ES eggs), by relieving the specific developmental syndrome displayed by either type of egg. The syndrome involves abnormal endoderm in which cytolysis is time-programmed. The lethal factors as well as the rescue factors are absent in the normal egg cytoplasm prior to the late blastula stage.
从正常豹蛙卵的晚期囊胚和早期原肠胚获得的细胞质制剂含有一些因子，当在卵裂开始时注入正常卵中时，这些因子会诱导延迟的致死效应。相同的制剂可以挽救一些自发出现（NS卵）或通过实验产生（ES卵）的有缺陷的卵，方法是缓解这两种类型的卵所表现出的特定发育综合征。这种综合征涉及异常内胚层，其中细胞溶解是按时间程序进行的。在晚期囊胚阶段之前，正常卵细胞质中不存在致死因子和挽救因子。
