胚胎的性别早在受精时就决定了。The sex of the embryo is predetermined at fertilization.收集母牛胚胎的方法有两种, 一种是直接通过产道, 另一种是施用外科手术.There are two methods of collecting cow embryos -- directly through the birth canal, or surgically.目的: 探索制作小鼠多倍体胚...
As soon as he got inside, the dog shook himself.他一进来，狗就开始摇头摆尾。They stopped you as soon as you deviated from the script.一旦你偏离了剧本的内容，他们就会喊停。As soon as the two chicks hatch, they leave the nest burrow.两只小鸟一出壳就离开了巢穴。...
关节炎的新疗法可能是止痛药之外的另一种选择。New ways to treat arthritis may provide an alternative to painkillers.小剂量的止痛药对于降低体温非常有用。Pain-killers are very useful in small amounts to bring your temperature down.阿司匹林是药性平和的止痛药。Aspirin is a mild a...