So, it's awkward to have to wait for a cow to get infected before you can vaccinate a population.

在给人们预防接种之前,你只有干等着,直到有一头奶牛感染了病毒才行

耶鲁公开课 - 生物医学工程探索课程节选

So if you want a real milk to drink, go to the cow and tell, "Give me fresh milk."

所以，如果你想喝真正的牛奶了，就去跟牛说，“给我点儿新鲜牛奶吧。”

问上门厨师 - SpeakingMax英语口语达人

One is that you got to get the vaccine from cows, so you got to have an infected cow in order to produce the vaccine.

一是,你若要想从奶牛身上得到疫苗,那就得有一头奶牛感染病毒

耶鲁公开课 - 生物医学工程探索课程节选

The answer is 2200 liters of barley, 526 of olives, 468 of wine--I hope you remember all this; fifteen rams, one fat hog, one cow, and two bulls.

答案是两千二百升大麦,五百二十六个橄榄,四百六十八桶酒--我希望你们全能记住,十五头公羊,一头肥猪,一头母牛和两头公牛

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Now we don't need the cow anymore because you could pass it from one person to another, and pass the immunity from one person to another.

由于它可以在人与人之间传播,就不再需要奶牛了,就可以把免疫力在人与人之间传播

耶鲁公开课 - 生物医学工程探索课程节选

When you would take the fluid from the cow, and you would inject it underneath the skin of a person you wanted to protect, then at that site where you injected it, you would get a lesion that looked like a smallpox or cowpox lesion.

当你从奶牛上得到脓液,并把脓液注射到想受到保护的,人的皮肤下面,然后在你注射的地方,你会看到像天花或者牛痘一样的病变

耶鲁公开课 - 生物医学工程探索课程节选

You'd want to make sure that you separated the virus from all the other parts of cow skin so that your ultimate preparation was enriched in the virus and didn't contain quantities of other things that would be hazardous.

你要保证,你从所有的牛皮组织上分离出病毒,这样最终的制剂产品才会富集病毒,并且不会携带其它物质,这些物质可能带来危险

耶鲁公开课 - 生物医学工程探索课程节选