即使在感染你的时候，感冒病毒也会发生变异，而且新的病毒毒株经常出现，以至于当制药商研制出针对其中一种变异的疫苗时，血清已经过时了。

Colds mutate even while they're infecting you, and new strains pop up so often that by the time drug-makers create a vaccine against one variation, the serum is already out of date.

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“我爱你们胜过爱棒球！ ”——《绝命毒师》主演布莱恩·克兰斯顿在接受剧情类最佳男主角奖时，对妻子罗宾和女儿泰勒说。

"I love you more than baseball," Bryan Cranston, speaking to his wife, Robin, and daughter, Taylor, while accepting the award for lead actor in a drama, "Breaking Bad."

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以艾维茵肉鸡为试验动物，研究了垂体肾上腺轴在传染性腔上囊病病毒(IBDV)强毒株攻击时对免疫系统的调节作用。

Avian broilers were used as experimental objects to study the mechanism of the pituitary adrenal axis regulating immune system when being infected with virulent infectious bursal disease virus (IBDV).

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This was not a naturally occurring attenuated virus as used in smallpox, but a virus that was attenuated in the laboratory, basically by propagating it in culture and looking for mutants that were formed as you propagated this virus under different experimental conditions.

这不是在制造天花疫苗时,使用的那种天然减毒病毒,而是一种在实验室中被人工弱化的病毒,基本上是通过在细胞中培养繁殖后,从这些培养出来的病毒中挑选出,不同实验环境下的变异体

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So, it's more effective because it's a live virus but it's a little bit more concerning because it's a live virus as well, in that you trust that it's attenuated but could it convert back to a virulent form or a form that caused a disease.

因此,口服疫苗更加有效,因为它是活性病毒,但又是因为这一点,人们也存有更多顾虑,当它处于减毒状态时你会信任它,但是它会不会转变回,强毒壮态或者致病状态呢

耶鲁公开课 - 生物医学工程探索课程节选