Onions are biennials; their life cycle is two years long.

VOA: special.2011.06.28

This is a life cycle of a particular class of viruses called retroviruses.

这里是称为逆转录病毒的一种特殊病毒的,生命周期

耶鲁公开课 - 生物医学工程探索课程节选

So, you would grow these monkey kidney cells in culture, you would add some virus to the culture broth, the cells would become infected, the virus would go through its life cycle.

我们在培养基中培养这些猴肾细胞,然偶加入一些脊髓灰质炎病毒,这样细胞就会被感染,病毒开始不断繁殖

耶鲁公开课 - 生物医学工程探索课程节选

And so she wants to have a visual representation of life's cycle."

VOA: special.2011.06.15

That's the life cycle story.

这就是生命周期。

耶鲁公开课 - 金融市场课程节选

The independent group certifies products and services as environmentally friendly through a life-cycle evaluation - looking at the raw materials and the manufacturing process, transportation and recycling of old products.

VOA: standard.2009.03.30

Hopefully their immune systems will respond to it like the real virus but it won't be capable of replication because we've chemically cross linked it so it can't go through its life cycle.

人体的免疫系统,就会对该病毒产生免疫应答,但灭活的病毒不能复制,因为我们已经对它做了化学处理,使它无法进入生命周期

耶鲁公开课 - 生物医学工程探索课程节选

This picture here, we're going to come back to this later in two weeks when we start talking about vaccines, and we're going to talk about how you make vaccines for viruses and so in doing that we're going to think about the life cycle of a virus.

看这幅图片,我们两周之内还会讲到这一内容,在开讲疫苗的时候,我们要讲讲怎么制作病毒疫苗,那时我们要,讲讲病毒的生命周期

耶鲁公开课 - 生物医学工程探索课程节选