And in two thousand eight, seventeen people died in Senegal after lead exposure from a battery recycling center.

VOA: special.2009.08.31

One is there's no lag period, notice that antibody levels start rising right away after the second exposure.

第一是没有迟滞期,请注意,抗体浓度迅速上升,在第二次接触抗原时

耶鲁公开课 - 生物医学工程探索课程节选

Well really, the things we've looked at thus far can you do after just a semester of this kind of material and exposure to this particular world.

当结束这样一门课时,你是不是能通过学习和接触计算机科学,也做出我们刚刚看到的这些东西。

哈佛公开课 - 计算机科学课程节选

Because on second exposure there's another population of cells that I haven't mentioned before that remain after the primary exposure and those are called memory cells, they're down here.

因为在再次免疫中,有另外一些细胞,我之前并没有提到过它们,在初次免疫结束后保留下来的细胞,被称为记忆细胞,它们在下面

耶鲁公开课 - 生物医学工程探索课程节选