There's no lag period, and notice that antibody levels start rising right away after the second exposure.

没有迟滞期，注意抗体水平在第二次接触后立即开始上升。

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To accurately assess the level of second-hand smoke exposure, researchers tested for cotinine, which is produced when nicotine is metabolized.

VOA: standard.2010.06.15

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

The response to the second exposure in antigen is different in a couple of ways.

第二次接触相同抗原,免疫系统的应答,在以下几个方面是不同的

耶鲁公开课 - 生物医学工程探索课程节选

The second is exposure to dangerous pesticides used during the conflict.

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The second EPZ, called the ingestion exposure pathway zone, includes residents within a 50-mile-radius from the nuclear reactor.

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Mr. TODOROV: One-second exposure to the two faces is sufficient to form the inference.

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