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

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There's a lag period where if I was just looking for antibodies nothing happens for a while.

这中间存在一段迟滞期,如果只过一会就进行观察,抗体的数量不会发生变化

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There's a lag phase, there's a slow rise to an intermediate level of antibody.

会有迟滞期,在该时期,抗体浓度缓慢到达中间水平

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Why the lag phase at the beginning?

为什么迟滞期在应答初期出现

耶鲁公开课 - 生物医学工程探索课程节选