Antibiotics are chemicals, usually small organic molecules that will kill micro-organisms like bacteria.

抗生素是一类化学物质,它们通常是小分子有机物,能够杀死细菌这样的微生物

耶鲁公开课 - 生物医学工程探索课程节选

You don't want to just ignore it, but in cases like that, it's usually a small fraction of the total.

你不能直接把它忽略掉,但在像这样的情形下，它一般是。

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