营养不良或营养不足可使儿童免疫系统虚弱，尤其是在非完全母乳喂养的婴儿中。

A child's immune system may be weakened by malnutrition or undernourishment, especially in infants who are not exclusively breastfed.

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研究也发现严重的睡眠不足扰乱了免疫系统。

Studies have also found that serious sleep deprivation disrupts the immune system.

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记住只要3个晚上睡眠不足免疫系统就平均降低60%的功效。

Consider that your immune system drops by an average of 60% after just three nights of poor sleep.

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Now, if I was a person that was designing a vaccine and I noticed that this was the response that it got, that antibodies were produced, they reached some intermediate level, they started to fall, I would say, "Well I haven't stimulated the immune system enough, let me re-boost, let me give another dose of antigen."

现在,如果我正在研究一种疫苗,我注意到机体会对这种疫苗产生应答,也就是会产生抗体,当抗体浓度达到中等水平后,就开始下降,就可以说,疫苗对免疫系统刺激还不足,我需要提高抗原浓度,让我再把剂量再加大一倍

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