He had lost the ability to write and was sick most of the time.

VOA: special.2010.04.09

So these organisms like this are abundant in the world around us and our immune system prevents us from getting sick most of the time.

在我们周围充斥着像这样的生物体,而免疫系统在大多数时候能够抵御疾病

耶鲁公开课 - 生物医学工程探索课程节选

So these organisms like this are abundant in the world around us and our immune system prevents us from getting sick most of the time.

在我们周围充斥着像这样的生物体,而免疫系统在大多数时候能够抵御疾病

耶鲁公开课 - 生物医学工程探索课程节选