Remember that these cells are relatively large compared to bacteria and so diffusion doesn't occur very quickly over this length scale.

要知道这些细胞相对细菌而言,还是比较大的,扩散作用在这种尺度上,发生得不是那么快

耶鲁公开课 - 生物医学工程探索课程节选

And so in the 1940s, a group of people led by Collier started to develop a large scale production method for making a reliable source of vaccinia virus.

在二十世纪四十年代,科利尔带领一群人开始研究,一种大规模的生产方法,这种方法能制得牛痘病毒的可靠来源

耶鲁公开课 - 生物医学工程探索课程节选