So we needed to come up with another source, a renewable source, so we turned our attention to embryonic stem cells.

因此，我们需要一种替代材料，一种可以再生的材料，我们注意到了胚胎干细胞胚胎干细胞。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

We'll talk in a minute about stem cells that are involved in generation of blood and they develop and they live in the bone marrow.

我们一会儿要说到,和血细胞再生有关的干细胞,它们发育并储存在骨髓中

耶鲁公开课 - 生物医学工程探索课程节选