为了避免羊膜穿刺术的危险,Michigan state大学的微生物学教授Harold Miller和Harold Sadoff已经发明了一种孕期检查胎儿先天性缺陷的新方法。本方法是抽取怀孕八个星期或更长时间的妇女的血液,从中分离出滋养层。滋养层即胚胎细胞,它是在母亲的血液中发现的。每二百五十万个红血细胞中大约 To avoid the dangers of amniocentesis, Harold Miller and Harold Sadoff, professor of microbiology at Michigan State University, have invented a new method to check for fetal congenital defects during pregnancy. The method is to take the blood of a woman who has been pregnant for eight weeks or longer and separate the trophoblast from it. The trophoblast, the embryonic cell, is found in the mother’s blood. Approximately every 2.5 million red blood cells