Yaffe H, Bar-On H, Eldor A, Ron M, Sadovsky E
Br J Obstet Gynaecol. 1977 May;84(5):354-6. doi: 10.1111/j.1471-0528.1977.tb12598.x.
THe thromboplastic activity of amniotic fluid was correlated with the lecithin sphingomyelin (L/S) ratio in 59 pregnancies. It was shown that the thromboplastic activity and the L/S ratio in amniotic fluid had a coefficient of correlation of r = --0-73 (P less than 0-004). The thromboplastic activity was estimated by a modified method for prothrombin time, and a time of 113 seconds appeared to correspond to an L/S ratio of 2, in that it was the border line between maturity and immaturity of the fetal lungs. Thirty women were delivered within 24 hours of a sample of amniotic fluid being obtained. In the three patients whose babies developed the respiratory distress syndrome, the thromboplastic activity was estimated as being slower than 113 seconds.
对59例妊娠孕妇的羊水促凝血活性与卵磷脂鞘磷脂（L/S）比值进行了相关性研究。结果表明，羊水促凝血活性与L/S比值的相关系数r = -0.73（P<0.004）。促凝血活性采用改良的凝血酶原时间测定方法进行评估，113秒的时间似乎对应于L/S比值为2，因为它是胎儿肺成熟与未成熟的分界线。在获取羊水样本后的24小时内，有30名妇女分娩。在3例婴儿发生呼吸窘迫综合征的患者中，促凝血活性估计慢于113秒。
