Specificity and reproducibility of acetone precipitation in identifying surface-active phosphatidylcholine in amniotic fluid.

[摘要] We show the thoretical and actual variability in the amount of surface-active lecithin precipitated in the acetone-precipitation step of determining lecithin/sphingomyelin (L/S) ratios in the clinical laboratory. Lecithins precipitated may range from 60 to 90% of the total surface-active lecithins present. The range is sufficient to account for the occasional "immature" L/S ratios (less than 2/1) found in amniotic fluid from women bearing mature fetuses.

[学科分类] 过敏症与临床免疫学