low picogram levels of the e series prostaglandins , pge1 , pge2 , 19-hydroxy pge1 and 19-hydroxy pge2 , in human semen were analysed by silica capillary column gas chromatography with electron-capture detection after conversion to the methyl ester o-trimethylsilyl derivatives of the corresponding b series prostaglandins .
C0033559
e
C0012472
pge2