4Kallela H, Haasio J, Korttila K. Comparison ofelta-nolone and propofol in anesthesia for termination of pregnancy[J].Anesth Analg, 1994,79:512-516.
5Lindholm P, Helbo Hansen HS, Jensen B, et al. Effects of fentayl or alfentanil as supplement to propofol anaesthesia for termination of pregnancy[J]. Acta Anaesthesiol Scand, 1994, 38: 545 -549.