1. There are obviously increased of RL of abnormal pregnant group in umbilical placental extrenity than that of normal pregnant group. Conclusions RL obtained by the umbilical artery transmission line mode is a sensitive index which reflects the change of the placental resistance. There are clinical value in finding abnormal pregnancy.
脐动脉传输线模型测定的胎盘血流阻抗是一项较为敏感的监测指标，可以客观地反映胎盘床血流阻力的变化，在发现异常妊娠方面具有一定的临床价值。
2. Methods Sound signal in fetal extrenity and placental extrenity of umbilical artery were first obtained by color Doppler ultrasound. Then they were imported into computer, the placental resistance、PI and RI were calculated. simullaneousoy umbilical artery Pia、Ria and S/D ratio were measured by color Doppler curve.
分别取脐动脉的胎儿端和胎盘端，利用彩色多普勒超声获得脐动脉多普勒信号，转化为声音信号后输入计算机，并计算胎盘的阻力和搏动指数、阻力指数，同时多普勒频谱中测定脐动脉搏动指数、脐动脉阻力指数、脐动脉血流阻力。