Figure 1. The effect of QYFE on the estrous cycle in ovariectomized (OVX) rats. EV refers to estradiol valerate, QYFE to Qing Yan Formula 70% ethanol extract. Representative photomicrographs taken at 200-X magnification. (I) OVX rats untreated; (II) Shan; (III) OVX rats treated with estradiol valerate (EV); (IV) OVX rats treated with 2.8g/kg QYFE.