1. Center for Reproductive Medicine, Department of Obstetrics and Gynaecology, NanFang Hospital, Southern Medical University, Guangzhou, Guangdong, P.R. China
2. Department of Biopharmaceutics, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, Guangdong, P.R. China
3. Centre for Women, Children and Reproduction, 924 Hospital of PLA Joint Logistic Support Force, Guilin, P.R. China