1. Department of Urology; Nanfang Hospital; Southern Medical University; Guangdong China
2. Wake Forest Institute for Regenerative Medicine; Wake Forest University Health Sciences; Winston-Salem NC USA
3. Center for Reproductive Medicine; General Hospital; Ningxia Medical University; Ningxia China
4. Key Laboratory of Fertility Preservation and Maintenance; Ministry of Education; Ningxia Medical University; Ningxia China
5. Department of Urology; The First Affiliated Hospital of Jinan University; Guangzhou China