1. Department of Surgery, Affiliated Hospital of Qingdao University, Qingdao, China
2. Department of Anatomy, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
3. Department of Geratology, The 401st Hospital of PLA, Qingdao, China
4. Department of Urology, Affiliated Hospital of Qingdao University, Key Laboratory of Urinary System Diseases, Qingdao, China