1. Department of Anorectal Surgery, Gansu Provincial People’s Hospital, Lanzhou, Gansu, China
2. General Hospital of Ningxia Medical University, Yinchuan, Ningxia, China
3. Clinical Research Center for Anorectal Diseases of Gansu Province, Lanzhou, Gansu, China
4. The First Clinical Medicine College, Gansu University of Chinese Medicine, Lanzhou, Gansu, China