1. Department of Urology, The Second Affiliated Hospital, Harbin Medical University, Nangang, Harbin, Heilongjiang 150086, P.R. China
2. School of Health Management, Harbin Medical University, Nangang, Harbin, Heilongjiang 150086, P.R. China
3. Department of Urology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China