Postgraduate Institute;
Southern Medical University;
Guangzhou 510515;
China;
Department of Urology;
Guangzhou First Municipal People's Hospital;
Guangzhou Medical College;
Guangzhou 510180;
China;
Department of Urology;
Guangdong Provincial Work Injury Rehabilitation Hospital;
Guangzhou 510440;
China;
Department of Urology;
University of Iowa;
Iowa City;
IA 52242;
USA;