1. Department of Urology, Peking University People's Hospital, The Second Clinical Medical College of Peking University, Beijing 100044, P.R. China
2. Department of Urology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
3. State Key Laboratory of Membrane Biology, School of Medicine, Tsinghua University, Beijing 100084, P.R. China