1. Department of Urology of Medical School and Institute for Medical Sciences; Chonbuk National University, and Research Institute and CTC of Medical Device of Chonbuk National University Hospital; Jeonju 561-712 Republic of Korea
2. Department of Urology; Sungkyunkwan University Medical School; Seoul 135-710 Republic of Korea
3. Department of Physiology; Seoul National University Medical School; Seoul 110-799 Republic of Korea