[1] Univ Tsukuba, Dept Urol & Androl, Tsukuba, Ibaraki 305, Japan
[2] Kyushu Univ, Dept Urol, Fukuoka 812, Japan
[3] Sapporo Med Univ, Sch Med, Dept Urol, Sapporo, Hokkaido, Japan
[4] Bayer Yakuhin Ltd, Prod Dev Div, Osaka, Japan
[5] Keio Univ, Sch Med, Dept Urol, Tokyo, Japan