1. Department of Urology, Faculty of Medicine; Kyoto University; Kyoto Kyoto 606-01 Japan
2. Department of Microbiology, Faculty of Medicine; Kyoto University; Kyoto Kyoto 606-01 Japan
3. Osaka Prefectural Public Health Institute; Osaka Osaka 537 Japan
4. Research Institute; International Medical Center of Japan; Shinjuku-ku Tokyo 162 Japan