1. Department of Microbiology; Miyazaki Medical College; Miyazaki 889-16 Japan
2. Department of Surgery and Urology, Kidney Center; Tokyo Women's Medical College; Shinjuku-ku Tokyo 162 Japan
3. Department of Internal Medicine; Miyazaki Prefectural Hospital; Miyazaki Miyazaki 880 Japan
4. Teijin Institute for Biomedical Research; Hino Tokyo 191 Japan