1. Department of Microbiology; Sapporo Medical College; Sapporo Hokkaido 060
2. Daiichi Seiyaku Co., Ltd. Research Institute; Edogawa-ku Tokyo 134
3. Department of Internal Medicine, Section 1; Sapporo Medical College; Sapporo Hokkaido 060
4. Division of Animal Experimentation; Sapporo Medical College; Sapporo Hokkaido 060
5. Higashi Nippon Gakuen University, School of Dentistry; Hokkaido 061-02