1. Department of Bacteriology, School of Medicine, Kanazawa University, Kanazawa 920-8640,1
2. Institute of Anaerobic Bacteriology, Gifu University School of Medicine, Gifu 500-8705,2
3. Nagoyashi-Koseiin Geriatric Hospital, Nagoya 465-8610,3
4. Ogaki Municipal Hospital, Ogaki 503-0864,4 and
5. Yamaguchi Prefectural Hospital, Bofu 747-8511,5 Japan, and
6. Nosocomial Pathogens Laboratory Branch, Hospital Infections Program, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 303336