Affiliation: | 1. Department of Biochemistry, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-Nishi, Matsudo, Chiba 271, Japan;2. Department of Microbiology, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-Nishi, Matsudo, Chiba 271, Japan;3. Department of Conservative Dentistry, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-Ku, Tokoyo 101, Japan |