Hiroshi Ohara
Bureau of International Medical Center, International Medical Center of Japan,
1-21-1 Toyama, Shinjuku-ku, Tokyo 162, Japan

Koichiro Fujita
Dept. of Medical Zoology, Faculty of Medicine, Tokyo Medical and Dental Unversity,
1-5-45 Yushima, Bunkyo-ku, Tokyo 113, Japan

Hajime Matsuda
Dept. Mdecial Zoology, Dokkyo Unversity, School of Medicine, Kitakobayashi, Mibu, Tochigi 321-02, Japan

Eitaro Hori
Dept. Mdecial Zoology, Saitama Medical School, 38 Morohongo, Moroyama, Saitama 350-04, Japan