1. National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders, Shizuoka 420-868, Japan
2. Kanagawa Children's Medical Center, Mutsukawa 2-138-4, Minami-ku, Yokohama 232-8555, Japan
3. National Nishi-Niigata Central Hospital, 1-14-1 Masago, Niigata 950-2085, Japan
4. Gifu Prefectural Gifu Hospital, 4-6-1 Noishiki, Gifu, 500-8717, Japan
5. Chunou Kosei Hospital, 5-1 Wakakusa-dori, Seki 501-3802, Japan
6. Department of Pediatrics, Gifu University School of Medicine, Gifu 500-8705, Japan