1. Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan
2. Department of Pediatrics, JA Shizuoka Kohseiren Enshu Hospital, Hamamatsu 430-0929, Japan
3. Department of Pediatrics, NHO Mie National Hospital, Tsu 514-0125, Japan
4. Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan