1. Department of Pediatrics; Hirosaki University Hospital; Hirosaki Japan
2. Department of Nephrology; Kansai Medical University; Hirakata Japan
3. Department of Pediatrics; Kobe University Graduate School of Medicine; Kobe Japan
4. Department of Pathology; Tohoku University Graduate School of Medicine; Sendai Japan
5. Department of School Health Science; Hirosaki University Faculty of Education; Hirosaki Japan