1. Laboratory for Clinical Investigation, Osaka University Hospital, 2-15, Yamada-oka, Suita, Osaka 565-0871, Japan
2. Division of Laboratory Science, Course of Health Science, Graduate School of Medicine, and
3. Department of Clinical Laboratory Science, School of Allied Health Sciences Faculty of Medicine, Osaka University, 1-7 Yamada-oka, Suita, Osaka 565-0871, Japan