1. Division of Pathophysiology Okayama University Graduate School of Health Sciences Okayama Japan
2. Division of Clinical Laboratory Hiroshima Red Cross Hospital & Atomic‐bomb Survivors Hospital Hiroshima Japan
3. Department of General Medicine Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
4. Department of Medicine John A. Burns School of Medicine University of Hawai'i Honolulu Hawaii USA
5. Department of Pathology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
6. Department of Hematology Faculty of Medicine Institute of Medical, Pharmaceutical and Health Sciences Kanazawa University Kanazawa Japan
7. Department of Pathology Tokai University School of Medicine Kanagawa Japan