1. Department of Internal Medicine, Ito Hospital, Tokyo, Japan.
2. Department of Surgery, Ito Hospital, Tokyo, Japan.
3. Thienpont and Stöckl Wissenschaftliches Consulting GbR, 86643 Rennertshofen (OT Bertoldsheim), Germany.
4. Department of Infection Control and Clinical Laboratory Medicine, Dokkyo Medical University, Tochigi, Japan.