| 2009~ | Professor and Chairman, Department of Hematology, Juntendo University School of Medicine |
| 2004-2009 | Professor and Chairman, Department of Hematology/Oncology, Yamanashi University |
| 2000-2004 | Associate Professor, Department of Hematology, Jichi Medical University |
| 1992-2000 | Assistant Professor, Department of Hematology, Jichi Medical University |
| 1990-1991 | Research Fellow, New York Blood Center |
| 1983-1992 | Clinical Research Fellow, Department of Hematology, Jichi Medical University |
| 1981-1983 | Post-graduate Student, Department of Hematology, Jichi Medical University |