1. Division of Hematology and Oncology, Department of Internal Medicine, China Medical University Hospital, Taichung 404, Taiwan
2. Division of Hematology and Oncology, Department of Internal Medicine, An Nan Hospital, Tainan 700, Taiwan
3. College of Medicine, China Medical University, Taichung 404, Taiwan
4. Stem Cell Research Laboratory, Department of Medical Research, China Medical University Hospital, Taichung 404, Taiwan