1. Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
2. Department of Cancer Stem Cell Research, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
3. Department of Internal Medicine, Kyushu University Beppu Hospital, Beppu, Japan
4. Department of Medical Education, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan