1. Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki 852-8501, Japan
2. Faculty of Environmental Studies, Nagasaki University, Bunkyo 1-14, Nagasaki 852-8521, Japan
3. Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-12-4, Nagasaki 852-8501, Japan