1. Department of Molecular Biosciences, Radiation Effects Research Foundation, Minami ku, Hiroshima, Japan;
2. Department of Statistics, Radiation Effects Research Foundation, Minami ku, Hiroshima, Japan;
3. Department of Hematology, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan;
4. Megumino-oka Nagasaki Genbaku Home Clinics, Nagasaki, Japan;
5. Research Center for Nuclear Weapons Abolition, Nagasaki University, Nagasaki, Japan;
6. Nagasaki Atomic Bomb Casualty Council, Nagasaki, Japan