1. Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan
2. Department of Molecular Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan
3. Department of Mutagenesis, Radiation Biology Center, Kyoto University, Kyoto 606-8501, Japan
4. Department of Environmetrics and Biometrics, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan
5. Department of Radiation Biology, Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki 036-8564, Japan
6. Department of Genetics, Radiation Effects Research Foundation, Hiroshima 732-0815, Japan
7. Radiation Emergency Assistance Center/Training Site, Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831
8. Department of Experimental Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan