1 Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, 100850 Beijing, People's Republic of China.
2 2Department of Preventive Medicine, Medical School of Hunan Normal University, 410078 Changsha, People's Republic of China.
3 3Institute for Environmental Medicine and Radiation Hygiene, School of Public Health, University of South China, 421001 Hengyang, Hunan Province People's Republic of China.
4 4Department of Cellular and Molecular Biology, Beijing Chest Hospital, Capital Medical University/Beijing Tuberculosis and Thoracic Tumor Research Institute, 101149 Beijing, China.