1. State Key Laboratory of Toxicology and Medical Counter Measures, Beijing Institute of Pharmacology and Toxicology, Beijing, P.R. China.
2. State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, P.R. China.
3. School of Public Health and Management, Weifang Medical University, Weifang, P.R. China.