1 Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China; College of Pharmacy, Third Military Medical University, Chongqing, China.
2 National Institute for Food and Drug Control, Beijing, China.
3 College of Pharmacy, Third Military Medical University, Chongqing, China.
4 Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China. Electronic address: jszfc@vip.sina.com.