1. Microbiology and Immunology Laboratory, College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China
2. Institute of Preventive and Veterinary Medicine and The Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, P.R. China
3. Department of Pharmacy, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China