1. College of Chemistry and Environmental Science, Hebei University, Baoding, P. R. China
2. Key Laboratory of Medicinal Chemistry and Molecular Diagnosis (Hebei University), Ministry of Education, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding, P. R. China
3. Department of Immunology, School of Basic Medical Science, Hebei University, Baoding 071002, P. R. China