1. School of Pharmacy, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University) , Ministry of Education, Yantai University , Yantai , P.R. China
2. Department of Histology and Embryology, Basic Medical College , Binzhou Medical University , Yantai , P.R. China