1. Department of Basic Medicine, Institute of Stem Cell and Regenerative Medicine, Qingdao University Medical College, Qingdao University, Qingdao, P.R. China.
2. School of Basic Medical Sciences, Weifang Medical University, Weifang, P.R. China.
3. School of Pharmacy, Weifang Medical University, Weifang, P.R. China.