Funding for this research was provided by:
National Natural Science Foundation of China (81471048)
Natural Science Foundation of Shandong Province (ZR2012HL42)
Project of Shandong Province Higher Educational Science and Technology Program (J12LK01)
Doctoral Scientific Research Foundation of Weifang Medical University (2017BSQD01)
Article History
Received: 6 June 2017
Accepted: 18 January 2018
First Online: 6 February 2018
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