Funding for this research was provided by:
Natural Science Foundation of Shandong Province (ZR2015HM034)
Received: 1 August 2018
Accepted: 31 October 2019
First Online: 23 January 2020
: All animal experiments were carried out in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals (publication 86–23, revised in 1986) and the Committee of Yantai University for the Care and Use of Laboratory Animals (Approval number, YTU20140803).
: Not applicable.
: The authors declare that they have no competing interests.