Funding for this research was provided by:
National Natural Science Foundation of China (81672842, 81872362)
Taishan Scholars Program of Shandong Province (ts201511096)
Natural Science Foundation of Shandong Province (ZR2017ZC0227)
Received: 3 August 2018
Accepted: 1 March 2019
First Online: 11 March 2019
Ethics approval and consent to participate
: This study was approved by the Medical Ethic Committee of Shandong University (Ji’nan, Shandong, China).
: Not applicable.
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