Funding for this research was provided by:
National Natural Science Foundation of China (31670365, 31470415, 81273957, 81741170, ZR2016HP34, 81670064)
Text and Data Mining valid from 2018-08-09
Received: 17 April 2018
Accepted: 26 July 2018
First Online: 9 August 2018
Ethics approval and consent to participate
: We had complied with the ethics standard for research activity established at Binzhou Medical University. This research work was approved by Ethical Review Committee of Binzhou Medical University, China (Approval number: No. 201704001).
: Not applicable.
: The authors declare that they have no competing interests.
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