Funding for this research was provided by:
China Postdoctoral Science Foundation (2017M623371)
National Natural Science Foundation of China (81500308, 81770243, 81470248, 81270102)
grant from Shaanxi Province (2016KTCL03-11)
Text and Data Mining valid from 2018-08-28
Received: 1 May 2018
Accepted: 19 July 2018
First Online: 28 August 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Fourth Military Medical University.
: All authors have approved the final manuscript for publication.
: The authors declare that they have no competing interests.
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