Funding for this research was provided by:
National Natural Science Foundation of China (81272651, 81570180, 81472402)
Text and Data Mining valid from 2018-08-21
Received: 26 February 2018
Accepted: 30 July 2018
First Online: 21 August 2018
Ethics approval and consent to participate
: The study procedures were approved by the Ethics Committee of Xijing Hospital (reference numbe: KY-20171981). No consent was needed.
: Not applicable.
: The authors declare that they have no competing interests.
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