Funding for this research was provided by:
the National Key Clinical Specialist Construction Programs of China  (NO. 649)
Text and Data Mining valid from 2018-06-25
Received: 28 November 2016
Accepted: 18 June 2018
First Online: 25 June 2018
Ethics approval and consent to participate
: All analyses were based on previous published studies, thus no ethical approval and patient consent are required.
: Not applicable.
: All authors declare no competing interests. No competing interests exists in this study due to commercial or other associations (e.g., pharmaceutical stock ownership, consultancy, advisory board membership, relevant patents, or research funding). No competing interests exists in the submission of this manuscript, and the manuscript is approved by all of the authors for publication, all authors that the work described was original research that has not been published previously and is not under consideration for publication elsewhere in whole or in part.
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