Funding for this research was provided by:
Department of Science and Technology of Sichuan Province (NO.2015SZ0028)
Text and Data Mining valid from 2018-04-04
Received: 7 December 2017
Accepted: 22 March 2018
First Online: 4 April 2018
Ethics approval and consent to participate
: This study was approved by the Medical Ethics Committee of West China Hospital of Sichuan University and written informed consent was obtained from the patients.
: Not applicable.
: The authors declare that they have no competing interests.
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