Funding for this research was provided by:
the Science and Technology Bureau of Sichuan province in China (2014SZ0235)
Text and Data Mining valid from 2018-05-15
Received: 9 October 2017
Accepted: 4 April 2018
First Online: 15 May 2018
Ethics approval and consent to participate
: This research is approved by the Ethics Committee of Affiliated Hospital of Luzhou Medical University (The approval number is ky2015017). In addition, the research protocol has been registered in the ExternalRef removed (Identifier: ChiCTR-IOC-15007590, 3rd December, 2015). All participants will sign the written informed consent to participate in the study.
: The authors declare that they have no competing interests.
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