Funding for this research was provided by:
National Natural Science Foundation of China (81260071)
Guangxi Provincial Education Department Funding (KY2015YB232, KY2016YB342)
Text and Data Mining valid from 2018-11-27
Received: 29 August 2018
Accepted: 26 October 2018
First Online: 27 November 2018
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki principles. It was approved by the Medical Research Ethics Committee of Youjiang Medical College Affiliated Hospital.
: Not applicable.
: The authors declare that they have no competing interests.
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