Text and Data Mining valid from 2019-06-13
Received: 25 January 2019
Accepted: 8 May 2019
First Online: 13 June 2019
Ethics approval and consent to participate
: The study was approved by the Ethics Board of Guangxi Medical University. All the subjects were given the detailed information of this study and had signed in the written consent before enrollment.
: Not applicable.
: The authors declare that they have no competing interests.
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