Text and Data Mining valid from 2019-04-04
Received: 18 November 2018
Accepted: 21 March 2019
First Online: 4 April 2019
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the First Affiliated Hospital of Guangxi Medical University. All the participants gave written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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