Text and Data Mining valid from 2018-03-20
Received: 12 May 2017
Accepted: 9 March 2018
First Online: 20 March 2018
Ethics approval and consent to participate
: Ethical approval was obtained from Kunming Medical University Ethics Review Board. All participants were given detailed information about the study in advance to enable them to give written informed consent to participate.
: Not applicable.
: The authors declare that they have no competing interests.
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