Funding for this research was provided by:
The President Foundation of NanFang hospital,Southern Medical University (2017B022)
Text and Data Mining valid from 2018-07-05
Received: 21 February 2018
Accepted: 22 June 2018
First Online: 5 July 2018
Ethics approval and consent to participate
: Study protocol was approved by the Ethical Committee of the NanFang Hospital, Southern Medical University.
: Not applicable
: The authors declare that they have no competing interests.
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