Text and Data Mining valid from 2019-06-03
Received: 1 July 2018
Accepted: 21 May 2019
First Online: 3 June 2019
Ethics approval and consent to participate
: The study protocol was approved by the research ethics committee of the Second Xiangya Hospital of Central South University.
: The written informed consent of the study was obtained from each patient.
: The authors declare that they have no competing interests.
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