Article History
Received: 24 February 2018
Accepted: 17 June 2018
First Online: 12 July 2018
Ethics approval and consent to participate
: This study was approved by The Ethics Committee of The Second Xiangya Hospital of Central South University (No. S043). Written informed consent to participate in the study was obtained from each participant.
: Not applicable.
: The authors declare that they have no competing interests.
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