Received: 4 October 2018
Accepted: 4 December 2018
First Online: 14 January 2019
Ethics approval and consent to participate
: This study was approved by the medical ethics committee of the Xiangya Hospital of Centre South University (IRB (C) No. 201603055). All procedures performed in studies were in accordance with the ethical standards of our institutional ethical committee. Informed consent was obtained from all individual participants included in the study.
: All patients involved had given informed consent.
: The authors declare that they have no competing interests.
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