Text and Data Mining valid from 2018-10-17
Received: 27 June 2018
Accepted: 25 September 2018
First Online: 17 October 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the First Affiliated Hospital of Anhui Medical University.
: Written informed consent was obtained from each patient.
: The authors declare that they have no competing interests.
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