Text and Data Mining valid from 2018-10-05
Received: 3 June 2018
Accepted: 6 September 2018
First Online: 5 October 2018
Ethics approval and consent to participate
: The study was performed with the approval of the ethics committee of the Nanjing Medical University and the written informed consent was obtained from each participant.
: Not applicable.
: The authors declare that they have no competing interests.
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