Text and Data Mining valid from 2018-05-17
Received: 17 March 2018
Accepted: 4 May 2018
First Online: 17 May 2018
Ethics approval and consent to participate
: The study was approved by the ethics committee of The First Affiliated Hospital of Nanchang University. It was conducted according to the standards of the Declaration of Helsinki.
: The authors declare that they have no competing interests.
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