Text and Data Mining valid from 2018-07-06
Received: 1 February 2018
Accepted: 25 June 2018
First Online: 6 July 2018
Ethics approval and consent to participate
: The study was approved by Ethics Committee of Jining No.1 People’s Hospital, with written informed consents offered by all patients.
: Not applicable.
: The authors declare that they have no competing interests.
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