Funding for this research was provided by:
Department of Education of Liaoning Province (LC2015029)
Text and Data Mining valid from 2019-02-12
Received: 13 December 2018
Accepted: 30 January 2019
First Online: 12 February 2019
Ethics approval and consent to participate
: This study was approved by the Medical Research Ethics Committee of China Medical University and informed consent was obtained from all patients.
: Not applicable.
: The authors declare that they have no competing interests.
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