Text and Data Mining valid from 2019-01-31
Received: 14 September 2018
Accepted: 17 January 2019
First Online: 31 January 2019
Ethics approval and consent to participate
: The institutional review board and ethic committee of Tianjin Medical University General Hospital approved the ethical, methodological and protocol aspects of this investigation. We confirm that all methods in the current study were carried out in accordance with the relevant guidelines and regulations. All participants in this research provided their written consents.
: Not applicable.
: The authors declare that they have no competing interests.
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