Funding for this research was provided by:
Tianjin Health Bureau of Science and Technology Fund Key Projects (16KG160)
Text and Data Mining valid from 2018-08-02
Received: 17 April 2018
Accepted: 27 July 2018
First Online: 2 August 2018
Ethics approval and consent to participate
: The study was approved by the ethics committee for medical research at Tianjin Huanhu Hospital, and written informed consent was obtained from each participant during recruitment.
: Not applicable
: The authors declare that they have no competing interests.
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