Funding for this research was provided by:
National Natural Science Foundation of China (81472987, 81773441)
Natural Science Foundation of Beijing Municipality (7162094)
National Key Research and Development Program, Ministry of Science and Technology, P.R. China (2016YFC1000501)
Text and Data Mining valid from 2018-11-28
Received: 21 July 2018
Accepted: 13 November 2018
First Online: 28 November 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of Peking University Health Science Centre. All participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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