Funding for this research was provided by:
National Natural Science Foundation of China (81471902)
Beijing Health System High-Level Health Technical Talents Cultivation Fund (2013-2-004)
Text and Data Mining valid from 2019-01-25
Received: 17 April 2018
Accepted: 14 January 2019
First Online: 25 January 2019
Ethics approval and consent to participate
: As described in the Methods section, the study was approved by Beijing Anzhen Hospital, Capital Medical University. All participants received detailed information about the study and provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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