Funding for this research was provided by:
National Natural Science Foundation of China (81471511, 81270753)
the Personnel Training Plan of The Health Care System of Beijing (2013-3-021)
the Talent Development Program of Beijing Chaoyang Hospital (to Wenhui Zhou)
Received: 29 August 2017
Accepted: 15 February 2018
First Online: 2 March 2018
Ethical approval and consent to participate
: Local ethical approval was obtained for the study. All procedures were performed in accordance with ethical standards developed by an institutional and national research committee, and were in compliance with the Helsinki declaration on Human Experimentation.
: Not applicable.
: The authors declare that they have no competing interests.
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