Funding for this research was provided by:
Beijing Municipal Excellent Talents Foundation (2015000021223ZK27)
Received: 20 August 2018
Accepted: 29 January 2019
First Online: 12 February 2019
Ethics approval and consent to participate
: The study protocol and consent forms were approved on 19 January 2016 by the Institutional Review Board of Peking Union Medical College Hospital. The study has been registered at ClinicalTrials.gov (NCT03011866).
: Not applicable.
: The authors declare that they have no competing interests.
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