Funding for this research was provided by:
Chinese Academy of Medical Sciences (2017-I2M-3-017)
Education Reform Projects of Peking Union Medical College (015zlgc0706)
The Health Research and Special Projects of China (No. 201002020)
Received: 22 July 2018
Accepted: 10 December 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: All aspects of this study were approved by the Institutional Committee of Science and Research Ethics (IRB number: S-K415). All patients participating gave written informed consent and authorization for use of data.
: Not applicable.
: The authors declare that they have no competing interests.
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