Funding for this research was provided by:
The National Key Research and Development Program of China (2016YFC0903800)
Text and Data Mining valid from 2018-01-24
Received: 8 October 2017
Accepted: 4 January 2018
First Online: 24 January 2018
Ethics approval and consent to participate
: All subjects provided informed consent. This study was approved by the medical ethics committee of Peking University People's Hospital.
: Not applicable.
: The authors declare that they have no competing interests.
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