Text and Data Mining valid from 2018-07-24
Received: 23 March 2018
Accepted: 4 July 2018
First Online: 24 July 2018
Ethics approval and consent to participate
: All methods in this study were approved the Institutional Ethics Committee (Institute of Medical Biology, Chinese Academy of Medical Sciences, and Peking Union Medical College) and were in accordance with the Declaration of Helsinki for Human Research of 1974 (last modified in 2000).
: Not applicable.
: The authors declare that they have no competing interests.
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