Funding for this research was provided by:
National Natural Science Foundation of China (81200869, 31070930)
Text and Data Mining valid from 2018-06-28
Received: 29 May 2018
Accepted: 19 June 2018
First Online: 28 June 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Peking Union Medical College Hospital (PUMCH), China.
: Not applicable.
: The authors declare that they have no competing interests.
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