Funding for this research was provided by:
National Natural Science Foundation of China (No. 81672862)
Capital Characteristic Clinical Application Research and Achievement Promotion Project (No. Z171100001017121)
Text and Data Mining valid from 2018-04-23
Received: 21 July 2017
Accepted: 9 April 2018
First Online: 23 April 2018
Ethics approval and consent to participate
: The study was approved by the Clinical Ethics Committee of Peking University Third Hospital. Because this study is a retrospective study, written consent was not obtained from all participants, and the patients’ data were analyzed anonymously. All methods were performed in accordance with the relevant guidelines and regulations.
: The authors declare that they have no competing interests.
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