Funding for this research was provided by:
the National Natural Science Foundation of China (81673000)
Text and Data Mining valid from 2018-06-15
Received: 5 March 2018
Accepted: 14 May 2018
First Online: 15 June 2018
Ethics approval and consent to participate
: All of patients involved in this study consented to participate in the study and publication of its results. The study was approved and supervised by the Medical Ethic Committee of Peking University Cancer Hospital & Institute.
: The authors declare that they have no competing interests.
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