Funding for this research was provided by:
National Natural Science Foundation of China (81172532)
Text and Data Mining valid from 2018-09-14
Received: 20 May 2018
Accepted: 22 August 2018
First Online: 14 September 2018
Ethics approval and consent to participate
: This study was approved by the Tianjin Medical University Cancer Institute and Hospital, China, and has been performed in accordance with the ethical standards laid down in the 1964 Helsinki Declaration and its later amendments. Informed consent was obtained from all individual participants included in the study.
: Not applicable.
: The authors declare that they have no competing interest.
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