Text and Data Mining valid from 2018-08-23
Received: 11 February 2018
Accepted: 15 August 2018
First Online: 23 August 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of the Chinese PLA General Hospital, and because of the retrospective nature of the study the requirement of informed consent was waived. All patients provided informed consent for the surgical procedures performed.
: Not Applicable.
: Dr. HTX, Dr. TY, Dr. YL, Dr. BL, Dr. JW and Dr. JHD have no conflicts of interest or financial ties to disclose. The authors declare that they have no competing interests.
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