Article History
Received: 14 November 2017
Accepted: 5 April 2018
First Online: 31 May 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board and Clinical Ethics Committee of Shanghai General Hospital, Shanghai Jiaotong University School of Medicine. The written informed consent from either the patients or their representatives was waived due to the retrospective nature of this study in accordance with the American Medical Association.
: The authors declare that they have no competing interests.
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