Funding for this research was provided by:
China Postdoctoral Science Foundation (2018M632260)
National Natural Science Foundation of Yangzhou City (YZ2017106, YZ2016128)
the Postdoctoral Science Foundation of Jiangsu Province (1701047C)
Text and Data Mining valid from 2019-04-09
Received: 12 December 2018
Accepted: 14 March 2019
First Online: 9 April 2019
Ethics approval and consent to participate
: Because of the retrospective nature of this study, informed consent was waived, and the study was approved by the Ethics Committee of our hospital.
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