Article History
Received: 5 December 2017
Accepted: 30 October 2018
First Online: 13 November 2018
Authors’ information
: Not applicable.
: All procedures performed in this study were in accordance with the Declaration of Helsinki and approved by the Ethics Committee of the First Affiliated Hospital of Guangxi Medical University (Reference Number: KY-E-062). Because of the retrospective nature of the research, the requirement for informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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