Ma, Zhaoxin
Huang, Shilei
Sun, Jianguang
Li, Feng
Sun, Jianhao
Pi, Guofu http://orcid.org/0000-0001-9176-5436
Article History
Received: 5 December 2018
Accepted: 11 March 2019
First Online: 28 March 2019
Authors’ information
: Not applicable.
: This retrospective study was approved by the Institutional Ethics Board of The First Affiliated Hospital of Zhengzhou University. All enrolled patients were informed and agreed to provide relevant data for this study. The methods were carried out in accordance with the relevant guidelines.
: Not applicable.
: The authors declare that they have no competing interests.
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