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Article History

Received: 7 January 2020

Accepted: 20 July 2020

First Online: 29 July 2020

Ethics approval and consent to participate

: Not applicable. Since this study was a retrospective investigation, the Ethics Committee of Tongji Medical College, Huazhong University of Science and Technology ruled that no formal ethics approval was required. Written consents to participate in this study were obtained from the legal guardians of every patient.

: Written consents were obtained from the legal guardians of every patient in this study for publication of this paper.

: The authors declare that they have no competing interests.