Shimazui, Takashi
Nakada, Taka-aki
Tateishi, Yoshihisa
Oshima, Taku
Aizimu, Tuerxun
Oda, Shigeto
Article History
Received: 8 December 2017
Accepted: 25 February 2019
First Online: 1 March 2019
Ethics approval and consent to participate
: This study was approved by Chiba University Graduate School of Medicine Institutional Review Board and conducted with the Helsinki Declaration (approval number 2696). The need for written informed consent was waived because of the retrospective study design.
: Not applicable.
: The authors declare that they have no competing interests.
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