Imai, Naohiko http://orcid.org/0000-0001-9984-2889
Osako, Kiyomi
Kaneshiro, Nagayuki
Shibagaki, Yugo
Article History
Received: 5 June 2018
Accepted: 18 September 2018
First Online: 15 November 2018
Ethics approval and consent to participate
: Ethical approval for this study was obtained from ethical committee of St. Marianna University. The institutional review board at our facility approved this retrospective study and waived the need for written consent.
: Not Applicable.
: The authors declare that they have no competing interests.
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