Iijima, Shigeo http://orcid.org/0000-0003-3391-3757
Article History
Received: 12 February 2017
Accepted: 7 February 2018
First Online: 14 February 2018
Ethics approval and consent to participate
: This study conformed with the concepts of the Declaration of Helsinki and was reviewed and approved by the ethics committee on human research of the Toho University Medical Center (reference 22,014). Written parental consent was obtained for each study participant through a signed consent form.
: Not applicable.
: The authors declare that they have no competing interests.
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