Higashihori, Norihisa
Takada, Jun-ichi
Katayanagi, Minami
Takahashi, Yuki
Moriyama, Keiji
Article History
Received: 9 April 2018
Accepted: 5 June 2018
First Online: 20 August 2018
Ethics approval and consent to participate
: All procedures in this study were approved by the Ethics Committee of Tokyo Medical and Dental University (No. 419) and complied with the Code of Ethics of the World Medical Association (Declaration of Helsinki).
: Not applicable
: The authors declare that they have no competing interests.
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