Hirai, Toshinori http://orcid.org/0000-0002-3898-2068
Ogawa, Ryuichi
Yamaga, Ryosuke
Itoh, Toshimasa
Article History
Received: 6 August 2018
Accepted: 7 November 2018
First Online: 3 December 2018
Ethics approval and consent to participate
: The study protocol was approved by the institutional review board at Tokyo Women’s Medical University Hospital (#4467).
: Not applicable.
: The authors declare that they have no competing interests.
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