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Article History

Received: 15 September 2017

Accepted: 22 February 2018

First Online: 8 March 2018

Ethics approval and consent to participate

: The study was approved by the Tokyo Medical and Dental University Ethics committee (ref: D2014–047). We explained to people who participate in this research the study purposes and how to use date collected in this research. Written, informed consent was obtained from all participants before inclusion in the study.

: Informed consent to publish was obtained from the individuals shown in Fig. InternalRef removed.

: None of the authors have any competing interests in relation to this research paper.

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