Text and Data Mining valid from 2018-05-10
Received: 13 January 2018
Accepted: 1 May 2018
First Online: 10 May 2018
Ethics approval and consent to participate
: This study was performed in accordance with the ethics committee requirements of Osaka University and with the Declaration of Helsinki.
: Written consent for publication was obtained from the patient’s next of kin. A copy of the consent form is available for review by the editor of this journal.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.