Text and Data Mining valid from 2018-04-03
Received: 4 September 2017
Accepted: 21 March 2018
First Online: 3 April 2018
Ethics approval and consent to participate
: This research conformed to the provisions of the Declaration of Helsinki. All patients were informed of the investigational nature of this study and provided their written informed consent. This retrospective study was approved by the ethics committee of Osaka City University (approval No.3853).
: Not applicable.
: The authors declare that they have no competing interests.
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