Text and Data Mining valid from 2018-09-17
Received: 22 May 2018
Accepted: 4 September 2018
First Online: 17 September 2018
Ethics approval and consent to participate
: The present study was approved by the ethics committee of the Würzburg University Hospital (approval number: 42/13).
: Not applicable.
: The authors declare that they have no competing interests.
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