Text and Data Mining valid from 2018-04-06
Received: 8 November 2017
Accepted: 28 March 2018
First Online: 6 April 2018
Ethics approval and consent to participate
: The study was approved by the ethics committee of the University Hospital Essen prior to patient recruitment. All patient gave oral and written informed consent before being included.
: Not applicable.
: The authors declare that they have no competing interests.
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