Article History
Received: 19 September 2018
Accepted: 24 March 2019
First Online: 30 March 2019
Ethics approval and consent to participate
: Local ethics committee approval - Ethics committee of the Christian-Albrechts-University at Kiel, Chair: Prof. Dr. H.M. Mehdorn, study Ref. No. AZ 107/02, 26.04.2011. Written, informed consent of all patients.
: The authors declare that they have no competing interests.
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