Text and Data Mining valid from 2018-07-21
Received: 22 February 2018
Accepted: 9 July 2018
First Online: 21 July 2018
Ethics approval and consent to participate
: The study was approved by the institutional review board of the Technical University of Munich (No. 353/ 15) and conducted according to the Declaration of Helsinki. All patients gave their written informed consent to participate in this investigation.
: Not applicable.
: The authors declare that they have no competing interests.
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