Text and Data Mining valid from 2018-11-24
Received: 3 October 2018
Accepted: 15 November 2018
First Online: 24 November 2018
Ethics approval and consent to participate
: The study protocol was approved by our institution’s ethics committee, and informed consent for the procedure was obtained from each individual.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.