Krysiak, Robert
Szwajkosz, Anna
Okopień, Bogusław
Article History
Received: 23 October 2017
Revised: 5 March 2018
Accepted: 29 April 2018
First Online: 5 July 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: The study was approved by the Bioethical Committee of the Medical University of Silesia.