Funding for this research was provided by:
Uniwersytet Medyczny w Bialymstoku (N/ST/ZB/15/001/1143 and N/ST/ZB/15/003/1143)
Received: 16 July 2018
Accepted: 28 August 2018
First Online: 12 September 2018
Ethics approval and consent to participate
: The protocol was approved by the Bioethics Committee of the Medical University of Bialystok in accordance with the Declaration of Helsinki.
: Not applicable
: The authors declare that they have no competing interests.
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