Zapała, Piotr
Dybowski, Bartosz
Poletajew, Sławomir
Białek, Łukasz
Niewczas, Andrzej
Radziszewski, Piotr
Article History
Received: 21 July 2017
Accepted: 8 January 2018
First Online: 15 January 2018
Ethics approval and consent to participate
: This retrospective study has been approved by the local review board. All procedures performed in studies involving human participants were in accordance with the 1964 Helsinki Declaration and its later amendments. Individual patient data are not reported within the study.
: Not applicable.
: The authors declare that they have no competing interests.
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