Popov, V.
Yonkov, A.
Arabadzhieva, E. http://orcid.org/0000-0001-6638-4156
Zhivkov, E.
Bonev, S.
Bulanov, D.
Tasev, V.
Korukov, G.
Simonova, L.
Kandilarov, N.
Taseva, A.
Dimitrova, V.
Article History
Received: 2 November 2017
Accepted: 2 January 2019
First Online: 10 January 2019
Ethics approval and consent to participate
: Written informed consent was obtained from the patients for the performance of the specific procedure, participation in the study and publication of the results and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.All procedures performed in the study were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.Trial registration: researchregistry3090.
: Not applicable
: The authors declare that they have no competing interests.
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