Korsun, Neli
Angelova, Svetla
Trifonova, Ivelina
Georgieva, Irina
Voleva, Silvia
Tzotcheva, Iren
Mileva, Sirma
Ivanov, Ivan
Tcherveniakova, Tatiana
Perenovska, Penka
Article History
Received: 17 May 2018
Accepted: 1 October 2018
First Online: 5 December 2018
Compliance with ethical standards
: This study was carried out in accordance with <i>The Code of Ethics of the World Medical Association</i> (Declaration of Helsinki) for experiments involving humans ExternalRef removed.
: The authors declare that they have no conflicts of interest relevant.
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