1. Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Dr Subotica 1, 11129 Belgrade, Serbia
2. Faculty of Medicine, University of Belgrade, Dr Subotica 1, P.O. Box 38, 11129 Belgrade, Serbia
3. Department of Pathology, School of Dental Medicine, University of Belgrade, Dr Subotica-Starijeg 1, 11000 Belgrade, Serbia
4. Institute for Medical Statistics and Informatics, Faculty of Medicine, University of Belgrade, 11129 Belgrade, Serbia
5. Clinic for Otorhinolaryngology and Maxillofacial Surgery, University Clinical Center of Serbia, Pasterova 2, 11000 Belgrade, Serbia