1. 1 Military Medical Academy , Belgrade , Serbia , Department of gastroenterology ,
2. 2 Military Medical Academy , Belgrade , Serbia , Institute for Transfusiology and Haemobiology
3. 3 University of Kragujevac , Serbia , Faculty of Medical Sciences, Center for Molecular Medicine and Stem Cell Research
4. 4 University of Kragujevac , Serbia , Faculty of Medical Sciences, Department of Internal medicine
5. 5 University of Kragujevac , Serbia , Faculty of Medical Sciences, Department of Clinical pharmacy
6. 6 Military Medical Academy , Belgrade , Serbia , Department of Abdominal surgery
7. 7 University of East Sarajevo, BiH , Faculty of Medicine Foca, Department of Surgery
8. 8 University of Kragujevac , Serbia , Faculty of Medical Sciences, Department of Otorhinolaryngology