1. School of Medicine, Belgrade + Clinical Center of Serbia, Clinic of Nephrology, Belgrade
2. School of Medicine, Belgrade + Clinical-Hospital Center “Dr Dragiša Mišović”, Department of Dialysis, Belgrade
3. University of Belgrade, School of Medicine, Belgrade + Clinical Center of Serbia, Clinic for Digestive Diseases, Belgrade
4. School of Medicine, Institute of Medical Physiology, Belgrade
5. School of Medicine, Institute of Pathophysiology, Belgrade