1 Department of Anatomy and Cell Biology, Faculty of Medicine, Medical University - Varna "Prof. Dr. Paraskev Stoyanov", Varna, Bulgaria. georgi.geesh@gmail.com.
2 Department of Physiology and Pathophysiology, Faculty of Medicine, Medical University - Varna "Prof. Dr. Paraskev Stoyanov", Varna, Bulgaria. georgi.geesh@gmail.com.
3 Department of General and Clinical Pathology, Forensic Medicine and Deontology, Faculty of Medicine, Medical University - Varna "Prof. Dr. Paraskev Stoyanov", Varna, Bulgaria.