1. Department of Nursing and Obstetrics, Division of Anesthesiological and Surgical Nursing, Faculty of Health Science, Wroclaw Medical University, 50-367 Wroclaw, Poland
2. Department of Surgery, 4th Military Teaching Hospital, 50-981 Wroclaw, Poland
3. Student Research Club No 180, Faculty of Medicine, Wroclaw Medical University, 50-367 Wroclaw, Poland
4. Department of Clinical and Experimental Pathology, Faculty of Medicine, Wroclaw Medical University, 50-367 Wroclaw, Poland
5. Department of Pathomorphology, 4th Military Teaching Hospital, 50-981 Wroclaw, Poland