Analysis of the prevalence of Helicobacter pylori infection and the effectiveness of eradication schemes in patients with the upper gastrointestinal tract disorders (according to the results of 13C-urea breath tests for 2006–2019) - Kondratiuk, Nataliia; Paliy, Iryna; Zaika, Serhii (Gastroenterology Review/Przegląd Gastroenterologiczny, 2021)