GastritisGefarnateMetaplasiaStomach UlcerGastritis, AtrophicGastrointestinal HemorrhageHelicobacter pyloriGastric MucosaHelicobacter InfectionsPyloric AntrumGastritis, HypertrophicStomachGastroscopyPepsinogen AStomach NeoplasmsAchlorhydriaBile RefluxGastrinsPeptic UlcerPepsinogen CStomach DiseasesDuodenal UlcerHelicobacter felisHelicobacter heilmanniiParietal Cells, GastricChronic DiseaseDuodenitisAnemia, PerniciousDyspepsiaHelicobacterBiopsyUreasePepsinogensPostgastrectomy SyndromesGastric JuicePrecancerous ConditionsEndoscopy, Gastrointestinal