GastritisGastric MucosaGastritis, AtrophicHelicobacter pyloriHelicobacter InfectionsMetaplasiaPyloric AntrumStomach UlcerStomach NeoplasmsStomachChronic DiseasePeptic UlcerPepsinogen AGastroscopyStomach DiseasesAchlorhydriaGastric JuiceGastrinsDuodenal UlcerBiopsyDyspepsiaBile RefluxPepsinogen CDuodenitisGastritis, HypertrophicHelicobacterHelicobacter heilmanniiUreaseIntestinal MucosaHelicobacter felisPrecancerous ConditionsParietal Cells, GastricCampylobacterAtrophyEndoscopy, GastrointestinalAnti-Ulcer AgentsAntigens, BacterialPepsinogensBacterial ProteinsAmoxicillinGastric AcidLymphoma, B-Cell, Marginal ZoneOmeprazoleMouth MucosaAnemia, PerniciousAntibodies, BacterialCampylobacter InfectionsDuodenumH(+)-K(+)-Exchanging ATPaseLewis Blood-Group SystemImmunohistochemistryBipolar DisorderPolymerase Chain ReactionPostgastrectomy SyndromesClarithromycinGastric FundusGenotypeAdenocarcinomaMental DisordersCytotoxinsEndoscopyNasal MucosaAnxiety DisordersIntestinesMood DisordersGastric MucinsChoristomaDuodenogastric RefluxHyperplasiaCase-Control StudiesPrevalenceEndoscopy, Digestive SystemIntrinsic FactorImmunoglobulin GAutoimmune DiseasesMucous MembraneGastric Acidity DeterminationAcinonyxImmunoglobulin ARisk FactorsDNA, BacterialDiagnostic and Statistical Manual of Mental DisordersAnti-Bacterial AgentsEpithelial CellsSeverity of Illness IndexDrug Therapy, CombinationGastrointestinal DiseasesMexicoBismuthEnzyme-Linked Immunosorbent AssayMicroscopy, ElectronGastrin-Secreting CellsGerbillinaeGene Rearrangement, B-Lymphocyte, Heavy ChainPentagastrin