GastritisHelicobacter pyloriHelicobacter InfectionsGastritis, AtrophicGastric MucosaHelicobacterMetaplasiaPyloric AntrumStomach NeoplasmsStomachChronic DiseasePeptic UlcerStomach UlcerPepsinogen AUreaseGastroscopyHelicobacter heilmanniiDyspepsiaAchlorhydriaStomach DiseasesDuodenitisPepsinogen CBiopsyGastrinsGastritis, HypertrophicDuodenal UlcerAntigens, BacterialBile RefluxAmoxicillinGastric JuiceAnti-Ulcer AgentsBacterial ProteinsClarithromycinEndoscopy, GastrointestinalOmeprazoleCampylobacterHelicobacter felisPrecancerous ConditionsHelicobacter hepaticusAtrophyAntibodies, BacterialLymphoma, B-Cell, Marginal ZoneMetronidazoleParietal Cells, GastricPolymerase Chain ReactionLewis Blood-Group SystemCytotoxinsCampylobacter InfectionsPepsinogensBismuthAnti-Bacterial AgentsAnemia, PerniciousDNA, BacterialGenotypeDrug Therapy, CombinationGastric Acid2-PyridinylmethylsulfinylbenzimidazolesDuodenumPostgastrectomy SyndromesImmunoglobulin GBreath TestsAcinonyxLansoprazoleEndoscopyImmunohistochemistryAdenocarcinomaProton Pump InhibitorsEndoscopy, Digestive SystemIntestinesGerbillinaePrevalenceAntacidsH(+)-K(+)-Exchanging ATPaseEnzyme-Linked Immunosorbent AssayImmunoglobulin AGastric Acidity DeterminationGastric FundusMolecular Sequence DataCase-Control StudiesRisk FactorsTinidazoleGastrointestinal DiseasesHyperplasiaMexicoDuodenogastric RefluxAutoimmune DiseasesGastroesophageal RefluxEsophagitisEpithelial CellsProspective StudiesSensitivity and SpecificityIntrinsic FactorRanitidine