GastritisGastritis, AtrophicBacteriaHelicobacter pyloriGastric MucosaHelicobacter InfectionsPyloric AntrumGram-Negative BacteriaGastritis, HypertrophicGram-Positive BacteriaMetaplasiaStomachGastroscopyPepsinogen ABacteria, AnaerobicStomach NeoplasmsBacterial ProteinsAchlorhydriaRNA, Ribosomal, 16SBile RefluxDNA, BacterialStomach UlcerMolecular Sequence DataGastrinsBacteria, AerobicPeptic UlcerPepsinogen CPhylogenyStomach DiseasesDuodenal UlcerHelicobacter felisHelicobacter heilmanniiChronic DiseaseDNA, RibosomalParietal Cells, GastricDuodenitisHelicobacterAnemia, PerniciousEscherichia coliUreaseSequence Analysis, DNAAnti-Bacterial AgentsDyspepsiaBiopsyGastric JuiceWater MicrobiologyGram-Negative Anaerobic BacteriaPepsinogensPostgastrectomy SyndromesColony Count, MicrobialAntigens, BacterialCampylobacterGram-Negative Aerobic BacteriaGenes, BacterialBacterial Physiological PhenomenaPrecancerous ConditionsSoil MicrobiologyEndoscopy, GastrointestinalAntibodies, BacterialGene Expression Regulation, BacterialSulfur-Reducing BacteriaRNA, BacterialSeawaterGenome, BacterialAcinonyxAtrophyBacterial AdhesionPolymerase Chain ReactionEndoscopyCulture MediaAnti-Ulcer AgentsAmoxicillinBase SequenceGastric AcidSpecies SpecificityAnaerobiosisGenes, rRNASymbiosisAmino Acid SequenceH(+)-K(+)-Exchanging ATPaseBase CompositionAutoimmune DiseasesOmeprazoleBiodegradation, EnvironmentalIntestinesDuodenogastric RefluxGastric FundusPseudomonasVirulenceEnterobacteriaceaeEndoscopy, Digestive SystemGastroenterostomyBacterial Typing TechniquesBacterial InfectionsHydrogen-Ion ConcentrationIntrinsic FactorBismuthMicrobial Sensitivity TestsCampylobacter InfectionsFresh Water