Hydrochloric AcidPneumonia, AspirationNitric AcidGastric JuiceDecalcification TechniqueTrifluoroacetic AcidCountercurrent DistributionEsophagusHydrogen-Ion ConcentrationAcidsStomachFluoroacetatesAchlorhydriaParietal Cells, GastricSulfuric AcidsGastric AcidGastric FistulaGastric MucosaSodium HydroxideAlkalosisPentagastrinPepsin AAppendixAcidosisDuodenumSodium ChlorideSpectrophotometry, AtomicSecretinStomach UlcerBicarbonatesHydrolysis