PeristalsisEsophagusManometryDeglutitionGastrointestinal MotilityEsophageal Motility DisordersEsophageal Sphincter, LowerUreterPressureEsophageal AchalasiaEsophagogastric JunctionIleumMuscle ContractionMuscle, SmoothCineradiographyAirGuinea PigsRespiratory System AbnormalitiesKidney PelvisReflex, AbdominalIntestine, SmallDeglutition DisordersEnteric Nervous SystemUrinary Tract Physiological PhenomenaSenna ExtractGastroesophageal RefluxMethysergideScopolamine HydrobromideAtropineCatenanesEsophageal Sphincter, UpperPharynxDigestive System Physiological PhenomenaHernia, HiatalPurinergic AntagonistsFundoplicationSubmucous PlexusApaminEsophageal DiseasesReflexLaryngeal NervesBarium SulfateBornanesOpossums