title: 24-hour pH monitoring in the study of gastroesophageal reflux.
mesh_terms: D004942:Esophagitis, Peptic / Q000175:diagnosis / Q000503:physiopathology; D005744:Gastric Acid / Q000378:metabolism; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008991:Monitoring, Physiologic; D011187:Posture; D013997:Time Factors