Investigating the oesophagus.
D001466:Barium Sulfate; D004935:Esophageal Diseases / Q000175:diagnosis*; D004945:Esophagoscopy; D004947:Esophagus / Q000000981:diagnostic imaging; D005764:Gastroesophageal Reflux / Q000175:diagnosis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011312:Pressure; D011859:Radiography
D001466:Barium Sulfate