[Determination of pH in the esophagus and gastric mucosa under direct observation using the endoscope].
D000818:Animals; D004285:Dogs; D004945:Esophagoscopy; D004947:Esophagus; D005753:Gastric Mucosa; D005773:Gastroscopy; D006863:Hydrogen-Ion Concentration; D008722:Methods; D009092:Mucous Membrane