title: Endoscopic appearance of the lower esophageal sphincter in achalasia: a diagnostic sign.
authors.forename: M L
authors.initials: ML
authors.lastname: Levine
mesh_terms: D000368:Aged; D004931:Esophageal Achalasia / Q000473:pathology*; D004943:Esophagogastric Junction / Q000473:pathology*; D004945:Esophagoscopy; D006801:Humans; D008297:Male