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