Effects of vasodilating drugs on the lower esophageal sphincter pressure of patients with megaesophagus - Dantas, Roberto Oliveira; Godoy, Renato Alves de; Rezende Filho, J; Oliveira, B R; Villanova, M G; Meneghelli, U G; Troncon, L E A (Brazilian Journal of Medical and Biological Research, 1985)