the usefulness of endoscopic examination of patients subjected to vagotomy and drainage for duodenal ulcer is stressed , since it permits recurrences and ineffective treatment to be detected , along with the control of other parameters , such as the appearance of the mucosa , the performance of gastric drainage , the features of peristalsis and gastric tone , and the performance of the cardial sphincter .
C0038351
gastric
C0007144
cardial