Definition: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
Input: Abstract: The effects of cimetidine on the healing and recurrence of duodenal ulcers and gastric ulcers were compared. The extent of the acid secreting areas was examined by the endoscopic Congo red methylene blue test. Using the extent of acid secreting areas gastric ulcers were classified into ulcers with and without extensive acid secreting areas. Duodenal ulcers were all associated with extensive acid secreting areas. The gastric acid outputs in the basal state and after maximal stimulation with gastrin were highest in duodenal ulcers, and lowest in gastric ulcers without extensive acid secreting areas. Cimetidine treatment significantly promoted the healing of duodenal ulcers and gastric ulcers with extensive acid secreting areas when compared with placebo, but not of the gastric ulcers without extensive acid secreting areas. Cimetidine also significantly diminished the recurrence of duodenal ulcers, but not gastric ulcers with and without extensive acid secreting areas. These findings indicate that in Japan cimetidine promotes the healing of duodenal and gastric ulcers associated with high gastric acid production and prevents recurrence of duodenal ulcers, but has little or no influence on the healing and recurrence of gastric ulcers associated with low acid secretion.

Double-Blind Method