A bacterium was identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。The ulcer perforated the duodenal wall.溃疡造成了十二指肠壁穿孔。Reflux of duodenal content into the stomach may be a factor in the development of gastric neoplasia.十二指肠内容物回流可能是胃部肿瘤形成的原因之一。