■ Erosion糜烂: a superficial lesion caused by denudation of the surface epithelium 上皮细胞) ■lcer溃: a mucosal defect extending into the muscularis mucosa(粘膜肌层)Erosion糜烂 : a superficial lesion caused by denudation of the surface epithelium （上皮细胞） ulcer 溃疡: a mucosal defect extending into the muscularis mucosa(粘膜肌层)