'One kind of this is a wound on the skin; another kind affects the mucous membrane as in the lower esophagus'
an ulcer
YOUR BODY AND U: One kind of this is a wound on the skin; another kind affects the mucous membrane as in the lower esophagus
One kind of this is a wound on the skin; another kind affects the mucous membrane as in the lower esophagus
One kind of this is a wound on the skin; another kind affects the mucous membrane as in the lower esophagus
YOUR BODY AND "U"
an ulcer
YOUR BODY AND "U"