title: Systems of life. No 143. Senior systems. 8.
mesh_terms: D000368:Aged; D000375:Aging; D004386:Duodenum / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D010437:Peptic Ulcer / Q000503:physiopathology*; D013270:Stomach / Q000033:anatomy & histology / Q000502:physiology*