图271 小肠Small intestine
图272 十二指肠的构造Construction of the duodenum
图273 空肠（内面观）Jejunum (internal aspect)
图274 回肠（内面观）Ileum (internal aspect)
图275 空肠动脉弓Arterial arcades of the jejunal
图276 回肠动脉弓Arterial arcades of the ileum
