Ileum: Final and longest segment of the small intestine.It is the site of absorption of vitamin B12 (see vitamin B complex ) and reabsorption of about 90% of conjugated Bile salts.

• 回肠:小肠最后和最长的一段,主要担负维生素B12的吸收和结合胆汁盐约90%25的重吸收。