Chanarin I, England J M, Rowe K L, Stacey J A
Br Med J. 1972 May 20;2(5811):441-2. doi: 10.1136/bmj.2.5811.441.
A third vitamin B(12) binding protein present in normal serum has been shown to participate in transport of labelled vitamin B(12) absorbed from the gut. All three vitamin B(12) binding proteins in serum were labelled at the same time after oral administration of vitamin B(12), implying that "free" vitamin B(12) reached the portal blood from the gut mucosa.
正常血清中存在的第三种维生素B12结合蛋白已被证明参与从肠道吸收的标记维生素B12的转运。口服维生素B12后,血清中的所有三种维生素B12结合蛋白同时被标记,这意味着“游离”维生素B12从肠黏膜到达门静脉血。