title: Vitamin B12 in human blood and serum. I. Comparison of microbiologic assays using normal subjects.
mesh_terms: D001681:Biological Assay; D006397:Hematinics; D006801:Humans; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D006397:Hematinics; D014805:Vitamin B 12
keywords: BIOLOGICAL ASSAY; VITAMIN B 12/blood