title: Microbiological assay of vitamin B12 in liver extracts. Modification of the E. coli cup-plate method.
mesh_terms: D001681:Biological Assay / Q000379:methods; D004926:Escherichia coli / Q000187:drug effects; D008110:Liver Extracts / Q000032:analysis*; D014805:Vitamin B 12 / Q000032:analysis*
chemical_list: D008110:Liver Extracts; D014805:Vitamin B 12