serum samples that gave diagnostically discrepant results when their vitamin b12 content was analysed ( i ) by a commercial radioassay known to be susceptible to interference from cobalamin analogues , and ( ii ) by microbiological assay , were further analysed by an alternative radioassay which uses the transcobalamins ( principally tc ii ) of diluted normal serum as the assay binding protein .
C0042845
vitamin b12
C2917443
cobalamin analogues