by conventional anti-cea antisera , nca-2 in meconium , nfa-2 in adult feces , and cea in tumor tissues were indistinguishable from each other , but they could be distinguished by specific antibody preparations against a determinant unique to cea ( cea-distinctive determinant ) or to nfa-2 ( nfa-2-distinctive determinant ) .
C0003320
nfa-2
C0003316
nfa-2