Assertion: lewis antigen | /r/HasProperty | expressed
Facets:
value: weakly
type: DEGREE
value: during pregnancy
type: TEMPORAL
Source sentences:
text: Lewis antibodies in a pregnant woman are essentially totally insignificant because they are IgM subtype (don't cross the placenta) and Lewis antigen is weakly expressed during pregnancy (Lewis Le(a-b-) phenotype is commonly seen during gestation).