regional and non-regional ( rln , nrln ) lymph nodes , were subjected to stereological analysis to determine the volume fractions ( vv ) of the cortex ( c ) , the paracortex ( pca ) , the germinal centers ( gc ) , and the medulla ( m ) , using a computerized analysis system ( ibas i , kontron ) .
C0024204
lymph nodes
C0282491
germinal centers