however , fetal free amino acid concentrations at 12 ( 18 ) were generally decreased ( alanine , 23.0 % ; valine , 9.7 % ; methionine , 22.6 % ; isoleucine , 12.0 % ; leucine , 18.2 % ) while uptake of the non-metabolizable amino acid , 14c-cycloleucine , was decreased 23 % .
C0002520
amino acid
C0001898
alanine