among these it is to be assumed are the changes which condition the differences between plasma and serum under discussion . ( 16 ) even if these changes represent preliminary stages in coagulation ( liberation of the factors necessary to the formation of thrombin , for instance ) , they may still occur to a greater or less extent in blood which is prevented in certain ways from clotting since it is known that the procedures by which the various non-coagulable plasmas are obtained break at different points the chain of events which normally ends in coagulation .
C0229671
serum
C0032105
plasmas