tokens: The monoexponential rate of clearance of tracer - - obtained from the portion of the residue - detection curve reflecting metabolism of fatty acid incorporated into neutral lipids - - correlated directly with induced changes in tension - time index after injections into the left atrium ( r = 0 . 96 , n = 12 ) , right atrium ( r = 0 . 86 , n = 14 ) , and ear vein ( r = 0 . 93 , n = 14 ) .