%0 Journal Article %T Trazabilidad de las mediciones realizadas con activ¨ªmetros en medicina nuclear %A Oropesa Verdecia %A Pilar %A Serra ¨¢guila %A Rolando A. %A Moreno Le¨®n %A Yecenia %A Hern¨¢ndez Rivero %A Aerulio T. %J Nucleus %D 2008 %I Scientific Electronic Library Online %X abstract in nuclear medicine, the administered doses of the radiopharmaceutical are expressed through the amount of radioactivity contained in the drug. the measurement of this activity, performed using a radionuclide calibrator, is of the utmost importance to guarantee the national and international comparability of clinic results and the radiological safety of the patient. in this paper, the transferring of the becquerel unit to the radionuclide calibrators employed in the nuclear medicine practice in cuba is detailed. the obtained results with an in situ calibration service, which is based on the direct comparison with standards of the specific measured radionuclides, are presented. outcomes of international and national measurement comparisons are shown. they validate the uncertainty estimates of the calibration coefficients installed in the instruments for measurements of , and , the main gamma emitters that have been used in cuban nuclear medicine. %K nuclear medicine %K calibration standards %K iodine 131 %K interlaboratory comparisons %K radiopharmaceuticals thallium 201 %K technetium 99. %U http://scielo.sld.cu/scielo.php?script=sci_abstract&pid=S0864-084X2008000200004&lng=en&nrm=iso&tlng=en