The sample size calculation was based on the following assumptions: in previous studies from our own group, we found that the vasodilator response to the intrabrachial administration of adenosine averages 2.8±0.6, 4.4±1.0, 9.0±1.7 ml/min per dl of forearm volume for 0.5, 1.5, and 5.0 μg/min/dl, respectively (mean±SEM, n = 8).
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