Influence of experience on intra- and interindividual variability in assessing peripheral endothelial dysfunction by measurement of flow associated vasodilation with high resolution ultrasound. - Balletshofer,B.M.; Goebbel,S.; Rittig Lehn-Stefan,K.A.; Renn,W.; Enderle,M.D.; Dietz,K.; Haering,H.U. (Ultraschall Med, 2001)