accelerometric tremorgrams were recorded from 25 subjects affected by essential tremor and analysed by a berg-fourier frequency analyser before and during venous infusion of the following drugs : propranolol ( beta-blocker ) , clonidine ( alpha-presynaptic adrenergic agonist ) , urapidil ( alpha-postsynaptic blocker ) , trazodone ( adrenolytic agent ) and placebo .
C0270736
essential
C0033497
propranolol