this transcranial pulsed doppler ( t.p.d . ) test was used to study the effect of a calcium inhibitor , nifedipine , on middle cerebral artery smooth muscle and its cerebrovascular effects in 28 subjects : 8 cases of hypertension , 9 of sylvian artery stenosis confirmed by arteriography ( 5 approximately equal to 30 % and 4 greater than or equal to 50 % ) and 11 healthy volunteers .
C0028066
nifedipine
C0020538
hypertension