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Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.  相似文献   
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The authors report of practical experience with a radioprotective shield. This kind of radiohygiene is recommended for routine stomatological radiodiagnosis by the State Board of Nuclear Safety and Radiological Protection of the GDR.  相似文献   
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Corresponding to the different objectives, the Working Group on Radiology of the Stomatological Society has designed 6 standardized work places for routine radiodiagnosis in stomatology. Apart from the objectives, the problems related to the division of rooms, equipment, radioprotection and film processing are dealt with separately and specifically. The work places for routine stomatological radiodiagnosis are intended for achieving an improvement in a sector of stomatological care.  相似文献   
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BACKGROUND AND PURPOSE: The aim of this study was to assess the role of spiral CT for the diagnosis of brain death. METHODS: Over a 12-month period, 15 patients that fulfilled the clinical criteria of brain death were referred from the intensive care unit to evaluate remaining intracranial blood flow by spiral CT. The clinical diagnosis was confirmed by an apnea test in all cases. Two phases of spiral CT were performed at 20 and 60 seconds after the start of contrast media injection. Qualitative analysis included the evaluation of vessel opacification (arteries and veins) by two radiologists in consensus. RESULTS: The cortical segments of the middle cerebral artery (MCA) were assessable in all patients, whereas the internal cerebral veins could not be evaluated in five patients due to artifacts or intracranial hemorrhage. Opacification of the major branches of the circle of Willis was observed in seven cases. Unilateral opacification of cortical branches of the MCA occurred in one. We did not observe bilateral enhancement of cortical MCA branches. The internal cerebral veins did not enhance in brain death. CONCLUSION: The absence of internal cerebral vein opacification and the absence of bilateral enhancement of cortical MCA branches constituted the best criteria of brain death by contrast enhanced spiral CT.  相似文献   
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