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41.
H. K. Iversen T. H. Nielsen K. Garre P. Tfelt-Hansen J. Olesen 《European journal of clinical pharmacology》1992,42(1):31-35
Summary The aim of the present study was to compare the ability of different doses of isosorbide-5-mononitrate (5-ISMN) to cause dilatation of medium sized and small arteries, and to examine the intensity and duration of any headache produced. Ten healthy volunteers each received 3 doses of 5-ISMN and placebo on separate days. The diameters of the radial and superficial temporal arteries were repeatedly measured with high frequency ultrasound and pain was scored using a 10 point verbal scale.A clear dose-relationship was found for plasma concentrations and headache, and for changes in the diameter of the temporal artery, but not for the radial artery.It is concluded that headache after 5-ISMN is caused by arterial dilatation or by mechanisms responsible for the arterial dilatation. Ultrasound monitoring of arterial diameters is an important and sensitive tool in the evaluation of nitrates and other vasodilators. 相似文献
42.
Elie Mousseaux Iiana Idy-Peretti Jacques Bittoun Odile Jolivet Eric Bourroul Anne Tardivon Pierre Pronneau Jean-Claude Gaux 《Journal of magnetic resonance imaging : JMRI》1994,4(5):719-724
Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled. 相似文献
43.
How Cluster Headache is Explained as an Intracavernous Inflammatory Process Lesioning Sympathetic Fibers 总被引:2,自引:0,他引:2
SYNOPSIS
A large body of evidence points to an inflammatory process in the cavernous sinus and tributary veins as being primarily responsible for cluster headaches. The inflammation obliterates the venous outflow from the cavernous sinus on one side and injures the through-running sympathetic fibers to the eye, upper eye lid, forehead skin, and the intracranial internal carotid artery and its branches. The active period ends when the inflammation is suppressed and the sympathetic fibers partially or fully recover. Evidence is presented that the symptoms suggestive of an enhanced parasympathetic activity during attacks may alternatively be explained as local pain fiber activation or a stasis in the outflow from the cavernous sinus. Vasodilator agents like nitroglycerin induce an attack by enhancing the venous load on the cavernous sinus. Constriction of the proximal intracranial internal carotid artery, spontaneously induced by tressful pain activation of the perivascular sympathetic nerves, or by exogenous administration of serotonin 1 D-like receptor agonists or oxygen, terminates the venous load and thus the pain and associated symptoms. 相似文献
A large body of evidence points to an inflammatory process in the cavernous sinus and tributary veins as being primarily responsible for cluster headaches. The inflammation obliterates the venous outflow from the cavernous sinus on one side and injures the through-running sympathetic fibers to the eye, upper eye lid, forehead skin, and the intracranial internal carotid artery and its branches. The active period ends when the inflammation is suppressed and the sympathetic fibers partially or fully recover. Evidence is presented that the symptoms suggestive of an enhanced parasympathetic activity during attacks may alternatively be explained as local pain fiber activation or a stasis in the outflow from the cavernous sinus. Vasodilator agents like nitroglycerin induce an attack by enhancing the venous load on the cavernous sinus. Constriction of the proximal intracranial internal carotid artery, spontaneously induced by tressful pain activation of the perivascular sympathetic nerves, or by exogenous administration of serotonin 1 D-like receptor agonists or oxygen, terminates the venous load and thus the pain and associated symptoms. 相似文献
44.
通心络对颈动脉粥样硬化患者脑血流动力学的影响 总被引:7,自引:2,他引:5
目的 研究颈动脉粥样硬化伴脑供血不足患者 ,用通心络治疗前后血流动力学的变化。方法 给予 53例有颈动脉粥样硬化的脑供血不足的患者服用通心络胶囊 4粒 ,每日 3次 ,疗程为 4周。治疗前后采用经颅彩色多普勒 (transcranialdoppler,TCD)检测颅内各血管的血流变化 ,并与 30例老年健康体检者进行对照。结果 脑供血不足组各血管平均血流速度 (Vm)与健康对照组比较明显降低 (P <0 .0 5或 P <0 .0 1 ) ,且多数血管搏动指数 (PI)升高 (P <0 .0 5) ;治疗后脑供血不足组各血管的Vm较治疗前有显著性增高 (P <0 .0 5) ,且PI较治疗前有显著性降低 (P <0 .0 5)。结论 通心络可改善颈动脉粥样硬化患者的脑供血 ,是治疗和预防脑供血不足的有效药物 相似文献
45.
目的:探讨彩超检测高血脂患者颈动脉内膜-中膜厚度及斑块形成的意义,方法:medison-8000Ex高频超声对120例高血脂患者及120例血脂正常者两组,观察其动脉的内膜-中膜厚度及斑块形成情况。结果:血脂升高组,颈总动脉最大内膜-中膜厚度及粥样斑块发生率明显增高。结论:彩超可清晰显示颈动脉内膜-中膜情况,对高血脂引起的动脉粥样硬化检出预报和疗效观察有重要临床意义。 相似文献
46.
目的 了解二尖瓣环钙化(MAC)与颈动脉粥样硬化之间的关系,探讨MAC能否作为颈动脉粥样硬化的独立预测因子。方法 采用高频超声对156例MAC患者(其中55例为重度MAC患者)及118例年龄、性别与之相匹配的无MAC对照者的颈动脉进行了检测。结果 ①与对照组比较,MAC组及重度MAC组患者高血压和糖尿病的患病率明显增加(P〈0.05);②MAC组颈动脉粥样硬化斑块发生率,颈动脉狭窄≥20%、≥40%及双侧颈动脉狭窄≥40%的发生率均显著高于对照组(P〈0.01),重度MAC组上述指标的改变更为显著(P〈0.01)。此外,重度MAC组颈动脉狭窄≥60%的发生率明显高于对照组(P〈0.05);③MAC组及重度MAc组颈动脉内-中膜厚度(IMT)显著高于对照组(P〈0.01);④单因素及多因素Logistic回归分析结果均表明:MAC是颈动脉狭窄≥40%最有意义的预测因子(P〈0.01)。结论 MAC与颈动脉粥样硬化之间存在十分密切的关系,通过对MAC的检测,能够预测颈动脉粥样硬化的存在及其程度,在临床实际工作中,对于有二尖瓣环钙化的患者应常规进行颈动脉粥样硬化的检查。 相似文献
47.
目的 探讨冠心病患者与颈动脉粥样硬化之间的发生关系。方法 主要应用彩色多普勒超声技术检测 10 2例冠心病患者的颈动脉 ,对其中 34例进行冠状动脉造影检查。结果 为各组冠心病患者颈动脉管壁内 -中膜厚度 ,斑块指数均显著增高 ,其中心肌梗死患者伴有明显的血流参数异常 ,34例患者冠状动脉造影与颈动脉超声检查符合率为 75 % ,而且冠状动脉病变越重 ,颈动脉硬化发生率越高。结论 颈动脉粥样硬化程度可间接反映冠状动脉病变程度。 相似文献
48.
Petru Liuba Jerker Persson Jukka Luoma Seppo Yl?-Herttuala Erkki Pesonen 《European heart journal》2003,24(6):515-521
BACKGROUND: Atherosclerosis begins early in life. Infections might contribute to the pathogenesis of atherosclerosis. In this study, we investigated whether acute infections in children could alter the carotid wall morphology and the lipid profile. METHODS: Mean carotid intima-media thickness (IMT) was measured by high-resolution ultrasound in 28 hospitalised children (mean age: 5+/-2 years), who fulfilled the diagnostic criteria of acute infections (body temperature, >38 degrees C; C-reactive protein, >15mg/ml, and clinical), and in 20 age- and gender-matched controls. Antibodies against oxidised low-density lipoprotein (anti-oxLDL antibodies), as well as total and high-density lipoprotein cholesterol (HDL-C) were analysed in all children. The infection group was investigated both during the acute illness and 3 months after clinical recovery (post-infection). RESULTS: During the acute illness, the infection group had elevated anti-oxLDL antibodies and decreased HDL-C, as compared to those obtained at 3 months and in controls (p<0.05). These changes in the infection group were followed, at 3 months, by thickening of carotid intima-media. Those who received antibiotics during their acute illness had less carotid thickening than those who were not treated with antibiotics (p<0.05). CONCLUSION: Acute infections in children seem to be accompanied by enhanced oxidative modification of LDL and by decrease in HDL-C. These lipid changes may be followed by thickening of carotid artery intima-media. These findings suggest that, in childhood, acute infections could be associated with increased risk of atherosclerosis, and warrant further studies on this topic. 相似文献
49.
颈动脉分叉血液动力状态的计算流体力学初步研究 总被引:3,自引:2,他引:1
目的应用计算流体力学(CFD)方法结合血管影像显示在体颈动脉分叉的血流动力状态.方法选取1例志愿者,采用Siemens多层螺旋CT机行左侧颈动脉CT血管成像检查(CTA),扫描所得原始图像经计算机后处理后,用CFD方法计算并显示血液动力学各项指标.结果(1)该血管血液流率均值范围为0.04~0.36 m/s,颈外和颈内动脉的内侧壁(均以分叉顶点为参照)可见一高血流速区,球部可见较大片低血流速区;颈动脉分叉及颈内、外动脉近端均可见血液涡流与回流.(2)血液绝对压、静态压和动态压的均值范围分别为100 266.70~101 615.90 Pa、-10 58.34~290.88 Pa、6.12~553.25 Pa;(3)管壁切应力均值范围为0.59~5.35 Pa,在颈动脉球部及颈内动脉后壁显示大范围的低切应力区,最低约为0.25 Pa,颈外动脉前外侧壁存在一小范围低切应力区.结论CFD方法结合血管影像能计算并显示在体颈动脉分叉的个体化血液动力学指标. 相似文献
50.
Balloon occlusion of the internal carotid artery in 40 cases of giant intracavernous aneurysm: technical aspects,cerebral monitoring,and results 总被引:13,自引:2,他引:11
V. Vazquez Añon A. Aymard Y. P. Gobin A. Casasco D. Rüffenacht M. H. Khayata E. Abizanda A. Redondo J. J. Merland 《Neuroradiology》1992,34(3):245-251
Summary We have studied the results of carotid occlusion in the treatment of giant intracavernous carotid artery (ICA) aneurysms in 40 patients. Clinical, angiographic, Doppler and cerebral blood flow (CBF) criteria for tolerance of occlusion are discussed. The patients had headaches (47.5%), cranial nerve compression (87.5%), decreased visual acuity (20%), ruptured aneurysm (15%) and 5% were asymptomatic. Balloon occlusion tests were performed under light sedation anaesthesia: a successful test required perfect clinical tolerance and adequate angiographic collateral circulation in arterial, parenchymatous, and venous phases. Additional criteria include xenon 133 CBF measurements, and transcranial Doppler sonography of the middle cerebral artery. According to these criteria, 5 patients did not tolerate test occlusion and required an extra-intracranial (EC-IC) bypass. Mean follow-up was 4.7 years. All patients were radiologically cured of their ancurysm, and in 35 the symptoms resolved, although 3 had persistent ocular motor nerve palsies, and in 4 visual defects were unchanged. Complications were 1 permanent and 3 transient neurological deficits. Balloon occlusion of the ICA is an effective, reliable form of treatment for intracavernous giant aneurysm and should replace surgical ligation of the cervical carotid artery. With CBF or Doppler monitoring, the risk of neurological deficit is diminished. EC-IC bypass prior to ICA occlusion is indicated if test occlusion is not tolerated. 相似文献