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91.
报告1例鼻咽癌颈淋巴结转移致颈动脉窦过敏综合征和1例全喉切除加颈淋巴结清扫术术后瘢痕形成出现颈动脉窦过敏综合征。对耳鼻咽喉科相关疾病引起的颈部肿块和瘢痕病变压迫颈动脉窦所致颈动脉窦过敏综合征的致病原因、临床表现及诊断、治疗原则进行了讨论。此类患者在临床上少见,易误诊,应引起重视。 相似文献
92.
The inhibitory effect of nitric oxide (NO) on carotid chemosensory responses to hypoxia has been attributed in part to an antidromic inhibition of chemoreceptor cells activity. However, NO may also modulate the activity of the primary sensory neurons because NO is produced in the soma of these neurons located in the petrosal ganglion. Since a population of petrosal neurons is selectively activated by acetylcholine (ACh), we studied the effects of NO-donor, sodium nitroprusside (SNP), and the NO-synthase inhibitor, Nomega-nitro-l-arginine methyl ester (l-NAME), on the responses evoked in the carotid sinus nerve (CSN) by ACh applied to the petrosal ganglion in vitro. ACh (1 microgram-1 mg) increased the frequency of action potentials recorded from the CSN in a dose-dependent manner. SNP (10-50 microM) reduced the sensibility and amplitude of the CSN response to ACh, although the maximal response appears less affected. The withdrawal of SNP from the superfusion medium increased the sensibility of the responses to ACh. l-NAME (1-2 mM) slightly increased the sensibility of the ACh-induced responses, effect that persisted after l-NAME withdrawal. These results suggest that NO may play a role as modulator in this autonomic primary sensory ganglion. 相似文献
93.
目的:研究NOS、O2-·和Ca2+在犬高动力型肺动脉高压形成中的意义,控讨O2-·、[Ca2+]i在L一精氨酸→NO通路上的调节作用。方法:6只高动力型肺动脉高压模型犬,检测肺组织NOS活性,丙二醛(MDA)含量及总钙含量。结果:与正常比较,肺高压时,肺组织NOS活性较正常明显降低(P<0.01),MDA、[Ca2+]i;含量明显升高(P<0.05),肺组织NOS与平均肺动脉压(MPAP)、肺血管阻力(PVR)、[Ca2+]i及MDA呈明显负相关。结论:NO作用减弱在肺高压形成中与限速酶NOS活性降低密切相关,O2·和[Ca2+];共同介导肺高压过程。 相似文献
94.
Solaro M. Roberti C. Spalloni A. Mancini G. Beccia M. Rasura M. 《The Italian Journal of Neurological Sciences》1996,17(1):75-78
Over the last few years, many authors have described the possibility of using transcranial Doppler to demonstrate the passage of microemboli in the cerebral arteries. We report the case of a 44-year-old woman with thrombotic diathesis and thrombocytosis who was admitted twice within a short period of time (one and a half months) to a neurological department because of multiple cerebral infarctions. On the occasion of the second admission, a colour-Doppler examination of the epiaortic vessels, which had previously been negative, showed a carotid lesion due to a mural thrombus and, on the same side as the carotid lesion, transcranial Doppler detected short-duration, high-intensity signals in the middle and anterior cerebral arteries, an expression of the passage of microemboli.As already described by other authors in similar clinical situations, our case confirms that transcranial Doppler can identify the passage of microemboli in the circle of Willis.
Sommario Negli ultimi anni è stata descritta da molti autori la possibilità di dimostrare mediante Doppler transcranico il passaggio di microemboli nelle arterie cerebrali. Riportiamo il caso di una donna di 44 anni con diatesi trombotica e trombocitosi ricoverata per due volte, a breve distanza di tempo (un mese e mezzo), in ambiente neurologico per infarti cerebrali multipli. In occasione del secondo ricovero l'esame Color-Doppler dei vasi epiaortici, che era risultato negativo in precedenza, ha evidenziato una lesione carotidea riferibile a un trombo murale e al Doppler transcranico sono stati rilevati, omolateralmente alla lesione carotidea, segnali di breve durata ed alta intensità nelle arterie cerebrali media e anteriore, espressione di passaggio di microemboli.Come già descritto da alcuni autori in situazioni cliniche simili, il nostro caso conferma la possibilità di individuare, mediante Doppler transcranico, il passaggio di microemboli nel circolo cerebrale.相似文献
95.
Summary A patient with migraine headaches of the cluster variant type is presented in whom vasospasm of the middle cerebral artery, the anterior cerebral artery and the internal carotid artery triggered a pain episode identical in character and severity to the headaches which had led to her investigation. Vasospasm associated with the painful phase of headache in this case conflicts with the more accepted theory that the pain phase of a vascular headache is related to vasodilatation of cerebral or extracerebral vessels. The literature is reviewed. 相似文献
96.
A. Klausmair N. Singewald A. Philippu 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):155-160
Summary The effects of carotid occlusion on the release of catecholamines in the nucleus of the solitary tract (NTS) were investigated in anaesthetized cats. Two aspects of the nucleus (rostral or intermediate NTS) were superfused bilaterally through push-pull cannulae with artificial CSF and the release of the endogenous dopamine, noradrenaline and adrenaline was determined in the superfusate radioenzymatically. The superfusion rate was 150 l/min or 800 l/min. In some experiments, superfusion of the intermediate NTS was carried out after denervation of the aortic arch.In the rostral NTS superfused at a rate of 150 l/min, bilateral carotid occlusion led to a rise in blood pressure and decreased the release rate of dopamine. These changes continued after occlusion termination. The release rate of noradrenaline was transiently diminished during occlusion. The release of this amine was also decreased after occlusion termination. The release rate of adrenaline was not influenced during carotid occlusion, but it was found to be diminished after termination of the occlusion. Superfusion of the rostral NTS at a rate of 800 l/min also reduced the release rate of adrenaline after termination of carotid artery occlusion. In the intermediate NTS (superfusion rate 150 l/min) similar effects of the carotid occlusion on the release rates of dopamine and noradrenaline were observed. In this aspect of the NTS, denervation of the aortic arch abolished the decrease in the noradrenaline release during carotic occlusion, while the release rates of dopamine and adrenaline were decreased during and after termination of the carotid occlusion.The results suggest that (a) the rise in blood pressure in the carotid sinus after termination of a carotid occlusion decreases the release rates of noradrenaline and adrenaline in the NTS, (b) the decrease in the release of noradrenaline during carotid occlusion is due to impulses originating from the baroreceptors of the aortic arch.Thus, impulses from carotid sinus and aortic arch modify the release rates of noradrenaline in the NTS so as to counteract blood pressure changes.Supported by the Fonds zur Förderung der wissenschaftlichen Forschung
Send offprint requests to A. Philippu at the above address 相似文献
97.
We report here a 54-year-old man with an aneurysm arising on a cervical anterior radiculomedullary artery. The aneurysm ruptured
just after vertebral angiography for a vascular anomaly of the brain, and it appeared to be fusiform, with thrombosis following
angiography. Considering the sequential radiological studies and clinical course, it was assumed to be a dissecting aneurysm
caused by the angiography. MRI showed severe swelling of the cervical spinal cord and an infarct in the territory of the anterior
spinal artery. The mechanism of this rare complication is discussed.
Received: 29 March 1999 Accepted: 18 August 1999 相似文献
98.
99.
LDL-C/HDL-C比值及颈动脉粥样硬化性狭窄与脑梗塞发病关系的探讨 总被引:5,自引:0,他引:5
目的 研究低密度脂蛋白胆固醇(LDL-C)/高密度脂蛋白胆固醇(HDL-C)比值以及颈动脉粥样硬化性狭窄与脑梗塞发病的关系,并探讨其预测脑梗塞发生的价值。方法 应用彩色多普勒显保仪对非脑梗塞组患者328例(高血压198例、糖尿病82例、高血压伴糖尿病48例)和脑梗塞组患者260例进行颈动脉检测,观察颈动脉狭窄程度;同时检测两组患者的LDL-C/HDL-C比值水平。结果 脑梗塞组颈动脉重度狭窄发生率明显高于非脑梗塞组(P<0.01);LDL-C/HDL-C比值水平及异常率也明显高于非脑梗塞组(P<0.01),相关分析显示与甘油三酯(TG)、总胆固醇(Tch)、LDL和HDL-C相比,该比值显示了更有意义的与脑梗塞的相关关系(β=0.357,P=0.001),经多元逐步回归分析显示,与TG、Tch、LDL-C和HDL-C相比,该比值显示了更有意义的回归关系,其标准方程式为:γ(脑梗塞)=0.339(糖尿病史) 0.278(LDL-C) 0.187(高血压史)(P<0.贴,复相关系数为0.534)。结论 应用颈动脉超声判定颈动脉重度狭窄和检测LDL-C/HDL-C比值水平及异常率对预测脑梗塞的发生有一定的实用参考价值。 相似文献
100.
目的 探讨颈总动脉切除术的适应症和术前准备的一般规律。方法 对我院自1986年~2003年17年问的10例颈总动脉切除术病例进行回顾性分析。其中年龄22~59岁,急诊手术4例,选择性颈动脉切除6例。结果 急诊手术中2例出现中枢神经系统并发症,选择性手术组中1例出现中枢神经系统并发症。除1例因脑转移癌死亡外,随访均健在。结论 行不重建血管的颈总动脉及分歧部切除术,高龄患者须严格掌握适应症,须无脑血管疾病史,术前须进行Matas试验,要有侧支循环建立的客观依据;对年轻患者(30岁以下)可适当放宽手术指征。 相似文献