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61.
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   
62.
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   
63.
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   
64.
Antibodies to the lysosomal hydrolases, cathepsins B and D and β-hexosaminidase A, revealed alterations of the endosomal-lysosomal system in neurons of the Alzheimer disease brain, which preceded evident degenerative changes and became marked as atrophy, neurofibrillary pathology, or chromatolysis developed. At the earliest stages of cell atrophy, hydrolase-positive lysosomas accumulated at the basal pole and then massively throughout the perikarya and proximal dendrites of affected pyramidal neurons in Alzheimer prefrontal cortex and hippocampus, far exceeding the changes of normal aging. Secondary lysosomes as well as tertiary residual bodies (lysosomes/lipofuscin) increased implying stimulated, autophagocytosis and lysosomal system activation. Less affected brain regions, such as the thalamus, displayed similar though less extensive alterations. Certain thalamic neurons exhibited a distinctive lysosome-related abnormality characterized by the presence of cell surface blebs of varying size and number filled with intense hydrolase immunoreactivity. At more advanced stages of degeneration in still intact neurons, hydrolase-positive lipofuscin, particularly in the form of abnormal large aggregates, nearly filled the cytoplasm. Similar lipofuscin aggregates were oberved in abundance in the extracellular space following cell lysis and were usually associated with deposits of the β-amyloid protein. Degenerating neurons and their processes were the major source of these aggregates within senile plaques which contained high concentrations of acid hydrolases. We have shown in previous studies that these lysosomal hydrolases in plaques are enzymatically-active. The persistence of lysosomal structures in the brain parenchyma after neurons hyve degenerated is a striking and potentially diagnostic feature of Alzheimer disease which has not been observed, to our knowledge, in other degenerative diseases. The lysosomal response in degerating Alzheimer neurons represents a probable link between an early activation of the lysosomal system in at-risk, normal-appearing neurons and the end-stage contribution of lysosomes to senile plaque formation of emphasizes a slowly progressive disturbance of the lysosomal system throughout the development of Alzheimer disease.  相似文献   
65.
颈动脉支架置入术治疗颈动脉狭窄   总被引:23,自引:2,他引:21  
颈动脉支架置入术(CS)作为一种治疗颈动脉狭窄(CAS)的新方法,与传统的颈动脉内膜剥离术相比较,具有易操作、创伤小、并发症低等优点,作者就CS的现状、操作方法及并发症处理作一综述。  相似文献   
66.
目的探讨颈动脉粥样硬化脑梗死的相关性。方法60例脑梗死患,均经头颅CT证实,年龄在48~72岁之间,采用SONELINE VersaPro彩色多普勒超声诊断仪,诊断颈动脉粥样斑块增厚情况及颈动脉狭窄程度。结果有22例颈动脉内粥样斑块合并颈动脉中重度狭窄,占37%;全部22例颈动脉中重度狭窄的病例中有19例同侧有脑梗死,占86%。结论颈动脉超声检查对脑梗死的临床治疗和预防具有重要意义。  相似文献   
67.
目的 探讨血管平滑肌细胞及Bcl 2和Bax蛋白表达在自发性高血压大鼠 (SHR)颈动脉血管间质胶原重构及逆转中的意义。方法 选择 16周龄雄性SHR各 12只分别为厄贝沙坦组 (30mg·kg- 1·d- 1 )和非厄贝沙坦组 ,另选同龄雄性Wistar大鼠 12只为正常对照组 ;颈总动脉切片采用HE染色、苦味酸一天狼星红 (PSR)染色、免疫组化法染色和末端脱氧核苷酸转移酶介导dUIP缺口末端标记法分别检测颈动脉壁厚 腔径比值、胶原面积百分比、Bcl 2和Bax蛋白表达和血管平滑肌细胞 (VSMC)凋亡率(APOI)。结果 非厄贝沙坦组颈动脉壁厚 腔径比值较正常对照组高 2 5 0 .11%± 15 .6 3% (P <0 .0 1) ,厄贝沙坦组治疗 2 0周后 ,较非厄贝沙坦组下降了 4 3.2 4 %± 8.6 2 % (P <0 .0 1) ;非厄贝沙坦组胶原面积百分比较正常对照组SBP高 2 0 1.6 7%± 16 .73% (P <0 .0 1) ,厄贝沙坦组治疗 2 0周后 ,较非厄贝沙坦组仅仅下降了 17.70 %± 6 .4 5 % (P <0 .0 1) ;非厄贝沙坦组的VSMC率APOI较正常对照组显著增高 ,经药物治疗后下降 ;非厄贝沙坦组的VSMCBcl 2蛋白表达阳性率明显高于正常对照组 ,用厄贝沙坦治疗后 ,VSMCBcl 2阳性率较非厄贝沙坦组明显减少 ;非厄贝沙坦组和正常对照组的VSMCBax蛋白表达阳性率无明显差别 ,用厄贝沙坦治疗后 ,VS  相似文献   
68.
目的通过分析颈动脉粥样硬化与冠心病的关系探讨颈动脉超声对诊断冠心病的临床意义。方法将120例入选对象分为对照组,稳定性心绞痛(SA)组,不稳定性心绞痛(UA)组,急性心肌梗死(AMI)组,每组30例,分别给予超声检测颈动脉内-中膜厚度(IMT),同时测定3组冠脉造影结果:正常组21例,单支病变组18例,多支病变组29例。结果冠心病患者IMT较正常对照组有显著增厚(P<0.01),且冠脉造影正常组与单支、多支病变组间亦存在显著性差异(P<0.05)。结论颈动脉超声检测对冠心病的预测具有确切的临床意义。  相似文献   
69.
颈动脉支架治疗颈动脉狭窄的并发症   总被引:2,自引:0,他引:2  
目的 探讨颈内动脉狭窄血管内支架治疗的并发症.方法 对648例颈内动脉狭窄患者行全脑血管造影及颈部超声检查.365例患者使用脑保护装置,283例未使用保护装置283例.结果 648例患者技术成功率为100%,患者症状消失或好转率为78.7%.心率<50次/min者占26.4%;术中栓子脱落5例,其中3例治疗后恢复,2例遗留一侧肢体运动障碍,术后颅内出血死亡3例,术后30 d内总脑卒中或死亡6例,占1.2%.随访率为77 8%.再狭窄17例,占3.3%.结论 颈内动脉狭窄的血管内支架治疗是安全的,但术前对临床及影像学检查正确评价,术中规范化操作及术后规范化护理,是减少并发症的关键.  相似文献   
70.
滕乐群  沈晨阳 《中国卒中杂志》2007,15(10):1128-1133
颈动脉狭窄会导致患者远期认知功能下降,而既往研究表明颈动脉内膜剥脱术和支架
置入术作为治疗颈动脉狭窄的主要术式,可以改善患者的认知功能,尤其是执行能力等特定领域的
认知水平。进一步研究发现颈动脉血管重建术中栓子的形成,术后脑血流灌注提高,以及神经代谢
水平等改变可能在机制上解释颈动脉重建术后认知功能的变化;此外,围术期炎症反应,血脂水平,
以及基因易感性等都是术后远期认知功能结局的临床预测因素,以上因素对于提高颈动脉狭窄患者
的生活质量、治疗术式的优化具有重要临床意义。  相似文献   
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