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111.
Normal cerebral perfusion measurements using arterial spin labeling: reproducibility, stability, and age and gender effects. 总被引:4,自引:0,他引:4
Laura M Parkes Waqar Rashid Declan T Chard Paul S Tofts 《Magnetic resonance in medicine》2004,51(4):736-743
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males. 相似文献
112.
小剂量阿司匹林对缺血性脑血管病患者血小板聚集功能的影响 总被引:1,自引:0,他引:1
目的 :观察小剂量阿司匹林 (ASA)对ICVD患者血小板聚集功能的影响。方法 :用花生四烯酸 (AA ,5 0 0 μmol·L-1)、二磷酸腺苷 (ADP ,5 μmol·L-1)、肾上腺素 (EPN ,5 μmol·L-1)和胶原 (COL ,2 μg·mL-1)做诱导剂检测ICVD患者服用不同剂量ASA组 ( 2 5、5 0和10 0mg·d-1)的血小板聚集率。结果 :各ASA组对AA、COL诱导聚集的变异系数较大。对AA诱导聚集无显著抑制者的比例分别为2 5mg·d-1组 44 4%、5 0mg·d-1组 2 9 6%、10 0mg·d-1组 2 9% ,其中 5 0mg·d-1组中合并糖尿病的例数较显著抑制者中多。结论 :ICVD患者中小剂量ASA作用个体差异较大 ,部分与自身危险因素有关。提示临床中ASA的效果需要实验室检测并应个体化 相似文献
113.
脑梗死急性期对血压和颅压的控制极为重要,若措施得当,可大大降低病死率和致残率。笔者结合临床工作经验总结体会如下:脑梗死急性期对血压和颅压的控制极为重要,若措施得当,可大大降低病死率和致残率,笔者结合临床工作经验总结体会如下。 相似文献
114.
大脑中动脉动脉瘤的血管内治疗 总被引:3,自引:3,他引:0
目的探讨血管内治疗大脑中动脉动脉瘤的可行性、安全性和有效性。方法回顾性分析采用血管内治疗的24例大脑中动脉动脉瘤患者的临床资料,包括患者年龄、临床分级、动脉瘤出血量、部位、形态、瘤颈宽度、血管痉挛程度及术中应用技术等。结果100%栓塞17例,95%栓塞4例,90%栓塞3例。1例患者术中血管痉挛加重致不完全失语。随访无动脉瘤再破裂出血病例,1例患者出现迟发性血管痉挛。结论血管内治疗大脑中动脉动脉瘤是一种安全、有效的方法。 相似文献
115.
Pinacidil抑制线粒体和死亡受体通路减少大鼠脑缺血再灌注后神经元凋亡(英文) 总被引:4,自引:1,他引:3
目的探讨ATP敏感性钾通道开放剂pinacidil对大鼠脑缺血再灌注后神经元凋亡的保护作用及信号转导机制。方法 100 只Wistar 雄性大鼠随机分为四组:A 组(假手术组)、B组 (缺血组)、C 组 (KATP开放剂处理组)及D组 (KATP开放剂和阻断剂处理组)。用线栓法制备大鼠大脑中动脉缺血(middle cerebral artery occlusion,MCAO)模型,用DNA断端末端标记法(terminal-deoxynucleotidytransferase-mediated dUTP-biotin nick end labeling,TUNEL)检测神经元凋亡,用原位杂交方法检测caspase-3、caspase-8及caspase-9 mRNA的表达。结果 (1) C组12 h、24 h、48 h、72 h 时间点的凋亡细胞数较 B、D 组显著减少(P<0.05 或 P<0.01) ;B 组和 D组之间无显著性差异(P>0.05)。(2) C 组 caspase-3 mRNA 和 caspase-8 mRNA 在各时间点及 caspase-9 mRNA 在 12 h、24 h、48 h、72h 时间点的表达显著少于B组和D组(P<0.01或P<0.05),B组和D组之间无显著性差异(P>0.05)。结论 KATP通道开放剂能显著减少大鼠脑缺血再灌注后的细胞凋亡及caspase-3、caspase-8及caspase-9 mRNA的表达。KATP通道开放剂可能通过抑制线粒体通路和死亡受体通路降低神经元凋亡,保护缺血再灌注损伤后的脑组织。 相似文献
116.
目的 探讨高龄急性脑梗死患者接受阿替普酶静脉溶栓治疗有效性、安全性和临床预后的影响
因素。
方法 前瞻性连续纳入江苏省苏北人民医院2016年9月-2018年9月收治入院进行阿替普酶静脉溶
栓治疗的急性脑梗死患者,按照年龄将患者分为年龄≥80岁组和年龄<80岁组。比较两组患者入院
时、溶栓24 h NIHSS评分,6个月mRS评分及死亡率,观察两组溶栓相关出血转化、症状性颅内出血及
肺部感染的发生情况。应用多因素Logistic回归分析观察所有患者静脉溶栓预后的独立影响因素。
结果 最终共纳入患者119例,男性69例(58.0%),年龄范围46~94岁,平均70.12±10.55岁,入院
NIHSS评分4~38分。其中年龄≥80岁患者29例,年龄<80岁患者90例。静脉溶栓后,两组患者溶栓
24 h NIHSS评分较入院时均明显降低(均P<0.05),两组治疗24 h NIHSS评分比较差异无统计学意义;
两组的出血转化、症状性颅内出血、肺部感染、6个月预后良好及死亡率比较,差异均无统计学意义。
多因素Logistic回归分析显示,入院到静脉溶栓时间、入院时NIHSS评分及肺部感染是脑梗死静脉溶
栓6个月预后的独立危险因素(P<0.05),高龄不是影响预后的因素(P>0.05)。
结论 高龄急性脑梗死患者静脉溶栓治疗安全有效,未增加颅内出血转化风险、死亡率及不良预
后。入院到静脉溶栓时间、入院时NIHSS评分及肺部感染是急性脑梗死患者静脉溶栓6个月预后不良
的独立危险因素。 相似文献
117.
The Hemodynamic Mechanisms of Lung Injury and Systemic Inflammatory Response Following Brain Death in the Transplant Donor 总被引:7,自引:2,他引:5
Vassilios S. Avlonitis Christopher H. Wigfield John A. Kirby John H. Dark 《American journal of transplantation》2005,5(4):684-693
Brain-dead donors are the major source of lungs for transplantation. Brain death is characterized by two hemodynamic phases. Initially, massive sympathetic discharge results in a hypertensive crisis. This is followed by neurogenic hypotension. Up-regulation of pro-inflammatory mediators occurs in all organs and lung injury develops; this can adversely affect graft function post-transplantation. The mechanisms of the systemic and lung inflammation are unknown. We hypothesized that the hemodynamic changes are responsible for these inflammatory phenomena. Brain death was induced by intra-cranial balloon inflation in rats. This resulted in hypertensive crisis, followed by hypotension. There was a significant increase in blood neutrophil CD11b/CD18 expression and pro-inflammatory cytokine levels in serum and bronchoalveolar lavage, compared with control animals. Rupture of the capillary-alveolar membrane was demonstrated by electron microscopy. Elimination of the hypertensive response by α-adrenergic antagonist pre-treatment prevented inflammatory lung injury, reduced the systemic inflammatory markers and preserved capillary-alveolar membrane integrity. Correction of the neurogenic hypotension with noradrenaline ameliorated the systemic inflammatory response and improved oxygenation. We conclude that the sympathetic discharge triggers systemic and lung inflammation, which can be further enhanced by neurogenic hypotension. Management of the brain-dead donor with early anti-inflammatory treatment and vasoconstrictors is warranted. 相似文献
118.
Objective To observe the effect of electro-acupuncture combined with early rehabilitation on the motor function and expressions of the adhesion molecules CD11b and CD18 in the polymorphonuclear leucocytes (PMN) and monocytes and serum tumor necrosis factor-α (TNF-α) levels in patients with acute cerebral infarction (ACI). Methods A total of 165 ACI patients were randomly divided into control group (group A, n=50), conventional rehabilitation group (group B, n=50) and comprehensive rehabilitation group (group C, n=65). The expressions of CD11b and CD18 in the PMN and monocytes and serum TNF-α levels were determined before and at 1, 2, and 4 weeks after the treatment. Thirty-two healthy subjects were also recruited as the normal control group (group N). The neurological function of the subjects was evaluated by modified Edinburgh-Scandinavia stroke scale (MESSS) and Fugi-Meyer Assessment (FMA), and their activity of daily living (ADL) was assessed using Barthel index (BI). Results The CD11b/CD18 expression in the PMN and MN and serum TNF-α level in groups A, B and C were significantly higher than those in group N before and 1 week after the treatment (P<0.05). CD11b/CD18 expression and serum TNF-α level were significantly lower in groups B and C than in the group A at 1 week after the treatment, and significantly lower in group C than in group B (P<0.05). At 2 weeks of treatment, CD11b/CD18 and TNF-α were significantly lower in groups B and C than in the group A, being the lowest in group C (P<0.05). The scores of mESSS in both groups B and C were lower than that in group A, and the scores were lower in group C than in group B. Group C showed higher FMA scores than group B, both having higher scores than group A. At 4 weeks of treatment, the mESSS scores were significantly lower, hut the FMA and ADL score significantly higher in groups B and C than in the control group (P<0.05), and the differences were more obvious in group C. Groups B and C had greater effective rate than group A (P<0.05), and the rate was the highest in group C (P<0.05). Conclusion Electro-acupuncture combined with early rehabilitation promotes the recovery of motor function in ACI patients probably by regulating the expressions of the adhesion molecules CD11b and CD18 on the PMN and monocytes and the serum levels of TNF-α. 相似文献
119.
细胞黏附分子(ICAM-1)在大鼠弥漫性脑损伤中的表达意义 总被引:1,自引:0,他引:1
目的探讨ICAM—1在大鼠弥漫性脑损伤中的表达及意义。方法采用Marmarou方法获得大鼠弥漫性脑损伤模型.实时定量RT—PCR、S—P免疫组化法分别测定ICAM—1蛋白和mRNA在外伤后不同时间点的表达变化.干湿重法测脑组织含水量.组织切片苏木精一伊红染色观测炎性细胞浸润情况。结果外伤组与假手术对照组比较,ICAM—1蛋白表达分别于伤后6h明显升高.72h达到高峰(P〈0.05),ICAM—ImRNA表达3h即明显升高,72h达最高峰,其后下降。7d时仍高于假手术对照组(P〈0.01)。伤后脑组织含水量较假手术对照组高,同时炎性细胞大量聚集。结论大鼠脑外伤诱导了ICAM—1的表达.ICAM—1通过介导炎性细胞的浸润可能参与了伤后脑水肿的形成过程. 相似文献
120.
目的观察高血压脑出血(ICH)患者血肿周围血-脑屏障葡萄糖转运蛋白1(GLUT1)表达的变化。方法采用免疫组化方法检测28例高血压ICH患者不同病程血肿周围脑组织GLUT1的表达情况。结果与对照组相比,ICH组发病12 h GLUT1表达开始增强,24 h、48 h表达最强(均P<0.01);72 h表达明显下降(P<0.01)。结论ICH早期血肿周围GLUT1表达增多,有助于恢复脑的能量代谢。 相似文献