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31.
上矢状窦旁脑膜瘤致上矢状窦阻塞时侧支静脉通路的意义   总被引:9,自引:2,他引:7  
目的 分析上矢状窦旁脑膜瘤致上矢状窦(SSS)阻塞时其侧支静脉通路的建立情况,确定其在肿瘤切除术中的意义。方法 总结归纳86例上矢状窦旁脑膜瘤行MRA及DSA检查时的静脉系表现。结果 27例发生SSS完全阻塞,59例部分阻塞。18例在阻塞的SSS周围出现了由表浅皮层静脉所形成的侧支静脉环;通过表浅皮层静脉与蝶顶窦及小脑幕静脉系建立端—端吻合的16例;通过与Troland或Labbe静脉建立吻合的14例;通过大脑镰与下矢状窦吻合的9例;通过脑膜静脉并经板障静脉引流到颈外静脉系的17例;混合型12例。结论 上矢状窦旁脑膜瘤致SSS阻塞时,肿瘤周围存在广泛侧支静脉通路,术中应注意保护。脑DSA及MRA检查对术前了解SSS通畅性及侧支静脉通路建立有帮助。  相似文献   
32.
AIMS: This study evaluates feasibility, safety, and efficacy of magnetic remote-controlled accessory pathway (AP) ablation. METHODS AND RESULTS: The novel magnetic navigation system (MNS) (Niobe, Stereotaxis) creates a steerable magnetic field (0.08 T) controlling the distal magnetic tip of an ablation catheter. In conjunction with a catheter advancer system (Cardiodrive, Stereotaxis) remote catheter ablation is enabled. Conventional electrophysiology study identified AP conduction in 59 patients (37 males, 36+/-14 years, 60 APs). First generation 1-magnet tip (1-M) (group I, n=18), second generation bipolar 3-magnet tip (3-M) (group II, n=27), and third generation quadripolar 3-magnet tip catheters (3-M quad.) (group III, n=14) were used for magnetic remote-controlled ablation. Successful AP ablation was achieved in 67% (group I), 85% (group II), and 92% (group III). A significant decrease of median [IQR: Q1-Q3] fluoroscopy time and dosage was observed: 21.2 [12.1-33.8] min, 1110 [395-3234] microGym2 (group I); 6.5 [4.4-15.4] min, 290 [129-489] microGym2 (group II), and 4.9 [3.4-8.0] min, 129 [74-270] microGym2 (group III). Mean procedure time (217+/-67 min; 182+/-68 min, and 172+/-90 min) significantly decreased in group III. Median number [Q1-Q3] of radiofrequency current applications in groups I, II, and III was 4 [2-9], 4 [2-6], and 2 [2-4], respectively. No complications occurred. CONCLUSION: Remote AP ablation is safe and feasible using the novel MNS. Introduction of the 3-magnet quadripolar ablation catheter significantly improved the efficacy of the procedure.  相似文献   
33.
Menthol glucuronide was isolated from the urine of a healthy 70-kg female subject following ingestion of 400 mg of peppermint oil and 6 g of 99% [U-(13)C]glucose. Glucuronide (13)C-excess enrichment levels were 4-6% and thus provided high signal-to-noise ratios (SNRs) for confident assignment of (13)C-(13)C spin-coupled multiplet components within each (13)C resonance by (13)C NMR. The [U-(13)C]glucuronide isotopomer derived via direct pathway conversion of [U-(13)C]glucose to [U-(13)C]UDP-glucose was resolved from [1,2,3-(13)C(3)]- and [1,2-(13)C(2)]glucuronide isotopomers derived via Cori cycle or indirect pathway metabolism of [U-(13)C]glucose. In a second study, a group of four overnight-fasted patients (63 +/- 10 kg) with severe heart failure were given peppermint oil and infused with [U-(13)C]glucose for 4 hr (14 mg/kg prime, 0.12 mg/kg/min constant infusion) resulting in a steady-state plasma [U-(13)C]glucose enrichment of 4.6% +/- 0.6%. Menthol glucuronide was harvested and glucuronide (13)C-isotopomers were analyzed by (13)C NMR. [U-(13)C]glucuronide enrichment was 0.6% +/- 0.1%, and the sum of [1,2,3-(13)C(3)] and [1,2-(13)C(2)]glucuronide enrichments was 0.9% +/- 0.2%. From these data, flux of plasma glucose to hepatic UDPG was estimated to be 15% +/- 4% that of endogenous glucose production (EGP), and the Cori cycle accounted for at least 32% +/- 10% of GP.  相似文献   
34.
The aim of this review article is to discuss the electrocardiographic presentation of the so called variants of pre‐excitation (“Mahaim fibers”) during sinus rhythm and tachycardia.  相似文献   
35.
目的为了解旁道位置与室上性心动过速初次发作时年龄及性别的关系.方法对128例已进行过射频消融的患者进行了回顾性分析.结果男性左侧旁道发病时平均年龄大于右侧及中隔旁道平均为14岁和9岁;大于女性左侧旁道7岁,男性显性旁道发病时平均年龄小于隐匿性旁道7岁.而女性显性旁道与隐匿性旁道、左侧旁道与右侧旁道发病时平均年龄无显著性差异.结论旁道位置与室上速初次发作时年龄及性别有关.  相似文献   
36.
Catheter Ablation Techniques in AVNRT. Radiofrequency catheter ablation has been established as a first-line curative treatment modality in patients with symptomatic AV nodal reentrant tachycardia (AVNRT). The successful sites of stepwise catheter ablation approaches of the so-called fast and slow pathways strongly suggest that AVNRT involves the atrial approaches to the AV node. The typical fast pathway ablation sites are located anterosuperior toward the apex of the triangle of Koch, which also contains the compact AV node, whereas the usual slow pathway ablation sites are located posteroinferior toward the base of the triangle of Koch at a greater distance to the compact AV node and bundle of His. Accordingly, ablation studies with large patient cohorts have demonstrated that fast pathway ablation carries a higher risk of inadvertent complete AV block. Thus, the slow pathway is clearly the primary target site, and fast pathway ablation is rarely necessary. Different approaches for slow pathway ablation have been elaborated: anatomically oriented stepwise techniques, ablation guided by double potentials recorded within the area of the slow pathway insertion, and combined techniques. The modern concept of AVNRT suggests that this arrhythmia involves the highly complex three-dimensional nonuniform anisotropic AV junctional area. Accordingly, mapping and ablation studies demonstrated that the anterior approach is not identical with fast pathway ablation, and the posterior approach is not identical with slow pathway ablation. Therefore, it is essential for interventional electrophysiologists to familiarize themsdves with the anatomic and electrophysiologic details of this complex and variable specialized AV junctional region. In this review, the anatomic and pathophysiologic aspects of the AV junctional area as they relate to interventional therapy are summarized briefly, and the catheter techniques for ablation of the so-called fast and slow AV nodal pathways for the treatment of AVNRT are described.  相似文献   
37.
应用单向免疫扩散法测定了流行性出血热(EHF)患者的7种补体成份和血浆素原(Pg).结果表明,CT脂酶抑制剂在少尿期、多尿期和恢复期均高于正常(P<0.01);补体C_1q在多尿期高于正常(P<0.01);补体C_4在发热期和少尿期低于正常(P<0.01),以后逐渐恢复正常;补体C_3,C_5和C_9的变化与C_4相似;B因子在少尿期低于正常(P<0.01),在多尿期高于正常(P<0.05);Pg始终高于正常水平但在少尿期有回降.说明EHF患者不仅有补体经典途径的识别阶段、活化阶段和膜攻击阶段的变化,而且亦有旁路激活,其活化程度与病情有关.  相似文献   
38.
We identified and characterized a neurodifferentiation compound from the marine brown alga Sargassum fulvellum collected from the Japanese coastline. Several instrumental analyses revealed the compound to be pheophytin a. Pheophytin a did not itself promote neurite outgrowth of PC12 cells. However, when PC12 cells were treated with a low concentration of pheophytin a (3.9 microg/ml) in the presence of a low level of nerve growth factor (10 ng/ml), the compound produced neurite outgrowth similar to that produced by a high level of nerve growth factor (50 ng/ml). Pheophytin a also enhanced signal transduction in the mitogen-activated protein kinase signaling pathway, which is also induced by nerve growth factor. The effect of pheophytin a on neurite outgrowth of PC12 cells was completely blocked by U0126, a representative mitogen-activated protein kinase kinase inhibitor. These results suggest that pheophytin a enhances the neurodifferentiation of PC12 cells in the presence of a low level of nerve growth factor and that this effect is mediated by activation of a mitogen-activated protein kinase signaling pathway.  相似文献   
39.
目的鉴定参与线虫衰老的神经内分泌调控的新基因。方法鉴于神经系统在衰老调控中的重要作用,通过寿命分析和脂褐质自发荧光的检测,从编码突触蛋白的遗传位点中筛选参与衰老调控的基因。我们还进一步检查了这些遗传位点相应的突变体的永久性幼虫形成情况,探讨它们是否可能受胰岛素样信号通路的调控。结果遗传位点 unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1,unc-13,sbt-1,unc-64 可能参与线虫衰老的调控。而且在衰老的调控中,unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1 的功能可能与unc-13,sbt-1,unc-64相反。肠道脂褐质自发荧光的检测进一步证明了筛选出的各基因对应突变体的长寿或短寿表型,是由减慢或缩短的组织衰老所致。在筛选出的基因中,syd-2,hlb-1,mkk-4,scd-2,snb-1,ric-4,unc-64 也参与了永久性幼虫形成的调控。另外,daf-2突变增强了syd-2和hlb-1的表达,降低了mkk-4,nrx-1,ric-4,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达。daf-16突变提高了syd-2和 hlb-1 的表达,降低了mkk-4,nrx-1,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达. 结论突触功能可能在个体寿命和永久性幼虫形成的调控机制中具有重要的作用。  相似文献   
40.
目的探讨护理管理路径在应用佩尔地平治疗的重度子痫前期病人的效果,以期达到最佳的治疗效果,并减少并发症的发生。方法将用佩尔地平针治疗的重度子痫前期的病人486例随机分为两组,一组按常规护理,另一组按制定的护理管理路径护理。结果患者依从性对照组为168例,占70%;观察组为228例,占92.68%,P〈0.05,其差异有统计学意义。胎死宫内发生率对照组为9.16%,观察组为0.81%,P〈0.05,其差异有统计学意义。血压的稳定性对照组为36.3%,观察组为97.6%,P〈0.05,其差异有统计学意义。结论护理管理路径可以提高重度妊娠高血压疾病的治疗效果,减少并发症的发生。  相似文献   
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