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71.
Objectives Recent studies have described regional differences in the electrophysiology and pharmacology of ventricular myocardium in canine, feline, rat, guinea pig, and human hearts. This has been shown to be due to a smaller IKs and a lager sodium-calcium exchange current (INa-Ca) and late INa in M region (deep subepicardial to midmyocardial). Studies from our laboratory have found a new repolarization current-nonselective cation current (NSCCs) existing in rabbit right ventricular myocytes. Methods We examined the characteristics of NSCCs in epicardial, M region, and endocardial cells isolated from the rabbit left ventricle with standard microelectrode and whole-cell patch-clamp techniques. The permeability to Na , K , Li , Cs but not to Cl- indicating that it was a nonselective cation current. Gd3 (0.1 mmol/l) and La3 (0.1 mmol/l) can block the current markedly. Results Further characterization of NSCCs was significantly smaller in M cells than in epicardial and endocardial cells. NSCCs current density was significantly smaller in M cells than in epicardial and endocardial cells. With repolarization to -80 mV, INs current density was (-0.44±0.05) PA/PF in endocardial cells, (-0.12±0.05) PA/PF in M cells and (-0.28±0.07) PA/PF in epicardial cells; and with repolarization to 30 mV, INs current density was (1.09±0.29) PA/PF in endocardial cells, (0.38±0.09) PA/PF in M cells and (0.91±0.32) PA/PF in epicardial cells. Conclusions Transmural dispersion of repolarization was due to the heterogeneity of NSCCs in rabbit left ventricle epicardial, endocardial myocytes and M cells. These findings may advance our understanding of the ionic basis for our understanding of factors contributing to the development of cardiac arrhythmias.  相似文献   
72.
目的应用显微手术夹闭、血管内栓塞和栓塞后手术夹闭3种治疗方法,探讨治疗颅内破裂动脉瘤的安全有效方案。方法显微手术瘤颈夹闭30个动脉瘤,栓塞34个动脉瘤,栓塞后夹闭15个动脉瘤。结果夹闭组30个完全夹闭,无复发,死亡率6%(2/30)。栓塞组完全闭塞率70.6%(24/34),复发率17.6%(6/34),死亡率11.8%(4/34)。栓塞后手术组15个完全夹闭,无复发,死亡率6.7%(1/15)。治疗结束用GOS评价,1个月后3组良好率分别为80.0%、79.4%和80.0%;半年后良好率分别为90.0%、88.2%和86.7%。结论显微手术瘤颈夹闭术仍然是治疗破裂动脉瘤的有效方法,具有1次治疗彻底和复发率低的优势,并可作为栓塞失败的补救手段。  相似文献   
73.
74.
抽动障碍中医证型与血清单胺类物质的相关性研究   总被引:1,自引:0,他引:1  
目的 观察抽动障碍不同中医证型患者血清多巴胺、去甲肾上腺素等单胺类神经递质的水平,并探讨各证型之间血清神经递质的水平是否存在差别.方法 采用化学荧光法测定46例抽动障碍患者(病例组)血清多巴胺、去甲肾上腺素水平,并与40例正常儿童(对照组)进行比较.结果 病例组血清多巴胺为0.449μg/ml,对照组为0.210μg/ml;病例组血清去甲肾上腺素为0.227μg/ml,对照组为0.127μg/ml,两组各均值比较,病例组血清多巴胺和去甲肾上腺素均显著高于对照组.病例组外风侵袭、肝风内动型,或兼气郁化火型,或兼脾虚痰聚型,或兼阴虚风动型血清多巴胺水平分别为0.316、0.400、0.235、0.247μg/ml,四者比较有显著性差异;病例组符证型血清去甲.肾上腺素水平分别为0.203、0.224、0.144、0.154μg/ml,四者比较差异有显著性.结论 抽动障碍患者存在多巴胺和去甲肾上腺素水平异常,且各证型血清多巴胺、去甲肾上腺素水平有明显差异,而尤其以外风侵袭、肝风内动兼气郁化火型水平最高.  相似文献   
75.
综合实践教学模式的实施与护生综合能力的培养   总被引:3,自引:0,他引:3  
目的在《护理学基础》教学中,运用整体护理思维,探讨课堂综合实践教学模式的实效性,以提高护生的职业素质和能力。方法随机确定实验班和对照班,对照班采取传统的实践教学模式授课,实验班采取小群体综合实践模式教学。结果实验班护生的规范操作能力、沟通能力和知识运用能力与对照班比较有显著提高。结论小群体综合实践教学模式对护生综合能力的培养具有实际意义。  相似文献   
76.
Objective To explore the changes of craving and neuro-electrophysiological reactions under the exposure of heroin-related cues in abstinent heroin dependents.Methods In this self-controlled study,382 abstinent heroin dependent patients watched video of heroin smoking and injecting situations,and in the meantime were exposed to herein simulacrum and apparatus after relaxation exercises.The neuroelectrophysiological reactions were mcagured with a multi-biofeedback instrument before and after the cue exposed.Self-reported craving was also assessed before and after cue exposed.Results The craving were increased[(18±22)mm vs.(29±29)mm,P<0.01]after cue exposures compared to pre-exposure,EMG[(12±7)μN vs.(14±10)μV,P<0.01]and SC[(6.8±4.3)μS vs.(7.4±4.3)μS,P<0.01]also increased.But the percentages of δ,θ,α,SMR,low β,high β decreased compared to that under the cue exposures[8:(10.8±4.7)%vs.(9.7±4.4)%,P<0.01;0:(6.8±2.0)%vs.(6.3±2.0)%,P<0.01;α:(4.8±1.8)%vs.(4.5±1.7)%,P<0.01;SMR:(3.0 ±1.2)%vs.(2.8±1.2)%,P<0.01;low β:(2.6±1.1)%vs.(2.5±1.1)%,P<0.01 and high β:(4.6 ±1.5)%vs.(4.5±1.5)%.P<0.05].Conclusions The results indicate that drug-related cue induce heroin craving and electrophysiological reactions.  相似文献   
77.
Purpose: To evaluate the feasibility, reliability and analgesia effect of topical anesthesia combined with subconjunctival anesthesia in anti-glaucomatous surgery.Methods: Two hundred and four cases (357 eyes) underwent anti-glaucomatous surgeries under topical anesthesia with 0.5% Alcaine eye drops combined with subconjunctival anesthesia with 2% Lidocaine. The analgesic effect was analysed with visual analogue pain scale.Results: Among all of 357 eyes, 62 eyes underwent peripheral iridectomy, 67 eyes underwent simple trabeculectomy, 167 eyes underwent compound brabeculectomy and 12 eyes nonpenetrating trabecular surgery. The effects of anesthesia were as follows: 304 eyes (85.2%) were painless (Grade Ⅰ), 50 eyes (14.0%) were slight painful (Grade Ⅱ), and 3 eyes (0.8%) were more painful (Grade Ⅲ) during surgery. And no severe complications were observed in all the cases during surgery and postoperatively. Amaurosis fugax was not observed in the glaucoma patients at the late stage with narrow vi  相似文献   
78.
Graves病介入栓塞治疗的病理研究   总被引:1,自引:1,他引:0  
目的观察Graves病栓塞后的甲状腺组织动态病理变化。方法15例甲状腺动脉150 mm聚乙烯醇(PVA)微粒及平阳霉素栓塞治疗的Graves病患者,于术前、术后7天、3个月、6个月、1年、3年分别行甲状腺穿刺活检,共行44次穿刺活检,其中动脉栓塞术前15例、栓塞术后7天2例、3个月3例、6个月6例、1年5例次、3年13例次。结果栓塞后7天主要表现为凝固性坏死;栓塞后3-6个月表现为纤维组织增生变性和淋巴细胞浸润,滤泡灶性坏死为主;栓塞后1-3年主要表现为间质纤维组织增生明显和滤泡萎缩,部分散在增生滤泡被纤维间质分隔包裹,难以形成腺小叶结构,滤泡周围血管网减少。结论经甲状腺动脉栓塞治疗Graves病,甲状腺组织的病理变化是在栓塞后近期内主要表现为急性缺血坏死,然后表现为持续的慢性炎性破坏、滤泡萎缩、部分滤泡增生被明显增生的纤维组织分隔包裹的变化过程。提示微循环栓塞能肯定地破坏甲状腺组织,达到治疗Graves病较好的疗效。  相似文献   
79.
超声引导下VacoraTM旋切系统的实验研究   总被引:1,自引:0,他引:1  
目的探讨VacoraTM真空辅助活检系统的准确性和安全性,为临床应用奠定基础。方法选用里脊肉和鱼丸作为实验材料,根据鱼丸大小将实验分为5组:0.5、0.8、1.0、1.5及2.0cm组,每组鱼丸3~5个。采用VacoraTM活检系统,先行灰阶超声扫查肌肉后将鱼丸置入肌肉中,超声扫查置入的鱼丸,同轴套管针在超声引导下插入鱼丸底部,在套管针引导和超声监视下行旋切真空抽吸术;旋切后取出采样腔内的组织标本,用超声检查肌肉内的残腔,确定无鱼丸残留声像图。结果每次旋切组织条比较完整,其大小为20.0mm×0.6mm,旋切次数随鱼丸大小的增加而增加;0.5、0.8、1.0、1.5及2.0cm组里脊肉内鱼丸全部切除的平均旋切次数分别为12、15、19、26和31。所用的平均时间分别为15、18、23、27和34min。结论VacoraTM真空辅助活检系统定位准确、取样完整、操作简便。可为良恶性病变的诊断提供足够量的病理检查标本,为良性病变的完全切除提供具有潜在价值的手段。  相似文献   
80.
The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram in the same animals under similar laboratory conditions. Thiopental–isoflurane (TI), medetomidine–ketamine (MK), and xylazine–ketamine (XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker (P-FL) responses. For S-ST (2.5 cd s/m2), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m2), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be advantageous to use rather than TI for clinical studies.  相似文献   
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