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121.
目的我们应用平衡法门控心血池显像技术对不同Killip分级的前壁心肌梗死患者进行左室总体和局部收缩和舒张功能参数的对比分析。方法对照组15例(G0),前壁心肌梗死KillipⅠ级17例(G1),前壁心肌梗死KillipⅡⅢ级12例(G2)。利用平衡法门控心血池显像技术评价3组的左室总体和局部的收缩与舒张功能。结果①左室整体收缩功能,在LVEF,ESC 2个参数中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。在PER、1/3EF、1/3ER 3个参数中,G2分别比G1和G0显著下降(P<0.05)。②左室总体舒张功能,在PFR、1/3FF、1/3FR、EDC中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。③左室局部收缩功能,在以LVREF为参数时,G1在4个节段比G0显著差异(P<0.05),G2在所有6个节段中比G1和G0均显著下降(P<0.05)。④左室局部舒张功能,在以LVR1/3FF为参数时,G1在4个节段比G0显著下降(P<0.05),G2在所有6个节段比G0和G1均显著下降(P<0.05)。结论前壁心肌梗死后出现心功能受损或心力衰竭的主要原因为左室重构。  相似文献   
122.
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   
123.
In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method.  相似文献   
124.
125.
AIMS: To evaluate the relationship between echocardiographic cardiac function and outcome in patients with stable symptomatic angina. METHODS: Baseline echo left ventricular ejection fraction and volume data measured in a central laboratory was available for 7016 patients (92% of the total) participating in the ACTION trial (A Coronary disease Trial Investigating Outcome with Nifedipine GITS). Ejection fraction was also measured by investigators. Evaluation of the different echocardiographic variables was based on adjusted hazard ratios comparing the unfavourable limit of the 90% range of the variable concerned to the favourable limit. RESULTS: The centrally measured ejection fraction was the most powerful predictor of all-cause death (adjusted hazard ratio=2.5), myocardial infarction, any stroke or transient ischaemic attack and overt heart failure (adjusted hazard ratio=4.5). The addition of either end systolic volume or end diastolic volume to ejection fraction did not materially affect the power of prediction. Compared to the central ejection fraction measurement, the investigator-measured ejection fraction was a less powerful predictor for all outcomes considered. CONCLUSION: Routine echocardiography carefully analysed by standardised methods provides useful prognostic information in patients with stable angina, including for total mortality.  相似文献   
126.
This article presents a review on the efficacy of surgical ventricular restoration and direct surgery for ventricular tachycardia in patients with left ventricular aneurysm or dilated ischemic cardiomyopathy. The procedure includes a non-electrophysiologically guided subtotal endocardiectomy and cryoablation in addition to endoventricular patch plasty of the left ventricle. Coronary artery bypass surgery and mitral valve repair are performed concomitantly as needed. In our experience, this procedure yielded a 90% success rate in terms of freedom from spontaneous ventricular tachycardia, with an early mortality rate of 3.8%. A practical guide to the pre- and postoperative management of these patients is provided. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   
127.
鱼腥草注射液佐治下呼吸道感染的疗效观察   总被引:1,自引:0,他引:1  
目的观察鱼腥草注射液佐治下呼吸道感染的疗效及安全性.方法将76例急性下呼吸道感染患者随机分为治疗组和对照组,两组均予内科常规治疗,治疗组则另予鱼腥草注射液治疗.结果治疗组的总有效率为94.7%,显著优于对照组的73.7%(x2=6.33,P<0.05),且未见明显副作用.结论鱼腥草注射液佐治急性下呼吸道感染安全、有效,值得推广.  相似文献   
128.
肝移植术后并发胆道狭窄和胆泥淤积影像诊断及介入治疗   总被引:1,自引:0,他引:1  
目的:评价肝移植术后胆道狭窄和胆泥淤积影像诊断及介入治疗的价值。方法:对39例肝移植术后并发胆道狭窄和胆泥淤积的影像诊断及介入治疗进行回顾性分析。结果:超声、T型管胆道造影、CT和MRI检查诊断胆道狭窄伴胆泥形成39例,38例介入治疗后胆道梗阻症状明显缓解;1例介入治疗后胆道梗阻症状未明显改善,后行外科胆管修补术。结论:T型管胆道造影或直接经皮胆道造影对肝移植术后胆道狭窄和胆泥淤积诊断特异性及敏感性最高,放射介入和内镜介入技术对其均发挥重要的治疗作用。  相似文献   
129.
目的探讨单蒂横行腹直肌肌皮瓣乳房再造术中Ⅳ区皮瓣的取舍。方法通过16例实施单蒂横行腹直肌肌皮瓣乳房再造术,术中观察皮瓣的皮色、断面出血颜色,并利用近红外血氧监测仪测定皮瓣各区的组织血氧饱和度,决定Ⅳ区皮瓣的取舍。术后观察指标包括术后并发症及美学效果。结果16例中5例Ⅳ皮瓣的肤色正常、断面出血呈鲜红色而非暗红色、组织血氧饱和度不低于Ⅲ区组织血氧饱和度的95%。在接受了保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术后,再造乳房全部成活,无严重术后并发症,患者对再造乳房均很满意。结论近红外血氧无创检测有助于决定Ⅳ区皮瓣的取舍。有选择地实施保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术,可用于大面积胸壁缺损或乳腺尾叶的修复重建。  相似文献   
130.
碱性成纤维细胞生长因子在实验性硬脑膜重建中的应用   总被引:3,自引:0,他引:3  
[目的] 探讨碱性成纤维细胞生长因子( bFGF)在实验性自体筋膜硬脑膜重建中的应用价值.[方法]取 SD大鼠 35只,分成 5组.其中 A组 3只,直接将背部筋膜覆盖在硬膜外, B组 5只,采用自体筋膜硬脑膜重建模型,通过免疫组织化学方法观察这两组大鼠自体筋膜硬脑膜移植的愈合过程及细胞因子 bFGF在其中的表达; C组、 D组、 E组各 9只,分别进行自体筋膜硬脑膜重建, D组加用外源性 bFGF, E组仅用明胶海绵,通过脑脊液漏研究、免疫组织化学方法研究外源性 bFGF对自体筋膜重建硬脑膜愈合过程的影响并用 RT- PCR方法研究内源性 bFGF mRNA的表达情况.[结果] 大鼠自体筋膜移植硬脑膜部位 bFGF表达明显; C、 D、 E组大鼠重建硬脑膜抵抗脑脊液漏压力值( mmH2O)分别为 311± 75, 497± 153, 338± 88,Ⅰ型胶原纤维表达值分别为 4.9± 0.8, 10.9± 1.6, 5.3± 0.9, D组均好于对照组( P< 0.05);内源性 bFGF mRNA的表达没有明显变化.[结论] 在自体筋膜移植硬脑膜的愈合过程中 bFGF可能起了重要的作用;外源性 bFGF处理的大鼠其移植筋膜愈合要好于对照组.  相似文献   
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