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41.
Ofer Binah Irit Rubinstein Arieh Bomzon Ori S. Better 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(2):160-165
Summary The effects of sodium salts of various bile acids on the contractile force and the electrophysiological properties of rat ventricular muscle were studied in vitro. Primary, conjugated, and secondary bile acids were studied in a concentration range of 10–9–10–6 mol/l, which corresponds to concentrations found in the plasm of patients with cholestatic jaundice. In general, the bile acid induced a negative inotropic effect which was manifested as a reduction in active tension, maximum rate of tension activation, and maximum rate of tension relaxation. Twitch duration and time to peak tension were unaffected by the bile acids. The negative inotropism was associated with a reduction in ventricular action potential duration. Resting potential, action potential amplitude, and maximum upstroke velocity of phase 0 depolarization were unaffected. Voltage clamp experiments in rat ventricular myocytes demonstrated that sodium taurocholate decreased the slow inward current and slightly increased the outward potassium current. Hence, these effects on the membrane currents are probably responsible for the negative inotropic effect.
Send offprint requests to O. Binah at the above address 相似文献
42.
青年急性冠脉综合征冠脉造特点及随访 总被引:2,自引:0,他引:2
目的:探讨青年急性冠状动脉综合征(ACS)冠状动脉(冠状)造影特点及其与远期心脏事件的关系。方法:比较青年ACS与老年ACS患者冠脉病变程度、范围,并进行心脏事件随访。结果:78例青年ACS患者有冠脉病变74例(94.9%),单支病变46例(58.9%);171例老年ACS患者有冠脉病变166例(97.1%),单支病变41例(23.9%)。平均随访9个月,青年ACS患者发生心脏事件者10例(12.8%),其中心绞痛再入院6例(7.7%);老年ACS患者发生心脏事件者47例(27.5%),其中心绞痛再入院30例(17.5%),两组比较差异有显著性(P<0.05)。结论:ACS患者冠状动脉粥样硬化青年时期之前已经发生,ACS预后与冠脉病变程度和年龄呈正相关。 相似文献
43.
44.
目的观察参附注射液对家兔缺氧型心脏骤停-心肺复苏 (CA- CPR)模型循环恢复的影响.方法 30只家兔随机分为三组,每组 10只;夹闭气管复制缺氧型 CA- CPR模型.预防组 (A组 )夹管前 10min、自主循环恢复后 8、 15min分别静注参附注射液,治疗组 (B组 )自主循环恢复后 8、 15、 22min静注参附注射液,对照组 (C组 )静注生理盐水,时间同 A组;监测夹管前后家兔的心电图、平均动脉压 (PAP)的变化,并记录开始 CPR至自主循环恢复时间和自主呼吸恢复时间、肾上腺素用量、撤呼吸机时间;自主循环维持 4h,并计算 4h存活率.结果三组 CPR成功率、 4h存活率相近;在自主循环恢复时间方面 A组明显快于 C组,在自主呼吸维持时间、肾上腺素用量、撤呼吸机时间方面则两组相近.结论参附注射液可明显缩短家兔缺氧型 CA- CPR模型的自主循环恢复时间,对促进 CA的循环恢复具有积极意义. 相似文献
45.
影响终末期肾衰竭患者心脏扩大的因素 总被引:1,自引:0,他引:1
目的了解成都铁路分局医院血液进化中心终末期肾衰竭并维持性血液透析患者心脏扩大的影响因素,以便提高患者的血液透析质量和生存率。方法回顾本血液净化中心收治的216例终末期肾衰竭并维持性血液透析2月以上患者,根据心脏彩色多普勒检查,分为心脏扩大与心脏未扩大2组,对可能影响心脏扩大的因素:年龄、血液透析病程、每周血液透析时间、高血压、容量超负荷、血红蛋白水平、低蛋白血症等用SPSS10.0软件作Logistic回归分析。结果终末期肾衰竭并维持性血液透析患者216例,心脏扩大者183例,未扩大者33例,心脏扩大的发生率为84.72%。心脏扩大与容量超负荷呈显著正相关,P=0.002,OR值42.619;心脏扩大与高血压呈正相关,P=0.026,OR值15.353;心脏扩大与血红蛋白水平呈负相关,P=0.043,OR值0.934。心脏扩大与年龄、血液透析病程、每周血液透析时间和低蛋白血症无相关关系。结论终未期肾衰竭并维持性血液透析患者心脏扩大发生率高,而容量超负荷、高血压、血红蛋白水平是影响它的关键,高血压及容量超负荷是促进心脏扩大的独立危险因素,血红蛋白水平下降亦是促进心脏扩大的独立危险因素。 相似文献
46.
47.
尽管基因治疗在实验研究方面已做了大量的工作 ,但实际上临床治疗成功的尚不多。现复习这一领域的近期文献 ,并讨论基因治疗的一些限制和潜在的问题 ,强调在心脏外科作基因治疗临床试验之前必须提请考虑的问题和规则。 相似文献
48.
P. Hendrik Pretorius Michael A. King Howard C. Gifford Seth T. Dahlberg Frederick Spencer Ellen Simon Jason Rashkin Naomi Botkin William Berndt Manoj V. Narayanan Jeffrey A. Leppo 《Journal of nuclear cardiology》2005,12(3):284-293
BACKGROUND: Past receiver operating characteristic (ROC) studies have demonstrated that single photon emission computed tomography (SPECT) perfusion imaging by use of iterative reconstruction with combined compensation for attenuation, scatter, and detector response leads to higher area under the ROC curve (A(z)) values for detection of coronary artery disease (CAD) in comparison to the use of filtered backprojection (FBP) with no compensations. A new ROC study was conducted to investigate whether this improvement still holds for iterative reconstruction when observers have available all of the imaging information normally presented to clinical interpreters when reading FBP SPECT perfusion slices. METHODS AND RESULTS: A total of 87 patient studies including 50 patients referred for angiography and 37 patients with a lower than 5% likelihood for CAD were included in the ROC study. The images from the two methods were read by 4 cardiology fellows and 3 attending nuclear cardiologists. Presented for the FBP readings were the short-axis, horizontal long-axis, and vertical long-axis slices for both the stress and rest images; cine images of both the stress and rest projection data; cine images of selected cardiac-gated slices; the CEQUAL-generated stress and rest polar maps; and an indication of patient gender. This was compared with reading solely the iterative reconstructed stress slices with combined compensation for attenuation, scatter, and resolution. With A(z) as the criterion, a 2-way analysis of variance showed a significant improvement in detection accuracy for CAD for the 7 observers (P = .018) for iterative reconstruction with combined compensation (A(z) of 0.895 +/- 0.016) over FBP even with the additional imaging information provided to the observers when scoring the FBP slices (A(z) of 0.869 +/- 0.030). When the groups of 3 attending physicians or 4 cardiology fellows were compared separately, the iterative technique was not statistically significantly better; however, the A(z) for each of the 7 observers individually was larger for iterative reconstruction than for FBP. Compared with results from our previous studies, the additional imaging information did increase the diagnostic accuracy of FBP for CAD but not enough to undo the statistically significantly higher diagnostic accuracy of iterative reconstruction with combined compensation. CONCLUSIONS: We have determined through an ROC investigation that included two classes of observers (experienced attending physicians and cardiology fellows in training) that iterative reconstruction with combined compensation provides statistically significantly better detection accuracy (larger A(z)) for CAD than FBP reconstructions even when the FBP studies were read with all of the extra clinical nuclear imaging information normally available. 相似文献
49.
完全型房室间隔缺损合并法洛四联症心内矫正术 总被引:2,自引:2,他引:0
目的总结心内矫正术治疗完全型房室间隔缺损合并法洛四联症(CAVSD-TOF)的经验. 方法从1985年1月至2002年5月,共行CAVSD-TOF心内矫正术12例,年龄6~16岁(11.1±2.8岁),采用右心房、右心室纵切口,前7例采用三片法补片,后5例用二片法补片修补房室间隔缺损,左侧房室瓣裂隙采用间断缝合,右心室流出道用跨瓣补片加宽. 结果术后早期死亡4例,前7例死亡3例,后5例死亡1例,死亡原因为严重低心排血量3例,灌注肺1例.长期随访6例,随访时间3个月至13.5年,无任何症状,NYHA心功能Ⅰ级或Ⅱ级. 结论 CAVSD-TOF采用右心房、右心室纵切口,二片法补片修补房室间隔缺损,常规间断缝合左侧房室瓣裂隙,跨瓣补片加宽右心室流出道能取得较良好的效果. 相似文献
50.
Objective Reduction ascending aortoplasty is an alternative procdure to the replacement of the ascending aorts in case of ascending aorta dilation. However,its applicabikity is still under debate.This retrospective study was designed to evaluuate the midterm follow-up of unsupported ascending reduction aortoplasty for of the ascending aorta in petients with aortic valve dis- ease.Methods From October ,1996 to April,2007, a total of 54 patients with aortic valve disease and dilatation of the ascending aorta underwent unsupported reduction aortoplasty in combination with aortic valve replacement at our institution The diameter of the ascending aorta was measyred before and early after sugery and then later between 13 and 96 menths [mean (23 ±16)months] posto- perativeiy using echocardiography.Results Two patients were dead with thean overall perioperative mortality rate was of 3.7%. The reduction aortoplasty decreased the diameter of the aorta from (45.77±6.02) mm p~eope~afive]y to (34.67 ~4.81) mm early after surgery (P<0.01). During follow-up, the diameter d aorta increased from (34.67±4.81) mm early after surgery to (37.65± 6.35) mm after a mean follow-up of (23±16) months (P<0.01), including the diameters are greater than > 45 mm within 5 pa- tients. Aortic stenosis and an early postoperative diameter greater than 40 mm m'e independent risk factors for redilatation. Conchusion Because of the unsatisfied midterm follow-up redilation of unsupported reduction aortoplasty for dilation of the ascending aorta with aortic valve disease, this group of patients needs continued intimate fallow-up or even reoperation. The patients of stenosis is the surtable indication for RAA, and it is necessary to reduce the diameter of aorta to be lees than 40 mm to prevent redilation. 相似文献