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51.
Captopril was given to 15 unselected patients with essential hypertension (WHO II) at a dose range of 300 to 600 mg/day. Hemodynamic indexes (thermodilution) as well as levels of plasma norepinephrine, epinephrine, renin activity and aldosterone were determined simultaneously at the end of 2 weeks of placebo and after 8 weeks of captopril treatment. Systolic and diastolic arterial pressures were reduced significantly by treatment both supine (p less than 0.0025) and standing (p less than 0.0025). The diastolic arterial pressure was normalized (less than 95 mm Hg) in five patients and significantly reduced in four, whereas six patients were considered poor responders (mean arterial pressure decrease 10 mm Hg or less). The decrease in arterial pressure correlated significantly with the reduction in total peripheral resistance (r = 0.71), whereas cardiac index did not change and stroke index increased because of a slight decrease of heart rate. Plasma and urinary norepinephrine and epinephrine did not change during treatment. Moreover, the response of both heart rate and plasma catecholamines to upright posture was not altered by captopril treatment. Plasma renin activity increased and plasma aldosterone concentration decreased during treatment. These results suggest that inhibition of converting enzyme activity by captopril induces a reduction in arterial pressure through a reduction in total peripheral resistance. There was no evidence of an appreciable reduction in sympathetic nervous system activity during therapy.  相似文献   
52.
To test whether highly anaplastic myeloma and immunoblastic lymphoma are truly identical disease processes, simultaneous series were compared in respect to cytomorphologic features, immunoglobulin content or secretion, clinical and laboratory findings, and patient survival. Although the series partially overlapped in each studied feature, different trends served to distinguish them. Of the 14 patients with myeloma, all were dead at two years, whereas six of the 22 patients with lymphoma were disease-free at 35 to 78 months. Only 50 percent of patients with myeloma received intensive chemotherapy, whereas all 19 patients with stage III or IV lymphoma received such therapy. Myelomas secreted predominantly IgA heavy chain rather than IgG and lambda light chain rather than kappa. Lymphomas contained predominantly IgM rather than IgG and kappa rather than lambda. There were no IgM myelomas and no IgA lymphomas. The shorter survival of patients with the extremely anaplastic form of myeloma, as compared with patients who had immunoblastic lymphoma, may relate, in part, to prior therapy for previous lower grade myeloma; however, intrinsic differences in the nature of these two disease processes are reflected in their disparate immunologic characteristics.  相似文献   
53.

Introduction

A new drug with prognostic impact on heart failure, sacubitril/valsartan, has been introduced in current guidelines. However, randomized trial results can be compromised by lack of representativeness. We aimed to assess the representativeness of the PARADIGM-HF trial in a real-world population of patients with heart failure.

Methods

We reviewed the records of 196 outpatients followed in a heart failure clinic between January 2013 and December 2014. After exclusion of 44 patients with preserved ejection fraction, the inclusion and exclusion criteria of the trial were applied.

Results

Of the 152 patients with systolic heart failure, 106 lacked one or more inclusion criteria and 45 had at least one exclusion criterion. Considering only patients with ejection fraction ≤35% (HFrEF) (n=88), 43 patients lacked at least one inclusion criterion and 25 patients had at least one exclusion criterion. Combining the inclusion and exclusion criteria, 24.3% of patients with systolic HF (ejection fraction ≤50%) and 42% of patients with HFrEF would be eligible for the PARADIGM-HF trial.

Conclusion

One in four patients with systolic HF followed in a heart failure outpatient clinic would fulfill the reference study criteria for treatment with the new drug, sacubitril/valsartan.  相似文献   
54.
The course and management of 40 consecutive newborns (aged less than 2 weeks) who presented with signs and symptoms of congenital heart disease were reviewed to determine the impact of 2-dimensional (2-D) echocardiography on their subsequent management. Of the 40 patients with congenital heart disease, 60% did not undergo cardiac catheterization. Forty-two percent of the patients who were treated surgically went directly to operation without preoperative cardiac catheterization. Only 40% of the patients with congenital heart disease required cardiac catheterization in the newborn period, and 43% of these procedures were primarily therapeutic (that is, balloon atrial septostomy). In each patient 2-D echocardiography correctly identified the major cardiac malformation and there was good agreement with angiographic, surgical, and autopsy findings. The most commonly overlooked defect was a patent ductus arteriosus. Thus, 2-D echocardiography not only allows diagnosis of congenital heart disease in the newborn but can expedite clinical management. No longer is cardiac catheterization necessarily the primary means for an anatomic diagnosis of congenital cardiac malformations in the newborn.  相似文献   
55.
儿童过敏性紫癜901例临床分析   总被引:1,自引:1,他引:1  
目的 探讨近年来儿童过敏性紫癜(HSP)患病率和临床表现特点的变化.方法 回顾性分析我院儿科1995年1月至2005年12月住院的901例过敏性紫癜患儿的临床资料.结果 ①1995-2005年每年HSP住院构成比依次为23/2165(1.06%)、29/2098(1.38%)、24/1973(1.22%)、39/2008(1.94%)、54/2433(2.22%)、86/2611(3.29%)、94/2724(3.45%)、99/3014(3.28%)、138/2900(4.76%)、143/3177(4.50%)、172/3500(4.91%),呈逐年明显增高趋势;②48.6%的患儿有前驱感染史,4个家庭分别有2~3个亲属先后患本病.③部分患儿非典型起病,165例(18.31%)起病时皮肤无紫癜,其中90例以消化道症状起病,63例以关节症状起病,6例以肾受累症状起病,1例中枢神经症状起病,5例其他症状起病;14例以消化道症状起病的HSP患儿经胃镜检查呈胃、十二指肠黏膜小血管炎表现而于皮肤紫癜出现前拟诊.④95例(10.5%)有皮肤、关节、消化道、肾脏以外的系统受累,其中中枢神经系统受累30例,男性生殖器受累11例,胰腺受累3例,心脏受累47例,1例肺出血.结论 HSP患病率近年来有明显升高趋势.其家族集聚发病、不典型起病表现及多系统损害尤其是脑、肺、胰腺、心脏等重要脏器的受累值得重视.胃肠镜检查可助消化道症状起病的非典型HSP的早期诊断.  相似文献   
56.
线粒体DNA损伤与细胞凋亡   总被引:1,自引:0,他引:1  
细胞核DNA(nuclear DNA,nDNA)损伤后诱导细胞凋亡的信号转导途径已经逐渐清晰,而线粒体DNA(mitochondrial DNA,mtDNA)损伤与细胞凋亡之间的关系尚有待进一步明确.目前已有研究结果表明:mtDNA断裂、缺失或功能缺陷能够显著影响细胞凋亡发生率;线粒体缺失细胞(p0细胞)同其亲代细胞相比,对多种凋亡诱导因素的反应存在显著差异;ROS的产生并非mtDNA损伤诱导凋亡的必要条件,mtDNA损伤断裂本身可能启动了凋亡的级联反应.但mtDNA的损伤,在细胞凋亡的信号转导途径具体扮演何种角色,还有待深入研究.  相似文献   
57.
Background The monocrotaline (MCT)-induced pulmonary arterial hypertension model is one of the most reproduced today, presenting as a limitation the absence of plexiform lesions, typical manifestations of the severe disease in humans.Objective To evaluate the severity of MCT-induced pulmonary arteriopathy by pathological findings of lung and heart tissue samples, clinical course and 37-day survival.Methods Fifty male Wistar rats were divided into one of the four groups – control (CG) (n = 10) and three intervention (MCT) groups. The MCT groups received intraperitoneal injection (60 mg/kg) of MCT and remained exposed to the substance for 15 days (G15, n = 10), 30 days (G30, n = 10) and 37 days (G37, n = 20). At the end of each period, the animals were sacrificed, and pulmonary and cardiac tissues were collected for anatomopathological and morphometric analysis. The Kruskal-Wallis test was used, considering a level of significance of 5%.Results In the lungs of MCT animals, lesions related to pulmonary arteriopathy were found, including muscularization of the arterioles, hypertrophy of the middle layer and concentric neointimal lesions. Complex lesions were observed in MCT groups, described as plexiform and plexiform-like lesions. Right ventricular hypertrophy was evidenced by increased thickness and diameter of the cardiomyocytes and a significant increase in the right ventricular wall thickness (p <0.0000).Conclusion The MCT model was able to generate moderate-severe pulmonary arteriopathy associated with secondary right ventricular hypertrophy. The 37-day survival rate was 50%. To our knowledge, this study was the first to note the presence of complex vascular lesions, similar to those observed in patients with severe pulmonary arterial hypertension, in an isolated MCT model. (Arq Bras Cardiol. 2020; 115(3):480-490)  相似文献   
58.
Background Differences between the updated versions of the Brazilian Guideline on Dyslipidemias and the American Heart Association (AHA)/American College of Cardiology (ACC) Cholesterol Guideline regarding cardiovascular risk stratification and statin eligibility are unknown.Objectives To compare cardiovascular risk categorization and statin eligibility based on the Brazilian guideline with those based on the AHA/ACC guideline in primary prevention patients.Methods We retrospectively analyzed individuals aged 40-74 years without high-risk conditions, with LDL-c 70 to < 190 mg/dL, not on lipid-lowering drugs, who underwent routine clinical assessment. Cardiovascular risk was stratified according to the Brazilian and the AHA/ACC guidelines. Subjects were considered eligible for statin therapy if LDL-c was at least 30 mg/dL above the target for the cardiovascular risk (Brazilian guideline) or the 10-year atherosclerotic cardiovascular disease risk was ≥7.5% (AHA/ACC guideline). A p-value < 0.05 was considered statistically significant.Results The study sample consisted of 18,525 subjects (69% male, age 48 ± 6 years). Among subjects considered at intermediate or high risk by the Brazilian guideline, over 80% would be in a lower risk category by the AHA/ACC guideline. Among men, 45% and 16% would be statin eligible by the Brazilian and the AHA/ACC guidelines criteria, respectively (p < 0.001). Among women, the respective proportions would be 16% and 1% (p < 0.001). Eighty-two percent of women and 57% of men eligible for statins based on the Brazilian guideline criterion would not be eligible according to the AHA/ACC guideline criterion.Conclusions Compared with the AHA/ACC guideline, the Brazilian guideline classifies a larger proportion of primary prevention patients into higher-risk categories and substantially increases statin eligibility. (Arq Bras Cardiol. 2020; 115(3):440-449)  相似文献   
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