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991.
目的研究静脉注射尼卡地平对重度高血压患者血压和左心功能的影响。方法用尼卡地平持续24h静脉滴注(1.5~3mg/h)治疗20例重度高血压患者,观察给药前后血压、心率、左心功能以及自觉症状变化。结果降压显效率100%,5min起效,0.5~1h血压降至理想水平,同时全部病例脑循环障碍症状消失,24h降压效果平稳,心率轻度增快(<10min-1),左心收缩功能明显改善,而舒张功能未见变化。结论静脉注射尼卡地平可迅速、显著而平稳降低重度高血压患者的血压,改善左心收缩功能。  相似文献   
992.
目的探讨心钠素(ANP)在高血压发病中的作用。方法52例原发性高血压(EH)患者,随机分组,应用硝苯地平或卡托普利治疗2周前后,测定血浆、唾液、尿液ANP含量的变化,并与健康组对照。结果治疗前患者血浆、唾液、尿液中ANP均高于对照组(P<0.01)。治疗2周后,高血压组SBP、DBP和血、唾液、尿液中ANP较治疗前明显降低(P<0.01),而治疗组间比较差异无显著性(P>0.05),且唾液和尿液中ANP与血浆中浓度有同样变化趋势。结论硝苯地平和卡托普利可能是通过抑制ANP的产生和释放的某个环节而发挥其降压效果的。  相似文献   
993.
Beta-blockers and diabetes: the bad guys come good   总被引:5,自引:0,他引:5  
Type 2 diabetes is becoming very common and is closely linked to physical inactivity and obesity. It is associated with clustering of coronary risk factors and 60–80% of cases have hypertension.The first therapeutic action is appropriate adjustment of life style. Anti-hypertensive therapies such as diuretics, ACE inhibitors and calcium antagonists have been effective in reducing cardiovascular events in type 2 diabetes, though calcium antagonists may be less effective than older therapies and ACE-inhibitors in reducing the risk of heart attacks and heart failure (but possibly more effective in stroke reduction).Beta-blockers (BBs) have a poor image as a potential therapy due to apparent adverse effects on surrogate end-points such as insulin-resistance. However large, controlled trials have shown BBs to be highly effective in reducing the risk of cardiovascular events and death in post myocardial infarction patients with diabetes. The UKPDS study in type 2 diabetics with hypertension showed first-line beta-blockade to be at least as effective as ACE-inhibition in preventing all primary macrovascular and microvascular end-points. The active ingredient appears to be beta-1 blockade, acting not only to lower blood pressure but also to prevent sudden death and cardiovascular damage stemming from chronic beta-1 stimulation associated with raised noradrenaline activity.By contrast, in the LIFE study atenolol was less effective than the angiotensin receptor antagonist losartan in reducing cardiovascular events and all-cause mortality in mainly elderly hypertensives with diabetes. Thus the best beta-blocker results in reducing hard cardiovascular end-points occur in hypertension studies (including the UKPDS study) involving younger/middle aged (say less than 60–65 years) patients, with relatively high sympathetic activity, relatively compliant/elastic arteries (narrow pulse-pressure) and normally functioning beta-1 receptors. In elderly hypertensive patients beta-blockers may be given as second-line therapy on the back of a low-dose diuretic (but possibly as first line agent in elderly hypertensives with prior myocardial infarction).Thus inappropriate attention to surrogate end-points can lead to faulty prescribing habits. Beta-blockers, currently severely underprescribed, should be considered as a first line therapeutic option for all diabetics with ischaemic heart disease or younger/middle aged diabetics with hypertension (but co-prescribed with low dose diuretic therapy in the elderly). The active ingredient for cardiovascular protection appears to be beta-1 blockade; optimal efficacy in lowering blood pressure and safety e.g. reducing risk of bronchoconstriction, is achieved by choosing an agent with high beta-1 selectivity.  相似文献   
994.
Summary The aim of this study was to determine the value of von Willebrand factor (vWF), a well-characterized endothelial cell protein secretion, as a marker for prognosis in patients with primary pulmonary hypertension (PPH). Venous and arterial blood samples were obtained from 18 clinically diagnosed PPH patients and 12 case controls matched for age and sex. Plasma vWF antigen was determined by enzymelinked immunosorbent assay (ELISA). The patients' multimeric vWF pattern was analyzed by sodium dodecylsulfate (SDS)-agarose-acrylamide electrophoresis, Western blot, and densitometric analysis. vWF sialic acid content was determined by a lectin-based ELISA. The PPH patients showed a higher content of vWF antigen in venous (P = 0.0026) and arterial (P = 0.0094) blood samples than controls. The mean vWF sialic acid content of the PPH patients corresponded to 37.7% of the mean value for the control group. On the basis of the hemodynamic response to vasodilator trial, the PPH patients were grouped as responders or nonresponders. The latter group showed a significantly higher plasma vWF antigen antecubital vein/radial artery ratio, an increased number of unusually large vWF multimers, and a diminished content of vWF sialic acid in comparison with the first group. We believe that our results establish the nature of vWF alterations that are related to endothelial cell damage in patients with primary pulmonary hypertension and that this could be of value when establishing the prognosis in this group of patients.  相似文献   
995.
目的 了解不同经济水平农村居民高血压危险因素有无不同.方法 采用自编问卷对河北省冀州市不同经济水平的≥35岁的农村居民中的469名新发高血压患者和2799名对照进行了原发性高血压危险因素调查,并进行了多因素Logistic回归分析.结果 经济水平较好组高血压危险因素(以OR值大小为序)依次为家族史、体质量指数、盐腌食品、每天吃鸡蛋、年龄,它们的OR分别为2.863、1.286、1.263、1.200、1.052;经济水平较差组高血压危险因素(以OR值大小为序)依次为家族史、吸烟、每天吃鸡蛋、饮酒、文化程度、性别、喜吃肥肉、体质量指数、年龄,它们的OR分别为3.990、1.767、 1.753、1.728、1.532、1.448、 1.276、 1.205、1.068,每天吃新鲜水果和家庭年人均收入高是高血压的保护因素,它们的OR为0.708和0.788.结论 经济水平不同高血压危险因素不完全相同.  相似文献   
996.
OBJECTIVES: LDL-cholesterol particles from hypertensive patients exhibit enhanced susceptibility to in vitro oxidation, an abnormality thought to increase cardiovascular risk. We tested whether blood pressure (BP) normalization can reverse this abnormality. DESIGN: Double-blind, randomized pharmacological intervention trial. SETTING: Clinical research centre. Subjects. A total of 29 nondiabetic, normolipidaemic patients with essential hypertension (BP= 151 +/- 3/99 +/- 1 mmHg) and 11 normotensive controls (BP=125 +/- 3/85 +/- 1 mmHg) matched for gender, age, obesity, glucose tolerance and lipid profile. Intervention. Anti-hypertensive treatment for 3 months with a calcium-antagonist in randomized combination with either an ACE inhibitor or a beta-blocker. MAIN OUTCOME MEASURES: Lag phase of copper-induced LDL oxidation, cell-mediated (human umbilical vein endothelium) generation of malondialdehyde (MDA) by LDL and vitamin E content in LDL. RESULTS: At baseline in hypertensives versus controls, lag phase was shorter (89 +/- 3 vs. 107 +/- 6 min, P < 0.04), MDA generation was higher (5.8 +/- 0.1 vs. 5.1 +/- 0.2 nmol L(-1), P=0.002), and vitamin E was reduced (6.40 +/- 0.05 vs. 6.67 +/- 0.11 microg mg(-1), P=0.03). At 3 months, BP was normalized (124 +/- 3/81 +/- 1, P < 0.0001 vs. baseline, P=ns versus controls), lag phase was prolonged (to 98 +/- 3 min, P=0.0005), MDA generation was reduced (5.6 +/- 0.1 nmol L-1, P = 0.001), and vitamin E was increased (6.53 +/- 0.05 microg mg(-1), P=0.003), with no significant differences between the randomized groups. CONCLUSIONS: In nondiabetic, nonobese, normolipidaemic patients with essential hypertension, LDL susceptibility to copper- and cell-mediated oxidation is increased. BP normalization is associated with a significant improvement, but not a full reversal, of this abnormality.  相似文献   
997.
OBJECTIVE  Evaluate the effectiveness of collaborative management of hypertension by primary care-pharmacist teams in community-based clinics. STUDY DESIGN  A 12-month prospective, single-blind, randomized, controlled trial in the Providence Primary Care Research Network of patients with hypertension and uncontrolled blood pressure. METHODS  As compared to usual primary care, intervention consisted of pharmacy practitioners participating in the active management of hypertension in the primary care office according to established collaborative treatment protocols. At baseline, there was no significant difference in blood pressure between groups. Primary outcome measures were the differences in mean systolic and diastolic blood pressures between arms at study end. Secondary measures included blood pressure goal attainment (<140/90 mmHg), hypertension-related knowledge, medication adherence, home blood pressure monitoring, resource utilization, quality of life, and satisfaction. RESULTS  A total of 463 subjects were enrolled (n = 233 control, n = 230 intervention). Subjects receiving the intervention achieved significantly lower systolic (p = 0.007) and diastolic (p = 0.002) blood pressures compared to control (137/75 mmHg vs. 143/78 mmHg). In addition, 62% of intervention subjects achieved target blood pressure compared to 44% of control subjects (p = 0.003). The intervention group received more total office visits (7.2 vs. 4.9, p < 0.0001), however had fewer physician visits (3.2 vs. 4.7, p < 0.0001) compared to control. Intervention subjects were prescribed more antihypertensive medications (2.7 vs. 2.4, p = 0.02), but did not take more antihypertensive pills per day (2.4 vs. 2.5, p = 0.87). There were minimal differences between groups in hypertension-related knowledge, medication adherence, quality of life, or satisfaction. CONCLUSIONS  Patients randomized to collaborative primary care-pharmacist hypertension management achieved significantly better blood pressure control compared to usual care with no difference in quality of life or satisfaction. The primary author had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.  相似文献   
998.
目的探讨抗氧化剂PZ51对卒中易感型自发性高血压大鼠(SHRsp)高血压发展的慢性过程中的脑保护作用。方法22只SHRsp大鼠随机分为PZ51组和对照组,每组各11只,灌胃治疗6周。用分光光度计测大脑皮质匀浆丙二醛(MDA)、一氧化氮(NO)浓度;Westernblot检测大脑皮质内皮型一氧化氮合酶(eNOS)、神经元型一氧化氮合酶(nNOS)和诱导型一氧化氮合酶(iNOS)的蛋白表达;光镜检测颈动脉内膜中层厚度(IMT)。结果与对照组比较,PZ51组显著降低了大脑皮质匀浆MDA浓度[(2.09±0.62)nmolmg蛋白vs(4.11±0.45)nmolmg蛋白,P<0.001]和NO浓度[(0.82±0.19)μmolmg蛋白vs(1.24±0.28)μmolmg蛋白,P<0.001];PZ51抑制大脑皮质iNOS蛋白表达(P<0.01),对eNOS和nNOS无影响;光镜检查示PZ51组颈动脉IMT显著降低。结论PZ51显著降低了SHRsp大脑皮质MDA和NO浓度;抑制iNOS蛋白表达;降低了颈动脉IMT,从而发挥对SHRsp的脑保护作用。  相似文献   
999.
高血压及抗高血压药物对勃起功能的影响与研究进展   总被引:2,自引:0,他引:2  
高血压与抗高血压药物均与血管性勃起功能障碍的发病有密切关系,现就其相互影响及机制作一综述,并对高血压合并勃起功能障碍的防治对策作一简单介绍。  相似文献   
1000.
BACKGROUND: Portal hypertension is a common disease and its major surgical therapeutic approaches include devascularization and shunting. This study was undertaken to investigate the effects of combined splenocaval or mesocaval C shunt and portoazygous devascularization (combined procedures) on portal hypertension. METHODS: The clinical data of 150 patients with portal hypertension who had undergone combined procedures at the First Affiliated Hospital of Zhengzhou University from May1990 to May 2003 were analyzed retrospectively. RESULTS: The mean free portal pressure (FPP) was 25.6±1.83 mmHg, 18.0±2.07 mmHg and 18.4±2.19 mmHg before operation, after splenectomy plus splenocaval or mesocaval C shunt, and combined procedures, respectively. There was no operative death in all patients. The 1-7 year follow-up of 100 patients showed rebleeding in 3 patients, encephalopathy in 4, thrombosis of artificial vascular graft in 3, and dying from liver failure in 2. CONCLUSIONS: The combined procedures can not only decrease portal pressure but also preserve hepatic blood flow to some extent. It may be one of the best choices for treating portal hypertension in China.  相似文献   
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