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To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.  相似文献   
23.
尼莫地平联合卡维地洛治疗原发性高血压78例临床分析   总被引:1,自引:0,他引:1  
目的分析尼莫地平联合卡维地洛治疗原发性高血压的临床疗效。方法将150例原发性高血压随机分成两组,对照组给予尼莫地平治疗,治疗组在对照组治疗的基础上,加之卡维地洛。结果治疗组与对照组显效率分别为33.3%和26.4%,总有效率为88.5%和76.4%,两组相比具有显著性差异(P〈0.05)。结论尼莫地平联合卡维地洛治疗原发性高血压疗效更为显著。  相似文献   
24.
孙宁玲 《世界临床药物》2009,30(10):577-580
高血压高危患者的降压治疗既需降低血压,又需保持足够血流以保障器官灌注。血压降低过度无疑也有一定风险,因此控制皿压需要底线。高危高血压患者的个体差异大,在降压治疗过程中,临床医生既要以循证医学为鉴,叉须遵循个体化治疗原则,把握好降压幅度和速度,坚持高质量平稳降压,才能更好地保护靶器官,减少心脑血管意外的发生。  相似文献   
25.
HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white matter hyperintensities. METHODS: In the Leukoaraiosis And DISability in the elderly (LADIS) study, we investigated the relationships between DM, hypertension, blood pressure and MTA in 582 subjects, stratified by white matter hyperintensity severity, using multinomial logistic regression. MTA was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95% CI: 1.1-7.8) compared with an MTA score of 0 (no atrophy). The odds ratio for MTA score 2 was not significantly increased (OR 1.8; CI: 0.9-4). Systolic and diastolic blood pressure and a history of hypertension were not associated with MTA. There was no interaction between DM and hypertension. Stratification on white matter hyperintensities (WMH) did not alter the associations. CONCLUSION: Our study strengthens the observation that MTA is associated with DM, independently of the amount of small vessel disease as reflected by WMH.  相似文献   
26.
目的: 几乎没有研究报道妊娠高血压综合征 (妊高征 ) 患者尿蛋白对新生儿出生体重的影响, 该研究欲探讨妊高征患者不同水平尿蛋白对新生儿出生体重的影响关系。方法: 1997年 1月 ~2004年 6月期间, 住院分娩患中、重度妊高征产妇 136例, 对新生儿出生体重与各种因素进行回归分析及t检验分析。结果: 单变量回归分析尿蛋白、孕龄分别与新生儿出生体重有高度显著性关系 (P<0. 01); 尿蛋白和孕龄一起进入多元回归分析, 校正影响因素, 尿蛋白和孕龄仍然是影响新生儿出生体重显著性因素 (P<0 .01); 与妊高征尿蛋白 ( +) 比较, 尿蛋白 无显著性影响新生儿出生体重 (P>0. 05), 尿蛋白 有显著性影响新生儿出生体重 (P<0. 01)。结论: 新生儿出生体重与妊高征患者尿蛋白丢失有关, 尿蛋白 丢失将严重影响新生儿出生体重。  相似文献   
27.
目的探讨自发性高血压大鼠颈动脉中抑癌基因P53和原癌基因c-jun、c-fos、c-myc mRNA的表达.方法用逆转录聚合酶链式反应检测两种基因的表达水平.正常雄性大鼠作为对照组.结果 SHR颈动脉中,抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,较WKY差异有显著性(P<0.05).结论自发性高血压大鼠颈动脉组织中抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,癌基因的活化可能与自发性高血压大鼠颈动脉血管重构有关.  相似文献   
28.
茶色素对冠心病及高血压病病人血小板功能的影响   总被引:1,自引:0,他引:1  
目的:探索茶色素对冠心病、高血压病病人血小板功能的影响。方法:冠心病病人36例(男性21例,女性15例;年龄64±s4a);高血压病病人30例(男性18例,女性12例;年龄58±8a)。采用茶色素250mg,po,tid,30d为一个疗程。结果:治疗后TXB2下降,6-keto-PGP1α上升,TXB2/6-keto-PGF1α比值下降(P<0.01或P<0.05),GMP-140下降(P<0.05),PagT,PadT下降(P<0.05)。结论:茶色素具有降低血小板表面活性作用,抑制血小板聚集和粘附,抗血栓形成,改善微循环,对冠心病和高血压病病人起到积极的防治作用。  相似文献   
29.
1. Plasma potassium and chloride concentrations were raised and plasma renin activity, aldosterone, bicarbonate and arterial pH were reduced in two brothers with the syndrome of hypertension and hyperkalaemia with normal glomerular filtration rate (Gordon's syndrome), on unrestricted or moderately restricted sodium diets. 2. These abnormalities were corrected in both patients within 10 days of severe sodium restriction. 3. Pressor sensitivity to cold and angiotensin II decreased on low sodium diet, associated with a fall in blood pressure. 4. Increasing distal tubular sodium delivery by infusion of normal saline increased fractional excretion of potassium when aldosterone had been stimulated by severely restricted sodium diet, but not when aldosterone levels were low on unrestricted sodium diet. 5. These findings are consistent with excessive sodium reabsorption as the primary renal lesion in Gordon's syndrome, leading to volume expansion and suppression of renin and aldosterone. Severe dietary sodium restriction leading to volume contraction, by stimulating renin and aldosterone and promoting kaliuresis, corrects the abnormalities.  相似文献   
30.
A randomized, double-blind, placebo-controlled study was conducted to study the effects of acute and chronic administration of carvedilol in essential hypertension, with special emphasis on renal haemodynamics and function. Acute administration of a single dose of 50 mg carvedilol reduced systolic and diastolic blood pressure without inducing reflex tachycardia. Renal blood flow was preserved; accordingly, renal vascular resistance was significantly reduced. A significant reduction in the glomerular filtration rate and filtration fraction was observed. Plasma renin activity (PRA) and plasma aldosterone values were not changed. Chronic carvedilol treatment produced a significant fall in systolic and diastolic blood pressure, heart rate, PRA and plasma aldosterone. Renal blood flow, glomerular filtration rate and filtration fraction also remained unchanged; renal vascular resistance decreased significantly. It is concluded that carvedilol possesses definite antihypertensive and renal vasodilating properties, both acutely and after chronic treatment.  相似文献   
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