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71.
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   
72.
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   
73.
本文对高血压病病人及对照的生活习惯、个人嗜好、精神因素等15个因素进行了1:1配比病例对照研究及 Logistic 回归分析,同时调查厂遗传因素和高血压病的关系。结果表明:超体重、发病前二年受应激事件刺激、母亲高血压史为高血压病的危险因素。高血压病遗传度35.58%,提示遗传因素在该病的发生过程中不起主要作用。  相似文献   
74.
75.
Purpose To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic stents. Methods Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35–72 years, mean 54 years) underwent the TIPS procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies, wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n=48) and self-expanding (n=45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range 3–24 months) were obtained in 39 of these patients. Results Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy, the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n=1) and late shortening (n=4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up (mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant complications related to the TIPS insertions. Conclusion An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding stent.  相似文献   
76.
本文用X线电影摄影方法评价了49例左室舒张(充盈)功能的影响因素。冠心病(CAD)组23例,高血压病组12例,正常对照组14例。左室充盈功能或顺应性主要受冠脉病变严重程度的影响。冠脉狭窄程度越重,并有陈旧性心肌梗塞、室壁运动异常、EF下降,则充盈功能受损愈明显。血压、年龄因素对舒张充盈功能的影响较小。在CAD组中,心率与1/3充盈分数呈负相关,与正常化高峰充盈率(NPFR)不相关,而EF则与NPFR相关良好。  相似文献   
77.
The results of systemic autonomic nerve function studies in patients with closed-angle glaucoma and ocular hypertension are reviewed. Autonomic neuropathy has been demonstrated in 58% of patients with closed-angle glaucoma and 42% of ocular hypertensive subjects, with significantly increased prevalence in ocular hypertensives with narrow iridocorneal angles. The implications are discussed, with particular reference to the pathogenesis of raised intraocular pressure.  相似文献   
78.
赖诺普利与依那普利对高血压的疗效比较   总被引:1,自引:1,他引:0  
92例原发性Ⅰ和Ⅱ期高血压病人采用随机、单盲方法,分2组治疗。一组用赖诺普利,po,20-80mg/d,另一组用依那普利,po,10-40mg/d,疗程均为4wk。降压总有效率和降压幅度:赖诺普利是89%和2.9/2.0kPa,依那普利是97%和3.1/2.1kPa,2药降压均显著(P<0.01),降压疗效相仿(P>0.05)。不良反应发生率是29%和34%,其中最多是干咳。结果提示赖诺普利治疗轻、中度高血压有效、安全。  相似文献   
79.
松龄血脉康抑制肺动脉高压的实验研究   总被引:1,自引:0,他引:1  
为观察松龄血脉康胶囊对肺动脉高压大鼠肺动脉压的影响,取100只健康Wistar大鼠,其中60只背部注射野百合碱monocrotaline,MCT80mg/kg复制出肺动脉高压模型。再将其分为两组,各30只,其中一组以标准饲料喂养,另一组加用松龄血脉康胶囊1.5g·kg-1·d-1。其余40只健康大鼠做为正常对照组,在实验当天、7天、14天、21天、28天、35天从各组中随机抽取5只行右心导管测肺动脉压。结果:注射MCT后肺高压组28天时达高峰,但加用松龄血脉康组上升幅度明显小于未用药组。结论:松龄血脉康有显著抑制大鼠肺动脉高压发展的作用  相似文献   
80.
8kg以下婴儿室间隔缺损伴肺动脉高压手术治疗   总被引:25,自引:0,他引:25  
为提高小婴儿室缺伴肺动脉高压的手术疗效,总结16例8kg以下室间隔缺损(室缺)伴肺动脉高压婴儿行急诊手术修补室缺的经验。其中14例在深低温停循环下进行,手术效果满意;术后死亡1例(6%)。作者认为,婴儿巨型室缺应尽早手术治疗为宜,深低温停循环方法尤为适合;术后强调持续保持病婴镇静及呼吸道通畅,防止肺高压危象的发生。  相似文献   
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