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51.
(席思川)(车东媛)(张婉蓉)TheInhibitoryEffectofRadixSalviaeMiltiorrhizaeonHypoxicStructuralRemodelingofIntra-acinarPulmonaryArteries¥XISi-c...  相似文献   
52.
Pattern electroretinograms (PERGs) in response to 8.3 Hz alternating gratings (16.6 rev/sec) of different spatial frequencies were recorded in normal subjects as well as in patients affected by early glaucoma and ocular hypertension. In normal subjects the PERG response is spatially tuned, with a maximum at about 1.5 cycles/deg and attenuation at higher and lower spatial frequencies. In all cases of early glaucoma and in the great majority of cases of ocular hypertension the PERG was reduced, as compared with that of normal subjects, mainly in the medium range of spatial frequencies (at which the PERG has its maximal amplitude).  相似文献   
53.
本文报告等容血液稀释(简称DH)治疗高血压病75例,总有效率为90.2%,48例随访2年血压下降稳定持久,血液流变学改善,总有效率为87.5%。结果表明:HD治疗高血压病可以改善血流高粘滞状态,降低血液粘度,增强血液流动性,减少血流阻力,改善微循环灌流,从而达到降低血压和改善器官血流,达到持久降压及减少器官合并症。一次HD与降压药适量配伍,疗效更显著而持久,可维持数月至2年以上。  相似文献   
54.
近年来的研究结果发现由Th1/Th2细胞分泌的淋巴因子与妊娠高血压综合征联系密切 ,可能参与了其病因及病理生理过程 ,对它的深入研究有利于妊娠高血压综合征诊断、治疗水平的提高  相似文献   
55.
原发性高血压患者425例(男252,女173;年龄60±s12a)采用美托洛尔100mg,po,每晨1次,4wk为一个疗程。总有效率82.4%,治疗2wk后血压继续下降,心率并不继续减慢。不良反应主要为心率减慢后的症状及神经系症状,停药率6.4%。60a以上的患者总有效率及停药率与中、青年患者无明显区别。故美托洛尔同样适用于老年人。  相似文献   
56.
57.
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation.  相似文献   
58.
59.
Effects of hepatoportal osmo-receptive (or sodium-receptive) afferents on neurons within the dorsal motor nucleus of the vagus (DMV) were investigated electrophysiologically in urethane-chloralose anesthetized rats. Responses of 56 spontaneously active neurons to antidromic stimulation of the ventral trunk of the subdiaphragmatic vagus were recorded in the left DMV. Among them, 35 neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve (inhibitory neurons), except two neurons that were slightly excited. Effects of portal infusion of 3.6% NaCl were examined on 26 inhibitory neurons. Sixteen neurons increased their discharge rates and one neuron decreased its discharge rate in response to portal infusion of hypertonic saline. Thirty-five DMV neurons responded to electrical stimulation of the dorsal trunk of the subdiaphragmatic vagus were inhibited by electrical stimulation of the hepatic branch of the vagus. Four neurons were excited by this stimulation. Relatively smaller number of neurons (5 out of 22 inhibitory neurons) increased their discharge rates in response to portal infusion of hypertonic saline. In conclusion, the response of DMV neuron observed in this experiment was characterized by increasing the frequency of spike discharges in response to portal infusion of hypertonic saline. However, these neurons were inhibited by electrical stimulation of the hepatic branch of the vagus nerve. These results suggest that the hepatoportal osmoreceptive afferents may be conveyed to the DMV via inhibitory synapses.  相似文献   
60.
We examined the relation between various drugs used for treating high blood pressure and the incidence of acute myocardial infarction with a case-control design. Four hospitals taking care of all patients in Oslo with acute myocardial infarction participated with a total of 95 hypertensive men and women under 75 years of age who had had an acute myocardial infarction. A total of 329 age and sex matched controls were hypertensive citizens in Oslo without myocardial infarction. Frequency of treatment with drugs and odds ratio of risks with these drugs were calculated. The risk (odds ratio) of myocardial infarction for drug treatment during the last five years versus non drug treatment was 0.70 (95% confidence interval 0.42-1.18). The risk for diuretics and bT-blockers tested against no treatment was 0.91 (0.52-1.61). The corresponding risk for vasodilating drugs was 0.43 (0.20-0.91). Four weeks of exposure to aL-blockers, on the other hand, tested against other drug treatments, indicated an odds ratio of 4.62 (1.01-24.0) for individuals with a history of angina. These data confirm that treatment with diuretics and bT-blockers has only little effect on the incidence of myocardial infarction. As a whole, vasodilators are associated with a significant reduction in this incidence, but aL-blockers enhance the risk in patients with angina.  相似文献   
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