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排序方式: 共有9386条查询结果,搜索用时 15 毫秒
991.
992.
A Benetos BI Levy P Lacolley F Taillard M Duriez ME Safar 《Canadian Metallurgical Quarterly》1997,17(11):3196-3201
We previously showed that chronic angiotensin-converting enzyme (ACE) inhibition prevented the increase in aortic collagen in spontaneously hypertensive rats (SHRs) independently of blood pressure reduction. The aim of the present study was to determine whether the effects of ACE inhibition on aortic fibrosis were due to inhibition of angiotensin II formation, preservation of bradykinin, or a combination of both. Four week-old SHRs were treated for 4 months with the ACE inhibitor quinapril, quinapril with the bradykinin B2 receptor antagonist Hoe 140, or the angiotensin II AT1 receptor antagonist CI996. Control SHR and Wistar-Kyoto (WKY) rats received a placebo for the same period of time. At the end of the treatment, as compared to conscious SHR and WKY controls, quinapril completely prevented the development of hypertension, whereas quinapril-Hoe 140 and the AT1 receptor antagonist produced only a partial reduction of blood pressure. In relation with blood pressure changes, aortic hypertrophy was significantly prevented by quinapril but not by quinapril-Hoe 140 or CI996. In contrast, aortic collagen accumulation was completely prevented by all three treatments. The study provides evidence that in young live SHRs, the prevention of aortic collagen accumulation is independent of blood pressure changes and bradykinin preservation and involves exclusively angiotensin II inhibition through AT1 receptors. 相似文献
993.
本文在简单介绍IP/X.25路由器的功能和结构的基础上给出一种采用STREAMS机制的路由器TUR在UNIX中的实现.本文还提出一种在面向连接子网服务上实现无连接网络互联的通用有限状态机模型和一种动态地址映射算法.这些方法已应用在TUR中,以提高系统的性能.本文最后给出性能、指标及在TCP/IP网络中的一个应用实例,并讨论这类通信软件普遍存在的问题及其解决思路:互操作测试. 相似文献
994.
995.
MC Hou TC Yen HC Lin BI Kuo CH Chen FY Lee RS Liu FY Chang SD Lee 《Canadian Metallurgical Quarterly》1997,92(10):1875-1878
OBJECTIVE: Endoscopic injection sclerotherapy and variceal ligation are two popular endoscopic methods used to treat esophageal variceal hemorrhage. These two methods have not been compared with regard to esophageal dysfunction after treatment. This is a prospective investigation of esophageal dysmotility after endoscopic injection sclerotherapy and variceal ligation. METHODS: Sequential changes of esophageal motility after endoscopic injection sclerotherapy (n = 25) and variceal ligation (n = 25) were investigated in 50 cirrhotic patients with recent variceal bleeding. Another 22 cirrhotics without esophageal varices were included as controls. Radionuclide esophageal transit tests were performed before initial endoscopic treatment, and 1 and 3 months after variceal eradication. RESULTS: The baseline esophageal transit time was longer in both the sclerotherapy (n = 25, 7.8 +/- 1.4 s) and ligation groups (n = 25, 8.2 +/- 1.8 s) than in controls (n = 22, 6.7 +/- 0.7 s, p < 0.005). The transit time was longer in patients with large varices than in those with small varices (8.3 +/- 1.7 vs. 7.2 +/- 0.7 s, p < 0.05). In the sclerotherapy group, the transit time was prolonged 1 month after variceal eradication, compared with its pretreatment state (n = 20, 7.6 +/- 1.5 vs. 10.0 +/- 2.2 s, p < 0.0001) but was shortened at 3 months compared with 1 month after variceal eradication (n = 12, 10.7 +/- 1.5 vs. 8.6 +/- 2.2 s, p < 0.05). Multiple regression analysis showed that the number of treatment sessions required to eradicate varices was the only significant factor associated with prolonged transit time (p < 0.05). In the ligation group, the transit time changed little at 1 month or 3 months after variceal eradication. CONCLUSIONS: Impairment of esophageal motility can be significant with endoscopic injection sclerotherapy but is reversible. However, endoscopic variceal ligation exerts no significant impact on esophageal motility. 相似文献
996.
997.
BI Kurganov 《Canadian Metallurgical Quarterly》1998,63(3):364-366
In this case report, the anaesthetic management for a removal of phaeochromocytoma undertaken immediately following Caesarean section is described. A 32-year-old female patients was given epidural anaesthesia for Caesarean section, and thereafter, general anaesthesia for a resection of phaeochromocytoma. During surgery, phentolamine, nitroglycerine and prostaglandin E1 were electively administered to decrease blood pressure and heart rate. A live infant was delivered and the supra-adrenal tumour was excised successfully. The patient's post-operative recovery was uneventful. 相似文献
998.
Lysozyme concentration in the gastric juice of 34 patients with peptic ulcer and 10 practically healthy persons was studied. In the patients with peptic ulcer the lysozyme levels in the gastric juice were found to be lower. A significant decrease in the lysozyme concentration was observed in the patients suffering from peptic ulcer for more than 2 years. During the first months of the disease increased levels of lysozyme were recorded. Relationship between the lysozyme concentration in the gastric juice and the acidity of the gastric contents was shown. Decreased concentrations of lysozyme were more pronounced in the patients with increased levels of hydrochloric acid. 相似文献
999.
1000.