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991.
The 2-vessel occlusion approach to produce global ischemia in rats requires concomitant reduction of systemic blood pressure. We have utilized the hypotensive effect of halothane administrated by artificial respiration to prevent respiratory arrest and to ensure stable physiological conditions. Systemic blood pressure was reduced to 40-45 mmHg by instant adjustments of the halothane concentration. Bilateral occlusion of the carotid arteries caused a profound and reproducible ischemia, as analyzed by laser-Doppler flowmetry. In the rats exposed to 11, 12, or 13 min of ischemia, 5% died and 5% developed seizures. The extent of neuronal death in CA1 was highly correlated to the duration of ischemia. Following 11 min of ischemia, CA1 neuronal cell death, as analyzed by Fluoro-Jade, was absent 1 day after injury, variable at day 4, and consistent at day 7. The numbers of cresyl violet- and NeuN-positive neurons at day 7 were 8% and 20% of control, respectively. OX42 immunoreactivity was low and variable at day 4, but pronounced at day 7. In conclusion, this rat global ischemia model is relatively simple to perform, has a low mortality, and produces a profound and highly reproducible delayed cell death of hippocampal CA1 neurons. 相似文献
992.
993.
Video-assisted thoracoscopic surgery (VATS) has become an alternative treatment tool for a variety of spinal conditions in the last two decades. This endoscopic or "keyhole" approach minimizes the chest wall morbidity related to the traditional thoracotomy. The current indications for VATS are the same as in any open anterior spinal surgery. This article reviews the outcomes of VATS treatments in thoracic disc diseases, fractures, tumors and vertebral osteomyelitis. In addition, we have described our "learning curve" and surgical techniques using video-assisted thoracoscopic spinal releases and instrumentation in the treatment of 50 patients with adolescent idiopathic scoliosis. 相似文献
994.
995.
Effect of atorvastatin upon platelet activation in hypercholesterolemia, evaluated by flow cytometry 总被引:2,自引:0,他引:2
Hyperlipidemia is a well established risk factor for cardiovascular disease and atherothrombotic events, in which platelet activation also plays a significant role. However, very few studies have addressed platelet activation in hypercholesterolemia, the potential effect of lipid lowering drugs upon platelet hyperfunction, and the question of whether changes in the latter are correlated to normalization of plasma lipids. This study used whole blood flow cytometry to assess in vivo and in vitro platelet activation in a group of 33 patients with hypercholesterolemia, and also the ex vivo effect of atorvastatin (20 mg/day) upon such activation. A control group of 40 normolipidemic volunteers matched in terms of age, sex and added risk factors to the patient group was used. The results showed that hypercholesterolemic patients had in vivo a significantly greater percentage of GPIIb/IIIa- and phosphatidylserine-positive platelets compared with the control group (4.62+/-3.51% and 2.58+/-1.19% versus 2.73+/-1.08% and 1.54+/-0.68%, respectively). In vitro response of CD62 expression to thrombin was also greater in the patients than in the controls (92.51+/-6.00% versus 89.63+/-10.72%, p<0.05). Atorvastatin therapy normalized platelet hyperfunction in the patients studied and reduced GPIIb/IIIa response to ADP (from 82.65+/-6.43% to 75.84+/-4.89%, p<0.01). A significant correlation can be seen between such normalization and the decrease in plasma levels of total and LDL cholesterol. 相似文献
996.
997.
Reid G Anand S Bingham MO Mbugua G Wadstrom T Fuller R Anukam K Katsivo M 《Journal of clinical gastroenterology》2005,39(6):485-488
Every minute of every day more and more children die of diarrheal diseases and women, and girls become infected by HIV. An estimated 7,000 women become infected each day. While many valiant efforts are being made to address these issues, until now they have proved to be markedly ineffective. The notion that lactic acid bacteria, formulated into food or dietary supplements, could have a role to play in slowing the morbidity and mortality associated with HIV/AIDS and gastroenteritis, is built upon sound clinical findings and scientific investigations, yet no international efforts have been placed in this approach, to date. We hereby summarize the reasons why such efforts should be made, provide an example of one model being set up in sub-Saharan Africa, and challenge the international community to consider the potential benefits of probiotics, especially for communities not reached by governmental and nongovernmental agencies. 相似文献
998.
Castedo E Moñivas V Cabo RA Monguió E Montero CG Burgos R Serrano-Fiz S Téllez de Peralta G González M Cavero MA Ugarte J 《Revista espa?ola de cardiología》2005,58(7):864-867
Valve repair is the best surgical treatment for mitral regurgitation. In the present article we describe the results of mitral valve repair in patients with chronic mitral regurgitation treated at our center during the last eight years. The degree of correction of valve insufficiency, functional benefit, in-hospital morbidity and mortality, postoperative outcome of ventricular function, and middle-term overall and reoperation-free survival are analyzed. 相似文献
999.
Data gathered from a study of reserve component (RC) soldiers who were activated during the spring of 2002, following the terrorist attacks of September 11, 2001, suggested that they were concerned about how the effects of their activation affected their civilian employment. Therefore, the purpose of this study was to obtain this information from the civilian employers of these RC soldiers. Most civilian employers who participated in this study (N = 28) were male (89%) and working in law enforcement (39%). Fifty-six percent of employers gave consent to be interviewed by telephone. Although supervisors reported difficulties in several areas of operation and aspects of the RC activation, they still supported the activation of their RC employees and their military mission. This study is a significant start to illuminating the important roles that both RC employees and their civilian employers play in homeland defense. 相似文献
1000.
Nikken JJ Oei EH Ginai AZ Krestin GP Verhaar JA van Vugt AB Hunink MG 《Radiology》2005,234(1):116-124
PURPOSE: To assess predictive value of a short magnetic resonance (MR) imaging examination in addition to or instead of radiography in patients with acute wrist trauma to identify patients who require additional treatment versus those who do not and can be discharged without further follow-up. MATERIALS AND METHODS: Informed consent was obtained from all participating patients; the institutional review board approved the randomized controlled trial and use of data to create prediction models. Of 90 patients (37 female, 53 male; mean age, 40.0 years), 87 with acute wrist trauma were randomized to undergo radiography (n = 43) or radiography and a short MR imaging examination with low-field-strength dedicated extremity MR system (n = 44). Age, sex, trauma mechanism, presence of tenderness of the anatomic snuffbox, radiographic results, MR imaging results, and treatment data were collected. Univariable and multivariable logistic regression analysis was used to create four models for prediction of treatment need. RESULTS: Thirty-six patients had one or more fractures; one patient had a marked soft-tissue lesion. In univariable analysis, age (odds ratio, 1.02; 95% confidence interval: 1.00, 1.05), anatomic snuffbox tenderness (odds ratio, 2.31; 95% confidence interval: 0.90, 5.96), radiographic results (odds ratio, 31.2; 95% confidence interval: 8.90, 109), and positive MR imaging results versus MR imaging not performed (odds ratio, 1.86; 95% confidence interval: 0.57, 6.06) were significantly predictive of treatment need. In multivariable analysis, radiographic results (odds ratio, 24.7; 95% confidence interval: 6.59, 93.1) and positive MR imaging results (odds ratio, 6.28; 95% confidence interval: 1.27, 31.0) were significantly predictive of treatment need. Negative MR imaging results were not significantly predictive (odds ratio, 0.87; 95% confidence interval: 0.20, 3.82). CONCLUSION: A short MR imaging examination with a low-field-strength MR imaging system following radiography in initial evaluation of patients with acute wrist trauma has additional value in prediction of treatment need; it does not have value in identification of patients who can be discharged without further follow-up. 相似文献