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991.
ObjectiveTo explore the role of a four-item Global Rating Scale (GRS) that could be used in place of the Appraisal of Guidelines, Research and Evaluation II (AGREE II).Study Design and SettingA mixed four-factor design was used (User Type, Evaluation Type, Clinical Topic, Guideline). Participants were asked to read and evaluate a guideline using both the AGREE II draft and GRS or GRS only and to complete a series of questions regarding overall guideline quality, adoption, utility, and acceptability.ResultsOne GRS item varied as a function of User Type. Each item was a significant predictor of participants' outcome measures. All items were rated as useful by stakeholders. The GRS rating scores, outcome measures, and usefulness scores did not vary between the two Evaluation Type conditions. Correlations between the GRS and the outcome measures were stronger compared with those between the AGREE II draft and these measures.ConclusionAlthough the GRS is less sensitive than the AGREE II in detecting differences in guideline quality as a function of User Type, its items did predict important outcome measures related to guideline adoption. The GRS may play a role in guideline evaluation, although further study is warranted.  相似文献   
992.
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994.
A new report has indicated that different stages of the menstrual cycle are associated with fluctuations in the amount of HIV present in genital fluids. In the study women were followed for two full menstrual cycles. Samples of cervical fluid were taken and analyzed to determine the presence of HIV RNA. The HIV viral load was variable during the cycle; the level was greatest during active menstruation, and lowest immediately following menses. In addition, HIV RNA levels were higher than blood plasma viral load two to three weeks after menses and again at menses.  相似文献   
995.
We demonstrated previously that variables of macrophage activation are associated with the development and progression of the arthritic lesion in the model of adjuvant induced arthritis. This association was investigated further by assessing the ability of antiarthritic agents to modulate variables of macrophage activation in direct comparison to effects on the arthritic lesion. Whereas indomethacin effectively reduced hindpaw edema, it had no significant effect on Ia expression or on any measurement of activation. Prednisolone inhibited hindpaw edema and the production of interleukin-1 (IL-1) by splenic macrophages. Only methotrexate inhibited hindpaw edema and all variables of macrophage activation (PGE2 and IL-1 production, cyanine dye accumulation) as well as the influx of Ia positive macrophages into synovial tissue.  相似文献   
996.
CLINICAL PROBLEM: To examine the evidence supporting the recent National Cholesterol Education Program (NCEP) recommendation that low to moderate levels of cholesterol should be aggressively managed in patients with coronary heart disease (CHD). METHODS: Cohort studies and clinical trials with angiographic or clinical endpoints, that included CHD patients with low to moderate levels of cholesterol, were systematically identified through a MEDLINE search and critically reviewed. SYNOPSIS: None of the cohort studies show that a moderate level of cholesterol confers significantly increased risk of CHD death, although a pooled relative risk of 1.14 (95% CI 1.08 to 1.4) suggests that there may be a slight excess risk. Of five angiographic trials of CHD patients with moderate levels of cholesterol, two demonstrated no improvement in angiographic endpoints with intensive lipid-lowering therapy and the other three are difficult to interpret since they included other interventions in addition to the cholesterol-lowering regimen. No large clinical trial with clinical endpoints has been reported for CHD patients with low to moderate levels of cholesterol. RECOMMENDATIONS: The recommendation to treat CHD patients who have low to moderate levels of cholesterol with diet or drugs is not based on convincing evidence of efficacy. This is in clear contrast to the recommendation for CHD patients with high levels of cholesterol, for whom there is definitive clinical trial evidence of benefit from cholesterol-lowering therapy. While we await clinical trial results for CHD patients with low to moderate levels of cholesterol, clinicians and patients must consider the possible disadvantages of therapy in relation to the uncertain benefit. Received from the Section of General Internal Medicine, Department of Medicine, Veterans Affairs Medical Center, and the University of Minnesota School of Medicine, Minneapolis, Minnesota.  相似文献   
997.
Despite the overall effectiveness and availability of highly active antiretroviral therapy (HAART), 1500 HIV-related deaths still occur annually in New York City. In considering ways to further reduce deaths, we assessed the contribution of concurrent HIV/AIDS diagnosis to HIV-related mortality in New York City among persons newly diagnosed with AIDS. We used Cox regression to conduct a retrospective cohort analysis of HIV-related mortality among 15,211 residents age 13+ reported with AIDS to the population-based HIV/AIDS registry between January 2002 and June 2005. Concurrent HIV/AIDS diagnosis was defined as a diagnosis of AIDS occurring within 1 month of initial diagnosis of HIV. HIV-related mortality was 20.2% among persons diagnosed concurrently and 12.2% among those diagnosed nonconcurrently (p < 0.0001). Concurrent HIV/AIDS was associated with more than twice the risk of HIV-related death within the 4 months after diagnosis (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.94-2.65) but no increased risk thereafter (HR 1.12, 95% CI 0.77-1.61). Other significant predictors of death included injection drug use and birth in the Caribbean or Latin America. After 4 years 11.9% of all HIV-related deaths were attributable to a concurrent HIV/AIDS diagnosis. Public health initiatives that facilitate early diagnosis of HIV may reduce HIV-related mortality by giving people the opportunity to initiate care and begin treatment with HAART before immunosuppression places them at risk for opportunistic illness and death.  相似文献   
998.
BackgroundSubstantial blood loss and the requirement for blood transfusion remain major considerations for hepatic surgeons. We analysed the impact of a systematic protocol aimed at reducing intraoperative blood loss and homologous blood (HB) transfusion associated with hepatic resection.MethodsProspective clinical data were collected from 151 elective liver resections performed during the period between 1980 and 1999. Further data directly related to blood loss and anaesthesia were retrospectively collected from the anaesthetic intra-operative record. Strategies implemented in 1991 included preoperative autologous blood donation, low central venous pressure anaesthesia, aprotinin administration, ultrasonic dissection, hepatic vascular inflow occlusion and a Cell Saver. Blood loss and transfusion requirements were studied before and after the implementation of these strategies.ResultsThere was no difference in the patient demographics, indications for operation or the scope of resections in the two time periods evaluated. Blood-saving strategies resulted in decreased estimated blood loss (4500 mL vs. 1000 mL p<0.001). In addition, the number of patients requiring transfusion decreased (91.8% vs. 25.5% respectively, p<0.001) and the mean number of units of HB transfusion was lower (I 3.7 vs. 2.3, p<0.001). Morbidity and mortality were also decreased (57.1% vs. 25.5%, p<0.001 and 10.2% and 4.9% p<0.001, respectively). No complications directly referrable to low CVP anesthesia were identified.ConclusionSystematic implementation of strategies designed to control blood loss are effective and may reduce morbidity and mortality associated with hepatic resections.  相似文献   
999.
Ultrastructural pathology of skeletal muscle in various rheumatic diseases   总被引:1,自引:0,他引:1  
Seventy-three muscle biopsies from patients with various rheumatic diseases were analyzed using immunofluorescence, light, and ultrastructural microscopy. Pathologic data were correlated with clinical variables of local muscle and systemic disease. Light and immunofluorescence findings were generally normal. Ultrastructure differed from normals, showing a spectrum of nonspecific changes. There were no disease specific pathologic features. Myofibrillar damage was the most common pathologic change, with atrophy or degeneration occurring in a majority of biopsies. Semiquantitative analysis showed a general correlation between the extent of pathologic change and muscle weakness.  相似文献   
1000.
Distribution of lipids in 8,500 men with coronary artery disease   总被引:1,自引:0,他引:1  
In the present study we measured fasting lipid profiles in over 8,500 community-living men with coronary artery disease (CAD) to determine the distribution of lipid abnormalities in this population: 81% were white and 16% black; mean age 62.9 ± 8 years; mean total cholesterol 214 ± 41 mg/dl; low-density lipoprotein (LDL) cholesterol 140 ± 37 mg/dl; high-density lipoprotein (HDL) cholesterol 39 ± 11 mg/dl; and triglycerides 190 ± 142 mg/dl. After adjusting for age, the only significant difference between blacks and whites was a higher HDL cholesterol in blacks (45 vs 38 mg/dl, p < 0.003). With use of cut points established by the National Cholesterol Education Program, 87% or subjects had high LDL cholesterol (≥100 mg/dl), 38% had low HDL cholesterol (<35 mg/dl), and 33% had high triglycerides (>200 mg/dl). We estimated that 42% of men with CAD would be definite candidates for cholesterol-lowering medication according to the National Cholesterol Education Program guidelines and that 41% of those in whom cholesterol-lowering medication would not be definitely indicated had low levels of HDL cholesterol. We conclude that (1) black men with CAD have substantially higher HDL cholesterol than white men, (2) almost 90% of male patients with CAD are candidates for dietary intervention and >40% may need medications to lower LDL cholesterol, and (3) 40% of patients without a definite indication for cholesterol-lowering medications have low levels of HDL cholesterol.  相似文献   
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