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排序方式: 共有638条查询结果,搜索用时 15 毫秒
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Two cases of intracerebral pneumatocele following trauma are presented. One to two months after initial treatment both patients had deteriorating neurologic status. The diagnosis was made by radiography. When a pneumatocele is suspected clinically, computed tomography can play a vital role in determining the precise location of the gas collection, its relationship to the fracture site, and the amount of mass effect on the brain. 相似文献
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Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade
of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this
study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and
pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific
TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant
role in mediatingtat induced T-cell apoptosis. 相似文献
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Zapka JG White MJ Reed G Ockene JK List E Pbert L Jolicoeur D Reiff-Hekking S 《American journal of preventive medicine》2005,28(4):338-345
BACKGROUND: Professional societies and government organizations have promoted guidelines and best practices that encourage clinicians to routinely integrate cessation counseling into patient encounters. While research in health maintenance organizations has demonstrated that the development and maintenance of office systems do enable clinicians' smoking-cessation services, little is known about the adoption of system strategies in diverse organizations serving disadvantaged populations. METHODS: Data were collected via face-to-face interviews from November 2001 to October 2002 using a standardized systems assessment checklist at service delivery sites of 83 funded community health service agencies, which included hospitals, community health centers, and other organizations (e.g., substance abuse, mental health, and multiservice). The content of the structured assessment reflected system elements with proven effectiveness that have been included in guidelines and best practices recommendations. Detailed information was collected on the implementation strategies. RESULTS: This study found considerable attention to systems that support cessation services in diverse healthcare organizations, but much remains to be done. There is a wide diversity of implementation strategies employed, with varied degrees of sophistication. CONCLUSIONS: A major challenge is to develop systems capable of providing population-based feedback to, and between, providers, which will enable further quality improvement efforts. 相似文献
36.
Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial 总被引:55,自引:12,他引:43
Anderson GL Limacher M Assaf AR Bassford T Beresford SA Black H Bonds D Brunner R Brzyski R Caan B Chlebowski R Curb D Gass M Hays J Heiss G Hendrix S Howard BV Hsia J Hubbell A Jackson R Johnson KC Judd H Kotchen JM Kuller L LaCroix AZ Lane D Langer RD Lasser N Lewis CE Manson J Margolis K Ockene J O'Sullivan MJ Phillips L Prentice RL Ritenbaugh C Robbins J Rossouw JE Sarto G Stefanick ML Van Horn L Wactawski-Wende J Wallace R Wassertheil-Smoller S;Women's Health Initiative Steering Committee 《JAMA》2004,291(14):1701-1712
Context Despite decades of use and considerable research, the role of estrogen alone in preventing chronic diseases in postmenopausal women remains uncertain. Objective To assess the effects on major disease incidence rates of the most commonly used postmenopausal hormone therapy in the United States. Design, Setting, and Participants A randomized, double-blind, placebo-controlled disease prevention trial (the estrogen-alone component of the Women's Health Initiative [WHI]) conducted in 40 US clinical centers beginning in 1993. Enrolled were 10 739 postmenopausal women, aged 50-79 years, with prior hysterectomy, including 23% of minority race/ethnicity. Intervention Women were randomly assigned to receive either 0.625 mg/d of conjugated equine estrogen (CEE) or placebo. Main Outcome Measures The primary outcome was coronary heart disease (CHD) incidence (nonfatal myocardial infarction or CHD death). Invasive breast cancer incidence was the primary safety outcome. A global index of risks and benefits, including these primary outcomes plus stroke, pulmonary embolism (PE), colorectal cancer, hip fracture, and deaths from other causes, was used for summarizing overall effects. Results In February 2004, after reviewing data through November 30, 2003, the National Institutes of Health (NIH) decided to end the intervention phase of the trial early. Estimated hazard ratios (HRs) (95% confidence intervals [CIs]) for CEE vs placebo for the major clinical outcomes available through February 29, 2004 (average follow-up 6.8 years), were: CHD, 0.91 (0.75-1.12) with 376 cases; breast cancer, 0.77 (0.59-1.01) with 218 cases; stroke, 1.39 (1.10-1.77) with 276 cases; PE, 1.34 (0.87-2.06) with 85 cases; colorectal cancer, 1.08 (0.75-1.55) with 119 cases; and hip fracture, 0.61 (0.41-0.91) with 102 cases. Corresponding results for composite outcomes were: total cardiovascular disease, 1.12 (1.01-1.24); total cancer, 0.93 (0.81-1.07); total fractures, 0.70 (0.63-0.79); total mortality, 1.04 (0.88-1.22), and the global index, 1.01 (0.91-1.12). For the outcomes significantly affected by CEE, there was an absolute excess risk of 12 additional strokes per 10 000 person-years and an absolute risk reduction of 6 fewer hip fractures per 10 000 person-years. The estimated excess risk for all monitored events in the global index was a nonsignificant 2 events per 10 000 person-years. Conclusions The use of CEE increases the risk of stroke, decreases the risk of hip fracture, and does not affect CHD incidence in postmenopausal women with prior hysterectomy over an average of 6.8 years. A possible reduction in breast cancer risk requires further investigation. The burden of incident disease events was equivalent in the CEE and placebo groups, indicating no overall benefit. Thus, CEE should not be recommended for chronic disease prevention in postmenopausal women. 相似文献
37.
DiFranza JR Savageau JA Rigotti NA Ockene JK McNeill AD Coleman M Wood C 《Addictive behaviors》2004,29(5):911-919
The Revised Children's Manifest Anxiety Scale (RCMAS) and the Hooked on Nicotine Checklist (HONC) were used to measure trait anxiety and tobacco dependence in a population of 581 adolescents. Smokers demonstrated higher mean RCMAS scores (9.3, S.D.=6.5) than nonsmokers did (7.4, S.D.=6.2, t=-3.7, P<.001). Participants with symptoms of tobacco dependence had higher RCMAS scores (mean=11.6, S.D.=6.0, n=115) than did the participants without symptoms (mean=7.8, S.D.=6.0, n=177, t=-5.3, P<.001). Scores on the RCMAS and the HONC correlated positively (n=292, r=.32, P<.001). Participants who had felt relaxed in response to their first exposure to nicotine were also more likely to develop dependence and to report that stress caused cravings or a need to smoke. Trait anxiety and relaxation in response to the first dose of nicotine were unrelated and appear to be independent risk factors for the development of nicotine dependence and a reliance on tobacco to cope with stress. 相似文献
38.
OBJECTIVE: To develop and test items for the Health Plan Employee Data and Information Set (HEDIS) that assess delivery of the full range of provider-delivered tobacco interventions. MATERIALS AND METHODS: The authors identified potential items via literature review; items were reviewed by national experts. Face validity of candidate items was tested in focus groups. The final survey was sent to a random sample of 1711 adult primary care patients; the re-test survey was sent to self-identified smokers. RESULTS: The process identified reliable items to capture provider assessment of motivation and provision of assistance and follow-up. CONCLUSIONS: One can reliably assess patient self-report of provider delivery of the full range of brief tobacco interventions. Such assessment and feedback to health plans and providers may increase use of evidence-based brief interventions. 相似文献
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Matthews CE Hebert JR Freedson PS Stanek EJ Merriam PA Ebbeling CB Ockene IS 《American journal of epidemiology》2001,153(10):987-995
The authors examined sources of variance in self-reported physical activity in a cohort of healthy adults (n = 580) from Worcester, Massachusetts (the Seasonal Variation of Blood Cholesterol Study, 1994-1998). Fifteen 24-hour physical activity recalls of total, occupational, and nonoccupational activity (metabolic equivalent-hours/day) were obtained over 12 months. Random effects models were employed to estimate variance components for subject, season, day of the week, and residual error, from which the number of days of assessment required to achieve 80% reliability was estimated. The largest proportional source of variance in total and nonoccupational activity was within-subject variance (50-60% of the total). Differences between subjects accounted for 20-30% of the overall variance in total activity, and seasonal and day-of-the-week effects accounted for 6% and 15%, respectively. For total activity, 7-10 days of assessment in men and 14-21 days of assessment in women were required to achieve 80% reliability. For nonoccupational activity, 21-28 days of assessment were required. This study is among the first to have examined the sources of variance in daily physical activity levels in a large population of adults using 24-hour physical activity recall. These findings provide insight for understanding the strengths and limitations of short term and long term physical activity assessments employed in epidemiologic studies. 相似文献