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21.
Objective: To analyze clinical, laboratory and treatment features associated with death in a childhood-onset SLE population. Patients and methods: Patients with childhood-onset SLE followed at the State University of Campinas, Brazil, between 1980 and 2002 were included. Data on clinical and laboratory features of the disease were collected regularly. Logistic regression was used for analyzing association between clinical and laboratory features and death. Kaplan–Meyer tests were used to estimate the survival curves. Results: Of 61 patients identified, six were lost to follow-up during the first year of disease. The mean follow-up period of the remaining 55 patients was 3.25 years (SD=1.2). Mean SLICC/ACR-DI score was 4.9 (SD=3.4). Death occurred in 12 (21.8%) of 55 patients. Direct causes of death were: infection in six (50%), stroke in four (33.3%), and renal insufficiency in two (16.7%). Five patients (41.7%) died during the first 5 years of disease due to infection. Male gender (p=0.004; OR=9.1; 95% CI=7.6–21.0), infection (p=0.001; OR=4.2; 95% CI=1.6–15.2) and nephritis (p=0.02; OR=2.3; 95% CI=1.3–5.2) were independent factors associated with death in the multivariate analysis. The global survival rate adjusted for duration of disease was 93.9% in the first year of disease, 88.9% in the second year, 80.8% in the fifth year and 48.1% in 20 years of follow-up. When comparing survival curves, male gender, the presence of infection during the course of the disease and the presence of nephritis during follow-up had a worse survival. Conclusion: Male gender, the presence of infection and nephritis were independent risk factors for death in our Brazilian cohort. Damage did not independently influence survival in this study. 相似文献
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Smoking is a high-risk behavior that affects the health and economic welfare of society. Thus, it is important to quantify the economic burden smoking places on social institutions in the United States.
OBJECTIVE: The purpose of this review paper is to analyze smoking cost studies and to provide estimates that represent the economic costs of smoking from different perspectives of society, and as a whole.
METHODS: Current Contents (1996–), Health Star (1970–), and Medline (1966–) databases were searched through the use of pertinent subject headings and key words: tobacco use, smoking, cost, and economics. The internet was utilized to identify potential sources of epidemiological and cost information on smoking. Recent cost-of-illness studies using different methodologies: human capital, incidence, and prevalence were chosen for review based on their relevance.
RESULTS: Preliminary results indicate that the published cost studies available underestimate the "true" costs of smoking. The most current articles approximate annual direct medical costs to health care payers of $50 billion (1993); inflating to 1997 equals $59 billion or $1,200 per smoker. Although the latest cost studies do not attempt to estimate indirect costs, past studies have found indirect costs to be 1.5–2 times the direct costs. Therefore, using direct and indirect costs we estimate total smoking costs to be $150 billion (1993); inflating to 1997 equals $176 billion or $3,500 per smoker.
CONCLUSION: Quantifying the cost of smoking is a difficult task due to tobacco use infiltrating many aspects of life and the dependency of cost on perspective. Cost-of-illness studies provide cost estimation data which can be useful in aiding decision-makers who are allocating health care resources. 相似文献
OBJECTIVE: The purpose of this review paper is to analyze smoking cost studies and to provide estimates that represent the economic costs of smoking from different perspectives of society, and as a whole.
METHODS: Current Contents (1996–), Health Star (1970–), and Medline (1966–) databases were searched through the use of pertinent subject headings and key words: tobacco use, smoking, cost, and economics. The internet was utilized to identify potential sources of epidemiological and cost information on smoking. Recent cost-of-illness studies using different methodologies: human capital, incidence, and prevalence were chosen for review based on their relevance.
RESULTS: Preliminary results indicate that the published cost studies available underestimate the "true" costs of smoking. The most current articles approximate annual direct medical costs to health care payers of $50 billion (1993); inflating to 1997 equals $59 billion or $1,200 per smoker. Although the latest cost studies do not attempt to estimate indirect costs, past studies have found indirect costs to be 1.5–2 times the direct costs. Therefore, using direct and indirect costs we estimate total smoking costs to be $150 billion (1993); inflating to 1997 equals $176 billion or $3,500 per smoker.
CONCLUSION: Quantifying the cost of smoking is a difficult task due to tobacco use infiltrating many aspects of life and the dependency of cost on perspective. Cost-of-illness studies provide cost estimation data which can be useful in aiding decision-makers who are allocating health care resources. 相似文献
24.
Human lymphocytes and Chinese hamster ovary (CHO) cells in culture were exposed for 12 1/2 hours to a magnetic resonance imaging apparatus with a 2.35-Tesla magnet and 100-MHz radio frequency emission. The cells were examined for cytogenetic damage manifested either as chromosome aberrations or sister chromatid exchanges (SCEs), which constitute very sensitive measures of genetic and cellular damage. In either unstimulated or stimulated human lymphocytes, as well as in exponentially growing CHO cells, no increase in either chromosome aberrations or SCEs was found as a result of exposure to these MR conditions. The data indicate that long-term exposure to MR imaging conditions far exceeding those to be found in the clinical situation does not cause cytogenetic damage. 相似文献
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OBJECTIVE: To determine if sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection, risk assessment, and education tools provided as part of office-based primary care reduce adolescent risky sexual behaviors. DESIGN: A randomized intervention trial with 3- and 9-month follow-up. SETTING: Five staff-model managed care sites in Washington, DC (n = 19 pediatricians). PATIENTS: Consecutive 12- to 15-year-olds receiving a general health examination; 81% minority. Participation rate = 215/432 (50%). Nine-month follow-up rate = 197/215 (92%). INTERVENTION: Audiotaped STD risk assessment and education about staying safe (safer = condoms, safest = abstinence). MAIN OUTCOME MEASURES: Adolescent-reported sexual intercourse and condom use. RESULTS: More intervention adolescents reported pediatrician discussion on 11/13 sexual topics. Although more vaginal intercourse (odds ratio [OR] = 2.46, 95% confidence interval [CI] = 1.04-5.84) was reported in the intervention group at 3 months, this was not true of overall sexual intercourse (OR = 1.55, 95% CI =.73-3.32). More sexually active adolescents reported condom use in the intervention group at 3 months (OR = 18.05, 95% CI = 1.27-256.03). At 9 months, there were no group differences in sexual behaviors; however, more signs of STD were reported by the control (7/103) than the intervention group (0/94). CONCLUSIONS: STD risk assessment and education tools administered in a single office visit facilitated STD/HIV prevention education. Any impact on sexual activity and condom use was short-lived. Further research is needed to develop brief, office-based sexual risk reduction for young adolescents. 相似文献
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The effect of a graded exercise protocol on phosphorus-31 magnetic resonance (MR) spectroscopy of calf skeletal muscle in nine healthy (control) subjects and 16 patients with symptomatic peripheral arterial occlusive disease (PAOD) was assessed. Ankle-brachial pressure indexes were obtained in all 16 patients, and 10 patients underwent peripheral arteriography. Temporal profiles of pH and the inorganic phosphorus (Pi) index were calculated from the spectra. A Pi-index recovery rate constant was calculated for each subject. Arteriograms were graded by calculating the runoff resistance in the limb of interest. The pH profiles during exercise did not differ significantly between the PAOD patients and control subjects. The Pi-index recovery rate constant in the PAOD patients was significantly (P less than .01) smaller than in the control subjects. There was no significant correlation between recovery rate and the ankle-brachial pressure indexes, but there was a strong negative correlation between recovery rates and angiographic resistance grades, with smaller recovery rate constants in patients with increased arterial resistance. It is concluded that P-31 MR spectroscopy shows promise as a direct measure of tissue perfusion. 相似文献
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目的:观察褪黑素对自身免疫性肝炎大鼠模型外周血淋巴细胞亚群的影响方法:实验于2004-10/2006-10在解放军第一二三医院南京军区肝病中心实验室完成。①实验材料:Wistar大鼠,雄性,3月龄,体质量(230±20)g,购自上海斯莱克实验动物有限责任公司。褪黑素:美国Sigma公司产品,临用前以无水乙醇溶解,再加生理盐水配制,使乙醇浓度为0.1%,置4℃冰箱保存备用。②实验方法:采用弗氏完全佐剂加肝细胞特异性脂蛋白法制作大鼠自身免疫性肝炎模型。将建模成功大鼠随机分为模型对照组、褪黑素注射组及猪促肝细胞生长素注射组,每组20只。褪黑素注射组褪黑素2mg/kg腹腔注射,1次/d,猪促肝细胞生长素注射组2mg/kg猪促肝细胞生长素腹腔注射,1次/d,模型对照组与正常对照组均用含0.01%乙醇的生理盐水腹腔注射。③实验评估:60d后检测各组大鼠外周血淋巴细胞亚群浓度。结果:①CD4 细胞≤39.5只,均为褪黑素注射组动物,肝炎组织活动性指数≤8分。22只CD4 细胞>39.5%动物中,4只肝炎组织活动性指数≤8分,其中2只为褪黑素注射组动物,2只为模型对照组动物。18只肝炎组织活动性指数>8分,均为模型对照组动物。②18只CD4 细胞≤39.5%褪黑素注射组动物中,17只肝纤维化指数≤4分,1只肝纤维化指数4分;22只动物CD4 细胞>39.5%,2只肝纤维化指数≤4分,为模型对照组动物,20只肝纤维化指数>4分,褪黑素注射组2只,模型对照组18只。③CD4 细胞≤39.5%,肝组织血管病变均为1级,>39.5%时,2级以上血管病变为90.9%。18只CD4 细胞≤39.5%褪黑素注射动物血管病变为1级。22只CD4 细胞百分比>39.5%,2只血管病变为1级,为模型对照动物,17只血管病变为2级,褪黑素注射组2只,模型对照组15只。3只血管病变为3级,为模型对照动物。④CD4 细胞≤39.5%时,83.3%血管内皮细胞生长因子表达呈弱阳性,CD4 细胞>39.5%时,81.8%血管内皮细胞生长因子表达呈强阳性,提示CD4 细胞与血管内皮细胞生长因子表达有关。⑤模型对照组外周血CD4 细胞数和CD4 /CD8 比值均明显高于其他组(P<0.05),CD8 细胞与其他组无明显差异(P>0.05)。褪黑素注射动物与猪促肝细胞生长素注射动物相比,无明显差异(P>0.05)。结论:褪黑素对自身免疫性肝炎模型大鼠外周血CD4 细胞有较强的抑制作用。 相似文献