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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   
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Peripheral arterial occlusive disease: P-31 MR spectroscopy of calf muscle   总被引:3,自引:0,他引:3  
Williams  DM; Fencil  L; Chenevert  TL 《Radiology》1990,175(2):381-385
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   
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de Mendez  I; Leto  TL 《Blood》1995,85(4):1104-1110
The phagocyte NADPH oxidase system, as previously defined by cell-free reconstitution, is comprised of five essential components, three of which are produced during late phagocytic differentiation--namely, two cytosolic proteins, p47- and p67-phox--and the large subunit of cytochrome b558, gp91-phox. To confirm that these are the only phagocyte-specific components necessary for oxidase activity in whole cells, the recombinant NADPH oxidase was reconstituted in a heterologous cell line. An undifferentiated multipotent leukemic cell line, K562, which expresses endogenous Rac and the small subunit of the flavocytochrome b558 (p22-phox), was cotransfected with episomal expression vectors containing cDNAs for the three other oxidase components. After 4 days of selection, the complete oxidase system was functionally reconstituted in transfected cells stimulated with phorbol myristate acetate or calcium ionophore. These easily transfected cells provide an ideal model system in which several oxidase components can be genetically manipulated and readily expressed. This system can be used to test the effects of mutations associated with any of the genes affected in chronic granulomatous disease and will facilitate studies on structure-function relationships within several oxidase components. This system will also aid in delineation of upstream regulators functioning through various signaling pathways.  相似文献   
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Background Previous studies reported a close relationship between obesity and insulin resistance in the essential hypertensive patients. Objective In this study, we examined the relationship between the skin fold thickness and insulin resistance then developed a formula to estimate the insulin resistance index according to the skin fold thickness in the essential hypertensive patients. Subjects and Methods Medical records of 80 patients (37 males, 43 females) were reviewed and the data were tabulated. Anthropometric indexes (including height, weight, waist circumference, hip circumference, and skins fold thickness at 5 fatty difference points on the Erdheim diagram), fasting plasma glucose and insulin concentration were recorded. The mean age was 57.0 ?9.2 years. The insulin resistance index was calculated following the Homeostasis Model Assessment (HOMA) formula. Results Compared with the group with BMI < 23 kg/m2, the group with BMI≥23 kg/m2 had higher fasting insulin concentration (8.85±4.97 pmol/L vs 15.60±8.70 pmol/L, P<0.001 ) and higher insulin resistance index in ( 2.15±1,24 vs 3.76±2.22, P<0.001). No significant difference in fasting plasma insulin concentration, insulin resistance index between male and female was observed (P > 0.05). There was a positive correlation between skin fold thickness and the fasting insulin concentration and insulin resistance index. The skin fold thickness at point A8 had the best coefficient correlated with fasting plasma insulin(r=0.79, P < 0.001) and insulin resistance index (r= 0.79, P < 0.001). A formula to estimate the insulin resistance index by skin fold thickness at point A8 as: Insulin resistance index = 0.12×[skin fold thickness at A8 point (mm)] - 1. Conclusion: In the essential hypertensive patients, the formula to estimate insulin resistance index as 0.12×[skin fold thickness at A8 point (mm)]-1 may predict accurately the level of insulin resistance. (J Geriatr Cardiol 2005; 2(4):228-232 )  相似文献   
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目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33~81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。  相似文献   
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