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This study examines the history of the cigarette controversy using the tobacco documents as a roadmap to explore the following four questions: (a) What did tobacco companies know about the health risks of smoking and when did they know it? (b) What evidence is there that tobacco companies conspired to deliberately mislead the public about the health risks of smoking? (c) How were scientists involved in the cigarette controversy? (d) Have tobacco companies changed the way they do business since signing the 1998 Master Settlement Agreement? The tobacco companies knew and for most part accepted the evidence that cigarette smoking was a cause of cancer by the late 1950s. The documents also reveal that the tobacco companies helped manufacture the smoking controversy by funding scientific research that was intended to obfuscate and prolong the debate about smoking and health. Today, the tobacco companies acknowledge that smoking is a cause of disease, but they have not materially altered the way they do business. In our opinion, it is not sufficient for the tobacco industry to merely concede the obvious point that smoking is a cause of disease when it is evident that decades of misinformation has resulted in a public that is massively ignorant about the risks of smoking low-tar cigarettes, nicotine addiction, and secondhand smoke exposure. Public education efforts are still needed to correct these misperceptions along with government oversight to ensure that the industry is not permitted to mislead the public further. If the past 50 years have taught us anything, it is that the tobacco industry cannot be trusted to put the public's interest above their profits no matter what they say.  相似文献   
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The goal of this work was to investigate preference techniques to value potential health gains from treatments of Kaposi sarcoma (KS). The study was designed to take the form of face-to-face interviews with a sample of men with a history of HIV/AIDS ( n=15) or HIV/AIDS and KS ( n=17). The main outcome measure was quality of life (QoL) associated with various KS disease states expressed on a scale from 0 (death) to 1 (perfect health), obtained though time trade-off (TTO) and rating scale techniques. For cutaneous lesions only, the mean TTO preference score value was 0.27. In other words, the men were willing to trade a life expectancy of 5 years for a shorter period (1.4 years) in perfect health. More severe KS health states were rated lower (0.07-0.09). The mean rating scale value for cutaneous lesions only was 0.11 and ranged from -0.10 to -0.04 for the more severe conditions; these values were systematically lower than the TTO ( P=0.014). A large overall potential gain in QoL from treatment (partial response minus stable disease) was found for each condition to be reflected in both the TTO (from 0.31 to 0.55) and the rating scale (from 0.38 to 0.44). Respondents associate KS health states with extremely poor QoL and indicate that large gains are possible through modest treatment effects. While TTO returns higher values than the rating scale, potential gains from treatments were similar. The techniques appear to be suitable for application to QoL and economic evaluation of treatments of KS.  相似文献   
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A cross-sectional radiographic screening was performed on bite-wing pairs (BW) from 1872 10-12 year old schoolchildren in the Greater Worcester, Massachusetts area to assess the prevalence of juvenile periodontitis (JP). The 3-stage screening process entailed: (1) visual identification of possible cases based upon a visual assessment of BW for interproximal crestal bone levels greater than or equal to 2 mm from the cemento-enamel junction (CEJ) on greater than or equal to 1 permanent first molar; (2) identification of probable cases based upon BW from possible cases measured with a transparent ruler calibrated in millimeters; (3) finally, clinical confirmation of JP in consenting probable cases. A total of 1038 subjects were eligible to be included in the study (greater than or equal to 3 mesial sites readable). Of the 1038 eligible subjects, 117 possible and 103 probable cases were identified in stage 1 and stage 2, respectively. A total of 99 probable cases could be contacted and 43 were examined clinically. Two cases of JP were confirmed clinically in stage 3, yielding a prevalence rate of 4.6/1000. Specifically, this report defines a rate of JP in 10-12 year-old schoolchildren for the first time. In addition, these results indicate that BW can be used to identify children with JP from large data sets. However, further studies including complete clinical and radiographic examinations are necessary to determine whether this method is adequate for large epidemiologic studies.  相似文献   
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To evaluate the effect of nerve-graft polarity on function, a 1-cm segment of sciatic nerve was excised and reoriented in three groups of 20 adult Sprague-Dawley rats. In one group, the nerve was cut and anastomosed in the original orientation to act as a control. In the second group, the nerve-graft polarity was reversed 180 degrees. The final group underwent reversal of polarity 180 degrees and was rotated 180 degrees, (i.e., the posterior tibial nerve fascicles proximally were opposite to the peroneal nerve fascicles distally). Functional recovery was evaluated using Bain's modification of de Medinaceli's sciatic functional index (SFI). Rat-track analysis was performed over a 120-day period. Histologic correlation was also performed at the time of sacrifice. From our study, we concluded that reversing nerve-graft polarity, with or without rotation, does not influence subsequent function in this model.  相似文献   
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OBJECTIVE: To compare perceived quality of life (QoL) in patients diagnosed with seasonal affective disorder (SAD) during the winter and summer months. METHODS: Twenty-six patients who were enrolled in an ongoing multicentre study in Canada completed 2 measures of QoL (the 20-item Medical Outcomes Study Short-Form General Health Survey [SF-20] and the Quality of Life Enjoyment and Satisfaction Questionnaire, [Q-LES-Q]) during the winter, when suffering from depression, and again during the summer months. RESULTS: Both general and health-related QoL scores were significantly improved in patients with SAD during the summer months, with scores for the most part falling within normal range. CONCLUSIONS: Perceived QoL in patients with SAD is markedly impaired during the winter months but shows a substantial rebound during the summer months. The findings of this study provide further evidence that SAD is a distinct diagnostic entity.  相似文献   
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