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91.
92.
K Michael Cummings Anthony Brown Richard O'Connor 《Cancer epidemiology, biomarkers & prevention》2007,16(6):1070-1076
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
93.
Anthony H Harris Richard H Osborne Catherine L Streeton Helen McNeil 《Supportive care in cancer》2002,10(6):486-493
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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Anthony L. Neely 《Journal of clinical periodontology》1992,19(6):367-372
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
96.
M F Beers A Wali M F Eckenhoff S I Feinstein J H Fisher A B Fisher 《American journal of respiratory cell and molecular biology》1992,7(4):368-378
Surfactant protein C (SP-C) is a lung-specific, hydrophobic peptide found in organic extracts of pulmonary surfactant. Alveolar SP-C (3.5 kD) is produced from proteolytic cleavage of a larger precursor molecule (pro-SP-C; 21 kD). While SP-C is synthesized by type II cells, the pathways for processing and secretion have remained elusive due, in part, to the lack of monospecific antibodies against SP-C or its precursors. This report describes production and characterization of a new antibody directed against pro-SP-C epitopes. Polyclonal antisera (anti-CPRO-SP-C) was prepared using a synthetic peptide corresponding to a portion of rat SP-C cDNA sequence (Ile26-Ser72). This contained amino acids 3-35 of mature SP-C plus additional C-terminal residues (His59-Ser72). On Western blots, anti-CPRO-SP-C competitively reacted to CPRO-SP-C but not to mature SP-C. Immunoblots of in vitro synthesized pro-SP-C confirmed that the antisera also recognized native protein. Immunocytochemistry with anti-CPRO-SP-C demonstrated staining for pro-SP-C peptides in isolated type II cells as well as in alveolar epithelial cells of rat lung sections. Pro-SP-C preferentially co-localized to cells that stained positive for Maclura pomifera antigen. Anti-CPRO-SP-C staining was not observed in lung interstitium, pulmonary vasculature, or several control tissues (brain, heart, and liver were negative). Western blotting of subcellular fractions demonstrated pro-SP-C peptides in plasma membrane (20 kD) and microsomal (20 and 21 kD) fractions with a 16 kD peptide present in lamellar bodies. No pro-SP-C peptides were detected in purified surfactant. These results demonstrate the use of a synthetic peptide to generate specific antiserum against more hydrophilic domains of pro-SP-C sequences and confirm that SP-C propeptides are unique to the lung. 相似文献
97.
Anthony N DeMaria 《Journal of the American College of Cardiology》2006,47(8):1722-1723
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