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This case study examines a nonlegislative task force as it struggled to reach internal consensus despite external political constraints. The study highlights the convergence of politics and science, revealing complex issues likely to be confronted by advocates and public health officials. Three themes capture participants' experiences: context, sizing up the opportunities and constraints; task force process, tacit strategy to operate outside the political context and play the science card; and aftermath, a glass half full. The task force took advantage of ambiguous parameters, crafting a comprehensive statewide plan to reduce tobacco use and breaking out of the common public health paradigm of allowing budget considerations to drive program design. These internal victories could not sustain a policy success in the legislature. However, the group's product sets science-based standards for future program development, and the task force's process provides valuable insights into other states developing tobacco prevention and control policies.  相似文献   
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Paired groups of male rabbits were challenged with Treponema pallidum and Mycobacterium bovis BCG. One group had been sensitized to BCG by inoculation 3 weeks before challenge. All animals were challenged intradermally at multiple sites with T. pallidum alone, BCG alone, and both organisms into the same sites. The resulting lesions were followed clinically and histologically. BCG lesions enlarged more rapidly in sensitized rabbits, but they were otherwise no different from those in the controls. T. pallidum lesions enlarged and regressed simultaneously in both groups, but in the BCG-sensitized animals they became twice as large as those in the unsensitized rabbits. Mixed BCG-T. pallidum lesions showed the greatest differences in the two groups of animals. Like the pure BCG lesions, they enlarged more rapidly in the sensitized rabbits but began to recede after 1 week. The corresponding lesions in the controls enlarged more slowly and reached their maximum size after 3 weeks when the receding lesions in the sensitized animals were much smaller. The most marked histological-histochemical difference between the two groups of animals was in the number and activation of macrophages. These cells were more numerous in the mixed lesions of BCG-sensitized animals than in similar lesions of the controls and more activated as determined by beta-galactosidase staining. Although sparsely distributed, activated macrophages were more numerous in the pur T. pallidum lesions of sensitized animals than in those of control animals. Silver-stained sections revealed fewer treponemes in mixed lesions of sensitized animals than in the mixed lesions of control animals. Quantitation of treponemes in pure T. pallidum versus mixed lesions was determined in two groups of rabbits challenged intratesticularly. The total number of treponemes per testis in the mixed lesions of BCG-sensitized rabbits was significantly less than the number in the mixed lesions of control animals, and also less than the number in pure T. pallidum lesions of both groups of animals.  相似文献   
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Treponema pallidum were extracted from testicular syphilomas of corticosteroid-treated rabbits and purified by differential centrifugation. The steroid therapy allowed a longer holding time for infected rabbits, which produced greater treponeme yields, averaging 1.58 × 1010 treponemes per rabbit. The treatment, which also diminished cellular infiltration and increased the extracellular mucoid material in lesions, produced much cleaner suspensions than preparations from nontreated animals. Most of the treponemes in the purified suspensions were still motile, and none carried demonstrable host immunoglobulin. The preparations were free of recognizable host tissue debris and they contained, on the average, 1.9 × 10−7 μg of protein per treponeme.  相似文献   
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Advances in Health Sciences Education - When physicians do not estimate their diagnostic accuracy correctly, i.e. show inaccurate diagnostic calibration, diagnostic errors or overtesting can occur....  相似文献   
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Cardiac safety assessment in drug development concerns the ventricular repolarization (represented by electrocardiogram (ECG) T‐wave) abnormalities of a cardiac cycle, which are widely believed to be linked with torsades de pointes, a potentially life‐threatening arrhythmia. The most often used biomarker for such abnormalities is the prolongation of the QT interval, which relies on the correct annotation of onset of QRS complex and offset of T‐wave on ECG. A new biomarker generated from a functional data‐based methodology is developed to quantify the T‐wave morphology changes from placebo to drug interventions. Comparisons of T‐wave‐form characters through a multivariate linear mixed model are made to assess cardiovascular risk of drugs. Data from a study with 60 subjects participating in a two‐period placebo‐controlled crossover trial with repeat ECGs obtained at baseline and 12 time points after interventions are used to illustrate this methodology; different types of wave form changes were characterized and motivated further investigation. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Background and Purpose . Although physical therapists (PTs) have extensive knowledge of body mechanisms and injury prevention, work‐related musculoskeletal disorders (WRMD) are quite common in this population. The purposes of this study were: to determine the prevalence and impact of WRMD among Israeli PTs; to investigate WRMD risk factors and to identify preventive strategies used by PTs; and to compare the risk of injuries in two professional settings: rehabilitation centres (RCs) and outpatient clinics (OPCs). Method . A validated, modified Cromie questionnaire, translated into Hebrew, was distributed to the PTs at their workplaces. The relationship between WRMD symptoms and professional settings was analysed by Pearson chi‐square. The risk models were developed by logistic regression. One hundred and twelve PTs working in OPCs and RCs who defined themselves as healthy individuals were the subjects of this study. Results . Lifetime prevalence of WRMD was 83%. The highest prevalence of WRMD was in the lower back area (80%). Rehabilitation treatment was associated with an increased risk of lower back (odds ratio [OR] = 1.05) and shoulder symptoms (OR = 1.04); manual treatment was associated with an increased risk of wrist/thumb symptoms (OR = 1.11). Discussion . Work in RCs was associated with an increased prevalence of lower back/shoulder symptoms, whereas work in OPCs was associated with an increased prevalence of thumb/wrist symptoms. PT's used different strategies to reduce risk of WRMD, including altering practice technique. The respondents recommended administrative and ergonomic changes in the workplace. Conclusion . Workplace‐specific interventions to reduce WRMD in PTs should be developed and tested in future studies. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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