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71.
Influence of clinical history upon detection of nodules and other lesions   总被引:4,自引:0,他引:4  
The authors reexamined a suspected difference in the effects of clinical information upon detection of nodules vs. more diverse lesions by directly incorporating classification specificity into detection ROC analysis. Categorical prompts, correct for specific abnormalities, led to detection superior to unprompted reading when non-nodule trials (various lesion types) were analyzed. Trials that contained pulmonary nodules, or contained no lesions but had been preceded by "possible tuberculosis" or "rule out metastatic disease" prompts, failed to demonstrate the diagnostic prompt superiority. Perceptual responses may differ when nodules are compared with more complex lesions.  相似文献   
72.
73.
Aims: The aims of this study were to evaluate patterns of handgrip (HG) strength in relation to gender and age in English schoolchildren and to compare this with existing data and produce reference data for this population. Methods: The HG of 7147 English schoolchildren (3773 boys and 3374 girls) aged 10–15.9 years was measured using a portable Takei handgrip dynamometer (Takei Scientific Instruments Co. Ltd, Tokyo, Japan). Centile data were produced using the Generalized Additive Models for Location, Scale and Shape. Z‐scores were generated using existing data for European children. Age and gender interactions were analysed using analysis of covariance. Results: In boys and girls, significant increases in HG were found between every age‐group (p < 0.001). Boys were significantly stronger than girls at every age (p < 0.001) and the boys’ age‐related increase was significantly greater than the girls’ (p < 0.001). Conclusion: This study provides reference data for handgrip strength in English schoolchildren. Handgrip strength in English children is broadly similar to existing European data, after adjusting for mass and stature. These data could be used for clinical or athletic screening of low and high strength in this population.  相似文献   
74.
The Institute of Medicine has warned of the harm of food marketing to children from television to new media channels such as the Internet. The authors identified and analyzed the techniques used to engage children on websites from cereal companies—the third largest food marketer to children. The authors found that top breakfast cereal manufacturers maintain child-oriented websites, using strategies unique to the Internet to capture and maintain children's attention. These include branded engagement techniques such as advergames, videos, site registration, and viral marketing, including inviting friends to join the site. The authors found 3 progressive levels of telepresence on child-targeted cereal websites: sites with more than 1 engaging feature, multiple techniques present on individual pages, and the construction of a virtual world. Using Internet traffic data, the authors confirm that these techniques work: cereal marketers reach children online with lengthier and more sophisticated engagements than are possible with traditional, passive media such as television advertisements or product packaging. Despite the cereal manufacturer's self-regulatory pledge to improve their marketing to children, their marketing practices exploit children's susceptibility to advertising by almost exclusively promoting high-sugar cereals using deeply engaging techniques.  相似文献   
75.
This commentary addresses a little explored aspect of prevention, namely, how public health practitioners conceptualize the roles of industries whose business interests may be at odds with physical activity and eating nutrient-rich foods. Taking their cues from successful campaigns in tobacco control, many public health advocates have framed obesity as a battle with the food industry. Such framing presents problems when it exacerbates existing tensions between practitioners in nutrition and physical activity, and alienates potential fitness industry partners. Creating healthy environments requires reframing expectations of all industries that influence physical activity and inactivity. A broader view of the influence of corporate practices on physical and social environments will help both physical activity and nutrition advocates identify what they can do together, and in partnership with the business sector, to create environments that promote activity and nutritious eating.  相似文献   
76.
Dershaw  DD; Masterson  ME; Malik  S; Cruz  NM 《Radiology》1985,156(2):541-544
A 1-mm-thick, stationary, ultrahigh-strip-density, focused grid was evaluated with respect to patient radiation dose and mammographic image quality as it affected the resolution of microcalcifications and masses. Radiographic technique was varied to determine the most useful alteration to improve image quality with the grid. Results from 89 patients demonstrated that no improvement in diagnostic ability was found in women with fatty breasts. As breast density increased, the advantage of the grid technique became more apparent. Grid mammography also often solved the problem of questionable microcalcifications with improved visualization of their number and geometry.  相似文献   
77.
Framing battles in public health illustrate the tension in our society between individual freedom and collective responsibility. This article describes how two frames, market justice and social justice, first articulated in a public health context by Dan Beauchamp, influence public dialogue on the health consequences of corporate practices. The authors argue that public health advocates must articulate the social justice values motivating the changes they seek in specific policy battles that will be debated in the context of news coverage. The authors conclude with lessons for health education practitioners who need to frame public health issues in contentious and controversial policy contexts. Specific lessons include the importance of understanding the existing values and beliefs motivating the public health change being sought, the benefits of articulating core messages that correspond to shared values, and the necessity of developing media skills to compete effectively with adversaries in public debate.  相似文献   
78.
Reproductive factors have been suggested to have an impact on the development of Hodgkin's disease (HD) in women. In the San Francisco Bay Area, the authors conducted a population-based case-control study addressing the effects of reproductive experience and hormone use on HD risk. Cases were 370 women with HD diagnosed at ages 19-79 years between July 1988 and December 1994. Controls were 450 community women found through random digit dialing. Among the 312 cases and 325 controls interviewed, HD risk was related to parity versus nulliparity but only among never nursers (odds ratio (OR)=2.2, 95% confidence interval (CI): 1.0, 5.0). Risk was marginally related to having uterine fibroids (OR=0.6, 95% CI: 0.5, 1.0) and long-term versus short-term hormone use (OR=0.7, 95% CI: 0.4, 1.0) and was significantly related to recurrent miscarriage (OR=2.8, 95% CI: 1.1, 7.4). Among women aged 35-54 years, for whom the sex difference in incidence is largest, nursing decreased risk; among never nursers, a parity of 1 lowered risk and higher parity increased risk; long-term hormone use lowered risk; and recurrent miscarriage increased risk. Among women under age 35 years, endometriosis lowered HD risk; the lack of significant findings for most other variables may reflect selection bias in controls. Among older women, no significant associations were observed, although hormone use appeared to be protective. These data suggest that steroid hormones may affect HD development.  相似文献   
79.
Regression modeling of consumption or exposure variables classified by type   总被引:1,自引:0,他引:1  
Consumption or exposure variables, as potential risk factors, are commonly measured and related to health effects. The measurements may be continuous or discrete, may be grouped into categories and may, in addition, be classified by type. Data analyses utilizing regression methods for the assessment of these risk factors present many problems of modeling and interpretation. Various models are proposed and evaluated, and recommendations are made. Use of the models is illustrated with Cox regression analyses of coronary heart disease mortality after 24 years of follow-up of subjects in the Framingham Study, with the focus being on alcohol consumption among these subjects.  相似文献   
80.
Occult pulmonary embolism: a common occurrence in deep venous thrombosis   总被引:3,自引:0,他引:3  
Ventilation-perfusion scans were used in a prospective study to determine the prevalence of occult pulmonary embolus in proven deep venous thrombosis. Fifty-eight patients without symptoms of pulmonary embolism, but with venographically proven deep venous thrombosis, were subjected to chest radiographs, 99mTc macroaggregated-albumin perfusion scans, and 133Xe ventilation scans. Of the 49 patients with deep venous thrombosis proximal to the calf veins, 17 (35%) had high-probability scans. Of all 58 patients, only 12 (21%) had normal scans. When the study population was compared with a group of 430 patients described in reports of pulmonary perfusion in asymptomatic persons, a significantly higher percentage of high-probability scans was found in the study population with deep venous thrombosis. Baseline ventilation-perfusion lung scanning is valuable for patients with proven above-knee deep venous thrombosis.  相似文献   
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