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PURPOSE: To develop risk-based recommendations for mammographic screening for women in their 40s that take into account the woman's age, race, and specific risk factors. METHODS: We assumed that regular mammographic screening is justified for a 50-year-old woman, even one with no risk factors, and that a younger woman with an expected 1-year breast cancer incidence rate as great or greater than that of a 50-year-old woman with no risk factors would benefit sufficiently to justify regular screening. Recommendations under this criterion were based on age- and race-specific breast cancer incidence rates from the National Cancer Institute's (NCI's) Surveillance, Epidemiology, and End Results (SEER) Program; assessments of risk factors from the Breast Cancer Detection and Demonstration Project (BCDDP); and reports in the literature. RESULTS: Two methods, the exact-age procedure (EAP) and the grouped-age procedure (GAP), were developed. The less precise GAP only requires following a flow diagram. The proportion of white women recommended for screening by the EAP ranges from 10% for 40-year-old women to 95% for 49-year-old women, and the corresponding percentages for black women are 16% and 95%. The assumptions that underlie the guidelines are discussed critically. CONCLUSION: For women or physicians who prefer an individualized approach in deciding whether to initiate regular mammographic screening in the age range of 40 to 49 years, the present report offers recommendations based on individualized risk-factor data and clearly stated assumptions that have an empiric basis. These recommendations can be used to facilitate the counseling process.  相似文献   
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This paper documents and analyzes recent trends in Federal energy research and development programs. In light of the marketplace philosophy of the present Administration, the possible benefits of a strong Federal research program versus the potential advantages of relying on private sector research programs to develop new technology alternatives are analyzed in some detail. The impacts of the Reagan budget cuts and other initiatives on several major energy programs, including nuclear power, photovoltaics, and conservation, are also analyzed. This analysis reveals some of the difficulties inherent in attempting to project the consequences of particular policy decisions in a complex and changing environment, and identifies some of the problems of trying to evaluate the success of particular programs or actions on a limited time scale.  相似文献   
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Discusses common presenting complaints and those of emergent significance that have an organic etiology. The following categories are discussed: head, eyes, ears, throat, neck, cardiac, respiratory, gastrointestinal, genito-urinary, musculoskeletal, and neurologic complaints. It is suggested that many therapists lack adequate medical information to suspect the presence of organic problems when symptoms are indistinguishable from psychogenic/psychosomatic problems. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The NRC's Research Program on Core-Debris/Cavity Interactions comprises two principal elements: (1) an analytical effort focused primarily on development of computer codes needed to predict the potential consequences of risk-significant severe-accident scenarios; and (2) an experimental component to provide insights into the relevant phenomenological processes and to develop the experimental data base necessary for validation of the codes. The analytical activities at Sandia National Laboratories (SNL) focus primarily on refinement and validation of the CORCON and VANESA codes. Two major experimental activities are also based at SNL: (1) the large-scale SURC tests address the thermal-hydraulic phenomena in the cavity as well as aerosol release associated with prototypical core-melt materials in various types of concrete crucibles, while (2) the WITCH and GHOST experiments are concerned with aerosol generation and radionuclide release phenomena. A program of small-scale special-effects tests at Brookhaven National Laboratory (BNL) is coupled to a concomitant model-development and code-validation activity. In addition, measurements are being made at Battelle Columbus Laboratory (BCL) to augment the thermochemical data base needed in the VANESA code to permit refined radiological source-term predictions. The current scope and status of this research is reviewed.  相似文献   
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Rats with lesions to prefrontal cortex (PFC) or caudate nucleus (CN) were compared on tests of conditional associative learning (CAL) that placed varying demands on conditional rule learning and working-with-memory operations that are essential for response selection. Damage to either structure impaired performance, but the respective deficits resulted from disruption of different processes. CN lesions produced a consistent learning deficit that was thought to reflect a basic impairment in forming stimulus-response (S-R) associations. The behavior of PFC rats was more variable and depended on task requirements. When S-R learning or response selection was relatively easy, the PFC was not critical. However, when either component was made more difficult, thus requiring the contribution of strategic processes, PFC damage produced profound impairments. In addition to clarifying the roles of the PFC and CN in CAL, the results provide further evidence that multiple brain regions participate in relatively simple behavioral tasks and that their respective contributions can be dissociated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Geschäftsmodelle   总被引:1,自引:1,他引:0  
The business model concept, although a relatively new topic for research, has garnered growing attention over the past decade. Whilst it has been robustly defined, the concept has so far attracted very little substantive research. In the context of the wide-spread digitization of businesses and society at large, the logic inherent in a business model has become critical for business success and, hence, a focus for academic inquiry. The business model concept is identified as the missing link between business strategy, processes, and Information Technology (IT). The authors argue that the BISE community offers distinct and unique competencies (e.g., translating business strategies into IT systems, managing business and IT processes, etc.) that can be harnessed for significant research contributions to this field. Within this research gap three distinct streams are delineated, namely, business models in IT industries, IT enabled or digital business models, and IT support for developing and managing business models. For these streams, the current state of the art, suggest critical research questions, and suitable research methodologies are outlined.  相似文献   
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