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FG Surawicz DR Brightwell WD Weitzel E Othmer 《Canadian Metallurgical Quarterly》1976,133(11):1306-1309
The authors review recent and current literature on the relationship between psychological factors and cancer. They discuss the roles of predisposing personality patterns and emotional stress in the development, site, and course of cancer; the influence of awareness of terminal illness on the behavior of cancer patients; and the management of psychiatric symptoms in these patients. 相似文献
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Protective layers typically act in a passive way by simply separating two sides. Protection is only efficient as long as the layers are intact. If a high level of protection has to be achieved by thin layers, complementary measures need to be in place to ensure safety, even after breakage of the layer-an important issue in medical applications. Here, we present a novel approach for integrating a biocide liquid into a protective film (about 300-500 microm thick), which guarantees that a sufficient amount of biocide is rapidly released when the film is punctured. The film is composed of a middle layer, containing the liquid in droplet-like compartments, sandwiched between two elastomeric boundary layers. When the film is punctured, the liquid squirts out of the middle layer. A theoretical model was used to determine the size and density of droplets that are necessary to ensure a sufficient quantity of biocide is expelled from an adequately elastic matrix to provide protection at the site of damage. We demonstrate the utility of this approach for the fabrication of surgical gloves. 相似文献
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This paper reports early steps in research that seeks to clarify how publications of scientists interact dynamically with
citations and reputation in shaping the evolution of scientific fields. We assume that Lotka's modified law holds for scientific
fields. A primary approach to model publication productivity was published by Yablonsky. In contrast to Yablonsky's unfinished
mathematical approach, our simulation approach is not predominantly driven by insight into the formal generation mechanisms
of certain processes but more theory driven. It considers the evolution of publication and citation distributions over the
histories of scientific fields using both simulated and real historical data. 相似文献
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Daniel Lersch Gheorghe Pascovici Benedikt Birkenbach Bart Bruyneel Jürgen Eberth Herbert Hess Peter Reiter Andreas Wiens Heinz Georg Thomas for the AGATA Collaboration 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,640(1):223
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PURPOSE: Organized interscholastic athletics are an integral part of the educational program at almost every school level. With this growing popularity of sports and their inclusion in more public school programs, it becomes increasingly apparent that additional consideration must be given to the injury problem associated with sport. The North Carolina High School Athletic Injury Study (NCHSAIS) was undertaken to identify patterns of injury among male and female athletes in North Carolina high schools participating in any of 12 sports. Specific aims are to measure the incidence, severity and etiology of injuries; to determine the relationship of demographic factors and protective equipment, exposure to play, and school characteristics to injuries; to study the relationship of coaches' training and experience to injury occurrence; and to compare the incidence and severity of injury among female and male athletes in the same or comparable sports. METHODS: A two-stage cluster sample of 100 high schools in North Carolina was selected for this 4-yr prospective study. RESULTS: Participation by the initial sample or a random replacement was achieved for 91 of the 100 schools. Nonresponse occurred at multiple levels of the sample for this study, and the weekly participation form posed the greatest respondent burden. CONCLUSIONS: The NCHSIAS offers a successful methodology for addressing sports injuries. In this paper we describe the design, methodology, and implementation issues that emerge in conducting a large scale epidemiological study in a population of high school athletes. 相似文献
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NR Every LS Parsons SD Fihn EB Larson C Maynard AP Hallstrom JS Martin WD Weaver 《Canadian Metallurgical Quarterly》1997,96(6):1770-1775
BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality. 相似文献
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