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81.
Since the mid-1980s, the New Zealand health sector has been in a state of continual change. The most radical changes were in the early-1990s, with the creation of an internal market system for public health care delivery. Rural health services, seen to be unviable, were given the option of establishing themselves as 'community trusts', owning and running their own services. Community trusts have since become a feature of rural health care in New Zealand. An expectation was that community trusts would facilitate community participation. This article reports on a study of participation in a rural community health trust. The 'pentagram model' of Rifkin and coworkers, with its five dimensions of participation-needs assessment, leadership, resource mobilization, management and organization-was applied. High levels of participation were found across each of these dimensions. The research revealed additional dimensions that could be added to the framework, including 'sustainability of participation', 'equity in participation' and 'the dynamic socio-political context'. In this regard, it supports recent theoretical work by Laverack (2001) and Laverack and Wallerstein (2001). Finally, the article comments on the future of rural health trusts in the current round of health sector restructuring.  相似文献   
82.
American Cancer Society guidelines for breast cancer screening: update 2003   总被引:34,自引:0,他引:34  
In 2003, the American Cancer Society updated its guidelines for early detection of breast cancer based on recommendations from a formal review of evidence and a recent workshop. The new screening recommendations address screening mammography, physical examination, screening older women and women with comorbid conditions, screening women at high risk, and new screening technologies.  相似文献   
83.
Updates to the American Cancer Society (ACS) guidelines regarding screening for the early detection of prostate, colorectal, and endometrial cancers, based on the recommendations of recent ACS workshops, are presented. Additionally, the authors review the "cancer-related check-up," clinical encounters that provide case-finding and health counseling opportunities. Finally, the ACS is issuing an updated narrative related to testing for early lung cancer detection for clinicians and individuals at high risk of lung cancer in light of emerging data on new imaging technologies. Although it is likely that current screening protocols will be supplanted in the future by newer, more effective technologies, the establishment of an organized and systematic approach to early cancer detection would lead to greater utilization of existing technology and greater progress in cancer control.  相似文献   
84.
Innovative research relating oceans and human health is advancing our understanding of disease-causing organisms in coastal ecosystems. Novel techniques are elucidating the loading, transport and fate of pathogens in coastal ecosystems, and identifying sources of contamination. This research is facilitating improved risk assessments for seafood consumers and those who use the oceans for recreation. A number of challenges still remain and define future directions of research and public policy. Sample processing and molecular detection techniques need to be advanced to allow rapid and specific identification of microbes of public health concern from complex environmental samples. Water quality standards need to be updated to more accurately reflect health risks and to provide managers with improved tools for decision-making. Greater discrimination of virulent versus harmless microbes is needed to identify environmental reservoirs of pathogens and factors leading to human infections. Investigations must include examination of microbial community dynamics that may be important from a human health perspective. Further research is needed to evaluate the ecology of non-enteric water-transmitted diseases. Sentinels should also be established and monitored, providing early warning of dangers to ecosystem health. Taken together, this effort will provide more reliable information about public health risks associated with beaches and seafood consumption, and how human activities can affect their exposure to disease-causing organisms from the oceans.  相似文献   
85.
T Byers  J Mouchawar  J Marks  B Cady  N Lins  G M Swanson  D G Bal  H Eyre 《Cancer》1999,86(4):715-727
BACKGROUND: Cancer incidence and mortality rates both began to decline in the U. S. in the early 1990s. Recognizing the unprecedented potential benefits of accelerating this decline, the American Cancer Society (ACS) has set ambitious challenge goals for the American public for a 25% reduction in cancer incidence rates and a 50% reduction in cancer mortality rates by the year 2015. This analysis examined the feasibility of reaching those goals by estimating future changes in cancer rates that can result from past and future reductions in cancer risk factors. METHODS: Estimates for future declines in cancer risk factors in the U. S. under alternative scenarios were applied to conservative population-attributable risk estimates for cancer incidence and mortality rates in 1990 to estimate cancer rate trends in the year 2015. RESULTS: If the current trends toward a decline in the prevalence of cancer risk factors continue over the next decade, by the year 2015 one can expect a 13% decline in cancer incidence rates and a 21% decline in cancer mortality rates below their 1990 levels. With redoubled efforts to reduce the prevalence of known cancer risk factors further, by the year 2015 cancer incidence rates could be reduced by 19% and cancer mortality rates reduced by 29%. Such redoubled efforts would equate to approximately 100,000 cancer cases and 60,000 cancer deaths prevented each year by the year 2015. CONCLUSIONS: Past reductions in cancer risk factors in the U.S. population have led to recent declines in the rates of cancer incidence and mortality in the U.S. Redoubled efforts to act on current knowledge regarding how to prevent, detect, and treat cancer can result in attaining approximately 80% of the ACS challenge goal for cancer incidence rates and 60% of the ACS challenge goal for cancer mortality rates by the year 2015. New findings from cancer research are needed and will have to be applied quickly if the ACS challenge goals are to be met fully.  相似文献   
86.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
87.
88.
Pulmonary lymphangitic spread of carcinoma: appearance on CT scans   总被引:6,自引:0,他引:6  
Stein  MG; Mayo  J; Muller  N; Aberle  DR; Webb  WR; Gamsu  G 《Radiology》1987,162(2):371-375
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS.  相似文献   
89.
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
90.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.  相似文献   
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