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Strategies for assessing the implications of malformed frogs for environmental health 总被引:7,自引:0,他引:7
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Burkhart JG Ankley G Bell H Carpenter H Fort D Gardiner D Gardner H Hale R Helgen JC Jepson P Johnson D Lannoo M Lee D Lary J Levey R Magner J Meteyer C Shelby MD Lucier G 《Environmental health perspectives》2000,108(1):83-90
The recent increase in the incidence of deformities among natural frog populations has raised concern about the state of the environment and the possible impact of unidentified causative agents on the health of wildlife and human populations. An open workshop on Strategies for Assessing the Implications of Malformed Frogs for Environmental Health was convened on 4-5 December 1997 at the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. The purpose of the workshop was to share information among a multidisciplinary group with scientific interest and responsibility for human and environmental health at the federal and state level. Discussions highlighted possible causes and recent findings directly related to frog deformities and provided insight into problems and strategies applicable to continuing investigation in several areas. Possible causes of the deformities were evaluated in terms of diagnostics performed on field amphibians, biologic mechanisms that can lead to the types of malformations observed, and parallel laboratory and field studies. Hydrogeochemistry must be more integrated into environmental toxicology because of the pivotal role of the aquatic environment and the importance of fates and transport relative to any potential exposure. There is no indication of whether there may be a human health factor associated with the deformities. However, the possibility that causal agents may be waterborne indicates a need to identify the relevant factors and establish the relationship between environmental and human health in terms of hazard assessment. 相似文献
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A comprehensive league table of cost-utility ratios and a sub-table of "panel-worthy" studies. 总被引:5,自引:0,他引:5
OBJECTIVES: The authors compiled a comprehensive league table of cost/QALY ratios, and a standardized table of analyses satisfying selected Reference Case criteria from the USPHS Panel on Cost-Effectiveness in Health and Medicine. METHODS: They identified 228 cost-utility analyses (CUAs) through literature searches, and abstracted data on methods and cost-utility ratios. The subset of "Panel-worthy" analyses used: a societal or broad health-care perspective, community or patient preference weights, net costs, incremental comparisons, and discounting of costs and QALYs. RESULTS: The 228 CUAs included ratios for 647 interventions, ranging from cost-saving to $52,000,000/QALY (median = $12,000/QALY). The standardized table presents 112 ratios that met the "Panel-worthy" criteria, with articles published in recent years more likely to meet all of the criteria. CONCLUSIONS: The comprehensive league table (available on the Web) provides a useful reference, but ratios may not be comparable because of methodologic variations. The standardized table focuses on studies meeting basic methodologic criteria, potentially allowing for better comparison with future Reference Case analyses. Future studies should investigate the quality of analyses' underlying assumptions in addition to whether certain key procedural protocols were met. 相似文献
995.
Patient-oriented learning: a review of the role of the patient in the education of medical students 总被引:1,自引:0,他引:1
Spencer J Blackmore D Heard S McCrorie P McHaffie D Scherpbier A Gupta TS Singh K Southgate L 《Medical education》2000,34(10):851-857
AIM: To explore the contribution patients can make to medical education from both theoretical and empirical perspectives, to describe a framework for reviewing and monitoring patient involvement in specific educational situations and to generate suggestions for further research. METHODS: Literature review. RESULTS: Direct contact with patients can be seen to play a crucial role in the development of clinical reasoning, communication skills, professional attitudes and empathy. It also motivates through promoting relevance and providing context. Few studies have explored this area, including effects on the patients themselves, although there are examples of good practice in promoting more active participation. CONCLUSION: The Cambridge framework is a tool for evaluating the involvement of patients in the educational process, which could be used by curriculum planners and teachers to review and monitor the extent to which patients are actively involved. Areas for further research include looking at the 'added value' of using real, as opposed to simulated, patients; more work on outcomes for patients (other than satisfaction); the role of real patients in assessment; and the strengths and weaknesses of different models of patient involvement. 相似文献
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Cancer registries are a vital source of information on cancer epidemiology and cancer services. Their role has changed dramatically over the past 15 years. A number of factors will affect their future role, including health service changes, information technology, development of clinical datasets and greater demand for both health service and public information. The potential of cancer registration needs to be realized by clinicians and health authorities: how they can use the data, its limitations, and how they can support and influence it through this period of change. A strategic direction is needed so that cancer registries develop into a dynamic, interactive source of knowledge for the twenty-first century. 相似文献
999.
Growth failure is a major complication of chronic hypoxemia, as seen in infants and children with cyanotic congenital heart disease. To determine whether chronic hypoxemia during infancy affects the gastrointestinal tract, we examined small intestinal growth and digestive enzyme activities in chronically hypoxemic newborn lambs and in age-matched controls. Chronic hypoxemia was produced by placing an inflatable occluder around the main pulmonary artery and performing a balloon atrial septostomy. Aortic oxygen saturation was reduced to 60-74% for 2 wk, after which the small intestine was removed for analysis. During chronic hypoxemia, somatic growth rate was decreased to 60% of control (hypoxemic, 135 +/- 20 versus control, 216 +/- 26 g/d, p less than 0.02). No differences in caloric intake were found (hypoxemic, 129 +/- 4 versus control, 128 +/- 4 kcal/kg/d). Chronic hypoxemia did not alter small intestinal growth, as measured by jejuno-ileal weight, jejuno-ileal length, mucosal weight, or mucosal protein or DNA contents. However, sp act of lactase, the principal disaccharidase of the infant lamb intestine, were significantly decreased (hypoxemic, 0.08 +/- 0.01 versus control, 0.146 +/- 0.03 units of enzyme activity/mg DNA, p less than 0.05), as were the total small intestinal contents of lactase (hypoxemic, 61.7 +/- 7.0 versus control, 120.6 +/- 21.7 units of enzyme activity, p less than 0.01). There also were decreases in specific and total activities of other digestive enzymes such as maltase, amino-oligopeptidase, and alkaline phosphatase in hypoxemic intestine that did not achieve statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
L W Rice J M Lage R S Berkowitz A Goodman M G Muto R C Knapp D A Bell 《Gynecologic oncology》1992,46(2):226-229
Preoperative serum CA-125 levels were evaluated in 38 patients who underwent primary surgery for epithelial ovarian tumors of borderline malignancy at the Brigham and Women's Hospital and Massachusetts General Hospital between 1981 and 1990. Surgical staging was Stage I in 25 (66%) patients, Stage II in 2 (5%) patients, Stage III in 10 (26%) patients, and Stage IV in 1 (3%) patient. The mean sizes of mucinous and serous ovarian tumors were 21.9 and 10.3 cm, respectively (P = 0.0002). All 13 patients (100%) with mucinous tumors had Stage I disease, while 12 (50%) of 24 patients with serous tumors were Stage I. Combining all cell types, 10 (40%) of 25 patients with Stage I disease had an elevated preoperative CA-125 level, while 2 (100%) of 2, 9 (90%) of 10, and 1 (100%) of 1 patient with Stage II, III, and IV disease, respectively, had increased preoperative levels. Among patients with serous tumors, 3 (25%) of 12 Stage I patients had an elevated preoperative CA-125 level, while 11 (92%) of 12 Stage II-IV tumors had elevated levels (P less than 0.001). These data suggest that preoperative CA-125 level correlates with stage of disease in patients with serous borderline ovarian tumors. 相似文献