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排序方式: 共有4421条查询结果,搜索用时 15 毫秒
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Joy H Lewis Meredith L Kilgore Dana P Goldman Edward L Trimble Richard Kaplan Michael J Montello Michael G Housman José J Escarce 《Journal of clinical oncology》2003,21(7):1383-1389
PURPOSE: Although 61% of new cases of cancer occur among the elderly, recent studies indicate that the elderly comprise only 25% of participants in cancer clinical trials. Further investigation into the reasons for low elderly participation is warranted. Our objective was to evaluate the participation of the elderly in clinical trials sponsored by the National Cancer Institute (NCI) and assess the impact of protocol exclusion criteria on elderly participation. PATIENTS AND METHODS: We conducted a retrospective analysis using NCI data, analyzing patient and trial characteristics for 59,300 patients enrolled onto 495 NCI-sponsored, cooperative group trials, active from 1997 through 2000. Our main outcome measure was the proportion of elderly patients enrolled onto cancer clinical trials compared with the proportion of incident cancer patients who are elderly. RESULTS: Overall, 32% of participants in phase II and III clinical trials were elderly, compared with 61% of patients with incident cancers in the United States who are elderly. The degree of underrepresentation was more pronounced in trials for early-stage cancers than in trials for late-stage cancers (P <.001). Furthermore, protocol exclusion criteria on the basis of organ-system abnormalities and functional status limitations were associated with lower elderly participation. We estimate that if protocol exclusions were relaxed, elderly participation in cancer trials would be 60%. CONCLUSION: The elderly are underrepresented in cancer clinical trials relative to their disease burden. Older patients are more likely to have medical histories that make them ineligible for clinical trials because of protocol exclusions. Insurance coverage for clinical trials is one step toward improvement of elderly access to clinical trials. Without a change in study design or requirements, this step may not be sufficient. 相似文献
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Rosie Ashbolt Jenny Barralet Robert Bell Dennis Bittisnich Andrew Black Barry Combs Christine Carson Scott Crerar Craig Dalton Joy Gregory Michelle Harlock Gillian Hall Geoff Hogg Martyn Kirk Karin Lalor Tony Merritt Sally Munnoch Jennie Musto Lillian Mwanri Leonie Neville Chris Oxenford Rhonda Owen Jane Raupach Cameron Sault Russell Stafford Barbara Telfer Hassan Vally Kefle Yohannes 《Communicable diseases intelligence》2005,29(1):85-88
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Dania Genobile Joanna Gaston Graham F Tallis Joy E Gregory Julia M Griffith Mary Valcanis Diane Lightfoot John A Marshall 《Communicable diseases intelligence》2004,28(2):225-229
Outbreaks of shigellosis in child care are not commonly reported in Australia, however Shigella bacteria can easily spread in these settings. We report an outbreak of shigellosis in a child care centre and discuss the control measures implemented. This investigation identified 20 confirmed cases of Shigella sonnei biotype g and a further 47 probable cases in children and staff who attended a child care centre, and their household contacts. The investigation highlighted the importance of stringent control measures and protocols for dealing with outbreaks of Shigella and other enteric infections in the child care setting, and the importance of prompt notification by both doctors and child care centres, of suspected outbreaks. 相似文献
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Biology of tooth replacement in amniotes 总被引:1,自引:0,他引:1
Tooth replacement is a common trait to most vertebrates, including mammals. Mammals, however, have lost the capacity for continuous tooth renewal seen in most other vertebrates, and typically have only 1–2 generations of teeth. Here, we review the mechanisms of tooth replacement in reptiles and mammals, and discuss in detail the current and historical theories on control of timing and pattern of tooth replacement and development. 相似文献
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