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BACKGROUND: Estimates of colorectal cancer test use vary widely by data source. Medicare claims offer one source for monitoring test use, but their utility has not been validated. We compared ascertainment of sigmoidoscopy and colonoscopy between three data sources: self reports, Medicare claims, and medical records. MATERIALS AND METHODS: The study population included Medicare enrollees residing in North Carolina (n = 561) who had participated in a telephone survey on colorectal cancer tests. Medicare claims were obtained for the 5 years preceding the survey (January 1, 1998 to December 31, 2002). Information about sigmoidoscopy and colonoscopy procedures conducted in physician offices were abstracted from medical records. Sensitivity, specificity, positive predictive value, negative predictive value, agreement, and kappa statistics were calculated using the medical record as the gold standard. Agreement on specific procedure type and purpose was also assessed. RESULTS: Agreement between claim and medical record regarding whether an endoscopic procedure had been done was high (over 90%). Agreement between self report and medical record and between self report and claim was good (79% and 74%, respectively). All three data sources adequately distinguished the type of procedure done. None of the data sources showed reliable levels of agreement regarding procedure purpose (screening or diagnostic). CONCLUSION: Medicare claims can provide accurate information on whether a patient has undergone colorectal endoscopy and may be more complete than physician medical records. Medicare claims cannot be used to distinguish screening from diagnostic tests. Recognizing this limitation, researchers who use Medicare claims to assess rates of colorectal testing should include both screening and diagnostic endoscopy procedures in their analyses.  相似文献   
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This is a first person account of the experiences, frustrations and joys of a woman with a disability pursuing the dream of having a child. The author describes the difficulties of dealing with the medical establishment and the problems that she encountered when pursuing fertility services. The article then goes on to discuss the author's experiences during pregnancy and her early experiences as a mother. She concludes by comparing her experiences as a mother with other women who do not have a disability  相似文献   
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Introduction: Asthma mortality has declined overall because of a range of public health initiatives. In western countries, the majority of asthma deaths now occur in people over the age of 50. The reasons for the poorer response of older age groups to public health asthma initiatives are not known. Objectives: We undertook a study to investigate the disease perspectives of older people with asthma and barriers which may exist and prevent optimal asthma care. Methods: Fifty‐five participants (16 male and 39 female) aged over 50 from an inner city, suburban area and a rural region were recruited. Lung function was measured, and questionnaire data on asthma symptoms, knowledge and control, medication use and respiratory health were collected. Participants were also interviewed in‐depth, and the quantitative and qualitative data were triangulated. Results: Participants with a duration of asthma for >30 years reported significantly fewer symptoms and better quality of life irrespective of asthma severity, indicating less appreciation of symptoms in those with a long asthma duration. Interviews revealed this was related to previous asthma management strategies when treatment options were limited. Participants with a recent diagnosis sought understanding of asthma and the reason for their illness. Initiatives to improve asthma care in older people need to reflect these findings. Conclusions: Self‐management strategies for older people need to be tailored according to the time of disease onset and the duration of disease. Please cite this paper as: Goeman DP, O’Hehir RE, Jenkins C, Scharf SL and Douglass JA. ‘You have to learn to live with it’: a qualitative and quantitative study of older people with asthma. The Clinical Respiratory Journal 2007; 1:99–105.  相似文献   
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A novel gene therapy approach for treating damaged cartilage is proposed that involves placing endotoxin-free cDNA containing the gene for bone morphogenetic protein-2 (BMP-2) in type I collagen sponges and then transferring the naked plasmid DNA construct to the injury site. A full-thickness cartilaginous defect in rabbits implanted with plasmid containing a marker gene (beta-galactosidase) showed expressed protein as detected by immunostaining. At 1 week postimplantation, mesenchymal cells subjacent to the defect had incorporated the implanted naked plasmid DNA and, once transfected, served as local bioreactors, transiently producing the gene product. Plasmids containing the gene for BMP-2 implanted in collagen sponges in cartilage lesions stimulated hyalinelike articular cartilage repair at 12 weeks postimplantation, nearly equivalent in quality to that induced by collagen sponges with recombinant BMP-2 protein. Our approach circumvents the risks of inflammation and immunogenic response associated with the use of viral vectors. Naked plasmid DNA as a vehicle for transferring therapeutic genes has been shown to be effective in a therapeutic model within rabbit articular cartilage and appears to be safe and cost effective.  相似文献   
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Genotyping of platelet alloantigens with the possibility of using any type of cellular material as a source of DNA has become a preferred procedure, particularly in thrombocytopenic patients when platelet counts are too low for phenotyping. Recently human platelet antigen 1 (HPA-1) has been identified as an inherited risk factor for coronary thrombosis. The different detection methods currently used have disadvantages for large-scale DNA diagnosis, including the need for electrophoresis (allele-specific restriction enzyme analysis, amplification with sequence-specific primers) or the potential risk of reduced specificity (allele-specific oligonucleotide hybridization). In this report we describe the adaptation of an automated oligonucleotide ligation assay to genotype HPA-1 in polymerase chain reaction (PCR)-amplified DNA samples. HPA-1a and HPA-1b phenotypes corresponded to the results of the different genotyping assays. The genotypes determined with the ELISA-based PCR-oligonucleotide ligation assay were in 100% concordance with the results obtained by conventional allele-specific restriction enzyme site analysis and PCR amplification with sequence-specific primers. The automated oligonucleotide ligation assay provides a rapid, reliable, nonisotopic method to genotype human platelet antigens that can rapidly be applied to large population screening.  相似文献   
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