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Osteogenesis imperfecta consists of a group of hereditary connective tissue diseases with fragility of the bone as a general feature. Frequently occurring other characteristics are blue sclerae, opalescent teeth, hearing loss, disorders of the skeleton, and hyperextensibility of the joints. Obliteration and the unusual shape of the pulp chambers may interfere with dental treatment.  相似文献   
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BACKGROUND AND STUDY AIMS: To prevent transmission of infectious agents and to reduce instrument reprocessing time, the use of disposable sheath systems instead of conventionally reprocessed endoscopes has been promoted for flexible sigmoidoscopy. This trial primarily investigated the feasibility of a disposable sheath system for flexible sigmoidoscopy in decentralized colorectal cancer screening. PATIENTS AND METHODS: In an ongoing colorectal cancer screening trial, 226 consecutive participants were randomly allocated to have their flexible sigmoidoscopy performed with either a fiberoptic sigmoidoscope covered with a disposable sheath ("EndoSheath group") or a conventional video colonoscope ("standard colonoscope group"). All examinations were performed at a temporary screening center. The patients' experience was documented using a questionnaire. The feasibility of running temporary screening units was evaluated. RESULTS: Examinations beyond the 60-cm level were excluded. Thus, 113 patients (examined with the disposable instrument) and 87 (standard instrument) were eligible for analysis. When the sheathed system was used, all the devices needed could be satisfactorily transported. A screening center could be set up within a few hours. No differences were observed in patient discomfort. Fewer patients with polyps were observed in the EndoSheath group (48 [42%]), compared with 55 (63%) in the standard colonoscope group; P = 0.005). No significant differences were observed for polyps larger than 5 mm (14 [12%] in the EndoSheath group, 13 [15%] in the standard colonoscope group; P = 0.6). CONCLUSIONS: Using the disposable system, decentralized colorectal cancer screening was easily established. However, fewer polyps were found, possibly due to the fiberoptic nature of the instrument. Sheathed video instruments are desirable and may increase the diagnostic yield.  相似文献   
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Abstract

We are far from having seen the ideal method of screening for colorectal cancer (CRC) and the downsides of screening have not been fully addressed. Funding of adequately sized screening trials with a 10–15-year perspective for endpoints CRC mortality and incidence is difficult to get. Also, with such time horizons, there will always be an ongoing study to be awaited before feeling obliged to invest in the next. New, promising screening methods may, however, emerge far more often than every 10th year, and the knowledge gap may easily widen unless research is made a key responsibility for any ongoing cancer screening program. Previous lost battles on screening research may be won if accepting that scientific evidence may be obtained within the framework of screening programs – provided that they are designed as platforms for Comparative Effectiveness Research (CER). Accepting that CER-based screening programs should be preferred to non-CER programs and seriously compete for their funding sources, then CER screening programs may not be considered so much as contenders for ordinary clinical research funds. Also, CER within a screening framework may benefit patients in routine clinics as shown by screening research in Nordic countries. The Nordic countries have been early contributors to research on CRC screening, but slow in implementing screening programs.  相似文献   
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Purpose/Aim of the study: Chlorhexidine and polyhexanide are frequently used antiseptics in clinical practice and have a broad antimicrobial range. Both antiseptics are helpful medical agents for septic wound treatment with a high potential for defeating joint infections. Their effect on human osteoblasts has, so far, not been sufficiently evaluated. The aim of this study was to investigate the activating potential of polyhexanide and chlorhexidine on inflammatory cytokines/chemokines in human osteoblasts in vitro. Materials and Methods: Human osteoblasts were isolated and cultivated in vitro and then treated separately with 0.1% and 2% chlorhexidine and 0.04% polyhexanide as commonly applied concentrations in clinical practice. Detection of cell structure and cell morphology was performed by light microscopic inspection. Cytokine and chemokine secretion was determined by using a multiplex suspension array. Results: Cell shrinking, defective cell membrane, and the loss of cell adhesion indicated cell damage of human osteoblasts after treatment with both antiseptics was evaluated by using light microscopy. Polyhexanide, but not chlorhexidine, caused human osteoblasts to secrete various interleukins (1β, 6, and 7), interferon γ, tumor necrosis factor α, vascular endothelial growth factor, eotaxin, fibroblast growth factor basic, and granulocyte macrophage colony-stimulating factor as quantified by multiplex suspension array. Conclusions: Both antiseptics induced morphological cell damage at an optimum exposure between 1 and 10 min. But only polyhexanide mediated a pronounced secretion of inflammatory cytokines and chemokines in human osteoblasts. Therefore, we recommend a preferred usage of chlorhexidine in septic surgery to avoid the induction of an inflammatory reaction.  相似文献   
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Immune-mediated bone loss significantly impacts fracture risk in patients with autoimmune disease, but to what extent individual variations in immune responses affect fracture risk on a population level is unknown. To examine how immune responses relate to risk of hip fracture, we looked at the individual variation in a post-vaccination skin test response that involves some of the immune pathways that also drive bone loss. From 1963 to 1975, the vast majority of the Norwegian adult population was examined as part of the compulsory nationwide Norwegian mass tuberculosis screening. These examinations included standardized tuberculin skin tests (TSTs). Our study population included young individuals (born 1940 to 1960 and aged 14 to 30 years at examination) who had all received Bacille Calmette-Guerin (BCG) vaccination after a negative TST at least 1 year prior and had no signs of tuberculosis upon clinical examination. The study population ultimately included 244,607 individuals, whose data were linked with a national database of all hospitalized hip fractures in Norway from 1994 to 2013. There were 3517 incident hip fractures during follow-up. Using a predefined Cox model, we found that men with a positive or a strong positive TST result had a 20% (hazard ratio [HR] = 1.20, 95% confidence interval [CI] 1.01–1.44) and 24% (HR = 1.24, 95% CI 1.03–1.49) increased risk of hip fracture, respectively, compared with men with a negative TST. This association was strengthened in sensitivity analyses. Total hip bone mineral density (BMD) was available for a limited subsample and similarly revealed a non-significantly reduced BMD among men with a positive TST. Interestingly, no such clear association was observed in women. An increased immune response after vaccination is associated with an increased risk of hip fracture decades later among men, possibly because of increased immune-mediated bone loss. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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