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The in vitro activities of clarithromycin and tigecycline alone and in combination against Mycobacterium avium were assessed. The activity of clarithromycin was time dependent, highly variable, and often resulted in clarithromycin resistance. Tigecycline showed concentration-dependent activity, and mycobacterial killing could only be achieved at high concentrations. Tigecycline enhanced clarithromycin activity against M. avium and prevented clarithromycin resistance. Whether there is clinical usefulness of tigecycline in the treatment of M. avium infections needs further study.  相似文献   
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The Bunyaviridae family is comprised of more than 350 viruses, of which many within the Hantavirus, Orthobunyavirus, Nairovirus, Tospovirus, and Phlebovirus genera are significant human or agricultural pathogens. The viruses within the Orthobunyavirus, Nairovirus, and Phlebovirus genera are transmitted by hematophagous arthropods, such as mosquitoes, midges, flies, and ticks, and their associated arthropods not only serve as vectors but also as virus reservoirs in many cases. This review presents an overview of several important emerging or re-emerging bunyaviruses and describes what is known about bunyavirus-vector interactions based on epidemiological, ultrastructural, and genetic studies of members of this virus family.  相似文献   
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The former Callahan Mine Site in Brooksville, ME, is an open-pit, hardrock mine site in an intertidal system, thus providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Copper, zinc, cadmium, and lead concentrations in sediment, whole water, and Atlantic killifish (Fundulus heteroclitus) were evaluated at sites in Goose Pond (GP; Callahan Mine Site) and at reference sites. The metal concentrations of sediment, water, and fish were spatially distinct and significantly greater at the mine site than in the reference estuary. Sediment concentrations were particularly elevated and were above probable effects levels for all four metals adjacent to the tailings pile. Even in this well-mixed system, water metal concentrations were significantly elevated adjacent to the tailings pile, and concentrations of Cu and Zn were above ambient water-quality criteria for chronic marine exposure. Neither organic matter in the sediment nor salinity or pH of the water explained the metal concentrations. Adjacent to the tailings pile, killifish metal body burdens were elevated and were significantly related to both sediment and aqueous concentrations. In conclusion, (1) the contaminated sediment and seepage from the tailings impoundment and waste rock pile no. 3 create a continual flux of metals into the water column, (2) the metals are bioavailable and bioconcentrating as evident in the killifish tissue concentrations, and (3) Callahan Mine is directly affecting metal bioaccumulation in fauna residing in the GP estuary and, potentially, in Penobscot Bay by the way of “trophic nekton relay.”  相似文献   
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Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatological disease of childhood. Despite the current availability of potent disease-modifying anti-rheumatic medications, most children still experience a chronic course with prolonged periods of active disease. Goals for treatment should include disease remission with optimal physical functioning allowing children to lead normal lives without structural joint damage. However, recent studies demonstrate only moderate rates of remission, indicating that JIA is not as benign as previously thought. The probability of attaining remission within 5 years is approximately 50% across all JIA categories except for polyarthritis when the outlook is significantly worse. Longer term, about 50% of adults with JIA suffer from persistent inflammation and disability.There is a shift towards early aggressive treatment with the intention to switch off inflammation since there may be a ‘window of opportunity’ before the disease becomes chronic. There is clear evidence for improved outcome in adult patients treated with this approach (‘treat to target’) but limited paediatric evidence to date. The explosion in anticytokine agents for treatment of disease resistant to conventional therapy has expanded our armamentarium, improving short term clinical outcomes, but it is still unclear whether we have achieved significant improvements in outcome longer term. This review describes the disease and current and longer-term data on outcomes for this common chronic childhood condition.  相似文献   
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Aim. To ascertain the socio‐cultural meaning and consequences of tuberculosis among people of Somali origin living in the UK. Background. In countries where treatment has not been readily available, tuberculosis has become highly stigmatized. Research in Somalia has documented the stigma and social isolation associated with tuberculosis which acts as a powerful deterrent to sufferers acknowledging their illness. The Somali community in the UK is diverse and dynamic: little is known about how tuberculosis is understood, or how stigma is articulated and experienced post‐migration. Design. A focused ethnography was undertaken. Method. A total of 48 individual interviews were undertaken in 2008–2009 with community leaders, Somali community members and tuberculosis patients to explore the social meaning of tuberculosis and perceived consequences of the disease. Eight focus groups were undertaken involving 56 participants. Vignettes concerning tuberculosis were used to prompt discussion of community norms and socio‐cultural constructions of tuberculosis. Data were analysed using the ‘Framework’ approach. Findings. Most participants were familiar with tuberculosis, its characteristics and treatment. However, many participants held misconceptions about how the disease spread and its prognosis. Tuberculosis was perceived as a stigmatizing disease. Somalis with tuberculosis were considered likely to experience felt and enacted stigma with fear of discrimination in the form of social isolation influencing the extent to which people with tuberculosis disclosed their condition. Conclusion. Nurses should understand the socio‐cultural meaning and consequences of tuberculosis for Somalis to educate the community through public health initiatives and support patients and their families.  相似文献   
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