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Aaron M Kipp Jennifer A Lehman Richard A Bowen Patricia E Fox Michael R Stephens Kaci Klenk Nicholas Komar Michel L Bunning 《The American journal of tropical medicine and hygiene》2006,75(4):688-690
To better understand the potential environmental health risk presented by West Nile virus (WNV)-contaminated feces, we quantified the amount of WNV present in the feces of experimentally infected American crows (Corvus brachyrhynchos) and fish crows (Corvus ossifragus). Peak fecal titers ranged from 10(3.5) to 10(8.8) plaque-forming units (PFU)/g for 10 American crows and from 10(2.3) to 10(6.4) PFU/g for 10 fish crows. The presence of infectious WNV in bird feces indicates a potential for direct transmission of WNV. Thus, handlers of sick or dead birds should take appropriate precautions to avoid exposure to fecal material. 相似文献
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Jean Marie Jully Marie Christine Béné Gérard Martin Gilbert Faure 《Journal of clinical periodontology》1986,13(3):223-227
The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases. 相似文献
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There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets. 相似文献
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目的评估十二指肠-空肠导管(Endoluminal Duodeno-Jejunal Tube,EDJT)在活体猪实验动物模型中减缓体重增加的可行性,及其在中短期生存中的安全性。方法本项研究共用8只45kg重的Yorkshire猪,其中3只置入180emEDJT,1只置入360cm EDJT,另4只猪作为对照组。切开十二指肠,将EDJT导管缝合固定在十二指肠近Vater壶腹起始处。结果评估全部猪的不适反应和体重,每日一次,共7周,未发现严重并发症发生。术后7周3组动物的平均体重变化百分率:对照组、180cm组和360cm组分别是22.5%,6%和-2.8%。EDJT组(180cm组、360cm组)体重增加明显减慢,与对照组相比,有统计学意义(P=0.05)。结论EDJT可以安全使用,无肠梗阻、肠套叠或胰腺炎等并发症发生。EDJT可明显减缓体重增加。 相似文献
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Carel Bron Michel Wensing Jo LM Franssen Rob AB Oostendorp 《BMC musculoskeletal disorders》2007,8(1):107