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Toll-like receptor (TLR) 2 and TLR5, but not TLR4, are required for Helicobacter pylori-induced NF-kappa B activation and chemokine expression by epithelial cells 总被引:11,自引:0,他引:11
Smith MF Mitchell A Li G Ding S Fitzmaurice AM Ryan K Crowe S Goldberg JB 《The Journal of biological chemistry》2003,278(35):32552-32560
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摘要:【目的】本研究通过百日咳杆菌黏附素(PRN)基因的分段克隆表达及其在BALB/c小鼠的主动和被动免疫保护试验筛选PRN中的保护性抗原肽。【方法和结果】利用大肠杆菌进行PRN的完整蛋白、N端和C端多肽及其RI和RII区域多肽(双拷贝)的表达,命名为GST-PRN、GST-PN、GST-PC、GST-2PRI和GST-2PRII。Western blot检测证实5种表达产物均具有良好的反应原性。在主动免疫保护试验中,5种表达产物均能诱导小鼠产生较高的PRN抗体水平;当使用3 LD50的支气管败血波氏杆菌 相似文献
54.
Sinomanglietia glauca is a critically endangered species described from Jiangxi Province in the 1990s. Recently two populations were discovered from Yongshun County of west Hunan Province, about 450 km away from those in Jiangxi. Because of the new findings and the poor reproducibility inherent to RAPD and ISSR markers of previous studies, the population structure of this rare species was reanalyzed with chloroplast PCR‐SSCP (single‐stranded conformation polymorphism), including all of four recorded populations. The results showed that two distinct haplotypes characterized Jiangxi and Hunan populations separately, with no genetic variation occurring within regions. We postulated that this surprising pattern might result from habitat fragmentation and demographic bottlenecks during and/or after the Quaternary glaciation. On the basis of the pronounced genetic structure, two evolutionarily significant units (ESUs) were recommended for effective conservation of S. glauca. 相似文献
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Orme CD Davies RG Olson VA Thomas GH Ding TS Rasmussen PC Ridgely RS Stattersfield AJ Bennett PM Owens IP Blackburn TM Gaston KJ 《PLoS biology》2006,4(7):e208
Large-scale patterns of spatial variation in species geographic range size are central to many fundamental questions in macroecology and conservation biology. However, the global nature of these patterns has remained contentious, since previous studies have been geographically restricted and/or based on small taxonomic groups. Here, using a database on the breeding distributions of birds, we report the first (to our knowledge) global maps of variation in species range sizes for an entire taxonomic class. We show that range area does not follow a simple latitudinal pattern. Instead, the smallest range areas are attained on islands, in mountainous areas, and largely in the southern hemisphere. In contrast, bird species richness peaks around the equator, and towards higher latitudes. Despite these profoundly different latitudinal patterns, spatially explicit models reveal a weak tendency for areas with high species richness to house species with significantly smaller median range area. Taken together, these results show that for birds many spatial patterns in range size described in geographically restricted analyses do not reflect global rules. It remains to be discovered whether global patterns in geographic range size are best interpreted in terms of geographical variation in species assemblage packing, or in the rates of speciation, extinction, and dispersal that ultimately underlie biodiversity. 相似文献
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Cheng ZJ Jiang YF Ding H Severson D Triggle CR 《Canadian journal of physiology and pharmacology》2007,85(3-4):404-412
In this study, we tested the hypothesis that spontaneously diabetic TallyHo (TH) mice, a novel polygenic model for type 2 diabetes, will exhibit endothelial dysfunction associated with an increased contribution from endothelium-derived contractile factors (EDCF). The cellular mechanisms underlying the increased contribution of EDCF were explored in 16 and 30-week-old male TH and age-matched male C57BL/6J mice (n=4-9). Blood glucose and serum lipid profiles were markedly increased in the TH mice. Superoxide generation, assessed with a lucigenin chemiluminescence assay, was markedly increased in the aortae of TH mice. Endothelium-dependent vascular relaxations and contractions to acetylcholine (ACh), but not endothelium-independent relaxations to sodium nitroprusside, were impaired and vascular contractions to phenylephrine were significantly enhanced in aortae from TH mice. Nomega-nitro-L-arginine methyl ester markedly increased the ACh-induced contractions in TH mice, whereas SQ29548, a thromboxane receptor antagonist, and cytochrome P450 (CYP) inhibitors 17-octadecynoic acid and sulfaphenazole, the latter being specific for CYP2C6 and 2C9, decreased and (or) normalized the contractile response to ACh in TH mice. The present study indicates that enhanced contribution of prostaglandin H2/thromboxane A2 receptor and CYP, likely CYP2C6 and 2C9, play a critical role in the pathogenesis of increased EDCF in the aortae of type 2 diabetic TH mice. 相似文献
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本文对山东省曲阜市1982-1994年二代棉铃虫发生动态的虫情与相应年份的气象资料进行了数量分析,应用Fuzzy优选识别原理,建立了二代棉铃虫发生动态的Fuzzy优选识别模式·对历史资料进行回代验证,其历史拟合率为 100%.书 1995,1996 两年的观测数据资料作为独立样本进行试报,预测结果与实际一致.本研究为农业害虫发生动态的预测预报提供了一种新的研究方法. 相似文献