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61.
The evidence that heart failure alone may cause a nephrotic syndrome is inconclusive. Mercurial diuretics, which have also been implicated as a cause of the nephrotic syndrome, had been given in 23 of the 24 well-documented cases.Two cases of heart disease and nephrotic syndrome are described. Glomerular lesions were minimal on light microscopy, but thickening of the glomerular tuft basement membrane and partial fusion of the epithelial cell foot processes were apparent on elecronmicroscopy. The response to prednisone was such as to justify a trial of corticosteroid therapy in such cases despite the presence of cardiac disease. 相似文献
62.
Antiviral memory T-cell responses in the lung 总被引:2,自引:0,他引:2
Woodland DL Ely KH Crowe SR Tighe M Brennan JW Harmsen AG Cauley LS 《Microbes and infection / Institut Pasteur》2002,4(10):1091-1098
Recent studies have identified distinct populations of memory T cells that persist in the lungs following respiratory virus infections, and contribute to the control of secondary virus infections. Here we discuss the establishment, maintenance and recall of memory T cells in the lung. 相似文献
63.
Rezzi S Cavaleiro C Bighelli A Salgueiro L da Cunha AP Casanova J 《Biochemical Systematics and Ecology》2001,29(2):179-188
The composition of 50 samples of essential oil of individual plants of Juniperus phoenicea subsp. turbinata from Corsica was investigated by GC, GC-MS and 13C NMR. alpha-Pinene, beta-phellandrene, alpha-terpinyl acetate, Delta-3-carene, myrcene and alpha-phellandrene were found to be the main constituents. The results were submitted to cluster analysis and discriminant analysis which allowed two groups of essential oils to be distinguished with respect to the content of alpha-pinene, beta-phellandrene and alpha-terpinyl acetate. 相似文献
64.
Background
Many studies have provided algorithms or methods to assess a statistical significance in quantitative proteomics when multiple replicates for a protein sample and a LC/MS analysis are available. But, confidence is still lacking in using datasets for a biological interpretation without protein sample replicates. Although a fold-change is a conventional threshold that can be used when there are no sample replicates, it does not provide an assessment of statistical significance such as a false discovery rate (FDR) which is an important indicator of the reliability to identify differentially expressed proteins. In this work, we investigate whether differentially expressed proteins can be detected with a statistical significance from a pair of unlabeled protein samples without replicates and with only duplicate LC/MS injections per sample. A FDR is used to gauge the statistical significance of the differentially expressed proteins. 相似文献65.
Sequence and structure of Brassica rapa chromosome A3 总被引:1,自引:0,他引:1
Jeong-Hwan Mun Soo-Jin Kwon Young-Joo Seol Jin A Kim Mina Jin Jung Sun Kim Myung-Ho Lim Soo-In Lee Joon Ki Hong Tae-Ho Park Sang-Choon Lee Beom-Jin Kim Mi-Suk Seo Seunghoon Baek Min-Jee Lee Ja Young Shin Jang-Ho Hahn Yoon-Jung Hwang Ki-Byung Lim Jee Young Park Jonghoon Lee Tae-Jin Yang Hee-Ju Yu Ik-Young Choi Beom-Soon Choi Su Ryun Choi Nirala Ramchiary Yong Pyo Lim Fiona Fraser Nizar Drou Eleni Soumpourou Martin Trick Ian Bancroft Andrew G Sharpe Isobel AP Parkin Jacqueline Batley Dave Edwards Beom-Seok Park 《Genome biology》2010,11(9):1-12
Background
The species Brassica rapa includes important vegetable and oil crops. It also serves as an excellent model system to study polyploidy-related genome evolution because of its paleohexaploid ancestry and its close evolutionary relationships with Arabidopsis thaliana and other Brassica species with larger genomes. Therefore, its genome sequence will be used to accelerate both basic research on genome evolution and applied research across the cultivated Brassica species.Results
We have determined and analyzed the sequence of B. rapa chromosome A3. We obtained 31.9 Mb of sequences, organized into nine contigs, which incorporated 348 overlapping BAC clones. Annotation revealed 7,058 protein-coding genes, with an average gene density of 4.6 kb per gene. Analysis of chromosome collinearity with the A. thaliana genome identified conserved synteny blocks encompassing the whole of the B. rapa chromosome A3 and sections of four A. thaliana chromosomes. The frequency of tandem duplication of genes differed between the conserved genome segments in B. rapa and A. thaliana, indicating differential rates of occurrence/retention of such duplicate copies of genes. Analysis of 'ancestral karyotype' genome building blocks enabled the development of a hypothetical model for the derivation of the B. rapa chromosome A3.Conclusions
We report the near-complete chromosome sequence from a dicotyledonous crop species. This provides an example of the complexity of genome evolution following polyploidy. The high degree of contiguity afforded by the clone-by-clone approach provides a benchmark for the performance of whole genome shotgun approaches presently being applied in B. rapa and other species with complex genomes. 相似文献66.
Poly-L-lysine-induced morphology changes in mixed anionic/zwitterionic and neat zwitterionic-supported phospholipid bilayers
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Poly-L-lysine-induced morphological changes in liquid phase supported bilayers consisting of mixed anionic/zwitterionic and neat zwitterionic headgroup phospholipids were studied with atomic force microscopy and epifluorescence microscopy. Results obtained from these studies indicate that poly-L-lysine can induce domains, defects, and aggregate structures on both mixed bilayers and strictly zwitterionic bilayers. The structures formed on liquid phase supported bilayers were observed to be immobile from a timescale of 50 ms to several minutes. We propose that poly-L-lysine of sufficient length interacts with the mica substrate and phospholipids to create the stationary structures noted. 相似文献
67.
Simon Brooker Archie CA Clements Peter J Hotez Simon I Hay Andrew J Tatem Donald AP Bundy Robert W Snow 《Malaria journal》2006,5(1):1-8
Background
On the island of Bioko (Equatorial Guinea), insecticide-treated nets (ITNs) have been the main tool used to control malaria over the last 13 years. In 2004, started an indoor residual spraying (IRS) campaign to control malaria. The purpose of this study is to asses the impact of the two control strategies on the island of Bioko (Equatorial Guinea), with regards to Plasmodium infection and anaemia in the children under five years of age.Methods
Two transversal studies, the first one prior to the start of the IRS campaign and the second one year later. Sampling was carried out by stratified clusters. Malaria infection was measured by means of thick and thin film, and the packed cell volume (PCV) percentage. Data related to ITN use and information regarding IRS were collected. The Pearson's chi-square and logistic regression statistical tests were used to calculate odds ratios (OR)Results
In the first survey, 168 children were sampled and 433 children in the second one. The prevalence of infection was 40% in 2004, and significantly lower at 21.7% in 2005. PCV was 41% and 39%, respectively. 58% of the children surveyed in 2004 and 44.3% in 2005 had slept under an ITN. 78% of the dwellings studied in 2005 had been sprayed. In the 2005 survey, sleeping without a mosquito net meant a risk of infection 3 times greater than sleeping protected with a net hanged correctly and with no holes (p < 0.05).Conclusion
IRS and ITNs have proven to be effective control strategies on the island of Bioko. The choice of one or other strategy is, above all, a question of operational feasibility and availability of local resources. 相似文献68.
Rebecca E. Haling Matthew K. Tighe Richard J. Flavel Iain M. Young 《Plant and Soil》2013,368(1-2):619-627
Background and aims
Much of our understanding of plant root decomposition and related carbon cycling come from mass loss rates calculated from roots buried in litter bags. However, this may not reflect what actually happens in the soil, where the interactions between root and soil structure presents a more complex physico-chemical environment compared to organic matter isolated in a porous bag buried in disturbed soil. This work investigates the potential of using X-ray micro-computed tomography (CT) to measure root decomposition in situ.Methods
Roots of Vicia faba L. were excised from freshly germinated seeds, buried in re-packed soil cores and cores incubated for 60 days. Changes in root volume and surface area were measured using repeated scans. Additional samples were destructively harvested and roots weighed to correlate root mass with root volume. The method was further applied to an experiment to investigate the effects of soil bulk density and soil moisture on root decomposition.Results
Root volume (X-ray CT) and root mass (destructive harvest) decreased by 90 % over the 60 day incubation period, by which stage, root volume and mass had stabilised. There was a strong correlation (R 2?=?0.97) between root volume and root mass.Conclusions
X-ray CT visualization and analysis provides a unique toolbox to understand root decomposition in situ. 相似文献69.
Audrey Leprince Mark WJ van Passel Vitor AP Martins dos Santos 《Current opinion in biotechnology》2012,23(5):651-658
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70.
Kwon DS Angin M Hongo T Law KM Johnson J Porichis F Hart MG Pavlik DF Tighe DP Kavanagh DG Streeck H Addo MM Kaufmann DE 《Journal of virology》2012,86(12):6586-6594
T cell dysfunction in the presence of ongoing antigen exposure is a cardinal feature of chronic viral infections with persistent high viremia, including HIV-1. Although interleukin-10 (IL-10) has been implicated as an important mediator of this T cell dysfunction, the regulation of IL-10 production in chronic HIV-1 infection remains poorly understood. We demonstrated that IL-10 is elevated in the plasma of individuals with chronic HIV-1 infection and that blockade of IL-10 signaling results in a restoration of HIV-1-specific CD4 T cell proliferation, gamma interferon (IFN-γ) secretion, and, to a lesser extent, IL-2 production. Whereas IL-10 blockade leads to restoration of IFN-γ secretion by HIV-1-specific CD4 T cells in all categories of subjects investigated, significant enhancement of IL-2 production and improved proliferation of CD4 T helper cells are restricted to viremic individuals. In peripheral blood mononuclear cells (PBMCs), this IL-10 is produced primarily by CD14(+) monocytes, but its production is tightly controlled by regulatory T cells (Tregs), which produce little IL-10 directly. When Tregs are depleted from PBMCs of viremic individuals, the effect of the IL-10 signaling blockade is abolished and IL-10 production by monocytes decreases, while the production of proinflammatory cytokines, such as tumor necrosis factor alpha (TNF-α), increases. The regulation of IL-10 by Tregs appears to be mediated primarily by contact or paracrine-dependent mechanisms which involve IL-27. This work describes a novel mechanism by which regulatory T cells control IL-10 production and contribute to dysfunctional HIV-1-specific CD4 T cell help in chronic HIV-1 infection and provides a unique mechanistic insight into the role of regulatory T cells in immune exhaustion. 相似文献