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31.
Summary Mice inoculated withPlasmodium berghei developed a drastic and significant pulmonary edema. Treatment of animals with phenoxybenzamine rendered mice hyporeactive to this physiopathological alteration.This work was supported by a grant aided by «Conselho Nacional de Desenvolvimento Científico e Tecnológico» (CNPq, Brasil). Presented in preliminary form at the XIX Annual Meeting of the Brazilian Society of Tropical Medicine, Rio de Janeiro, R. J., February 20, 1983.Acknowledgments. We thank Mr Antonio Fernando de P. Oliveira and Solano S. Martins for their excellent technical help.  相似文献   
32.
Transcriptome analysis of the acoelomate human parasite Schistosoma mansoni   总被引:1,自引:0,他引:1  
Schistosoma mansoni is the primary causative agent of schistosomiasis, which affects 200 million individuals in 74 countries. We generated 163,000 expressed-sequence tags (ESTs) from normalized cDNA libraries from six selected developmental stages of the parasite, resulting in 31,000 assembled sequences and 92% sampling of an estimated 14,000 gene complement. By analyzing automated Gene Ontology assignments, we provide a detailed view of important S. mansoni biological systems, including characterization of metazoa-specific and eukarya-conserved genes. Phylogenetic analysis suggests an early divergence from other metazoa. The data set provides insights into the molecular mechanisms of tissue organization, development, signaling, sexual dimorphism, host interactions and immune evasion and identifies novel proteins to be investigated as vaccine candidates and potential drug targets.  相似文献   
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Separability of clusters is an issue that arises in many different areas, and is often used in a rather vague and subjective manner. We introduce a combinatorial notion of interiority to derive a global view on separability of a set of entities. We develop this approach further to evaluate the overall separability of a partition in the context of cluster analysis. Our approach captures combinatorial and geometrical aspects of data and provides, in addition to numerical evaluations, graphical representations particularly useful when data are not easily visualized. We illustrate the methodology on some real and simulated datasets.  相似文献   
35.
Naturally occurring variation in gene copy number is increasingly recognized as a heritable source of susceptibility to genetically complex diseases. Here we report strong association between FCGR3B copy number and risk of systemic lupus erythematosus (P = 2.7 x 10(-8)), microscopic polyangiitis (P = 2.9 x 10(-4)) and Wegener's granulomatosis in two independent cohorts from the UK (P = 3 x 10(-3)) and France (P = 1.1 x 10(-4)). We did not observe this association in the organ-specific Graves' disease or Addison's disease. Our findings suggest that low FCGR3B copy number, and in particular complete FCGR3B deficiency, has a key role in the development of systemic autoimmunity.  相似文献   
36.
The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ~4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ~60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease.  相似文献   
37.
Biochar trials aim to enrich soil for smallholders   总被引:2,自引:0,他引:2  
Woods WI  Falcão NP  Teixeira WG 《Nature》2006,443(7108):144
  相似文献   
38.
Mice inoculated with Plasmodium berghei developed a drastic and significant pulmonary edema. Treatment of animals with phenoxybenzamine rendered mice hyporeactive to this physiopathological alteration.  相似文献   
39.
This paper aims to describe the application of Soft Systems Methodology (SSM) to the reality of a Brazilian enterprise. Systemic practices are ways of putting to use systemic thought in the real world, using the precepts of the systemic approach, which is very important for knowledge management and globalization. The systemic practice SSM is used in the resolution of ill-defined problems, which often involve behavioral variables and, thus, cannot be addressed by the so-called hard methodologies. In this paper, SSM is applied to the problematic of a middle-market business, an auto supply distributor, whose managers consulted the authors of this paper as regards proposing improvements of its performance. As a result of this work, the authors were able to propose core changes in attitudes, leading to changes in structure and process.  相似文献   
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