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21.
A forecast of nonepidemic morbidity due to acute respiratory infections were carry out by using time series analysis. The data consisted of the weekly reports of medical patient consultation from ambulatory facilities from the whole country. A version of regression model was fitted to the data. Using this approach, we were able to detect the starting data of the epidemic under routine surveillance conditions for various age groups. It will be necessary to improve the data reporting system in order to introduce these procedures at the local health center level, as well as on the provincial level. 相似文献
22.
Evolutionary relationships within the fungi: analyses of nuclear small subunit rRNA sequences. 总被引:25,自引:0,他引:25
T D Bruns R Vilgalys S M Barns D Gonzalez D S Hibbett D J Lane L Simon S Stickel T M Szaro W G Weisburg 《Molecular phylogenetics and evolution》1992,1(3):231-241
Nucleotide sequences of the small subunit ribosomal RNA (18S) gene were used to investigate evolutionary relationships within the Fungi. The inferred tree topologies are in general agreement with traditional classifications in the following ways: (1) the Chytridiomycota and Zygomycota appear to be basal groups within the Fungi. (2) The Ascomycota and Basidiomycota are a derived monophyletic group. (3) Relationships within the Ascomycota are concordant with traditional orders and divide the hemi- and euascomycetes into distinct lineages. (4) The Basidiomycota is divided between the holobasidiomycetes and phragmobasidiomycetes. Conflicts with traditional classification were limited to weakly supported branches of the tree. Strongly supported relationships were robust to minor changes in alignment, method of analysis, and various weighting schemes. Weighting, either of transversions or by site, did not convincingly improve the status of poorly supported portions of the tree. The rate of variation at particular sites does not appear to be independent of lineage, suggesting that covariation of sites may be an important phenomenon in these genes. 相似文献
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An insulinlike peptide (ILAs) has been isolated in our laboratory from human serum. The binding of 123I-labeled ILAs was studied in subcellular fractions from rat liver and found to be much greater in microsomes than purified plasmalemma. The high level of microsomal binding was due to a particular enrichment of binding sites in Golgi elements. Binding to Golgi was time and temperature dependent and was augmented by an increase of either subcellular fraction or 125I-labeled ILAs in accordance with a mass action process. Degradation of 125I-labeled ILAs was greatest in the Golgi vesicle fraction and was reduced by incubation at 4 degrees C. Bound 125I-labeled ILAs could be eluted and was found to retain integrity. Binding was pH dependent with a broad optimum at pH 7.7-8.5. Dissociation of bound 125I-labeled ILAs was time and temperature dependent. It was greater at 37 than 4 degrees C, and was uninfluenced by unlabeled ILAs. The ILAs receptor was stable at 4 degrees C but was markedly decreased by preincubation at 37 degrees C. The binding of 125I-labeled ILAs was inhibited by unlabeled ILAs and related insulinlike peptides (the insulinlike growth factors, IGF-1 and IGF-2) in a dose-dependent manner. Insulin and its analogues had only a partially inhibitory effect, and structurally unrelated peptides were without inhibitory efficacy. In contrast ILAs and IGF-1 and IGF-2 inhibited 125I-labeled insulin binding to its receptors in a dose-dependent fashion. These observations identify a receptor for insulinlike peptides in the Golgi elements of rat liver. It is distinct from the insulin receptor previously observed in these elements. The dual interaction of ILAs and other insulinlike peptides with both the insulin receptor and their own unique receptor constitutes the presumed biochemical basis for the two types of action effected by this family of peptides, namely, an effect on metabolism comparable to insulin and an effect on cellular anabolism and growth. 相似文献
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The airways of people with cystic fibrosis (CF) often harbour diverse polymicrobial communities. These airway infections can be impossible to resolve through antibiotic intervention, even though isolates of the individual species present are susceptible to the treatment when tested in vitro. In this work, we investigate how polymicrobial cultures comprised of key CF-associated pathogens respond to challenge with species-specific antimicrobial agents; colistin (targets Pseudomonas aeruginosa), fusidic acid (targets Staphylococcus aureus), and fluconazole (targets Candida albicans). We found that growth in a polymicrobial environment protects the target microorganism (sometimes by several orders of magnitude) from the effect(s) of the antimicrobial agent. This decreased antimicrobial efficacy was found to have both non-heritable (physiological) and heritable (genetic) components. Whole-genome sequencing of the colistin-resistant P. aeruginosa isolates revealed single nucleotide polymorphisms and indels in genes encoding lipopolysaccharide (LPS) biosynthesis and/or pilus biogenesis, indicating that a previously undescribed colistin resistance mechanism was in operation. This was subsequently confirmed through further genetic analyses. Our findings indicate that the polymicrobial nature of the CF airways is likely to have a significant impact on the clinical response to antimicrobial therapy.Subject terms: Clinical microbiology, Antibiotics 相似文献
29.
Proteomic analysis of microvesicles from plasma of healthy donors reveals high individual variability 总被引:1,自引:0,他引:1
Bastos-Amador P Royo F Gonzalez E Conde-Vancells J Palomo-Diez L Borras FE Falcon-Perez JM 《Journal of Proteomics》2012,75(12):3574-3584
Healthy blood plasma is required for several therapeutic procedures. To maximize successful therapeutic outcomes it is critical to control the quality of blood plasma. Clearly initiatives to improve the safety of blood transfusions will have a high economical and social impact. A detailed knowledge of the composition of healthy blood plasma is essential to facilitate such improvements. Apart from free proteins, lipids and metabolites, blood plasma also contains cell-derived microvesicles, including exosomes and microparticles from several different cellular origins. In this study, we have purified microvesicles smaller than 220nm from plasma of healthy donors and performed proteomic, ultra-structural, biochemical and functional analyses. We have detected 161 microvesicle-associated proteins, including many associated with the complement and coagulation signal-transduction cascades. Several proteases and protease inhibitors associated with acute phase responses were present, indicating that these microvesicles may be involved in these processes. There was a remarkably high variability in the protein content of plasma from different donors. In addition, we report that this variability could be relevant for their interaction with cellular systems. This work provides valuable information on plasma microvesicles and a foundation to understand microvesicle biology and clinical implications. 相似文献
30.
Yan?Pu Trevor?Treasure Ronalds?Gonzalez Richard?A.?VendittiEmail author Hasan?Jameel 《Bioenergy Research》2013,6(3):1094-1103
Autohydrolysis is a hot water pretreatment to extract soluble components from wood that can be used prior to converting the woody residuals into paper, wood products, fuel, or other goods. In this study, mixed softwood chips were autohydrolyzed in hot water at 150, 160, 170, and 180 °C for 1 and 2 h residence times. The objective was to understand the tradeoff between the extraction of fermentable sugar and the residual solid total energy of combustion quantitatively. This process strategy will be referred to as “value prior to combustion”. High-performance liquid chromatography was used to determine chemical compositions (sugars and byproducts such as acetic acid, furfural, and hydroxymethylfurfural) of the extracted liquid and residuals; a bomb calorimeter was used to measure the heating value of original wood and solid residue. As the autohydrolysis temperature increased, material balances of the system indicated higher volatile byproducts loss. More hemicelluloses were solubilized by the hot water extraction process at higher temperatures and longer residence times, and a greater degree of sugar degradation was also observed. The maximum sugar yield was determined to occur at conditions of 170 °C for 2 h, during which 13 g of sugar was recovered from the extract out of 100 g of oven-dried wood. The heating value of the solid residues after extraction was greater than the original wood. The total energy content of the solid residual after extraction ranged from 85 to 98 % of the original energy content of the feed with higher temperatures reducing the total energy content. 相似文献