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排序方式: 共有427条查询结果,搜索用时 78 毫秒
421.
Paola Cristina Resende Fernando Couto Motta/+ Priscila Silva Born Milene Miranda Marilda M Siqueira 《Memórias do Instituto Oswaldo Cruz》2015,110(1):148-150
The influenza A(H3N2) virus has circulated worldwide for almost five decades and is
the dominant subtype in most seasonal influenza epidemics, as occurred in the 2014
season in South America. In this study we evaluate five whole genome sequences of
influenza A(H3N2) viruses detected in patients with mild illness collected from
January-March 2014. To sequence the genomes, a new generation sequencing (NGS)
protocol was performed using the Ion Torrent PGM platform. In addition to analysing
the common genes, haemagglutinin, neuraminidase and matrix, our work also comprised
internal genes. This was the first report of a whole genome analysis with Brazilian
influenza A(H3N2) samples. Considerable amino acid variability was encountered in all
gene segments, demonstrating the importance of studying the internal genes. NGS of
whole genomes in this study will facilitate deeper virus characterisation,
contributing to the improvement of influenza strain surveillance in Brazil. 相似文献
422.
Summary A glasshouse experiment was conducted to determine how reduction conditions would affect plant nutrient availability and uptake in a red-yellow latosol (Acrustox). Soil analysis showed that the most important changes were a marked increase in extractable iron and an inhibition of nitrification. The grass andropogon (Andropogon gayanus Kunth var.bisquamulatus (Hoechst) Hack) and the legume stylo (Stylosanthes capitata (Vog)) responded differently to reducing conditions.Andropogon showed low P, Ca, Mg, Fe and Mn content in the shoots but an intense coating of oxidized iron was observed on the surface of roots. Stylo plants, on the other hand, showed no iron deposition on the root surfaces but a high iron content in the shoots. No decreased P, Ca or Mg content was observed in this case. It was concluded that in water saturated soil, reduction took place and plant performance was affected not only by restricted root development but by preventing P, Ca and Mg uptake in andropogon and increasing Fe uptake in stylo plants. It is suggested that restricted P, Ca and Mg uptake by andropogen would be the result of iron deposition on root surfaces. 相似文献
423.
The molecular organization of the beta-globin complex of the deer mouse, Peromyscus maniculatus 总被引:1,自引:0,他引:1
Padgett RW; Loeb DD; Snyder LR; Edgell MH; Hutchison CA d 《Molecular biology and evolution》1987,4(1):30-45
Recombinant DNA clones have been isolated that contain 80 kb of the
beta-globin complex from the deer mouse, Peromyscus maniculatus.
Comparisons of this complex with that from the laboratory mouse, Mus
domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3,
Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin
complex since the two species diverged. Unlike other mammals studied thus
far, the deer mouse possesses three adult genes. Partial sequence analysis
indicates that each of the three adult genes is intact and hence may be
functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to
genomic blots from Peromyscus reveals that it has a homologous counterpart
in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO
and Hbb-bhl, are also found in Peromyscus. The strong hybridization between
the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO
genes suggest that both pairs are important for the ontogeny of these mice
although no known product has been identified for the Hbb-bhO genes. The
presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication
that created this related gene set occurred before the two lineages
diverged. A single gene for Hbb-y has been isolated from Peromyscus. The
adult region in Peromyscus has undergone significant divergence from the
same region in Mus, having three rather than two adult genes, the
acquisition of at least 15 kb of extra DNA relative to Mus, and possibly
the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in
contrast, contains the same set of genes apparently distributed over the
same amount of DNA as in the Mus beta- globin complex. This observation
suggests that the embryonic region of the complex is more evolutionarily
stable than the adult region.
相似文献
424.
Mundy, P.J. & Couto, J.T. 2000. High productivity by Fish Eagles on a polluted dam near Harare. Ostrich 71 (1 & 2): 11–14. Lake Chivero, in the Robert McIlwaine Recreational Park west of Harare, is the capital city's main reservoir of drinking water. It has been the subject of five surveys for pesticides and/or heavy metals in the period 1974–1995. The (geometric) average DDE residue level in seven Fish Eagle eggs collected in 1980 was 53 ppm dry weight. By 1995, DDT levels had considerably declined. There are now five pairs of Fish Eagles on Lake Chivero (1996), at a very low density of 14.8 km shoreline per pair. In the 14-year period, 1984–1997, 40 pair-occupations have been found and inspected, which produced 64 fledglings. One nest had fledglings in 11 years, and on three occasions broods of three were produced from it. A fourth brood of three was produced at another nest. The dam receives treated sewage effluent from the city and is now highly eutrophic; this has contributed to the eagles' breeding performance. 相似文献
425.
Paul R. De Lay Adle Benzaken Quarraisha Abdool Karim Sani Aliyu Carolyn Amole George Ayala Kalipso Chalkidou Judy Chang Michaela Clayton Aleny Couto Carl Dieffenbach Mark Dybul Wafaa El Sadr Marelize Gorgens Daniel Low-Beer Smail Mesbah Jorge Saveedra Petchsri Sirinirund John Stover Omar Syarif Aditia Taslim Safiatou Thiam Lucy Wanjiku Njenga Peter D. Ghys Jose Antonio Izazola-Licea Luisa Frescura Erik Lamontagne Peter Godfrey-Faussett Christopher Fontaine Iris Semini Shannon Hader 《PLoS medicine》2021,18(6)
Paul De Lay and co-authors introduce a Collection on the design of targets for ending the AIDS epidemic. 相似文献
426.
Natália Coelho Couto de Azevedo Fernandes Paloma Martins do Nascimento Angélica M. Sánchez-Sarmiento Rodrigo A. Ressio Cinthya dos Santos Cirqueira Cristina Takami Kanamura Júlia de Carvalho Silvana Mello Pereira da Silva Amanda Rezende Peruchi Julio César de Souza Junior Zelinda Maria Braga Hirano José Luiz Catão-Dias 《Journal of medical primatology》2020,49(2):65-70
427.
Dayvid R. Couto Stefan Porembski Wilhelm Barthlott Luiza F. A. de Paula 《Austral ecology》2023,48(6):1074-1082
Vascular epiphytes are a characteristic life form in many tropical regions and often occur growing on bare rocks. South America has the highest diversity. Here, we describe a neglected life form: hyperepilithics adapted and restricted to growing on vertical (inclination above 70°) and bare rock walls without having roots intruding the substrate. Hyperepilithics are in particular present on Brazilian inselbergs and dominated by highly specialized Bromeliaceae, mainly of the genera Stigmatodon, Tillandsia and Alcantarea, whereas Orchidaceae surprisingly has a low representation. An overview of this habitat, the life form hyperepilithics and a comparison with similar paleotropical habitats (mainly inselbergs in Western/Eastern Africa and India) are provided. Attention is drawn to hyperepilithics as a most promising and not yet exploited source for a sustainable urban ‘vertical gardening’, for example in tropical megacities. 相似文献