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排序方式: 共有331条查询结果,搜索用时 15 毫秒
321.
Andrea Egizi Leslie Bulaga‐Seraphin Erika Alt Waheed I. Bajwa Joshua Bernick Matthew Bickerton Scott R. Campbell Neeta Connally Kandai Doi Richard C. Falco David N. Gaines Telleasha L. Greay Vanessa L. Harper Allen C.G. Heath Ju Jiang Terry A. Klein Lauren Maestas Thomas N. Mather James L. Occi Charlotte L. Oskam Jennifer Pendleton Marissa Teator Alec T. Thompson Danielle M. Tufts Rika Umemiya‐Shirafuji Meredith C. VanAcker Michael J. Yabsley Dina M. Fonseca 《Zoonoses and public health》2020,67(6):637-650
Established populations of Asian longhorned ticks (ALT), Haemaphysalis longicornis, were first identified in the United States (US) in 2017 by sequencing the mitochondrial cytochrome c oxidase subunit I (cox1) ‘barcoding’ locus followed by morphological confirmation. Subsequent investigations detected ALT infestations in 12, mostly eastern, US states. To gain information on the origin and spread of US ALT, we (1) sequenced cox1 from ALT populations across 9 US states and (2) obtained cox1 sequences from potential source populations [China, Japan and Republic of Korea (ROK) as well as Australia, New Zealand and the Kingdom of Tonga (KOT)] both by sequencing and by downloading publicly available sequences in NCBI GenBank. Additionally, we conducted epidemiological investigations of properties near its initial detection locale in Hunterdon County, NJ, as well as a broader risk analysis for importation of ectoparasites into the area. In eastern Asian populations (China/Japan/ROK), we detected 35 cox1 haplotypes that neatly clustered into two clades with known bisexual versus parthenogenetic phenotypes. In Australia/New Zealand/KOT, we detected 10 cox1 haplotypes all falling within the parthenogenetic cluster. In the United States, we detected three differentially distributed cox1 haplotypes from the parthenogenetic cluster, supporting phenotypic evidence that US ALT are parthenogenetic. While none of the source populations examined had all three US cox1 haplotypes, a phylogeographic network analysis supports a northeast Asian source for the US populations. Within the United States, epidemiological investigations indicate ALT can be moved long distances by human transport of animals, such as horses and dogs, with smaller scale movements on wildlife. These results have relevant implications for efforts aimed at minimizing the spread of ALT in the United States and preventing additional exotic tick introductions. 相似文献
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323.
Eranga K. Galappaththi Vasantha B. Susarla Samantha J. T. Loutet Stephanie T. Ichien Amanda A. Hyman James D. Ford 《Fish and Fisheries》2022,23(1):4-21
We conducted a global systematic literature review of climate change adaptation in fisheries. We addressed three specific questions: (i) What are fisheries adapting to? (ii) How are fisheries adapting? and (iii) What research gaps need to be addressed? We identified, characterized and examined case studies published between 1990 and 2019 that lie at the intersection of the domains of climate change, adaptation and fisheries. We characterized the documented climate change effects in fisheries that are being adapted to multiple stressors, general climate impacts, extreme events, ocean conditions, marine system shifts, climate variability, fishery dynamics, species distribution and atmospheric warming. Three categories of adaptive responses came to light: coping mechanisms (e.g. changing fishing location, use of traditional knowledge); adaptive strategies (e.g. livelihood diversification, incorporation of technology); and management responses (e.g. adaptive management, adaptation planning). We identified key potential areas for future research, including studies on the limits and barriers for adaptation, studies using specific conceptual and methodological approaches, and studies focussing on the top-producing countries such as China, Indonesia, Peru and Russia. This analysis gives broader insights to the fisheries industry and to climate change adaptation research to proceed in the face of new global challenges. 相似文献
324.
Joye SB Leifer I MacDonald IR Chanton JP Meile CD Teske AP Kostka JE Chistoserdova L Coffin R Hollander D Kastner M Montoya JP Rehder G Solomon E Treude T Villareal TA 《Science (New York, N.Y.)》2011,332(6033):1033; author reply 1033
Kessler et al. (Reports, 21 January 2011, p. 312) reported that methane released from the 2010 Deepwater Horizon blowout, approximately 40% of the total hydrocarbon discharge, was consumed quantitatively by methanotrophic bacteria in Gulf of Mexico deep waters over a 4-month period. We find the evidence explicitly linking observed oxygen anomalies to methane consumption ambiguous and extension of these observations to hydrate-derived methane climate forcing premature. 相似文献
325.
Assistance of microbial glycolipid antigen processing by CD1e 总被引:1,自引:0,他引:1
de la Salle H Mariotti S Angenieux C Gilleron M Garcia-Alles LF Malm D Berg T Paoletti S Maître B Mourey L Salamero J Cazenave JP Hanau D Mori L Puzo G De Libero G 《Science (New York, N.Y.)》2005,310(5752):1321-1324
Complexes between CD1 molecules and self or microbial glycolipids represent important immunogenic ligands for specific subsets of T cells. However, the function of one of the CD1 family members, CD1e, has yet to be determined. Here, we show that the mycobacterial antigens hexamannosylated phosphatidyl-myo-inositols (PIM6) stimulate CD1b-restricted T cells only after partial digestion of the oligomannose moiety by lysosomal alpha-mannosidase and that soluble CD1e is required for this processing. Furthermore, recombinant CD1e was able to bind glycolipids and assist in the digestion of PIM6. We propose that, through this form of glycolipid editing, CD1e helps expand the repertoire of glycolipidic T cell antigens to optimize antimicrobial immune responses. 相似文献
326.
327.
Wang W Black SS Edwards MD Miller S Morrison EL Bartlett W Dong C Naismith JH Booth IR 《Science (New York, N.Y.)》2008,321(5893):1179-1183
How ion channels are gated to regulate ion flux in and out of cells is the subject of intense interest. The Escherichia coli mechanosensitive channel, MscS, opens to allow rapid ion efflux, relieving the turgor pressure that would otherwise destroy the cell. We present a 3.45 angstrom-resolution structure for the MscS channel in an open conformation. This structure has a pore diameter of approximately 13 angstroms created by substantial rotational rearrangement of the three transmembrane helices. The structure suggests a molecular mechanism that underlies MscS gating and its decay of conductivity during prolonged activation. Support for this mechanism is provided by single-channel analysis of mutants with altered gating characteristics. 相似文献
328.
Samantha L. Eaton Mary-Jo Anderson Scott Hamilton Lorenzo Gonzlez Jill Sales Martin Jeffrey Hugh W. Reid Mara S. Rocchi Francesca Chianini 《Veterinary immunology and immunopathology》2009,131(1-2):105-109
In order to gain a better understanding of the pathogenesis of scrapie in sheep an experimental model was developed to characterise immune system cells in the minutes following inoculation with scrapie-brain homogenate. Four 1-year-old susceptible (ARQ/ARQ) sheep were inoculated via the subcutaneous route at four different peripheral lymph node (LNs) drainage sites, at specific time points, prior to euthanasia of the sheep. The LNs were removed post-mortem at 30, 90, 180 and 300 min after inoculation. Flow cytometric triple-labelling was carried out on the LN cells and indicated that inoculation of scrapie-brain homogenate adjacent to a lymph node may delay or even inhibit the number of host CD21+ B cells expressed within the first 5 h. Immunohistochemistry was used to attempt detection of the abnormal form of prion protein (PrPsc) in draining LNs adjacent to inoculation sites, with negative results at those time points. 相似文献
329.
330.
Lisa S Kirkland Evatt Chirgwin Samantha E Ward Benjamin S Congdon Anthony van Rooyen Paul A Umina 《Pest management science》2023,79(5):1851-1859