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31.
Hein I Klinger S Dooms M Flekna G Stessl B Leclercq A Hill C Allerberger F Wagner M 《Applied and environmental microbiology》2011,77(6):2169-2173
Listeria monocytogenes strains (n = 117) were screened for the presence of stress survival islet 1 (SSI-1). SSI-1(+) strains (32.5%) belonged mainly to serotypes 1/2c, 3b, and 3c. All sequence type 121 (ST-121) strains included (n = 7) possessed homologues to Listeria innocua genes lin0464 and lin0465 instead of SSI-1. 相似文献
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Peeters RP van den Beld AW Attalki H Toor Hv de Rijke YB Kuiper GG Lamberts SW Janssen JA Uitterlinden AG Visser TJ 《American journal of physiology. Endocrinology and metabolism》2005,289(1):E75-E81
Type II deiodinase (D2) is important in the regulation of local thyroid hormone bioactivity in certain tissues. D2 in skeletal muscle may also play a role in serum triiodothyronine (T(3)) production. In this study, we identified a polymorphism in the 5'-UTR of the D2 gene (D2-ORFa-Gly3Asp). We investigated the association of D2-ORFa-Gly3Asp, and of the previously identified D2-Thr92Ala polymorphism, with serum iodothyronine levels. D2-ORFa-Gly3Asp was identified by sequencing the 5'-UTR of 15 randomly selected individuals. Genotypes for D2-ORFa-Gly3Asp were determined in 156 healthy blood donors (age 46.3 +/- 12.2 yr) and 349 ambulant elderly men (age 77.7 +/- 3.5 yr) and related to serum iodothyronine and TSH levels. D2-ORFa-Asp(3) had an allele frequency of 33.9% in blood bank donors and was associated with serum thyroxine (T(4); Gly/Gly vs. Gly/Asp vs. Asp/Asp = 7.06 +/- 0.14 vs. 6.74 +/- 0.15 vs. 6.29 +/- 0.27 microg/dl, P = 0.01), free T(4) (1.22 +/- 0.02 vs. 1.16 +/- 0.02 vs. 1.06 +/- 0.04 ng/dl, P = 0.001), reverse T(3) (P = 0.01), and T(3)/T(4) ratio (P = 0.002) in a dose-dependent manner, but not with serum T(3) (P = 0.59). In elderly men, D2-ORFa-Asp(3) had a similar frequency but was not associated with serum iodothyronine levels. This new polymorphism in the 5'-UTR of D2 is associated with iodothyronine levels in blood donors but not in elderly men. We hypothesize that this might be explained by the decline in skeletal muscle size during aging, resulting in a relative decrease in the contribution of D2 to serum T(3) production. 相似文献
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Matthew A.J. Duncton Eugene L. Piatnitski Chekler Reeti Katoch-Rouse Dan Sherman Wai C. Wong Leon M. Smith Joel K. Kawakami Alexander S. Kiselyov Daniel L. Milligan Chris Balagtas Yaron R. Hadari Ying Wang Sheetal N. Patel Robin L. Rolster James R. Tonra David Surguladze Stan Mitelman Paul Kussie Peter Bohlen Jacqueline F. Doody 《Bioorganic & medicinal chemistry》2009,17(2):731-740
A series of arylphthalazine derivatives were synthesized and evaluated as antagonists of VEGF receptor II (VEGFR-2). IM-094482 57, which was prepared in two steps from commercially available starting materials, was found to be a potent inhibitor of VEGFR-2 in enzymatic, cellular and mitogenic assays (comparable activity to ZD-6474). Additionally, 57 inhibited the related receptor, VEGF receptor I (VEGFR-1), and showed excellent exposure when dosed orally to female CD-1 mice. 相似文献
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Elise Courtot Claude L. Charvet Robin N. Beech Abdallah Harmache Adrian J. Wolstenholme Lindy Holden-Dye Vincent O’Connor Nicolas Peineau Debra J. Woods Cedric Neveu 《PLoS pathogens》2015,11(12)
Acetylcholine receptors are pentameric ligand–gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Interestingly, parasitic nematodes affecting human or animal health possess two closely related members of this gene family, acr-26 and acr-27 that are essentially absent in free-living or plant parasitic species. Using the pathogenic parasitic nematode of ruminants, Haemonchus contortus, as a model, we found that Hco-ACR-26 and Hco-ACR-27 are co-expressed in body muscle cells. We demonstrated that co-expression of Hco-ACR-26 and Hco-ACR-27 in Xenopus laevis oocytes led to the functional expression of an acetylcholine-receptor highly sensitive to the anthelmintics morantel and pyrantel. Importantly we also reported that ACR-26 and ACR-27, from the distantly related parasitic nematode of horses, Parascaris equorum, also formed a functional acetylcholine-receptor highly sensitive to these two drugs. In Caenorhabditis elegans, a free-living model nematode, we demonstrated that heterologous expression of the H. contortus and P. equorum receptors drastically increased its sensitivity to morantel and pyrantel, mirroring the pharmacological properties observed in Xenopus oocytes. Our results are the first to describe significant molecular determinants of a novel class of nematode body wall muscle AChR. 相似文献
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In response to ever-increasing anthropogenic changes to natural ecosystems, regional, national and international organizations have established guidelines for monitoring biological diversity. Most monitoring programs, however, do not take full advantage of the potential afforded by molecular genetic markers, which can provide information relevant to both ecological and evolutionary time frames, while costing less and being more sensitive and reliable than traditional monitoring approaches. As several molecular and computational approaches are relatively new, many technical and theoretical issues remain to be resolved. Here, we illustrate how DNA and population genetic data can provide valuable information, often unattainable via other approaches, for monitoring species of management, conservation and ecological interest. 相似文献
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Norman Dandy Stephanie Ballantyne Darren Moseley Robin Gill Christopher Quine René Van Der Wal 《European Journal of Wildlife Research》2012,58(4):695-706
Wildlife management methods such as culling (lethal control) and fencing can be controversial in some circumstances. Such controversy can be problematic for decision-makers or those managing decision-making processes and can lead to management delays or inertia. Understanding the reasons why people support or oppose specific management methods is therefore an important objective for researchers. Attitudes towards methods are in part based on individual beliefs about those methods, the species of wildlife being managed and other associated phenomena. This paper adopts a qualitative approach to develop understanding of these beliefs. We conducted 17 focus-groups on wild deer management at two locations in Britain, with both ‘professional’ land manager and ‘public’ participants (n?=?103). We identified a number of individual beliefs which are grouped into five categories: naturalness, overabundance, impacts, effectiveness and animal welfare. Our findings suggest that potentially controversial management methods will receive most support where the objective is to maintain a ‘natural’ environment, at sites where impacts are evident, and when using targeted and effective methods. 相似文献
40.
Structure of the intergenic spacer region from the ribosomal RNA gene family of white spruce (Picea glauca) 总被引:2,自引:0,他引:2
Five genomic clones containing ribosomal DNA repeats from the gymnosperm white spruce (Picea glauca) have been isolated and characterized by restriction enzyme analysis. No nucleotide variation or length variation was detected within the region encoding the ribosomal RNAs. Four clones which contained the intergenic spacer (IGS) region from different rDNA repeats were further characterized to reveal the sub-repeat structure within the IGS. The sub-repeats were unusually long, ranging from 540 to 990 bp but in all other respects the structure of the IGS was very similar to the organization of the IGS from wheat, Drosophila and Xenopus. 相似文献