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301.
Jiménez RP Pupo AE Cabrales JM Joa JA Cabrales LE Nava JJ Aguilera AR Mateus MA Jarque MV Brooks SC 《Bioelectromagnetics》2011,32(2):120-130
Electrotherapy with direct current delivered through implanted electrodes is used for local control of solid tumors in both preclinical and clinical studies. The aim of this research is to develop a solution method for obtaining a three-dimensional analytical expression for potential and electric current density as functions of direct electric current intensity, differences in conductivities between the tumor and the surrounding healthy tissue, and length, number and polarity of electrodes. The influence of these parameters on electric current density in both media is analyzed. The results show that the electric current density in the tumor is higher than that in the surrounding healthy tissue for any value of these parameters. The conclusion is that the solution method presented in this study is of practical interest because it provides, in a few minutes, a convenient way to visualize in 3D the electric current densities generated by a radial electrode array by means of the adequate selection of direct current intensity, length, number, and polarity of electrodes, and the difference in conductivity between the solid tumor and its surrounding healthy tissue. 相似文献
302.
303.
María Isabel Gómez Jiménez Carlos E. Sarmiento María Fernanda Díaz Alexander Chautá Andrés Peraza Augusto Ramírez Katja Poveda 《Entomologia Experimentalis et Applicata》2014,153(1):24-33
It is expected that females preferentially oviposit on plant hosts that allow for optimal larval performance. However, this expectation contradicts empirical evidence where adults do not always choose the best host for their descendants. Recent evidence suggests that females’ host selection depends on the number of potential hosts. Females from oligophagous species seem to be able to choose an appropriate host in terms of larval performance, whereas in polyphagous species, adult oviposition preference is not related with larval performance. This suggests that larvae in polyphagous species could be taking a more active role in host selection than their mothers. Here, we evaluated the oviposition preference and the larval preference and performance of two polyphagous species of economic importance, Copitarsia decolora (Guenée) (Lepidoptera: Noctuidae: Cuculliinae) and Peridroma saucia (Hübner) (Lepidoptera: Noctuidae: Noctuinae), on eight species of cultivated plants. In laboratory and greenhouse choice assays, we tested adult preference for oviposition and larval preference at 1 and 24 h. Larval performance was measured in terms of survival to adulthood, length of larval period, and pupal weight. We found that both adult females and larvae actively choose their hosts and that the larval preference toward the hosts is related to the females’ preference in both herbivore species. However, the females and larvae did not preferentially select the host with the best larval performance, indicating that larval performance is not related to female or larval preference and that other selective pressures are influencing the choice of the host plant in these two species. 相似文献
304.
Dele Ogunremi John Devenish Kingsley Amoako Hilary Kelly Andrée Ann Dupras Sebastien Belanger Lin Ru Wang 《BMC genomics》2014,15(1)
Background
There is a need to characterize genomes of the foodborne pathogen, Salmonella enterica serovar Enteritidis (SE) and identify genetic information that could be ultimately deployed for differentiating strains of the organism, a need that is yet to be addressed mainly because of the high degree of clonality of the organism. In an effort to achieve the first characterization of the genomes of SE of Canadian origin, we carried out massively parallel sequencing of the nucleotide sequence of 11 SE isolates obtained from poultry production environments (n = 9), a clam and a chicken, assembled finished genomes and investigated diversity of the SE genome.Results
The median genome size was 4,678,683 bp. A total of 4,833 chromosomal genes defined the pan genome of our field SE isolates consisting of 4,600 genes present in all the genomes, i.e., core genome, and 233 genes absent in at least one genome (accessory genome). Genome diversity was demonstrable by the presence of 1,360 loci showing single nucleotide polymorphism (SNP) in the core genome which was used to portray the genetic distances by means of a phylogenetic tree for the SE isolates. The accessory genome consisted mostly of previously identified SE prophage sequences as well as two, apparently full- sized, novel prophages namely a 28 kb sequence provisionally designated as SE-OLF-10058 (3) prophage and a 43 kb sequence provisionally designated as SE-OLF-10012 prophage.Conclusions
The number of SNPs identified in the relatively large core genome of SE is a reflection of substantial diversity that could be exploited for strain differentiation as shown by the development of an informative phylogenetic tree. Prophage sequences can also be exploited for SE strain differentiation and lineage tracking. This work has laid the ground work for further studies to develop a readily adoptable laboratory test for the subtyping of SE.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-713) contains supplementary material, which is available to authorized users. 相似文献305.
The mating pattern and female fertility on the two main mitochondrial DNA haplotypes (I and II) of Drosophila subobscura were studied, in an attempt to find possible differences between them in relation to sexual selection or isolation that could explain the populational dynamics and the co-existence of these two strains in nature. The mating pattern indicated an assortative mating in population cages, where couples of the same haplotype, mainly those of haplotype I, mated more often. However, the significations detected in laboratory conditions disappeared in wild populations, where random mating was the rule. The female fertility also showed differences in the laboratory compared to the wild, since couples with haplotype I males were more efficient in the laboratory populations. These results, together with others that we previously obtained, either point to selection acting directly on the mtDNA or to the presence of some kind of cytonuclear co-adaptation in these two haplotypes, although this must be modulated by other factors that change with the seasons and time. The end result could well be a balance of opposite forces acting on both haplotypes. 相似文献
306.
Pinheiro Kelly V. Thomaz Amanda Souza Bárbara Kunzler Metcalfe Victoria Anne Freire Natália Hogetop Brunetto André Tesainer de Farias Caroline Brunetto Jaeger Mariane Bambini Victorio Smith Christopher G. S. Shaw Lisa Roesler Rafael 《Molecular biology reports》2020,47(9):6817-6828
Molecular Biology Reports - A member of the Trk family of neurotrophin receptors, tropomyosin receptor kinase B (TrkB, encoded by the NTRK2 gene) is an increasingly important target in various... 相似文献
307.
Nils Chr. Stenseth Jo?l M. Durant Mike S. Fowler Erik Matthysen Frank Adriaensen Niclas Jonzén Kung-Sik Chan Hai Liu Jenny De Laet Ben C. Sheldon Marcel E. Visser André A. Dhondt 《Proceedings. Biological sciences / The Royal Society》2015,282(1807)
Climate change is expected to have profound ecological effects, yet shifts in competitive abilities among species are rarely studied in this context. Blue tits (Cyanistes caeruleus) and great tits (Parus major) compete for food and roosting sites, yet coexist across much of their range. Climate change might thus change the competitive relationships and coexistence between these two species. Analysing four of the highest-quality, long-term datasets available on these species across Europe, we extend the textbook example of coexistence between competing species to include the dynamic effects of long-term climate variation. Using threshold time-series statistical modelling, we demonstrate that long-term climate variation affects species demography through different influences on density-dependent and density-independent processes. The competitive interaction between blue tits and great tits has shifted in one of the studied sites, creating conditions that alter the relative equilibrium densities between the two species, potentially disrupting long-term coexistence. Our analyses show that long-term climate change can, but does not always, generate local differences in the equilibrium conditions of spatially structured species assemblages. We demonstrate how long-term data can be used to better understand whether (and how), for instance, climate change might change the relationships between coexisting species. However, the studied populations are rather robust against competitive exclusion. 相似文献
308.
Reduced dopamine and glutamate neurotransmission in the nucleus accumbens of quinpirole‐sensitized rats hints at inhibitory D2 autoreceptor function 下载免费PDF全文
309.
Xanthomonas campestris attenuates virulence by sensing light through a bacteriophytochrome photoreceptor 下载免费PDF全文
310.
Gerda Strifler Eszter Tuboly Edit Szél Enik? Kaszonyi Chun Cao József Kaszaki András Mészáros Mihály Boros Petra Hartmann 《PloS one》2016,11(1)