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51.
Timothy Joseph-Horne Angelina Carelli Derek Hollomon Steven L. Kelly 《Pest management science》1995,44(1):33-38
Resistance to azole fungicides in Ustilago maydis (DC) Corda has been examined using the mutant erg 40, a newly isolated mutant TriR-1 and erg 40 revertants. Azole-induced growth arrest of the wild type did not support an obvious role for 3,6-diol in the mode of action has is clear for Saccharomyces cerevisiae Meyer ex Hansen. The level of microsomal P450 of erg 40 was identical to that of the parent, and reversion analysis showed no evidence of mutation in the sterol Δ5(6) desaturase, as would be expected for a S. cerevisiae mutant accumulating 14α-methylfecosterol. Resistance appeared to be due to a single mutation in P450 14αdm. It is proposed that the orthologous forms of fungal sterol Δ5(6) desaturases have varied responses when attempting to utilise 14α-methylated substrates. 相似文献
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Gutiérrez-Barroso A Anaya-López JL Lara-Zárate L Loeza-Lara PD López-Meza JE Ochoa-Zarzosa A 《Veterinary immunology and immunopathology》2008,121(1-2):113-122
The incidence of mastitis in dairy cattle is highest at the drying off period and parturition, which are characterized by high levels of the lactogenic hormone prolactin (PRL). One of the most frequently isolated contagious pathogens causing mastitis is Staphylococcus aureus. However, the role of PRL on S. aureus infection in mammary epithelium has not been studied. In this work we evaluated the effect of bovine PRL (bPRL) on S. aureus internalization in a primary culture of bovine mammary epithelial cells (bMEC) and on the expression of cytokine and innate immune response genes. Our data show that 5ng/mL bPRL enhances approximately 3-fold the internalization of S. aureus (ATCC 27543) into bMEC. By RT-PCR analysis, we showed that bPRL is able to up-regulate the expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and inducible nitric oxide synthase (iNOS) mRNAs. However, bPRL together with S. aureus did not modify the expression of TNF-alpha and iNOS mRNAs, while it down-regulated the expression of beta-defensin and IL-1beta mRNAs, as well as nitric oxide production, suggesting that infection and bPRL together can inhibit elements of the host immune response. To our knowledge, this is the first report that shows a role of bPRL during the internalization of S. aureus into bMEC. 相似文献
54.
The cat has been used extensively as an animal model for urogenital studies involving the pudendal nerve. However, discrepancies persist in the literature regarding the origin of the dorsal nerve of the penis (DNP). This study used gross dissections and serial histological cross sections to demonstrate that the DNP arises from the deep perineal nerve and not the sensory afferent branch as previously reported. This finding indicates a better than previously appreciated neuroanatomical homology between the cat and human. 相似文献
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Noelia Gonzlez-Ballesteros Lara Diego-Gonzlez Mariano Lastra-Valdor Maria Grimaldi Antonella Cavazza Franca Bigi M. Carmen Rodríguez-Argüelles Rosana Simn-Vzquez 《Marine drugs》2022,20(3)
This study reports on the green and cost-efficient synthesis of gold nanoparticles from three different red algae extracts. The nanoparticles synthesized were fully characterized by UV-Vis spectroscopy, HRTEM, and Z-potential. Relevant components occurring in the extracts, such as polysaccharides or phenolic content, were assessed by analytical techniques such as spectrophotometric assays and liquid chromatography. Finally, the antioxidant, antitumoral, and anti-inflammatory potential of both the extracts and the gold nanoparticles synthesized were analyzed in order to determine a possible synergistic effect on the nanoparticles. The results obtained confirmed the obtainment of gold nanoparticles with significant potential as immunotherapeutic agents. The therapeutic potential of these nanoparticles could be higher than that of inert gold nanoparticles loaded with bioactive molecules since the former would allow for higher accumulation into the targeted tissue. 相似文献
57.
Projecting future fish supplies using stock dynamics and demand 总被引:1,自引:0,他引:1
Roehlano M. Briones 《Fish and Fisheries》2006,7(4):303-315
Supply–demand models, which are commonly used in food policy analysis, have been recently applied to generate projections of future fish supplies. However, these models routinely ignore stock dynamics; hence, threats to sustainability due to declining fish stocks are addressed, at best, by exogenous changes in resource productivity. Such a device is ad hoc, as it is unclear whether the assumed shifts are consistent with known patterns of population adjustment. On the other hand, bioeconomic models incorporate stock dynamics, but typically omit price adjustment arising from the interaction of demand and supply. An applied supply–demand model with stock dynamics combines the strengths of both approaches. However, data problems constrain the formulation of such a model. Instead, this study presents a prototype bioeconomic supply–demand model. Simulations show trends in fish supply that fail to appear in either supply–demand or bioeconomic models. Secular demand growth causes initial production growth, followed by stagnation, and then persistent decline. Moreover, under constant pressure from rising demand, capture production fails to recover completely from adverse population shock (such as may be induced by climate change). The prototype model highlights the potential usefulness of an applied bioeconomic supply–demand model for food policy and fisheries management, and provides a template for future work. 相似文献
58.
J F Fernandez-Garayzabal M Blanco J A Vazquez-Boland V Briones J A Garcia C Delgado M Domingo J Marco L Dominguez 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(7):513-518
Twenty-two silage samples were analyzed for the presence of L. monocytogenes using five Listeria selective plating media, with and without previous selective enrichment step. L. monocytogenes was recovered from 3 samples by both procedures, but direct plating allowed the quantification of Listeria population. Two of these positive samples were implicated in outbreaks of listeriosis in sheep; the L. monocytogenes population in these samples was about 10(6) cells/g. The L. monocytogenes population in the other positive sample was 10(3) cells/g. Direct isolation of L. monocytogenes was only possible from LPM, PALCAM and LSAMm media. MOX and LSM media were not selective enough to allow direct Listeria isolation. In our hands, LSAMm was the most suitable plating medium for the direct isolation and specific quantification of L. monocytogenes from silage employing a red blood cells overlay technique. 相似文献
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Powerful relativistic jets are among the most ubiquitous and energetic observational consequences of accretion around supermassive black holes in active galactic nuclei and neutron stars and stellar-mass black holes in x-ray binary (XRB) systems. But despite more than three decades of study, the structure and composition of these jets remain unknown. Here we present spatially resolved x-ray spectroscopy of arc second-scale x-ray jets from XRB SS 433 analyzed with the Chandra advanced charge-coupled device imaging spectrometer. These observations reveal evidence for a hot continuum and Doppler-shifted iron emission lines from spatially resolved regions. Apparently, in situ reheating of the baryonic component of the jets takes place in a flow that moves with relativistic bulk velocity even more than 100 days after launch from the binary core. 相似文献