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101.
The Effectiveness of Fish Oil Supplementation in Asthmatic Rats is Limited by an Inefficient Action on ASM Function 总被引:1,自引:1,他引:0
D. T. S. Z. Miranda A. L. Zanatta B. C. L. Dias R. T. H. Fogaça J. B. B. Maurer L. Donatti P. C. Calder A. Nishiyama 《Lipids》2013,48(9):889-897
Episodes of acute exacerbation are the major clinical feature of asthma and therefore represent an important focus for developing novel therapies for this disease. There are many reports that the n-3 fatty acids found in fish oil exert anti-inflammatory effects, but there are few studies of the action of fish oil on airway smooth muscle (ASM) function. In the present investigation, we evaluated the effect of fish oil supplementation on smooth muscle force of contraction in ovalbumin-induced asthmatic Wistar rats, and its consequences on static lung compliance, mucus production, leukocyte chemotaxis and production of proinflammatory cytokines. Fish oil supplementation suppressed the infiltration of inflammatory cells into the lung in asthmatic animals (2.04 ± 0.19 × 106 cells vs. 3.33 ± 0.43 × 106 cells in the control asthmatic group; P < 0.05). Static lung compliance increased with fish oil supplementation in asthmatic rats (0.640 ± 0.053 mL/cm H2O vs. 0.399 ± 0.043 mL/cm H2O; P < 0.05). However, fish oil did not prevent asthma-associated lung eosinophilia and did not affect the concentrations of tumor necrosis factor-α and interleukin-1β in lung tissue or the proportion of the airways obliterated with mucus. Fish oil had no effect on the force of contraction in asthmatic rats in response to acetylcholine (3.026 ± 0.274 mN vs. 2.813 ± 0.364 mN in the control asthmatic group). In conclusion, although fish oil exerts some benefits in this model of asthma, its effectiveness appears to be limited by an inefficient action on airway smooth muscle function. 相似文献
102.
Fr��d��ric Chardard Fr��d��ric Dias Hai Yen Nguyen Jean-Marc Vanden-Broeck 《Journal of Engineering Mathematics》2011,70(1-3):175-189
Free-surface flows past submerged obstacles in a channel are considered. The fluid is assumed to be inviscid and incompressible and the flow to be irrotational. The first-order approximation of long nonlinear surface waves over one or two bumps results in a forced Korteweg?Cde Vries (fKdV) equation. Solutions of the stationary fKdV equation are constructed and their stability is studied, either analytically or numerically. These various solutions include solitary waves over a single bump, solitary waves with two humps over a double bump, table-top solutions over a double bump and fronts. 相似文献
103.
M. Dias P. A. Carvalho U. V. Mardolcar O. Tougait H. Noël A. P. Gonçalves 《Metallurgical and Materials Transactions A》2013,44(5):2270-2284
The liquidus projection of the Fe-rich corner of the B-Fe-U phase diagram is proposed based on powder X-ray diffraction measurements, differential thermal analysis, and scanning electron microscopy observations complemented by energy dispersive X-ray spectroscopy. The present work demonstrates the existence of 10 ternary reactions together with 18 monovariant lines and establishes their location and approximate temperatures. The ternary compounds existing in this region of the B-Fe-U ternary phase diagram, UFe3B2, UFe4B, and U2Fe21B6, were confirmed to form by ternary peritectic reactions, yet UFe4B and U2Fe21B6 have minute primary crystallization fields, indicating a more challenging preparation of single crystals for these compounds when compared with UFe3B2. 相似文献
104.
Jerry Ray Dias 《Polycyclic Aromatic Compounds》2013,33(1-4):83-91
Two 2-dimensional tableaus of heterocyclic molecular systems are shown to have molecular graphs that are pairwise strongly subspectral (having a preponderance of common eigenvalues). Based on this result, the electronic similarity of candidate chromophores are proposed. 相似文献
105.
J.P. Nobre A.C. Batista L. Coelho A.M. Dias 《Journal of Materials Processing Technology》2010,210(15):2285-2291
Two experimental methods to characterize the mechanical behavior of work-hardened surface layers of metallic materials, induced by mechanical surface treatments, are described and discussed. The study was conducted using two steels with different mechanical properties, subjected to a similar shot-peening treatment. To characterize the elastic–plastic behavior of the surface layers affected by shot-peening, the X-ray diffraction assisted four-point bending method (XRDABM) and the normalized hardness variation method (NHVM) were applied. The results were compared and discussed taking into account the advantages and disadvantages of both methods. Similar yield strength values of the treated surfaces were found by both proposed methods. Taking into account their measuring characteristics, these can be considered complementary methods. 相似文献
106.
Borrel V. Legendre F. Dias de Amorim M. Fdida S. 《Networking, IEEE/ACM Transactions on》2009,17(3):831-842
Assessing mobility in a thorough fashion is a crucial step toward more efficient mobile network design. Recent research on mobility has focused on two main points: analyzing models and studying their impact on data transport. These works investigate the consequences of mobility. In this paper, instead, we focus on the causes of mobility. Starting from established research in sociology, we propose SIMPS, a mobility model of human crowds with pedestrian motion. This model defines a process called sociostation, rendered by two complimentary behaviors, namely socialize and isolate, that regulate an individual with regard to her/his own sociability level. SIMPS leads to results that agree with scaling laws observed both in small-scale and large-scale human motion. Although our model defines only two simple individual behaviors, we observe many emerging collective behaviors (group formation/splitting, path formation, and evolution). 相似文献
107.
108.
Mrcia A. F. S. Neves Fernanda M. B. Coutinho Marcos L. Dias Renata A. Simo Carlos A. Achete 《应用聚合物科学杂志》2002,84(3):541-551
Macroporous poly(styrene‐co‐divinylbenzene) and poly(divinylbenzene) beads were synthesized by modified suspension polymerization in the presence of different mixtures of toluene and heptane as porogen agent. Through atomic force microscopy, it was possible to identify the microspheres and the channels between them that constitute the bead pores. It was also possible to make a comparison with the results obtained by nitrogen desorption, a traditional technique used to determine the porosity of macroporous copolymers in the dry state. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 541–551, 2002; DOI 10.1002/app.10290 相似文献
109.
110.