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61.
Aline T. PERES Maria A. DALBONI Maria E. CANZIANI Silvia R. MANFREDI Jose Tarcisio G. CARVALHO Marcelo C. BATISTA Lilian CUPPARI Aluisio B. CARVALHO Rosa M. A. MOYSES Nadia GUIMARÃES Vanda JORGETTI Maria C. ANDREOLI Sergio A. DRAIBE Miguel CENDOROGLO 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(3):271-277
It has been suggested that phosphate binders may reduce the inflammatory state of hemodialysis (HD) patients. However, it is not clear whether it has any effect on oxidative stress. The objective of this study was to evaluate the effect of sevelamer hydrochloride (SH) and calcium acetate (CA) on oxidative stress and inflammation markers in HD patients. Hemodialysis patients were randomly assigned to therapy with SH (n=17) or CA (n=14) for 1 year. Before the initiation of therapy (baseline) and at 12 months, we measured in vitro reactive oxygen species (ROS) production by stimulated and unstimulated polymorphonuclear neutrophils and serum levels of tumor necrosis factor α, interleukin-10, C-reactive protein, and albumin. There was a significant reduction of spontaneous ROS production in both groups after 12 months of therapy. There was a significant decrease of Staphylococcus aureus stimulated ROS production in the SH group. There was a significant increase in albumin serum levels only in the SH group. In the SH group, there was also a decrease in the serum levels of tumor necrosis factor α and C-reactive protein. Our results suggest that compared with CA treatment, SH may lead to a reduction in oxidative stress and inflammation. Therefore, it is possible that phosphate binders exert pleiotropic effects on oxidative stress and inflammation, which could contribute toward decreasing endothelial injury in patients in HD. 相似文献
62.
制备并表征了化合物3,6-二(3'-氨基呋咱-4-基)-1,4-二氧杂-2,5-二氮杂环己-2,5-二烯(BADDD) .其晶体结构参数为:Mr=252.17,三斜晶系,P-1空间群,a=0.48616 (10) nm,b=0.5237 (2) nm,c=0.97076 (19) nm,α=102.25(3)°,β=93.631(17)°,γ=101.88 (2)°,V=0.23489 (12) nm3,Z=1,Dc=1.783g·cm-3,λ (MoKα)=0.071073 nm,μ(MoKα)=0.153 mm-1,F(000)=128,T=294 (2) k,R1=0.0351 and wR2=0.0875.BADDD分子由两个氨基呋咱环和一个由两个O原子,两个N原子和两个C原子组成的六元杂环构成.分子具有中心对称性. 相似文献
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66.
《Advanced Robotics》2013,27(7):703-717
Control of legged robots with fast gaits is addressed in this paper. These kind of systems interact intermittently with the environment. We propose a viable approach for the control of hopping gaits for legged robots. This control approach is based on controlled limit cycles (CLC) for stabilization of fast gaits (closed orbits) for legged robots. The designed control system generates the desired trajectories (on-line) and control inputs. Robustness of the proposed control with respect to parameter variation and disturbance is illustrated by numerical simulations. Viable definitions of gaits and their admissibility are introduced. 相似文献
67.
E. M. Popenko A. A. Gromov Yu. Yu. Shamina A. P. Il’in A. V. Sergienko N. I. Popok 《Combustion, Explosion, and Shock Waves》2007,43(1):46-50
The effect of small additives (1.25–5.00%) of ultrafine aluminum powders (UFAP) on the rheology and combustion of model four-component
energetic condensed systems is studied. It is found that the addition of UFAP decreases the temperature of HMX decomposition.
Small additives of UFAP increase the burning rate of model energetic condensed systems and decrease the exponent ν in the burning rate law without deteriorating the rheological characteristics of the model propellants.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 1, pp. 54–59, January–February, 2007. 相似文献
68.
Li Yang Haiyang Zhang Tianwei Tan Ata Ur Rahman 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(4):611-617
BACKGROUND: Adsorption of puerarin on native resin polystyrene (PS) and oligo‐β‐cyclodextrin‐coupled matrix (PS‐CDP) was studied for interactions between the adsorbents and the adsorbates. The sorption mechanism on PS‐CDP was investigated using the isosteric heat approach and nuclear magnetic resonance (NMR) spectroscopy. RESULTS: The equilibrium adsorption data of puerarin on the two matrices PS and PS‐CDP (polystyrene‐based matrix before and after coupling by oligo‐β‐cyclodextrin) in the temperature range 288–318 K were well fitted to the Freundlich adsorption isotherm model. The energetic heterogeneity of the media was observed based on the result that the values of isosteric enthalpy were quantitatively correlated with the fractional loading of puerarin adsorption. The more heterogeneous surface of PS‐CDP compared with PS was attributed to the complexation between puerarin and β‐cyclodextrin (β‐CD). NMR studies validated the formation of an inclusion complex puerarin/β‐CD. CONCLUSION: Thermodynamic and NMR studies confirmed that multi‐interaction cooperatively governed the isolation of puerarin from aqueous solution on PS‐CDP matrix. Copyright © 2009 Society of Chemical Industry 相似文献
69.
Zinc-rich ethyl silicate coatings are quite successful in protecting steel against corrosion under severe exposing conditions. In spite of providing excellent cathodic protection to steel structure after film curing, two-component zinc-rich ethyl silicate coatings have some limitations, one of which is inadequate shelf life as a result of in-can binder gelation. 相似文献
70.
Shock initiation is one of the most important properties of energetic materials, which must transition to detonation exactly
as intended when intentionally shocked and not detonate when accidentally shocked. The development of Manganin pressure gauges
that are placed inside the explosive charge and record the buildup of pressure upon shock impact has greatly increased the
knowledge of these reactive flows. This experimental data, together with similar data from electromagnetic particle velocity
gauges, has allowed us to formulate the Ignition and Growth model of shock initiation and detonation in hydrodynamic computer
codes for predictions of shock initiation scenarios that cannot be tested experimentally. An important problem in shock initiation
of solid explosives is the change in sensitivity that occurs upon heating (or cooling). Experimental Manganin pressure gauge
records and the corresponding Ignition and Growth model calculations are presented for two solid explosives, LX-17 [92.5%
triaminotrinitrobenzene (TATB) with 7.5% Kel-F binder] and LX-04 [85% octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX)
with 15% Viton binder] at several initial temperatures.
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Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 6, pp. 181–192, November–December, 2005. 相似文献