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排序方式: 共有697条查询结果,搜索用时 15 毫秒
21.
Yordanka Gluhcheva Irena Pashkunova-Martic Martin Schaier Ivelin Vladov Silviya Stoykova Emilia Petrova Ekaterina Pavlova Peter Dorkov Thomas H. Helbich Bernhard Keppler Juliana Ivanova 《International journal of molecular sciences》2022,23(8)
Lead (Pb) exposure induces severe nephrotoxic effects in humans and animals. Herein, we compare the effects of two chelating agents, salinomycin and deferiprone, on Pb-induced renal alterations in mice and in the homeostasis of essential elements. Adult male mice (Institute of Cancer Research (ICR)) were randomized into four groups: control (Ctrl)—untreated mice administered distilled water for 28 days; Pb-exposed group (Pb)—mice administered orally an average daily dose of 80 mg/kg body weight (BW) lead (II) nitrate (Pb(NO3)2) during the first two weeks of the experimental protocol followed by the administration of distilled water for another two weeks; salinomycin-treated (Pb + Sal) group—Pb-exposed mice, administered an average daily dose of 16 mg/kg BW salinomycin for two weeks; deferiprone-treated (Pb + Def) group—Pb-exposed mice, administered an average daily dose of 20 mg/kg BW deferiprone for 14 days. The exposure of mice to Pb induced significant accumulation of the toxic metal in the kidneys and elicited inflammation with leukocyte infiltrations near the glomerulus. Biochemical analysis of the sera revealed that Pb significantly altered the renal function markers. Pb-induced renal toxicity was accompanied by a significant decrease in the endogenous renal concentrations of phosphorous (P), calcium (Ca), copper (Cu) and selenium (Se). In contrast to deferiprone, salinomycin significantly improved renal morphology in Pb-treated mice and decreased the Pb content by 13.62% compared to the Pb-exposed group. There was also a mild decrease in the renal endogenous concentration of magnesium (Mg) and elevation of the renal concentration of iron (Fe) in the salinomycin-treated group compared to controls. Overall, the results demonstrated that salinomycin is a more effective chelating agent for the treatment of Pb-induced alterations in renal morphology compared to deferiprone. 相似文献
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23.
Carbon foam derived from pitches modified with mineral acids by a low pressure foaming process 总被引:1,自引:0,他引:1
Carbon foams with an anisotropic texture and high mechanical strength were produced using precursors obtained after thermo-oxidation treatment of commercial coal-tar pitch with H2SO4 and HNO3. The investigations of the relation between the properties of the precursor and the structure of obtained foam indicate, that the composition and softening point of the pitch precursor significantly affect the foaming process, foam structure and foam mechanical strength. The composition and properties of the modified pitches allow foam formation at relatively low pressure and fast heating rate during the foaming process without a stabilization treatment. The foaming process of pitch-based carbon foams, pre-treatment of the precursors, and the properties of resultant foams are discussed in this paper. 相似文献
24.
A. N. Petrova H. Radziszewska L. Kaczmarek M. Klih I. G. Brodova M. Steglinski 《The Physics of Metals and Metallography》2016,117(12):1237-1244
Methods of electron microscopy and X-ray diffraction have been used to investigate structural and phase transformations in the aluminum alloy of grade A2024 (Al–4.5 Cu–1.37 Mg–0.61 Mn–0.07 Si–0.27 Fe–0.02 Zn–0.02 Ti (wt %)) after aging and deformation by shear under high quasi-static pressure. It has been shown that the combination of two-stage aging with megaplastic deformation leads to the refinement of the structure to a nanolevel and to strengthening of the alloy (to an increase in the microhardness to 3000 MPa). The values of true deformation at which the deformation-induced dissolution of the particles of the strengthening S phase occurs have been determined. 相似文献
25.
A novel, low-temperature process is proposed for the synthesis of the multiferroic compound BiFeO3. It enables the preparation of nanoparticulate material at temperatures as low as 200–250°C. An important role in the low-temperature synthesis of bismuth orthoferrite is played by ammonium nitrate additions and excess bismuth oxide. 相似文献
26.
A. V. Bushuev V. N. Zubarev A. F. Kozhin A. G. Nikolaev E. V. Petrova A. A. Portnov I. M. Proshin 《Atomic Energy》2002,92(5):403-407
New semiconductor -ray detectors based on CdZnTe have been developed in the last few years, and they are now being widely used. Their advantages are small size and possibility of operating without cooling. In the present work, these detectors are used to measure the radiation from spent fuel assemblies in holding ponds and dry storage sites, unirradiated nuclear materials, and radioactive wastes. The results are analyzed and compared with other types of detectors. The possible applications of CdZnTe-type detectors are determined. 相似文献
27.
Conclusions
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 38–43, April, 2000. 相似文献
1. | The studied method for modelling the hardening of nitrided layers as a function of their structure makes it possible to predict successfully the hardness of steels after surface impregnation. |
2. | The performed calculations and experiments have shown that the alloying elements (Cr, V, Mo, W, Ti) increase substantially the efficiency of the solid-solution hardening by nitrogen due to the enhanced dissolution of nitrogen in iron. |
3. | The calculations of dispersion hardening of binary Fe-AE alloys by nitrides have shown that the hardness can be increased to a maximum level due to the formation of coherent nitride particles of the alloying elements, Ti, Cr, and V in the first place. This is confirmed by experimental results. |
4. | The described method can be used for optimizing the chemical composition of steels subjected to nitriding from the standpoint of the amount and type of the nitride-forming element with the aim to provide the requisite hardness level. |
5. | By controlling the nitriding parameters and using subsequent aging at a specified temperature we can obtain various structures in the zone of internal nitriding and optimize the mechanical properties (hardness in particular) of steels after surface impregnation. |
28.
1. | By calculating the level of dispersion hardening of alloys due to coherent nitrides in nitriding we can choose the most effective hardening nitride by two criteria, i.e., the minimum volume fraction of segregations and the minimum concentration of the alloying element. |
2. | From the standpoint of the maximum volume fraction of segregations in nitriding the most effective hardeners for Fe-, Co-, and Ni-matrices are hafnium and zirconium nitrides. With allowance for the requirement that the concentration of the alloying element be minimum, the maximum hardening effect is provided by titanium nitrides. |
29.
Translated from Fiziko-Khimicheskaya Mekhanika Materialov, No. 1, pp. 80–83, January–February, 1989. 相似文献
30.