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Cytokine profile in Egyptian hepatitis C virus genotype-4 in relation to liver disease progression 被引量:4
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作者 Abdel-Rahman N Zekri Mohammed S El-Din Ashour +3 位作者 ahmed hassan Hanaa M Alam El-Din Amal MR El-Shehaby Maha A Abu-Shady 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第42期6624-6630,共7页
AIM: To observe the imbalance between T helper cell Th1 and Th2 cytokines in several chronic hepatitis disease at different stages of disease progression.METHODS: We measured the cytokine levels of Th1 (IL-2 and IL-2R... AIM: To observe the imbalance between T helper cell Th1 and Th2 cytokines in several chronic hepatitis disease at different stages of disease progression.METHODS: We measured the cytokine levels of Th1 (IL-2 and IL-2R), Th2 (IL-10) and the pro-inflammatory cytokines (IL-6 and IL-6R and TNF and TNF-RⅠ and Ⅱ)by the ELISA technique in the sera of 33 hepatocellular carcinoma (HCC) patients and 20 chronic liver disease (CLD) patients. In addition, 20 asymptomatic hepatitis C virus carriers and 20 healthy subjects negative for hepatitis C virus(HCV) markers served as controls.RESULTS: Anti-HCV antibodies were found to be positive in 94% of HCC cases and 75% of CLD cases.On the other hand, HCV viremia was detected using RTPCR in 67% of HCC cases and 65% of CLD cases. HBsAg was positive in 9% of HCC cases and 30% of CLD cases.Also bilharzial-Ab was positive in 55% of HCC cases,65% of CLD cases and in 70% of asymptomatic carriers (ASC). HCC patients had significantly higher values of IL-2R, TNF-RⅡ (P<0.001), and TNF-RⅠ (P>0.05), but lower TNFα (P<0.001) and IL-6 (P = 0.032) in comparison to ASC. But, in comparison to non-cancer controls, HCC patients had higher values of IL-2R, IL-6R, TNF-RⅠ and TNF-RⅡ, but lower TNF-α (P<0.001). CLD patients had higher IL-2R, TNF-RⅠ, and TNF-RⅡ (P<0.001) than ASC. But, in comparison to non-cancer controls, CLD patients had higher values of IL-2R, TNF-RⅠ and TNF-RⅡ, but lower TNF-α (P<0.001). IL-10 was higher (though not significantly) in HCC and CLD patients than in symptomatic carriers and non-cancer controls.CONCLUSION: Liver disease progression from CLD to HCC due to HCV genotype-4 infection is associated with an imbalance between Th1 and Th2 cytokines. IL-2R,TNF-RⅠ, and TNF-RⅡ could be used as potential markers. 展开更多
关键词 细胞因子 埃及 丙型肝炎病毒 肝疾病
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Variant Computer Aided Process Planning System for Rotational Parts 被引量:1
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作者 ahmed hassan 姚振强 蔡建国 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期74-76,共3页
The amount of material must be removed away to produce the final product should minimize, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases mach... The amount of material must be removed away to produce the final product should minimize, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times. Noticing in recent years that the world is running out of mineral resources, and the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. This paper proposed a variant CAPP system for rotational parts based on the concept of group technology, this system accepts part features characteristics code number as an input and provides operation details for manufacturing route with the suitable primary processes required to produce the blank work piece as an output. 展开更多
关键词 转动部件 计算机辅助工艺计划系统 加工件 CAPP
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Relative performance of novel blast wave mitigation system to conventional system based on mitigation percent criteria
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作者 Moustafa Esa Mostafa S.Amin ahmed hassan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期912-922,共11页
Recent researches focused on developing robust blast load mitigation systems due to the threats of terrorist attacks.One of the main embraced strategies is the structural systems that use mitigation techniques.They ar... Recent researches focused on developing robust blast load mitigation systems due to the threats of terrorist attacks.One of the main embraced strategies is the structural systems that use mitigation techniques.They are developed from a combination of structural elements and described herein as conventional systems.Among the promising techniques is that redirect the waves propagation through hollow tubes.The blast wave propagation through tubes provides an efficient system since it combines many blast wave phenomena,such as reflection,diffraction,and interaction.In this research,a novel blast load mitigation system,employed as a protection fence,is developed using a technique similar to the technique of the bent tube in manipulating the shock-wave.The relative performance of the novel system to the conventional system is evaluated based on mitigation percent criteria.Performances of both systems are calculated through numerical simulation.The proposed novel system proved to satisfy high performance in mitigating the generated blast waves from charges weight up to 500 kg TNT at relatively small standoff distances(5 m and 8 m).It mitigates at least 94%of the blast waves,which means that only 6%of that blast impulse is considered as the applied load on the targeted structure. 展开更多
关键词 Blast mitigation Blast barriers Protection system Mitigation percent Protection evaluation
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A Prototype of CAPP System for Rotational Parts
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作者 ahmed hassan 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期13-,共1页
Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the c... Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. The amount of material must be removed away to produce the final product should be minimized, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times. This paper proposed a variant CAPP system for rotational parts based on the concept of group technology, this system accepts part features characteristics code number as an input and specify operation details for manufacturing route with the suitable primary processes required to produce the blank work piece as an output. 展开更多
关键词 CAPP blank work piece primary processes
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Optimization of Cutting Parameters for Face Milling Titanium Alloy Using MQL
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作者 ahmed hassan 姚振强 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期9-12,共4页
When using MQL as a cooling technique, many parameters have to be adjusted. The Taguchi method was used in this study to investigate the cutting characteristics of face milling of titanium alloys using PVD-coated inse... When using MQL as a cooling technique, many parameters have to be adjusted. The Taguchi method was used in this study to investigate the cutting characteristics of face milling of titanium alloys using PVD-coated inserts. To find the optimal volume removed and surface roughness, an orthogonal array, the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) were employed. The optimum cutting parameters was obtained. Throughout this study, it was found that the feed rate is the most influencing cutting parameter in the face milling of titanium alloys. 展开更多
关键词 端面铣削 钛合金 达柯铸铁 切削参数
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Dry face milling of titanium alloys
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作者 ahmed hassan 《Journal of University of Science and Technology Beijing》 CSCD 2004年第6期545-548,共4页
In machining titanium alloys, cutting tools generally wear out very rapidly because of the high cutting temperature resulted from the low thermal conductivity and density of the work material. In order to increase the... In machining titanium alloys, cutting tools generally wear out very rapidly because of the high cutting temperature resulted from the low thermal conductivity and density of the work material. In order to increase the tool life, it is necessary to suppress the cutting heat as much as possible by applying an abundant amount of coolant, but this will entail serious techno-environmental and biological problems. To study the performance and avoid these limitations, a PVD-coated insert was used to the dry face mill of (α +β) titanium alloys. As a result it was found that the inserts exhibit an excellent cutting performance at low cutting speeds and feed rates, and there is no significant difference in the dominant insert failure mode between the wet and dry cutting in discontinuous cutting. 展开更多
关键词 硬质合金刀具 端面铣削 钛合金 不连续切削
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Two-color multiphoton in vivo imaging with a femtosecond diamond Raman laser 被引量:1
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作者 Evan P Perillo Jeremy W Jarrett +7 位作者 Yen-Liang Liu ahmed hassan Daniel C Fernée John R Goldak Andrei Bonteanu David J Spence Hsin-Chih Yeh Andrew K Dunn 《Light(Science & Applications)》 SCIE EI CAS CSCD 2017年第1期400-407,共8页
Two-color multiphoton microscopy through wavelength mixing of synchronized lasers has been shown to increase the spectral window of excitable fluorophores without the need for wavelength tuning.However,most currently ... Two-color multiphoton microscopy through wavelength mixing of synchronized lasers has been shown to increase the spectral window of excitable fluorophores without the need for wavelength tuning.However,most currently available dual output laser sources rely on the costly and complicated optical parametric generation approach.In this report,we detail a relatively simple and low cost diamond Raman laser pumped by a ytterbium fiber amplifier emitting at 1055 nm,which generates a first Stokes emission centered at 1240 nm with a pulse width of 100 fs.The two excitation wavelengths of 1055 and 1240 nm,along with the effective two-color excitation wavelength of 1140 nm,provide an almost complete coverage of fluorophores excitable within the range of 1000–1300 nm.When compared with 1055 nm excitation,two-color excitation at 1140 nm offers a 90%increase in signal for many far-red emitting fluorescent proteins(for example,tdKatushka2).We demonstrate multicolor imaging of tdKatushka2 and Hoechst 33342 via simultaneous two-color two-photon,and two-color three-photon microscopy in engineered 3D multicellular spheroids.We further discuss potential benefits and applications for two-color three-photon excitation.In addition,we show that this laser system is capable of in vivo imaging in mouse cortex to nearly 1 mm in depth with two-color excitation. 展开更多
关键词 MICROSCOPY nonlinear processes three-dimensional imaging ultrafast lasers
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