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111.
GI Kutsenko EA Tishuk SS Misiulin VM Aseev EI Gorbatov IuV Ozerov 《Canadian Metallurgical Quarterly》1996,(6):6-10
A socioeconomic and medicodemographic analysis of modern problems related to population health protection in the oil and gas extraction regions of Tyumen Province has been carried out under conditions of radical reconstruction of the national economy. Changes in the parameters of natural migration of the population for each year over a period of 1991 to 1995 are followed up, and specific features of the migration processes, effects of socioeconomic and medical factors on the health status of individual population groups, rates of increment in the number of disabled subjects, and population mortality from various causes analyzed. The authors discuss the status of public health services and offer measures for improving their efficacy in the above regions. 相似文献
112.
GA Koroleva VA Lashkevich EV Denisova NV Tereshkina IP Khoroshilova-Maslova LA Katargina AN Lukashev GI Krichevskaia AV Khvatova 《Canadian Metallurgical Quarterly》1998,43(5):204-216
Follow-up (5.5 years) of monkeys with a history of acute enterovirus uveitis (AEU) after intraocular infection with ophthalmotropic ECHO 11 and ECHO 19 strains showed progressive changes in the infected eye; destruction of the iris, formation of films in the anterior chamber of the eye, deformation of the pupil, and signs of cataract and glaucoma. A short (1-30 days) stage of active reproduction of infective virus (up to 10(10) TCD50/g tissue in the first days postinfection) was followed by the second very long stage of limited specific multiplication of virus in ocular tissues. The virus was not detected during the second stage, but its components (virusspecific antigen and crystalloid accumulations of virions) were found in ophthalmic and conjunctival tissues; moreover, high levels of neutralizing antibodies were detected in the blood. The results indicate AEU transformed into a stubborn persistent infection of the eye in monkeys. The findings of this follow-up and published reports about many-year follow-up of children with AEU permit us to classify a post-uveitis disease as a special nosological form of a persistent enterovirus infection and denote it as enterovirus post-uveitis syndrome. The main signs of this syndrome are a history of AEU, progressive destructive changes in the anterior segment of the eye, presence of virus components in ocular tissues in remote periods after infection, and high antibody level in the blood. 相似文献
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在无线传感器网络( WSNs)的应用中,网络中的节点需要将采集到的数据信息传送到汇聚节点,其信息传输的可靠性是十分重要的。然而,由于无线通信信道容易受到干扰和噪音的影响,极限情况时甚至可能造成数据传输失败,这对无线传感器网络的正常工作提出了极大挑战。针对上述问题,提出一种可靠拓扑的生成算法,通过该算法设计了一组可靠的路由拓扑,并通过仿真验证了其可靠性。 相似文献
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GI Klebanov AB Kapitanov Teselkin YuO IV Babenkova BA Zhambalova OB Lyubitsky OA Nesterova OV Vasil'eva IN Popov G Lewin Vladimirov YuA 《Canadian Metallurgical Quarterly》1998,12(2):287-300
The antioxidant properties of the carotenoid lycopene were compared in three different model oxidative systems. In egg yolk liposomes, in the presence of 2.5 mM FeSO4 and 200 mM ascorbate, lycopene, alpha-tocopherol, and beta-carotene inhibited the accumulation of lipid peroxidation products reacting with 2-thiobarbituric acid (TBARS) in a dose-dependent mode, with the concentration of half-inhibition being 80, 30 and 130 mM, respectively. In the liposomes subjected to illumination with a He-Ne laser (632.8 nm) at a dose of 10.5 J/cm2, in the presence of 32.5 micrograms/ml hematoporphyrin derivatives (Fotogem, NIOPIC, Russia) TBARS accumulated, and this effect was inhibited by lycopene, alpha-tocopherol, and dihydroquercetin with approximately equal efficiencies (the half-inhibition concentrations were 10(-5) mM). In both systems studied, sodium azide at a concentration of 10 mM inhibited the TBARS accumulation by no more than 20%. Apparently, the inhibitory action of not only alpha-tocopherol, but also beta-carotene and lycopene was the result of their antiradical action, rather than quenching of the singlet oxygen in an aqueous medium. The introduction of lycopene, as well as beta-carotene in liposomes subjected to Fe(2+)-induced lipid peroxidation decreased the chemiluminescence (CL) intensity at the stage of CL slow flash, with no essential influence on the lag period. These data suggest that the effect of lycopene on lipid peroxidation was the result of its interaction with free radicals rather than chelating ferrous ions. The antiradical activity of lycopene was also confirmed by the method of luminol photochemiluminescence (PCL). Lycopene increased the PCL lag period (L) and decreased the PCL amplitude (A), which implies its antiradical and SOD-like activity in this system. 相似文献
118.
Shivani Dhall Manasvi Kumar Mehar Bhatnagar B.R. Mehta 《International Journal of Hydrogen Energy》2018,43(37):17921-17927
In the present work, role of palladium (Pd) and tin oxide (SnO2) nanoparticles (NPs) deposited on graphene has been investigated in terms of dual gas sensing characteristics of ethanol and H2 between two temperatures. The incorporation of nanoparticles into graphene has been observed which results a large change in the sensing response towards these gases. It is investigated that, incorporation of isolated Pd NPs on the graphene facilitates the room temperature sensing of H2 gas with fast response and recovery time whereas, isolated SnO2 NPs on graphene enables the detection of ethanol at 200 °C. However, combination of isolated Pd and SnO2 NPs on graphene shows improved sensitivity and good selectivity towards H2 and ethanol, usually not observed in chemiresistive gas sensors. Catalytic PdH interaction and corresponding change in work function of nanoparticles on hydrogenation resulting in modifications in electronic exchange between Pd, SnO2 and graphene are responsible for the observed behavior. These results are important for developing a new class of chemiresistive type gas sensor based on change in the electronic properties of the graphene and NPs interfaces. 相似文献
119.
LH Young Y Renfu R Russell X Hu M Caplan J Ren GI Shulman AJ Sinusas 《Canadian Metallurgical Quarterly》1997,95(2):415-422
BACKGROUND: Myocardial ischemia increases heart glucose utilization in vivo. However, whether low-flow ischemia leads to the translocation of glucose transporter (GLUT)-4 and/or GLUT-1 to the sarcolemma in vivo is unknown. METHODS AND RESULTS: In a canine model, we evaluated myocardial glucose metabolism in vivo and the distribution of GLUT-4 and GLUT-1 by use of immunoblotting of sarcolemma and intracellular membranes and immunofluorescence localization with confocal microscopy. In vivo glucose extraction increased fivefold (P < .001) and was associated with net lactate release in the ischemic region. Ischemia led to an increase in the sarcolemma content of both GLUT-4 (15 +/- 2% to 30 +/- 3%, P < .02) and GLUT-1 (41 +/- 4% to 58 +/- 3%, P < .03) compared with the nonischemic region and to a parallel decrease in their intracellular contents. Immunofluorescence demonstrated the presence of both GLUT-4 and GLUT-1 on cardiac myocytes. GLUT-1 had a more prominent cell surface pattern than GLUT-4, which was primarily intracellular in the nonischemic region. However, significant GLUT-4 surface labeling was found in the ischemic region. CONCLUSIONS: Translocation of the insulin-responsive GLUT-4 transporter from an intracellular storage pool to the sarcolemma occurs in vivo during acute low-flow ischemia. GLUT-1 is also present in an intracellular storage pool from which it undergoes translocation to the sarcolemma in response to ischemia. These results indicate that both GLUT-1 and GLUT-4 are important in ischemia-mediated myocardial glucose uptake in vivo. 相似文献
120.
实际工程应用中,需要对卫星信道参数进行测量跟踪。根据卫星漂移特点,建立了卫星信道参数测量跟踪模型,提出了一种基于卡尔曼滤波的测量跟踪方法。仿真结果表明,该方法可以有效跟踪卫星信道相对时延和相位的变化。 相似文献