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181.
The coincidence of neuronal stress induced by intoxication and an overexpression of amyloid precursor protein (APP) in the brains of children was examined. Brains of ten children accidentally intoxicated by poisonous mushroom were studied by means of immunohistochemical methods using monoclonal antibodies generated against different domains of APP and glial cell markers. Overexpression of APP was found in the brain neurons of all intoxicated children. Neurons were immunopositive with the antibodies generated against the middle (amyloid beta protein) domain of APP. No extracellular deposits were found in the tissue. Our results provided, for the first time, the evidence that overexpression of APP concomitant with the neuronal stress is age-independent phenomenon appearing not only in the brain of adults but in very young individuals as well. 相似文献
182.
矿井串联系统模糊可靠性理论的研究 总被引:1,自引:0,他引:1
矿井系统不仅具有随机性,而且同时也具有模糊性,在系统分析与设计过程中应同时考虑这两种不确定性因素的影响。文中提出了模糊故障、模糊功能、系统模糊运营状态和广义可靠度等概念,并在此基础上提出了求单元及串联系统的生产能力、营运费用、应急维修费用、修理时间和广义可靠度等指标的方法,建立了使系统平均生产能力最大的系统最优运营策略的数学模型。 相似文献
183.
184.
全金属反射光学系统结构的有限元分析 总被引:3,自引:1,他引:2
用有限元分析方法对全金属反射光学系统在各种受力状态下的变形、应力及固有频率做了全面的分析,并给出了结构多次优化后的分析结果。 相似文献
185.
X荧光光谱法测定不锈钢的研究 总被引:1,自引:0,他引:1
本文论述了X荧光光谱测定高铬钢和不锈钢的分析方法,用理论α系数校正基体效应和用谱线干扰系数L校正谱线重叠影响。方法准确度和精度令人满意,操作十分简便、快速。 相似文献
186.
The frequency modulation response and tuning dynamics of a two-section DFB laser are determined by carrier and thermal modulation of the active layer refractive index. In response to a step change in the injection current for switching between channels in a wavelength division multiplexed system, the optical frequency changes rapidly due to the carrier effect, and then slowly drifts toward a steady state value due to the thermal effect. For wavelength switched applications with heterodyne detection, the drifting of the optical frequency broadens the spectrum of the IF signal and may impose a limit on the time that the signal remains within the IF passband (residency time). The IF spectral broadening and residency time are investigated theoretically and experimentally. Based upon a minimum mean square error fit between experimental and theoretical FM responses, the dependence of the spectral broadening and residency time on the bias condition of the laser and the optical frequency switching interval is characterized 相似文献
187.
J G?uszek B Raszeja-Wanic I Stachowiak F Banaszak L Szcze?niak D Musialik T Kosicka A Tykarski A Boruczkowska A Sko?uda A Ma?aczyńska A Wichrowska K Rutz-Danielczak B Krasińska 《Canadian Metallurgical Quarterly》1996,96(6):570-576
Two groups of hypertensive patients: 137 responsive (on one or two drugs) and 162 resistant on antihypertensive treatment in the similar age were compared. Resistant patients (on three or more drugs) characterize by significantly higher body weight and BMI, longer history of hypertension, more frequent hypertension prevalance in family members and lower education. Level of triglycerides in resistant on antihypertensive treatment patients was significantly higher than in responsive patients. Insulin level in blood in 31 patients with essential hypertension was significantly higher than in 36 healthy persons and 20 patients with renovascular hypertension and resistant on antihypertensive therapy. In 14 patients with essential hypertension resistant to treatment insulin level one hour after oral glucose load was significantly (p < 0.01) higher than in 16 patients with essential hypertension responsive to antihypertensive treatment. 相似文献
188.
通过分析易结晶原料的性能特点,确立了合理的绒光釉配方及相应的工艺参数,探讨了釉料形成机理,研制出一种适合精陶及其它陶瓷产品的艺术釉-绒光釉。 相似文献
189.
本文根据刚体极限平衡分析原理,考虑各块体的力矩平衡和块间的嵌合作用,假定作用于块体的已知外力所产生的应力呈线性分布,推导出确定其作用力数值、方向和作用点,以及整体抗滑稳定安全系数的方法和公式。并通过实用研究了嵌合作用、分界面倾角等对反力分布和安全系数的影响,与常用方法的计算结果作了比较,说明本方法有较大的适用性,可应用于工程设计。 相似文献
190.
The coal filter cake is a product of fine coal after floatation which has an ash content of 7-13%, water content of 30±2%, and a particle size of less than 1 mm. The ash content was measured by the intensity of the single backscattered gamma-ray, and its accuracy is mainly dependent on the energy of the gamma-ray. The 238Pu low energy photon source is selected in this work. The energy of its gamma-ray is 15 keV, which can result not only in the best sensitivity, but also in the lowest contribution to the environment radiation. The root mean square deviation of the ash measurement is±0.33% (±1σ). 相似文献