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41.
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VT Za?tsev VV Bo?ko BI Peev EM Klimova NI Potapova FK Dib IA Taraban 《Canadian Metallurgical Quarterly》1996,(5-6):86-89
Based on a comprehensive analysis of findings from examination and surgical treatment of 196 patients with bleeding pyloroduodenal ulcers, it was found out that patients with concurrent helicobacteriosis of the stomach are prone to more unfavourable course of their illness, which fact is evidenced by a greater loss of blood and higher risk for bleeding recurrences. A classification is proposed by the authors, taking advantage of the data from endoscopic, microscopic and immunoenzymatic techniques, with the purpose of providing an assessment of degree of severity of helicobacteriosis of the stomach. 相似文献
43.
NI Gluck 《Canadian Metallurgical Quarterly》1996,19(1):41-47
Blood-borne cytokines enter the brain by transport across the blood-brain barrier (BBB) or by leakage through extracellular pathways at sites, such as circumventricular organs (CVOs), without a BBB. We used radioactively labeled albumin (T-Alb) to differentiate the relative contribution of transport and extracellular pathways to the passage of interleukin-1 alpha ([125I]IL-1 alpha) across the BBB. The major mechanism of entry for [125I]IL-1 alpha after intravenous (i.v.) injection was a saturable transport system with extracellular pathways accounting for only a small fraction of entry into brain. CVOs concentrated blood-borne [125I]IL-1 alpha in a saturable manner to a much greater extent than did the cerebral cortex and cerebellum, but accounted for less that 5% of total brain uptake. After intracerebroventricular (i.c.v.) injection, [125I]IL-1 alpha and T-Alb were concentrated in the CVOs, especially the median eminence, although CVOs contained less that 1% of the substances injected. Distribution after i.c.v. injection was largely due to diffusion and leakage through extracellular pathways. We conclude that after i.c.v. injection, leakage across extracellular pathways accounts for the small but concentrated amount of [125I]IL-1 alpha found in CVOs. After i.v. injection, transport across the BBB accounts for the majority of [125I]IL-1 alpha in brain. 相似文献
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45.
文章讨论了PAGER控制器芯片(ZQD021)的系统设计,该控制器内部集成了FLASH,SRAM,POCSAG协议解码器和嵌入式MCU CORE。重点分析了芯片的可测性设计(DFT),内嵌FLASH设计,低功耗设计,其设计方法和思路对消费类和嵌入式控制芯片的设计有一定的借鉴意义。 相似文献
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NI Dolvik 《Canadian Metallurgical Quarterly》1994,18(4):281-288
Of 508 four-year-old coldblooded trotters examined for carpitis, 135 (27%) had the condition. Thirty horses had unilateral carpitis on the left frontlimb, 52 on the right frontlimb and 53 had bilateral carpitis. Of these horses, 105 were stallions, 135 were geldings and 269 were mares. The prevalence of carpitis in these three groups was 25%, 25% and 28%, respectively. Information was obtained on the training regimes in four periods of the life of 378 horses. The odds ratios for the training variables were of the same order in all four periods. In logistic regression analyses on the training variables for the first period for the variable percentage of carpitis within each progeny group (sire index), the odds ratio corresponding to a 10% increase in sire index was 1.7 (1.4, 2.1) (95% confidence interval of the odds ratio). The odds ratios for leaving the horses out in a paddock, walking in a jogcart and fast training, or not in each case, were 0.4 (0.2, 0.9), 2.5 (1.2, 5.3) and 2.0 (0.9, 4.4), respectively. This implies a decreased risk of developing carpitis for horses left out in a paddock as a two-year-old, and a 2.5 and 2.0 times increased risk of carpitis occuring in horses exposed to walking in a jogcart and fast training, respectively. Information on the feeding regimes during the first, second and third year collected by a questionnaire revealed no association with carpitis beyond that which could be ascribed to chance. The rations offered were within normal ranges except for calcium, which was below recommended levels. 相似文献
48.
AR Reilein IS Tint NI Peunova GN Enikolopov VI Gelfand 《Canadian Metallurgical Quarterly》1998,142(3):803-813
We used melanophores, cells specialized for regulated organelle transport, to study signaling pathways involved in the regulation of transport. We transfected immortalized Xenopus melanophores with plasmids encoding epitope-tagged inhibitors of protein phosphatases and protein kinases or control plasmids encoding inactive analogues of these inhibitors. Expression of a recombinant inhibitor of protein kinase A (PKA) results in spontaneous pigment aggregation. alpha-Melanocyte-stimulating hormone (MSH), a stimulus which increases intracellular cAMP, cannot disperse pigment in these cells. However, melanosomes in these cells can be partially dispersed by PMA, an activator of protein kinase C (PKC). When a recombinant inhibitor of PKC is expressed in melanophores, PMA-induced pigment dispersion is inhibited, but not dispersion induced by MSH. We conclude that PKA and PKC activate two different pathways for melanosome dispersion. When melanophores express the small t antigen of SV-40 virus, a specific inhibitor of protein phosphatase 2A (PP2A), aggregation is completely prevented. Conversely, overexpression of PP2A inhibits pigment dispersion by MSH. Inhibitors of protein phosphatase 1 and protein phosphatase 2B (PP2B) do not affect pigment movement. Therefore, melanosome aggregation is mediated by PP2A. 相似文献
49.
非下采样Contourlet变换(Nonsubsampled contourlet transform,NSCT)采用非抽样金字塔结构和非抽样方向滤波器组构成,具有Contourlet变换所不具备的平移不变性、较高冗余度等优良特性,而且能够克服伪吉布斯现象。图像经过非下采样Contourlet变换后分解成多尺度、多方向的细节信息,这些细节信息代表了图像不同频带不同方向的特征,这就简化了系数之间的关系。基于学习的超分辨率重建算法具有整体的预测性,将非下采样Contourlet变换和基于学习的算法相结合,在一定程度上提高训练精度。针对指纹图像的实验证明该算法具有良好的性能,重建的图像纹理性细节信息较好,基本保持了原指纹图像的特征点,更接近于原始的高分辨率图像。 相似文献
50.
在介绍半导体热熔型塑胶封装工艺流程的基础上,对于采用欧姆龙NJ系列高性能多功能一体化新型控制器的芯片封装设备研发,给出关键论题的多方案创新性研讨. 相似文献