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991.
Atorvastatin calcium is an HMG-coenzyme A (CoA) reductase inhibitor that was approved by the Food and Drug Administration on December 17, 1996. Like other such agents, it inhibits the action of HMG-CoA reductase and thereby decreases endogenous cholesterol synthesis, leading to a decrease in circulating low-density lipoprotein cholesterol. In addition to its effect on lipoprotein profile, atorvastatin reduces triglycerides to a greater extent than other HMG-CoA reductase inhibitors. These actions occur in a dose-dependent fashion. The adverse effect profile is similar to that of other agents in this class. Indications for atorvastatin include primary hypercholesterolemia as well as other lipid disorders. 相似文献
992.
焦化洗氨洗萘水氰浓度高、酚浓度低、水量大 ,若直接进行生化处理会即刻杀死微生物 ,萍乡钢铁有限责任公司研究开发了铁盐法脱氰预处理工艺 ,但处理后废水中氰浓度仍在 10~ 18mg/L ,对于脱酚细菌仍属高浓度。根据对活性污泥的驯化过程对脱酚活性污泥影响的研究 ,得出适于细菌生存繁殖的运行参数为磷酸二氢钠加入量 12kg/d以上 ,葡萄糖 9kg/d以上 ,自沉污泥指数约 2 0mL/10 0mL ,回流污泥指数约 30mL/10 0mL ,温度为 2 5~35℃。 相似文献
993.
Min B.G. Kim H.C. Choi J.W. Ryu G.H. Seo K.P. Rho J.R. Ahn H. Kim S.W. Diegel P.D. Olsen D.B. 《IEEE transactions on bio-medical engineering》1990,37(12):1195-1200
A new type of electromechanical total artificial heart (TAH) based on circular rolling-cylinder mechanism was developed to overcome critical problems in motor-driven artificial hearts such as large size and difficulties in fitting the heart to atrial remnants and arterial vessels. Its performance and reliability were evaluated in mock circulation and in an animal implant experiment. The total weight and volume of the pump is 650 g and 600 mL, respectively. This new pump was implanted in a calf for total heart replacement and 96 h of survival was achieved. The whole system, including pump, controller, and control algorithm performed well enough to improve the prospect of eventual clinical application of our TAH system. 相似文献
994.
995.
996.
Jung‐Bae Jun Min‐Su Seo Seong‐Heun Cho Jin‐Gyu Park Jee‐Hyun Ryu Kyung‐Do Suh 《应用聚合物科学杂志》2006,100(5):3801-3808
In the electroless plating process, to omit a sensitizing process with SnCl2, we utilized amino‐functional groups on polymer particles. At first, highly monodisperse functional polymer particles could be prepared by a two‐step seeded polymerization of styrene, divinylbenzene, and glycidyl methacrylate. Then, surface epoxy‐functional groups were converted to amino‐functional groups by treating the particles with a diamine. By using these surface amino functionalities, we tried to prepare uniformly metal‐coated monodisperse polymer particles by electroless plating method. The constituents of an electroless nickel solution bath are nickel salt, a reducing agent, suitable complexing agents, and stabilizers. And the metal thickness was simply controlled by changing the loading amount of substrate polymer particles. Morphological observation of nickel‐plated polymer particles was conducted by using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The structural composition of plated nickel was also investigated. Most of all, the function and the efficiency of the amino‐functional group of polymer particles as a polymeric ligand for metal binding was elucidated. From all observations, it was evident that in the electroless metal plating process without any sensitization step, the deposition of metal clusters on substrate particles is largely dependent upon the particle surface functionality. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3801–3808, 2006 相似文献
997.
SA Castleden H Chong I Garcia-Ribas AA Melcher G Hutchinson B Roberts IR Hart RG Vile 《Canadian Metallurgical Quarterly》1997,8(17):2087-2102
The herpes simplex virus-thymidine kinase/ganciclovir (HSVtk/GCV) system produces both direct and immune-mediated tumor cell killing. Here, we compare the efficacy of HSVtk/GCV with cytokines, alone and in combination, on the tumorigenicity and immunogenicity of B16 cells. With respect to single gene modifications, only HSVtk/GCV, or high-level interleukin-2 (IL-2) secretion, completely prevented tumor growth, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) generated the best levels of long-term systemic protection. To augment both local killing and immune activation, we constructed bicistronic constructs that express HSVtk and a cytokine within the same cell. Co-expression of HSVtk with IL-2 or GM-CSF enhanced the local antitumor activity of any gene alone. In a tumor-prevention model, HSVtk killing, in an environment preprimed with GM-CSF, generated the best long-term immune protection. However, in a short-term therapy model, continued IL-2 expression was most effective against 3-day established tumors. This probably reflects differences in the activities of IL-2 and GM-CSF in generating short-term, nonspecific immune stimulation compared to long-term immunological memory, respectively. As a prelude to in vivo delivery experiments, we also demonstrated that these bicistronic cassettes can be packaged normally into retroviral (5 x 10(5) virus/ml from pooled populations) and adenoviral vectors (5 x 10(9) virus/ml) and function as predicted within virally infected cells. This family of bicistronic vectors can be used to stimulate synergy between suicide and cytokine genes, overcomes the problems of delivering two genes on separate vectors, and should allow easier preparation of vectors for the delivery of multiple genes to patients' tumor cells. 相似文献
998.
In this paper, an intelligent controller capable of static balancing as well as dynamic balancing of a pole mounted on a motorized robot is designed and developed. The brain of the intelligent controller lies in the Fuzzy Inference System, which receives as its input displacement, velocity and acceleration information. An embedded instrumentation system onboard the robot measures the displacement of the robot and the angle of inclination of the pole from the vertical position. For static balancing, the controller needs to maintain the pole in an upright position while the robot is free to move on a flat surface. For dynamic balancing, the robot needs to balance the pole while performing transitions up and down a ramp. Furthermore, the robot needs to steer itself back to the center to prevent it from falling off the ramp. 相似文献
999.
5万m~2地下特大型支撑爆破拆除 总被引:4,自引:1,他引:3
介绍了在复杂环境下爆破拆除一地下特大钢筋混凝土支撑的技术难点。由于合理选取爆破参数,采取孔内高段、孔外低段毫秒微差起爆网路,安全防护采取覆盖、近体、保护性三种措施,有效地阻止了飞石对周围建筑物的损害,并对爆破可能产生的危害进行了科学验算,最后分多次爆破圆满完成拆除任务。 相似文献
1000.
Observation of the OH induced absorption loss near 1.39 μm in optical fibres tapered using a flame brushing technique is reported. The induced loss is experimentally analysed in terms of tapering conditions, fibre type, and annealing conditions. Impacts of the OH induced loss on fused taper fibre devices are discussed 相似文献