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91.
本文介绍了模糊技术的发展和现状,以及在相关领域中的应用情况,并且讨论了模糊技术在我国的产业化方向等问题。 相似文献
92.
LI Tsao B Ladenheim AM Andrews CC Chiueh JL Cadet TP Su 《Canadian Metallurgical Quarterly》1998,287(1):322-331
Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical. 相似文献
93.
Low cardiac output after open heart operations in neonates and infants carries a high mortality. Delayed sternal closure may be life-saving but may prolong hospital stay and increase costs. To circumvent these issues, we shaped homograft bone and interposed it between the sternal edges to allow primary wound closure in 2 pediatric patients. Midterm results are satisfactory. 相似文献
94.
The phosphorylation of glucose to glucose-6-phosphate, catalyzed by hexokinase, is the first committed step in glucose uptake into skeletal muscle. Two isoforms of hexokinase, HKI and HKII, are expressed in human skeletal muscle, but only HKII expression is regulated by insulin. HKII messenger RNA, protein, and activity are increased after 4 h of insulin infusion; however, glucose uptake is stimulated much more rapidly, occurring within minutes. Studies in rat muscle suggest that changes in the subcellular distribution of HKII may be an important regulatory factor for glucose uptake. The present studies were undertaken to determine if insulin causes an acute redistribution of HKII activity in human skeletal muscle in vivo. Muscle biopsies (vastus lateralis muscle) were performed before and at the end of 30 min insulin infusion, performed using the euglycemic clamp technique. Muscle biopsies were subfractionated into soluble and particulate fractions to determine if insulin acutely changes the subcellular distribution of HKII. Insulin decreased HKII activity in the soluble fraction from 2.20 +/- 0.31 to 1.40 +/- 0.18 pmoles/(min[chempt]micrograms) and increased HKII activity in the particulate fraction from 3.02 +/- 0.46 to 3.45 +/- 0.46 pmoles/(min[chempt]micrograms) (P < 0.01 for both). These changes in HKII activity were correlated with changes in HKII protein, as determined by immunoblot analysis (r = 0.53, P = 0.05). Insulin had no effect on the subcellular distribution of HKII activity, which was primarily restricted to the soluble fraction. These studies are consistent with the conclusion that, in vivo in human skeletal muscle, insulin changes the subcellular distribution of HKII within 30 min. 相似文献
95.
96.
In this paper, a hybrid integrator backstepping controller is proposed for robotic manipulators actuated with brushless DC motors in the presence of arbitrary uncertain inertia parameters of the manipulator and the electrical parameters of the actuators. The main features are: 1) the design, requiring at most the joint velocities and stator currents feedback; 2) the semiglobal asymptotic stability of the controller being established in the Lyapunov sense; and 3) suitability of the scheme for multijoint robots. Simulation results are included to demonstrate the tracking performance. 相似文献
97.
随着载有各种新型传感器的卫星相继发射升空,不同传感器之间的相互比较成了一个研究热点。首先从传感器的轨道特征、光谱范围等方面对IRS-P6 LISS-3和Landsat-5 TM进行了机理方面的对比分析,选取3对同日过空的遥感影像,研究了IRS-P6 LISS-3和Landsat-5 TM遥感数据在可见光-近红外、短红外各对应光谱波段之间的关系,建立TM和LISS-3各波段之间的相互转换公式,与Chander等提出的转换公式进行对比分析。结果表明:实际TM和模拟TM多光谱数据之间具有较强的相关关系,决定系数R2均大于0.97;模拟TM与实际TM的水体指数(MNDWI)和归一化植被指数(NDVI)空间散点分布和实际LISS-3与实际TM的空间散点分布相比,具有更强的相关关系,其决定系数R2有一定提高,散点分布趋于对称。因此,所求的关系转换方程具有较高的精度和有效性,效果优于Chander等提出的转换公式。 相似文献
98.
苏同建 《计算机光盘软件与应用》2012,(3):26+25
企业信息化作为国民经济信息化的基础,是当前推进国民经济信息化的重中之重。伴随全球信息化浪潮,我国煤矿企业信息化进程不断向深度和广度双向推进,但依然存在一些不尽人意的地方。本文首先分析了煤矿企业信息化的现状和制约信息化的原因,在此基础生展望了煤矿企业信息化的发展方向。 相似文献
99.
To clarify some of the solid-state aspects of cold fusion in deuterated transition metal electrodes, we have carried out first-principles self-consistent total energy calculations for various configurations of atomic and diatomic deuterium inside fcc palladium. We find that the stability of the Pd+D system is controlled by the relative position of the deuterium-inducedantibonding level with respect to the Fermi energy. The equilibrium D-D distance in dense PdD
up to =3 is found to be much larger than the free space value. The calculated Born-Oppenheimer energy surface of diatomic D2 in crystalline palladiuim is shown to have but metastable local minima whose internuclear separation is at least 0.2 Ålarger than that of the isolated D2 molecule. We conclude that D2 incrystalline Pd will have a substantially lower tunneling probability than hitherto thought and that explanation for fusion mechanisms should be sought elsewhere. 相似文献
100.
Entity linking is a fundamental task in natural language processing. The task of entity linking with knowledge graphs aims at linking mentions in text to their correct entities in a knowledge graph like DBpedia or YAGO2. Most of existing methods rely on hand‐designed features to model the contexts of mentions and entities, which are sparse and hard to calibrate. In this paper, we present a neural model that first combines co‐attention mechanism with graph convolutional network for entity linking with knowledge graphs, which extracts features of mentions and entities from their contexts automatically. Specifically, given the context of a mention and one of its candidate entities' context, we introduce the co‐attention mechanism to learn the relatedness between the mention context and the candidate entity context, and build the mention representation in consideration of such relatedness. Moreover, we propose a context‐aware graph convolutional network for entity representation, which takes both the graph structure of the candidate entity and its relatedness with the mention context into consideration. Experimental results show that our model consistently outperforms the baseline methods on five widely used datasets. 相似文献