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41.
The number of diabetes mellitus (DM) patients is increasing, and stroke is deeply associated with DM. Recently, neuroprotective effects of glucagon-like peptide-1 (GLP-1) are reported. In this study, we explored whether liraglutide, a GLP-1 analogue exerts therapeutic effects on a rat stroke model. Wistar rats received occlusion of the middle cerebral artery for 90 min. At one hour after reperfusion, liraglutide or saline was administered intraperitoneally. Modified Bederson’s test was performed at 1 and 24 h and, subsequently, rats were euthanized for histological investigation. Peripheral blood was obtained for measurement of blood glucose level and evaluation of oxidative stress. Brain tissues were collected to evaluate the level of vascular endothelial growth factor (VEGF). The behavioral scores of liraglutide-treated rats were significantly better than those of control rats. Infarct volumes of liraglutide-treated rats at were reduced, compared with those of control rats. The level of derivatives of reactive oxygen metabolite was lower in liraglutide-treated rats. VEGF level of liraglutide-treated rats in the cortex, but not in the striatum significantly increased, compared to that of control rats. In conclusion, this is the first study to demonstrate neuroprotective effects of liraglutide on cerebral ischemia through anti-oxidative effects and VEGF upregulation.  相似文献   
42.
Radiation-induced bulk polymerization of ethylene was carried out with use of a pilot plant with a 10 liter reactor at pressures of 225–400 kg/cm2, temperatures of 30–95°C, ethylene feed rates of 5–28 kg/hr, and dose rate of 3.8 × 105 rad/hr. Characteristics of the process are mild polymerization conditions and capability of producing medium density polyethylene in powder form. The spacetime yield and molecular weight of polymer were in the range of 3.5 to 13.1 g/liter hr and 2.2 × 104 to 14 × 104, respectively. The space-time yield increased with mean residence time and 2.4 powders of pressure, and decreased with temperature. Molecular weight changed similarly with the reaction conditions. These results were consistent with those of the bench plant experiment and the scale effect was small. Polymer deposit to the reactor wall limited a period of continuous operation of the plant. The amount of deposited polymer was increased with the square of reaction time. The rate of polymer deposit was proportional to polymer concentration and to the cube of pressure. The polymer deposit cannot be solved in the bulk process.  相似文献   
43.
We have produced thick-foil and fine-pitch gas electron multipliers (GEMs) using a laser etching technique. To improve production yield we have employed a new material, liquid crystal polymer, instead of polyimide as an insulator layer. The effective gain of the thick-foil GEM with a hole pitch of , a hole diameter of , and a thickness of reached a value of 104 at an applied voltage of 720 V. The measured effective gain of the thick-foil and fine-pitch GEM ( pitch, diameter, and thick) was similar to that of the thick-foil GEM. The gain stability was measured for the thick-foil and fine-pitch GEM, showing no significant increase or decrease as a function of elapsed time from applying the high voltage. The gain stability over 3 h of operation was about 0.5%. Gain mapping across the GEM showed a good uniformity with a standard deviation of about 4%. The distribution of hole diameters across the GEM was homogeneous with a standard deviation of about 3%. There was no clear correlation between the gain and hole diameter maps.  相似文献   
44.
Simplified procedure for preparation of35S-labeled brain sulfatide   总被引:1,自引:0,他引:1  
A simplified procedure for the preparation of35S-labeled brain cerebroside sulfates has been developed. The labeled sulfatides are synthesized in vivo after intracerebral administration of inorganic35S-sulfate in developing rats. The animals are sacrificed three days later and brain homogenates extracted with chloroform-methanol. The extract is subjected to mild alkaline treatment and washed with water. The organic phase is chromatographed on triethylaminoethyl-cellulose from which sulfatides are eluted with chloroform-methanol containing potassium acetate. Radioactive fractions are pooled, concentrated, and potassium acetate removed by dialysis against water. Alternatively, salts are removed by passing radioactive fractions through Sephadex G-25. After evaporating to near dryness, the radioactive cerebroside sulfates are dissolved in a small volume of chloroform-methanol and stored at −20 C. The35S-sulfatides are essentially free of lipid contaminants, and 97% of the radio-activity corresponds with sulfatides on chromatographic analysis.  相似文献   
45.
In this study, the flow dynamics of a Taylor–Couette flow with an axial distribution of temperature was experimentally investigated. The flow can be classified into three patterns based on the balance between the centrifugal force and the buoyancy. If the buoyancy is dominant, global heat convection is observed instead of Taylor vortices (Case I). When the buoyancy is comparable to the centrifugal force, the Taylor vortices and global heat convection appear alternately (Case II). If the centrifugal force is sufficiently high to suppress the buoyancy, stable Taylor vortices are observed (Case III). The characteristics of the mixing/diffusion are investigated by conducting a decolorization experiment on a passive tracer. In Case II, the tracer is rapidly decolorized in the presence of the global heat convection instead of the Taylor vortices. This result implies that the interaction between the centrifugal force and the buoyancy would induce an anomalous transport. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1075–1082, 2018  相似文献   
46.
Complete decomposition of perfluorooctanoic acid (PFOA) at a concentration of 41.4 mg/L and perfluorooctane sulfonate (PFOS) at a concentration of 60 mg/L in water was successfully completed by DC plasma within oxygen bubbles. PFOA and PFOS were decomposed completely after 3‐h operation and 8‐h operation, respectively. The decomposition efficiency was evaluated by measuring the amounts of fluorine ions that were detached from PFOA and PFOS in the solution. As indicated by the measurement of LC/MS, the main byproducts generated during the plasma treatment turned out to be perfluorocarboxylic acids. For practical application, 2‐parallel operation of DC plasma was also demonstrated as a basic technology for a large capacity reactor. The decomposition efficiency of 2‐parallel operation was at the same level as that of single operation.  相似文献   
47.
A lithium (Li) vapor injector for boundary control has been developed. A diverter covered with lithium is expected to reduce particle recycling. Recycling reduction is considered to be one of the triggers for the L-H transition. In this paper, the method of lithium dispersion is investigated under the assumption that the experiment is carried out in the Large Helical Device in National Institute for fusion Science, Japan (LHD). A performance test is performed on a prototype of the vapor injector. The amount of injected lithium was approximately 1% of the value expected from the vapor pressure data, due to the generation of lithium oxide. It is also found that nozzle temperature is quite important to suppress the Li dispersion.  相似文献   
48.
Owing to the explosive increase in Internet traffic, increasing the throughput and energy efficiency of core routers is an important issue for future internet. Accessing the ternary content addressable memory (TCAM) in a core router can significantly degrade its throughput and energy efficiency owing to its low operating frequency and power consuming operations. To improve the throughput and energy‐efficiency of core routers, packet processing caches (PPCs) can be potentially used. PPCs can reduce the number of TCAM accesses by storing the TCAM lookup results in a fast and low‐energy cache memory and reusing them to process subsequent packets. To enhance the PPC performance, it is important to reduce the number of PPC misses. However, the PPC miss rate of the state‐of‐the‐art PPC is still high owing to its small capacity. In this study, we propose an effective cache replacement policy, called elevator cache (ELC) to improve the PPC miss rate. Our simulation results showed that the 8‐way ELC, which can be implementable at low hardware cost, reduced the number of PPC misses by 17.1% and 5.67% in comparison to the 4‐way least recently used (LRU) and the 4‐way ELC, respectively. Consequently, it was found that the 8‐way ELC can achieve a 1.21 times higher throughput (560 Gbps) while consuming 83% energy in comparison to conventional PPCs.  相似文献   
49.
We prototyped phase-change (PC) channel transistors and demonstrated two functions of nonvolatile memory and channel current control. We have developed prototype transistors that use a PC channel instead of a silicon channel. The PC material of a Ge2Sb2Te5 thin film with a thickness of 50 nm was used. We demonstrated a memory function whereby we achieved a reversible change between the crystalline and amorphous phases by applying a source-drain (SD) voltage for Joule heating. In the experiment, the applied voltages for PC between amorphous and crystalline phases were from 5 to 8 V. Control of the channel current was realized by applying a gate bias. The SD current was suppressed to less than 1/20 of that at a gate bias of -3 V by applying a gate bias of 0-3 V  相似文献   
50.
Developing methods to determine cell type and cell state has been a significant challenge in the field of cancer diagnosis as well as in typing and quality verification for cultured cells. Herein, we report a cell profiling method based on binding interactions between cell-surface sugar-chain-binding proteins and sugar-chain-immobilized fluorescent nanoparticles (SFNPs), together with a method for cell typing and cell quality verification. Binding profiles of cells against sugar chains were analyzed by performing flow cytometry analysis with SFNPs. Discrimination analysis based on binding profiles could classify cell type and evaluate the quality of cultured cells. By applying our method to differentiated cells originating from conventional cell lines and also to mouse embryotic stem cells, we could detect the cells before and after differentiation. Our method can be utilized not only for the biofunctional analysis of cells but also for diagnosis of cancer cells and quality verification of cultured cells.  相似文献   
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