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991.
Tingting Shi Hisakazu Iwama Koji Fujita Hideki Kobara Noriko Nishiyama Shintaro Fujihara Yasuhiro Goda Hirohito Yoneyama Asahiro Morishita Joji Tani Mari Yamada Mai Nakahara Kei Takuma Tsutomu Masaki 《International journal of molecular sciences》2021,22(23)
Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related deaths worldwide. Sorafenib has been used as a first-line systemic treatment for over a decade. However, resistance to sorafenib limits patient response and presents a major hurdle during HCC treatment. Lenvatinib has been approved as a first-line systemic treatment for advanced HCC and is the first agent to achieve non-inferiority against sorafenib. Therefore, in the present study, we evaluated the inhibition efficacy of lenvatinib in sorafenib-resistant HCC cells. Only a few studies have been conducted on this topic. Two human HCC cell lines, Huh-7 and Hep-3B, were used to establish sorafenib resistance, and in vitro and in vivo studies were employed. Lenvatinib suppressed sorafenib-resistant HCC cell proliferation mainly by inducing G1 cell cycle arrest through ERK signaling. Hep-3B sorafenib-resistant cells showed partial cross-resistance to lenvatinib, possibly due to the contribution of poor autophagic responsiveness. Overall, the findings suggest that the underlying mechanism of lenvatinib in overcoming sorafenib resistance in HCC involves FGFR4-ERK signaling. Lenvatinib may be a suitable second-line therapy for unresectable HCC patients who have developed sorafenib resistance and express FGFR4. 相似文献
992.
Process-induced residual stresses may cause cracking in thick-walled multi-layered CFRP pipes during the curing of the pipes, significantly affecting the ultimate structural performance. Several factors influence the amount of the residual stresses, such as thermal and elastic properties of CFRP, and stacking sequences and dimensions of pipes. This paper deals with the optimum design of thick-walled multi-layered CFRP pipes by minimising the process-induced residual stresses under some constraints of structural stiffnesses. An analytic model based on quasi-static thermoelasticity is adopted for the calculation of the residual stresses in the multi-layered CFRP pipes. The numerical results of optimisation show that, in the case of cross-ply pipes, the residual stresses can be reduced to a certain level by controlling ply thicknesses. However, in real process conditions, the optimised pipes are susceptible to cracking because the transverse residual stress is still large in a strength-based sense. To further suppress the residual stresses, the effects of stacking sequence, wall thickness and axial pre-tension on the optimum solutions are carefully examined. 相似文献
993.
Shinichi Taira Osamu Takeda Yuichi Otsu Hideki Katagiri 《International Journal of Satellite Communications and Networking》1998,16(3):131-136
An on-board processor makes efficient use of the channel capacities in a satellite communications system employing multibeam technology, and an on-board processor has been developed for the Engineering Test Satellite VIII (ETS-VIII), which is the experimental satellite for a multibeam mobile satellite communications system. The multicarrier time division multiple access (MC-TDMA) system used in this communications system, however, sometimes causes internal congestion in the on-board processor. This paper describes the results of computer simulation studies of the traffic capacity obtained using three baseband switching methods and also describes the results of studies of the on-board processor design for each of the methods. The computer simulation results indicate that the probability of internal congestion due to the TDMA system is very small when the simultaneous-slot switching method is used, and the design study results reveal that an on-board processor using the simultaneous-slot switching method will be compact and lightweight and will consume little power. © 1998 John Wiley & Sons, Ltd. 相似文献
994.
Kyoko Makino Kazuo Nishimura Hideki Hayashi Masahiko Arai 《Electrical Engineering in Japan》1997,118(4):27-34
This paper proposes a new method of optimizing the operation of a power transmission system, based on a structured neural network. Because the structured neural network is built by prewiring, the network construction time is very short. Simulations of transmission loss of reduction have been carried out. It is shown that the optimization performance of the proposed method is satisfactory in practice. © 1997 Scripta Technica, Inc. Electr Eng Jpn. 118 (4): 27–34, 1997 相似文献
995.
Tungsten carbide and tantalum carbide were sprayed onto substrates of mild steel by the electrothermally exploded powder spray
(ELTEPS) process. High-speed x-ray radiography revealed that tungsten-carbide jets of molten particles guided inside a nozzle
exhibited denser flow than unguided jets at the substrate. The velocity of the jet was approximately 800 m/s at the early
stage of jetting. The ceramic coatings obtained from the guided spray consisted of carbides of a few to tens of micrometers
in size, which were saturated by the base metal up to the top of the coating. The coatings exhibited diffusion of the sprayed
ceramics and base metal at the interface of the deposit and substrate. The enhancement of the jet flow formed a microstructure
of the ceramic coating, which was saturated by the base metal even without post heat treatment. 相似文献
996.
An experimental study was performed to determine the natural-convection heat transfer characteristics of horizontal cylinders placed in a horizontal line in air. Local heat transfer coefficients were measured for three- and nine-cylinder arrays in various cylinder-spacing arrangements. As a result, it was found that there were no major differences in heat transfer coefficient among cylinders, other than for the array-edge cylinders. The mean value of all cylinders was clearly different from that of the array-edge cylinders. Based on a simple consideration for the effect of cylinder-spacing on heat transfer coefficient, correlation equations were proposed for each kind of heat transfer coefficient mentioned above. All the experimental heat transfer coefficients were expressed well by these equations. © 1997 Scripta Technica, Inc. Heat Trans Jpn Res, 25(6): 410–419, 1996 相似文献
997.
Lina Zhang Xiaojuan Xu Mei Zhang Jinghua Chen Diya Meng Liwei Ren Hideki Iijima 《应用聚合物科学杂志》2000,75(8):1083-1088
Erwinia (E) gum, a stabilizer and thickening agent of food, is composed of glucose, fucose, galactose, and glucuronic acid (1 : 0.1 : 0.05 : 0.3 by molar ratio). The apparent weight‐average molecular weight Mw and intrinsic viscosity [η] in 0.2 M NaCl aqueous solution were measured to be 7.83 × 105 and 268 mL g−1, respectively, by light scattering and viscometry. The aggregation behavior of E gum in aqueous solution was investigated by gel permeation chromatography (GPC) and dynamic light scattering. The results showed that 7.5% E gum exists as an aggregate, whose diameter is 12 times greater than single‐stranded chain, in aqueous solution at 25°C, and the aggregates' content decreased with increasing temperature or decreasing polymer concentration. The aggregates at higher temperature were more readily broken than in exceeding dilute solution. GPC analysis proved that a significant shoulder, corresponding to a fraction of higher molecular weight due to chain aggregation, appeared in the chromatogram of E gum in 0.05 M KH2PO4/5.7 × 10−3 M NaOH aqueous solution (pH 6.0) at 35°C, and decreased with increasing temperature, finally disappeared at 90°C. The disaggregation process of E gum in aqueous solution can be described as follows: with increasing temperature, large aggregates first were changed into the middle, then disrupted step by step into single‐stranded chains. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1083–1088, 2000 相似文献
998.
A density functional theory (DFT) method (periodic DMol3) with full geometry optimization was used to investigate the adsorption of nitrogen-containing heterocycles such as 4-t-butylpyridine (TBP) and imidazole on a TiO2 anatase (1 0 1) surface. Negative shifts of the TiO2 Fermi level by N-containing heterocycle adsorption were observed. Imidazole adsorption shifted the Fermi level of TiO2 more negatively than TBP. This shift corresponded to the enhancement of the open-circuit photovoltage (Voc) and the reduction of the short-circuit photocurrent density (Jsc) in a dye-sensitized TiO2 solar cell. We are the first to theoretically discover a TiO2 band shift upon N-containing heterocycles adsorption, and have successfully related this shift to the effect as an additive in an electrolyte solution on dye-sensitized solar cell performance. 相似文献
999.
The objective of this study is to contribute to widespread use of earth-to-air heat exchangers by proposing a design procedure. In this paper, it is discussed the design method when an earth-to-air heat exchanger system consists of multiple pipes with a close arrangement.A numerical model for this multi-cool/heat tube system was developed and it was verified by field measurements. With taking into account the thermal interference between tubes, the heat transfer performance was evaluated under various design conditions such as number of tubes, arrangement interval, air velocity and length, and soil properties. Based on these results, an estimation method for the heat transfer rate for the multi-cool/heat tube system is proposed. 相似文献
1000.
luthaluctionA high spatial resoluhon, tWo components LaserDoPPler Velocimetry (LDV) has been used for ~fencemeasurements with a high data rate in a cylindrical pipeflow of water In this stUdy, LDV measurements of thetWo velocity componentS in the streamwise ~on andin the radial direchon are performed. As the probe deteCtsthe scattered lights from the seeding particle, the LDVmeasures rather the velocity Of the seeding particle itselfthan the flow velocity. Provided that seeding pwhcles… 相似文献