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排序方式: 共有636条查询结果,搜索用时 15 毫秒
11.
Masashi Ishikawa Masae Iwasaki Hailin Zhao Junichi Saito Cong Hu Qizhe Sun Atsuhiro Sakamoto Daqing Ma 《International journal of molecular sciences》2021,22(9)
Inhalational anesthetics was previously reported to suppress glioma cell malignancy but underlying mechanisms remain unclear. The present study aims to investigate the effects of sevoflurane and desflurane on glioma cell malignancy changes via microRNA (miRNA) modulation. The cultured H4 cells were exposed to 3.6% sevoflurane or 10.3% desflurane for 2 h. The miR-138, -210 and -335 expression were determined with qRT-PCR. Cell proliferation and migration were assessed with wound healing assay, Ki67 staining and cell count kit 8 (CCK8) assay with/without miR-138/-210/-335 inhibitor transfections. The miRNA downstream proteins, hypoxia inducible factor-1α (HIF-1α) and matrix metalloproteinase 9 (MMP9), were also determined with immunofluorescent staining. Sevoflurane and desflurane exposure to glioma cells inhibited their proliferation and migration. Sevoflurane exposure increased miR-210 expression whereas desflurane exposure upregulated both miR-138 and miR-335 expressions. The administration of inhibitor of miR-138, -210 or -335 inhibited the suppressing effects of sevoflurane or desflurane on cell proliferation and migration, in line with the HIF-1α and MMP9 expression changes. These data indicated that inhalational anesthetics, sevoflurane and desflurane, inhibited glioma cell malignancy via miRNAs upregulation and their downstream effectors, HIF-1α and MMP9, downregulation. The implication of the current study warrants further study. 相似文献
12.
Hirosuke Oku Jyutaro Shudo Kunio Mimura Akinori Haratake Junichi Nagata Isao Chinen 《Lipids》1995,30(2):169-172
A neutral lipid class was isolated by thin-layer chromatography from the skin surface lipids of the hairless mouse. The fraction
migrated faster than triglycerides and had a migration rate similar to that of diacyl alkanediols (diester wax). Upon deacylation,
however, the long-chain diols were identified as 1-alkylglycerol ethers based on their chromatographic properties and on the
mass spectra of their nicotinylidene derivatives. Thus, the skin lipid fraction was identified as 1-O-alkyl-diacylglycerol. The alkyl moieties were all saturated and even-numbered and ranged in chainlength from C16 to C22 with 1-O-hexadecylglycerol amounting to 34% of the total glycerol ether moieties. The fatty acids derived from this lipid fraction
were mostly monoenoic with chainlengths ranging from C16 to C24. The major acyl component was eicosenoic acid (20∶1) representing 61% of the total fatty acids. 相似文献
13.
Takatoshi Tsujimura Junichi Fukawa Kiyoshi Endoh Yuuji Suzuki Kazuhiko Hirabayashi Takahiro Mori 《Journal of the Society for Information Display》2014,22(8):412-418
To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10? 6 order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film. 相似文献
14.
Sittidej Teekateerawej Junichi Nishino Yoshio Nosaka 《Journal of Applied Electrochemistry》2005,35(7-8):693-697
Two kinds of porous ceramic disks, having through-holes with diameters of 0.1 and 0.05 mm, were coated with TiO2 using two different starting solutions: titanyl(IV)acetylacetonate and a commercial titania sol (STS-01). The morphology
of these porous ceramics before and after TiO2 coating was observed by SEM. The TiO2-coated porous ceramics were examined as honeycomb photocatalytic microreactors. The photocatalytic activity was evaluated
using the decomposition of methylene blue solution for radiation angles of 0° and 10° with respect to the pore axis. The highest
photocatalytic activity was obtained for the porous ceramic having the pore diameter of 0.1 mm, coated with titanyl(IV)acetylacetonate
and irradiated with a light angle of 0° with respect to the pore axis. 相似文献
15.
Lida T Nakamori R Yabuta R Yada S Takagi Y Mano N Ikegawa S Goto J Nambara T 《Lipids》2002,37(1):101-110
A facile and efficient synthesis of the carboxyl-linked glucosides of bile acids is described. Direct esterification of unprotected
bile acids with 2,3,4,6-tetra-O-benzyl-d-glucopyranose in pyridine in the presence of 2-chloro-1,3,5-trinitrobenzene as a coupling agent afforded a mixture of the
α- and β-anomers (ca. 1∶3) of the 1-O-acyl-d-glucoside benzyl ethers of bile acids, which was separated effectively on a C18 reversedphase chromatography column (isolated yields of α- and β-anomers are 4–9% and 12–19%, respectively). Subsequent hydrogenolysis
of the α- and β-acyl glucoside benzyl ethers on a 10% Pd−C catalyst in acetic acid/methanol/EtOAc (1∶2∶2, by vol) at 35°C
under atmospheric pressure gave the corresponding free esters in good yields (79–89%). Chemical specificities such as facile
hydrolysis and transesterification of the acyl glucosides in various solvents were also discussed. 相似文献
16.
A simple solid state technique for electrochemical micromachining of metal substrates using a metal ion conductor (Na-β″-Al2O3) was proposed. The fundamental solid electrochemical cell consists of a (anode) metal substrate (M = Ag, Cu, Zn, and Pb)/pyramidal Na-β″-Al2O3/Ag (cathode) system, where the contact diameter between M/Na-β″-Al2O3 was extremely small, on the order of a few micrometer. Under an applied electric field, the metal substrate was electrochemically oxidized to metal ions (Mn+) at the M/Na-β″-Al2O3 microcontact. These Mn+ ions migrated into the Na-β″-Al2O3. As a result of continuous electrolysis, the metal substrate was locally consumed at the microcontact, and thus solid state electrochemical micromachining was accomplished. As expected, the machining size or depth depended on the electrolysis conditions (current, operating time) and the apex configuration of pyramidal Na-β″-Al2O3. Moreover, the scanning of the Na-β″-Al2O3 pyramid during electrolysis produced a fine patterned metal substrate. In the present paper, solid state electrochemical micromachining was performed for several metal substrates, and its advantages and disadvantages vis-a-vis the conventional electrochemical micromachining method are discussed in detail. 相似文献
17.
Koji Matsui Kenji Tanaka Takanori Yamakawa Masato Uehara Naoya Enomoto Junichi Hojo 《Journal of the American Ceramic Society》2007,90(2):443-447
The shrinkage behavior of fine zirconia powders containing 2.9 and 7.8 mol% Y2 O3 was investigated to clarify the effect of Y2 O3 concentration on the initial sintering stage. The shrinkage of powder compact was measured under both conditions of constant rates of heating (CRH) and constant temperatures. CRH measurements revealed that when the Y2 O3 concentration of fine zirconia powder increased, the starting temperature of shrinkage shifted to a high temperature. Isothermal shrinkage measurements revealed that the increase in Y2 O3 concentration causes the shrinkage rate to decrease. The values of activation energy ( Q ) and frequency-factor term (β0 ) of diffusion at initial sintering were estimated by applying the sintering-rate equation to the isothermal shrinkage data. When the Y2 O3 concentration increases, both Q and β0 of diffusion increase. It is, therefore, concluded that the increase in Y2 O3 concentration of fine zirconia powder decreases the shrinkage rate because of increasing Q of diffusion at the initial stage of sintering. 相似文献
18.
针对微细金刚石磨粒很难从金属结合剂砂轮的胎体中出刃的问题,开发出一种新修锐方法一接触放电修锐、它采用一种旋转复合电极修整轮与砂轮接触磨削,在金属结合剂胎体与电极间产生微小的脉冲放电,逐渐去除砂轮的金属结合剂,使微细金刚石在砂轮工作表面出刃,达到精密修锐的目的。通过对金属结合剂#600金刚石砂轮进行修锐实验,研究其有效性、修锐条件和实际应用。实验表明,该修锐方法不仅不损伤微细金刚石磨粒出刃刃角,而且还可以消除磨粒周围的结合剂尾状物,产生较好的容屑空间。磨削光学玻璃(BK10)的试验结果显示它比机械修锐能够更好地提高磨削表面质量,Ra达到0.12μm。 相似文献
19.
Jiangyan Zhang Tielong Shen Junichi Kako Shozo Yoshida 《International Journal of Control, Automation and Systems》2009,7(4):659-667
In this paper, the speed control problem of internal combustion engines is investigated based on mean-value engine models.
The dynamics of internal combustion engines is a complicated nonlinear system, and usually, it is difficult to know the exact
values of the physical parameters. First, a Lyapunov-based design method is shown without requiring the full information of
the physical parameters. Then, to improve transient performance, the design method is extended to several cases under different
operation conditions. Numerical simulation results are presented for comparing the proposed design methods. Finally, experiments
are conducted on an engine test bench and the results demonstrate the validity of the proposed design methods.
Recommended by Editorial Board member Myotaeg Lim under the direction of Editor Hyun Seok Yang. The authors are grateful to
Kai Zheng for his assistance of the model identification experiments.
Jiangyan Zhang received the B.E. and M.E. degrees in Electrical Engineering, Yanshan University, China, in 2005 and 2008, respectively.
Now, she is a Ph.D. candidate with the Department of Engineering and Applied Sciences, Sophia University, Tokyo, Japan. Her
current research interests include nonlinear system control theory and applications to powertrain system control.
Tielong Shen received the Ph.D. degree in Mechanical Engineering from Sophia University, Tokyo, Japan, March, 1992. From April 1992, he
has been a faculty member of the Chair of Control Engineering in Department of Mechanical Engineering, Sophia University,
where he currently serves as professor of the Department of Engineering and Applied Science. His research interests include
control theory and application in mechanical systems, power systems, and automotive powertrain. Currently, he is an Associate
Editor for the IEEE Control System Society Conference Editorial Board, and is serving as Associate Editor of Journal of Control
Theory and Applications, and the Regional Editor Asia-Pacific for International Journal of Modeling, Identification and Control
etc.
Junichi Kako received the B.E. degree from Nagoya Institute of Technology, Nagoya, Japan. He joined Toyota Motor Corporation, Tokyo, Japan
in 1989. He worked on various aspects of automotive powertrain control. From 1989 to 1994, he took part in the team for the
development of Laboratory Automation (LA) system, Engineering Office Automation (EOD) system, and embedded system of powertrain
control. During 1995–2001, he focused on the engine control systems in Powertrain Management Engineering Division. In 2002,
he was with Future Project Division in which he was responsible for the R&D of model-based engine control system. Currently,
he is developing engine control systems in the Powertrain Management Engineering Division, Toyota Motor Corporation.
Shozo Yoshida received the M.S. degree in Engineering from Kyoto University, Kyoto, Japan. He joined Toyota Motor Corporation, Tokyo, Japan
in 2000. From 2000 to 2004, he was with Future Project Division and worked on physical combustion modeling for Model-based
Control Development. Since 2005, he has been with the Powertrain Management Engineering Division Toyota Motor Corporation,
and is a member of the R&D of Model-based Engine Calibration. 相似文献
20.
Cyclic variability is a factor adversely affecting engine performance. In this paper a cyclic moving average regulation approach to cylinder pressure at top dead center (TDC) is proposed, where the ignition time is adopted as the control input. The dynamics from ignition time to the moving average index is described by ARMA model. With this model, a one-step ahead prediction-based minimum variance controller (MVC) is developed for regulation. The performance of the proposed controller is illustrated by experiments with a commercial car engine and experimental results show that the controller has a reliable effect on index regulation when the engine works under different fuel injection strategies, load changing and throttle opening disturbance. 相似文献