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排序方式: 共有1402条查询结果,搜索用时 15 毫秒
81.
Noritaka Yonezawa Hideki Murakami Satoru Demura Satoshi Kato Shinji Miwa Katsuhito Yoshioka Kazuya Shinmura Noriaki Yokogawa Takaki Shimizu Norihiro Oku Ryo Kitagawa Makoto Handa Ryohei Annen Yuki Kurokawa Kazumi Fushimi Eishiro Mizukoshi Hiroyuki Tsuchiya 《International journal of molecular sciences》2021,22(4)
We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect. 相似文献
82.
Ryuichi Sugimoto Hideyuki Kaneko Junji Saito Nobuo Kawahara Shingo Matsuo Tomoaki Matsugi 《Polymer Bulletin》2014,71(6):1421-1431
This paper introduces the new synthetic methodology of polyolefin-based block and graft copolymers with polar segments [e.g., polystyrene and poly(meth)acrylates]. Various brominated polyolefins were prepared by bromination of polyolefins with N-bromosuccinimide. The resulting brominated polyolefins were able to initiate the controlled radical polymerization of polar monomers, such as methyl methacrylate, ethyl acrylate, t-butyl acrylate, styrene and 2-(dimethylamino)ethyl acrylate, using a CuBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine catalyst system, leading to a variety of polyolefin-based copolymers with a different content of the corresponding polar segment. Because of the accessible synthesis of polyolefin macroinitiators, this synthetic methodology is expected to result in the preparation of a wide range of polyolefin-based block and graft copolymers. 相似文献
83.
Fluorine-graphite intercalation compounds have been synthesized using high purity fluorine gas and high oxidation-state transition-metal fluorides, AgF3 and NiF3, at room temperature and at −78 °C. At room temperature, a mixture of stage 1 + 2 − 4 compounds with compositions, C4.2F to C14.6F were obtained. On the other hand, stage 2–4 compounds with compositions C5.6F to C14.2F were synthesized at −78 °C. The fluorinating ability of AgF3 and NiF3 has been shown more clearly at room temperature because a small amount of fluorine was intercalated/absorbed into graphite at −78 °C without catalysts. XPS spectra show that ionic, nearly ionic, semi-covalent and covalent fluorines coexist in the CxF samples, and that the covalency of CF bonding increases with decreasing stage number. 相似文献
84.
Nozomi Ishii Chie Sunaga Kanae Sano Dr. Chengcheng Huang Kenta Iino Dr. Yuji Matsuzaki Dr. Tadashi Suzuki Prof. Dr. Ichiro Matsuo 《Chembiochem : a European journal of chemical biology》2018,19(7):660-663
We developed a fluorescence‐quenching‐based assay system to determine the hydrolysis activity of endo‐β‐N‐acetylglucosaminidases (ENGases). The pentasaccharide derivative 1 was labeled with an N‐methylanthraniloyl group as a reporter dye at the non‐reducing end and with a 2,4‐dinitrophenyl group as a quencher molecule at the reducing end. This derivative is hydrolyzed by ENGase, resulting in an increase in fluorescence intensity. Thus, the fluorescence signal is directly proportional to the amount of the tetrasaccharide derivative, hence allowing ENGase activity to be evaluated easily and quantitatively. Using this system, we succeeded in measuring the hydrolysis activities of ENGases and thus the inhibitory activities of known inhibitors. We confirmed that this assay system is suitable for high‐throughput screening for potential inhibitors of human ENGase that might serve as therapeutic agents for the treatment of N‐glycanase 1 (NGLY1) deficiency. 相似文献
85.
Electron spin resonance of transparent alumina ceramics fabricated by spark plasma sintering 下载免费PDF全文
Transparent α‐alumina ceramics are fabricated using spark plasma sintering. Paramagnetic defects related to the optical properties of the ceramics have been investigated using electron spin resonance (ESR) analyses. An isotropic ESR signal at g = 2.003 (S = 1/2) with a linewidth of 0.5 mT is formed during sintering. The g = 2.003 signal intensity has a weak correlation with the absorbance in the visible region but does not correlate with the real in‐line transmission (RIT) at 650 nm. An ESR signal with a fine structure attributed to Fe3+ was detected in both the α‐Al2O3 starting powder and the sintered ceramic samples. The degree of c‐axis orientation of the grains has been determined using the Fe3+ signal intensity, which depends on the angle between the directions of the c‐axis and the applied magnetic field. The ESR analysis indicated that the c‐axis tends to be oriented in the direction of the sintering pressure. The degree of c‐axis orientation was found to correlate with the RIT in highly densified ceramics. 相似文献
86.
T. Akiya T. Shimazaki M. Oowa M. Matsuo Y. Yoshida 《International Journal of Thermophysics》1999,20(6):1753-1763
There are two promising candidates as alternative refrigerants for air-conditioners and heat pumps. The first is R407C, which is composed of HFC-32 (23 mass%), HFC-125 (25 mass%), and HFC-134a (52 mass%). The second is R410A, which is composed of HFC-32 (50 mass%) and HFC-125 (50 mass%). In this study, formation conditions of clathrate compounds between water and HFC alternative refrigerants such as HFC-32, HFC-125, HFC-134a, and their mixtures, R407C and R410A, were investigated. Phase diagrams of clathrates of these HFC alternative refrigerants and their mixtures were determined. From the phase diagrams, the critical decomposition temperature and the critical decomposition pressure were determined. The relationship between the critical decomposition points for the clathrates of HFC-32, HFC-125, HFC-134a, R410A, and R407C were studied. It is found that R407C and R410A form clathrate compounds with water under the evaporating temperature condition in the refrigeration cycle of air-conditioners and heat pumps. 相似文献
87.
Yuji Maruki Kohei Kawano Haruo Suemitsu Takami Matsuo 《International Journal of Control, Automation and Systems》2014,12(5):1040-1048
In this paper, we introduce a backstepping control design of a wheeled inverted pendulum. Based on a second-order motion equation of the body angle, an adaptive integral backstepping controller is designed to stabilize the body angle. It is shown that the σ-modification rule in the adaptive update law guarantees the boundedness of the errors in estimating the time-varying signal that is an output of a linear system with every bounded input signal. Then, the stabilizing controller for the wheel angle is constructed by a PD-type positive feedback. The derived controller requires the full-state measurements. In the output feedback case, the K filter or the observer backstepping is needed. However, the structure of the controller becomes complicated. We propose a non-model-based differentiator based on the adaptive update law. Since the non-model-based differentiator does not require any knowledge of the dynamic structure of the signal, we can use it as a velocity estimator for unknown nonlinear systems. Therefore, we replaced the velocity measurement with the estimates by the non-model-based differentiator. Finally, simulation results for the proposed controller are presented. 相似文献
88.
Yoshiaki Katada Akihiro Nishiguchi Kazuya Moriwaki Ryosuke Watakabe 《Artificial Life and Robotics》2016,21(3):295-301
One approach in swarm robotics is homogeneous system which is embedded with sensing, computing, mobile and communication components. In this study, a target detection problem, which is one of navigation problems, was employed. Once a robot detects a target, robots immediately communicate with a base station via intermediate relay robots due to the multi-hop transmission of wireless communication. Therefore, this control task is completed with connectivity of the network. In a target detection problem, we must improve the performance of exploration as well as connectivity of the network. This study investigates the performances of the two types of random walk algorithm in navigation while loosely ensuring connectivity of the robotic network based on our previous study. 相似文献
89.
A new dynamometer was developed for the measurement of specific movement power (SMP) exerted by mono- or multi-articular movements. To determine the reproducibility of SMP, two identical test protocols were carried out on separate days for six movement types on seven adult males. The movement types were arm pull (AP), leg rise (LR), knee extension (KE), elbow flexion (EF), hip extension (HE) and squat movement (SQ). Variations in peak power obtained in two tests ranged from 0.7% (AP) to 9.6% (SQ). Coefficients of the test-re-test correlation in peak power ranged from 0.805 (SQ) to 0.961 (AP) and standard errors ranged from 4 W (EF) to 14 W (SQ). SMP in upper extremities increased from 166 W (EF) to 307 W (AP) resulting from the increase in velocity. However, in the movements of lower extremities, SMP increased from 506 W (KE) to 1351 W (SQ) as a result of the increase in force. To evaluate the validity of the SMP, a pull movement in weightlifting was tested and related to the athletic performance on weightlifters. Positive linear correlation (r = 0.862, p<0.001) was observed between SMP and the total weight best records. It is concluded that this newly developed dynamometer has enough reproducibility and validity for evaluating the SMP, which is developed by various joint movement patterns related to the sport. The feasibility of applying this measuring protocol to the testing and training programmes for improving the daily living activities and athletic performances should now be assessed. 相似文献
90.
Keiji Nagatani Seiga Kiribayashi Yoshito Okada Kazuki Otake Kazuya Yoshida Satoshi Tadokoro Takeshi Nishimura Tomoaki Yoshida Eiji Koyanagi Mineo Fukushima Shinji Kawatsuma 《野外机器人技术杂志》2013,30(1):44-63
On March 11, 2011, a massive earthquake (magnitude 9.0) and accompanying tsunami hit the Tohoku region of eastern Japan. Since then, the Fukushima Daiichi Nuclear Power Plants have been facing a crisis due to the loss of all power that resulted from the meltdown accidents. Three buildings housing nuclear reactors were seriously damaged from hydrogen explosions, and, in one building, the nuclear reactions became out of control. It was too dangerous for humans to enter the buildings to inspect the damage because radioactive materials were also being released. In response to this crisis, it was decided that mobile rescue robots would be used to carry out surveillance missions. The mobile rescue robots needed could not be delivered to the Tokyo Electric Power Company (TEPCO) until various technical issues were resolved. Those issues involved hardware reliability, communication functions, and the ability of the robots' electronic components to withstand radiation. Additional sensors and functionality that would enable the robots to respond effectively to the crisis were also needed. Available robots were therefore retrofitted for the disaster reponse missions. First, the radiation tolerance of the electronic componenets was checked by means of gamma ray irradiation tests, which were conducted using the facilities of the Japan Atomic Energy Agency (JAEA). The commercial electronic devices used in the original robot systems operated long enough (more than 100 h at a 10% safety margin) in the assumed environment (100 mGy/h). Next, the usability of wireless communication in the target environment was assessed. Such tests were not possible in the target environment itself, so they were performed at the Hamaoka Daiichi Nuclear Power Plants, which are similar to the target environment. As previously predicted, the test results indicated that robust wireless communication would not be possible in the reactor buildings. It was therefore determined that a wired communication device would need to be installed. After TEPCO's official urgent mission proposal was received, the team mounted additional devices to facilitate the installation of a water gauge in the basement of the reactor buildings to determine flooding levels. While these preparations were taking place, prospective robot operators from TEPCO trained in a laboratory environment. Finally, one of the robots was delivered to the Fukushima Daiichi Nuclear Power Plants on June 20, 2011, where it performed a number of important missions inside the buildings. In this paper, the requirements for the exploration mission in the Fukushima Daiichi Nuclear Power Plants are presented, the implementation is discussed, and the results of the mission are reported. 相似文献