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排序方式: 共有556条查询结果,搜索用时 15 毫秒
551.
Carlos M. Campos Takashi Muramatsu Javaid Iqbal Ya-Jun Zhang Yoshinobu Onuma Hector M. Garcia-Garcia Michael Haude Pedro A. Lemos Boris Warnack Patrick W. Serruys 《International journal of molecular sciences》2013,14(12):24492-24500
The introduction of metallic drug-eluting stents has reduced the risk of restenosis and widened the indications of percutaneous coronary intervention in treatment of coronary artery disease. However, this medical device can induce hypersensitive reaction that interferes with the endothelialization and healing process resulting in late persistent or acquired malapposition of the permanent metallic implant. Delayed endotheliaization and malapposition may lead to late and very late stent thrombosis. Bioresorbable scaffolds (BRS) have been introduced to potentially overcome these limitations, as they provide temporary scaffolding and then disappear, liberating the treated vessel from its cage. Magnesium is an essential mineral needed for a variety of physiological functions in the human body and its bioresorbable alloy has the strength-to-weight ratio comparable with that of strong aluminum alloys and alloy steels. The aim of this review is to present the new developments in Magnesium BRS technology, to describe its clinical application and to discuss the future prospects of this innovative therapy. 相似文献
552.
Daichi Yazaki Tokuhisa Kawawaki Daisuke Hirayama Masanobu Kawachi Kosaku Kato Sota Oguchi Yuichi Yamaguchi Soichi Kikkawa Yoshiya Ueki Sakiat Hossain D. J. Osborn Fumihiko Ozaki Shunsuke Tanaka Jun Yoshinobu Gregory F. Metha Seiji Yamazoe Akihiko Kudo Akira Yamakata Yuichi Negishi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(34):2208287
For the realization of a next-generation energy society, further improvement in the activity of water-splitting photocatalysts is essential. Platinum (Pt) is predicted to be the most effective cocatalyst for hydrogen evolution from water. However, when the number of active sites is increased by decreasing the particle size, the Pt cocatalyst is easily oxidized and thereby loses its activity. In this study, a method to load ultrafine, monodisperse, metallic Pt nanoclusters (NCs) on graphitic carbon nitride is developed, which is a promising visible-light-driven photocatalyst. In this photocatalyst, a part of the surface of the Pt NCs is protected by sulfur atoms, preventing oxidation. Consequently, the hydrogen-evolution activity per loading weight of Pt cocatalyst is significantly improved, 53 times, compared with that of a Pt-cocatalyst loaded photocatalyst by the conventional method. The developed method is also effective to enhance the overall water-splitting activity of other advanced photocatalysts such as SrTiO3 and BaLa4Ti4O15. 相似文献
553.
Dr. Yusuke Kawamoto Wen Liu Ji Hye Yum Dr. Soyoung Park Prof. Dr. Hiroshi Sugiyama Dr. Yuki Takahashi Prof. Dr. Yoshinobu Takakura 《Chembiochem : a European journal of chemical biology》2022,23(4):e202100583
The present study focused on the design and synthesis of covalent DNA dendrons bearing multivalent cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODNs) that can stimulate the immune system through the activation of TLR9. These dendrons were synthesized using branching trebler phosphoramidite containing three identical protecting groups that enabled the simultaneous synthesis of multiple strands on a single molecule. Compared with linear ODNs, covalent DNA dendrons were found to be more resistant to nuclease degradation and were more efficiently taken up by macrophage-like RAW264.7 cells. Cellular uptake was suggested to be mediated by macrophage scavenger receptors. The covalent DNA dendrons composed of multivalent immunostimulatory branches enhanced the secretion of proinflammatory cytokines TNF-α and IL-6 from RAW264.7 cells, and 9-branched DNA dendrons showed the highest enhancement. Given their enhanced efficacy, we expect covalent DNA dendrons to be useful structures of oligonucleotide medicines. 相似文献
554.
Yushi Fujita Atsushi Sakuda Yuki Hasegawa Minako Deguchi Kota Motohashi Ding Jiong Hirofumi Tsukasaki Shigeo Mori Masahiro Tatsumisago Akitoshi Hayashi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(36):2302179
All-solid-state lithium–sulfur (Li/S) batteries are promising next-generation energy-storage devices owing to their high capacities and long cycle lives. The Li2S active material used in the positive electrode has a high theoretical capacity; consequently, nanocomposites composed of Li2S, solid electrolytes, and conductive carbon can be used to fabricate high-energy-density batteries. Moreover, the active material should be constructed with both micro- and nanoscale ion-conduction pathways to ensure high power. Herein, a Li2S–Li2O–LiI positive electrode is developed in which the active material is dispersed in an amorphous matrix. Li2S–Li2O–LiI exhibits high charge–discharge capacities and a high specific capacity of 998 mAh g−1 at a 2 C rate and 25 °C. X-ray photoelectron spectroscopy, X-ray diffractometry, and transmission electron microscopy observation suggest that Li2O–LiI provides nanoscale ion-conduction pathways during cycling that activate Li2S and deliver large capacities; it also exhibits an appropriate onset oxidation voltage for high capacity. Furthermore, a cell with a high areal capacity of 10.6 mAh cm–2 is demonstrated to successfully operate at 25 °C using a Li2S–Li2O–LiI positive electrode. This study represents a major step toward the commercialization of all-solid-state Li/S batteries. 相似文献
555.
Tomohiro Kawashima Taisuke Hirukawa Kanta Yoshikawa Yoshinobu Murakami Naohiro Hozumi 《Electrical Engineering in Japan》2023,216(1):e23418
The partial discharge (PD) waveform reflects the evolution process of electron avalanche in the discharge space. The authors expect to estimate the condition of the discharge space based on the PD waveform characteristics. The semi-conductive sheet was attached to the insulator to simulate the decrease in surface resistance due to deterioration. With the reduction of the surface resistivity, the shoulder appeared on the rising part of the PD waveform and the rise time of the PD waveform became longer. In addition, we simulated the change in the rise time using an equivalent circuit model. The displacement current was calculated from the surface potential distribution estimated by the diffusion equation, and the PD current was simulated by summing up all the current components. As a result, the shoulder was reproduced at the rising part of the PD waveform in the simulation as well. The surface resistance was estimated from the PD waveform by fitting with the experimental results. 相似文献
556.
The experiments of pre-ionized inert gas plasma MHD electrical power generation are conducted, and the performance and plasma behavior in the experimental generator are examined through time-dependent r-_ two-dimensional numerical simulation. In the experiment, an enthalpy extraction ratio of 4.01% has been obtained with a disk-shaped MHD generator with radio-frequency pre-ionization. In the numerical simulation, at an assumed inlet electron temperature around 5600 K (inlet ionization degree 0:10 × 10−4)_6600 K (1:36 × 10−4), the plasma structure is similar to the non-uniform structure observed in the experiment. An enthalpy extraction ratio around 2_5% matches well with that in the experiment. At a suitable inlet electron temperature of 7000 K (3:15 × 10−4)_8000 K (1:79 × 10−3), although non-uniform plasma structure still occurs, a high enthalpy extraction ratio over 10% is expected. 相似文献