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排序方式: 共有1625条查询结果,搜索用时 31 毫秒
1.
Hiromasa Tanno Emi Kanno Suzuna Sato Yu Asao Mizuki Shimono Shiho Kurosaka Yukari Oikawa Shinyo Ishi Miki Shoji Ko Sato Jun Kasamatsu Tomomitsu Miyasaka Hideki Yamamoto Keiko Ishii Yoshimichi Imai Masahiro Tachi Kazuyoshi Kawakami 《International journal of molecular sciences》2021,22(8)
Chronic infections are considered one of the most severe problems in skin wounds, and bacteria are present in over 90% of chronic wounds. Pseudomonas aeruginosa is frequently isolated from chronic wounds and is thought to be a cause of delayed wound healing. Invariant natural killer T (iNKT) cells, unique lymphocytes with a potent regulatory ability in various inflammatory responses, accelerate the wound healing process. In the present study, we investigated the contribution of iNKT cells in the host defense against P. aeruginosa inoculation at the wound sites. We analyzed the re-epithelialization, bacterial load, accumulation of leukocytes, and production of cytokines and antimicrobial peptides. In iNKT cell–deficient (Jα18KO) mice, re-epithelialization was significantly decreased, and the number of live colonies was significantly increased, when compared with those in wild-type (WT) mice on day 7. IL-17A, and IL-22 production was significantly lower in Jα18KO mice than in WT mice on day 5. Furthermore, the administration of α-galactosylceramide (α-GalCer), a specific activator of iNKT cells, led to enhanced host protection, as shown by reduced bacterial load, and to increased production of IL-22, IL-23, and S100A9 compared that of with WT mice. These results suggest that iNKT cells promote P. aeruginosa clearance during skin wound healing. 相似文献
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3.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
4.
Hiroaki Matsumori Toshihisa Shimizu Koushi Takano Hitoshi Ishii 《Electrical Engineering in Japan》2015,190(2):57-71
In recent years, remarkable advancement of new power semiconductor devices, such as SiC and GaN, enables the increase of switching frequency of power converters, and hence the volume of passive components, such as ac filters and transformers, can be reduced. However, temperature rise caused by the inductor loss is increasing, and hence iron loss evaluation of the inductor is one of the most important issues to realize high power density converters. Conventionally, an improved generalized Steinmetz equation (iGSE) has proposed in order to calculate the iron loss under a pulse voltage magnetizing condition. However, accurate iron loss calculation of the ac filter inductor used in a PWM inverter cannot be realized. The authors have proposed two methods of iron loss evaluation of ac filter inductors. The first one is a loss map method which can calculate the iron loss without using a real PWM inverter. Another one is an ILA (Inductor Loss Analyzer) which can measure the iron loss in every switching period in a real PWM inverter. In this paper, comparisons of the iron loss between the ILA and the loss map method on both the single‐phase and three‐phase inverters are studied. It is found that iron loss of the ac filter inductor in the three‐phase PWM inverter which is calculated by the loss map method cause a large error on a specific condition. In order to prevent the calculation error, the authors proposed a revised loss map method and proved the effectiveness of the method. 相似文献
5.
Finn Edler von Eyben Glenn Bauman Rie von Eyben Kambiz Rahbar Cigdem Soydal Alexander R. Haug Irene Virgolini Harshad Kulkarni Richard Baum Giovanni Paganelli 《International journal of molecular sciences》2020,21(23)
The aim of the review was to evaluate patient and treatment characteristics for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with PSMA radioligand therapy (PRLT) associated with above-average outcome. The systematic review and meta-analysis followed recommendations by the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA). We searched for publications in PubMed, Embase, and ClinicalTrials.gov up to 31 September 2020. Thirty-six publications and four duplicates reported 2346 patients. Nearly two-thirds of the patients had bone metastases. Median overall survival (OS) was 16 months. Asymptomatic patients and patients with only lymph node metastases lived longer than symptomatic patients and patients with more extensive metastases. Patients treated with an intensified schedule of 177Lu PRLT lived longer than those treated with a conventional schedule. Half of the patients obtained a PSA decline ≥ 50% and these patients lived longer than those with less PSA decline. Approximately 10% of the patients developed hematologic toxicity with anemia grade 3 as the most severe adverse effect. Characteristics for patients, cancer, restaging, and PRLT predict above average overall survival following treatment with PRLT. 相似文献
6.
Mikihisa Saito Masaru Ishii Atsushi Ohnishi Fumiyuki Fujii Michihiro Matsui Daisuke Natsuno 《Electrical Engineering in Japan》2015,190(1):37-44
In recent years, frequent damage to wind turbines by winter lightning has been reported in the region along the Sea of Japan. It is a serious finding that lightning hits concentrate on wind turbines in this region. The authors investigated the increase rate of the frequency of lightning hits on wind turbines due to wind turbine construction by using LLS (lightning location system) data. As a result, an experimental formula to estimate the increase rate of the frequency of lightning hits on wind turbines as a function of parameters related to the construction conditions, namely the height of wind turbines, the height above sea level, and the latitude, is proposed. 相似文献
7.
Toshihisa Shimizu Keisuke Kakazu Koushi Takano Hitoshi Ishii 《Electrical Engineering in Japan》2015,192(4):51-63
Because of the improved performance of power devices, the volume of the ac filter inductors used in high‐frequency PWM inverters has been reduced. However, the temperature rise in the filter inductor due to this miniaturization has become more pronounced. Therefore, we have proposed an iron loss calculation method for the ac filter inductor. However, the accuracy of the value calculated via the loss map method cannot be verified, because the iron loss arising during each switching period cannot be measured with conventional power measuring instruments. In order to resolve this problem, we developed an inductor loss analyzer (ILA), which allows precise measurement of the iron loss in the inductor during each switching period. The accuracy of the calculation of iron loss in the filter inductor by the loss map method was verified with the ILA. We found that the value calculated by the loss map method differed slightly from the value measured with the ILA. However, these differences can be reduced if we take into account the accurate flux density calculation and the effect of the duty ratio of PWM pulses on the loss. Finally, we verified that the loss map method can provide accurate iron loss calculations. 相似文献
8.
Evaluation of standing‐sitting support system with passive rotational seat mechanism in standing motion 下载免费PDF全文
Hiroyuki Sogo Tomohiro Henmi Shinichiro Shobako Kohei Ishii Suguru Eto Yuta Ogata 《Electrical Engineering in Japan》2018,205(2):16-25
Since a decrease in muscle mass of elderly people, the physical burden of them in standing‐sitting motion of a seat are increasing than young people. For this problem, several standing‐sitting support systems have been developed, and evaluations of these systems focusing on a reduction of physical load have been discussed. However, these evaluations are of support systems with an active actuators or of support systems when they use a handrail and a standing aid. Thus, an evaluation of a support system with only passive actuators has not been reported. In this paper, in standing motion with using a standing‐sitting support system with passive rotational seat mechanism which our group proposes, we objectively evaluate an effectiveness of the passive rotational seat mechanism by statistical analysis. 相似文献
9.
Masanori Suzuki Norimasa Umesaki Yoshiki Ishii 《Journal of the American Ceramic Society》2022,105(1):700-711
Dicalcium silicate, which is found in steelmaking slag for dephosphorization, exists as the hexagonal α phase at high temperatures. The α-dicalcium silicate forms a solid solution with tricalcium phosphate in the entire composition range, although the reason for high solubility of phosphorus remains unclear in view of the crystal structure. It has previously been reported that the crystal structure of α-dicalcium silicate consists of a symmetric arrangement of Ca2+ ions and SiO44− tetrahedra, although other polymorphs exhibit asymmetric arrangements. However, because the occupation probability of each atomic site in the α polymorph is not limited to unity, it has not been qualified how these ions are exactly arranged. In this study, the ionic distribution in the α polymorph of dicalcium silicate was evaluated by first-principles calculation based on density functional theory (DFT), as well as by molecular dynamics (MD) simulation with a polarizable ion model optimized by DFT calculation. The results indicated that the completely symmetric ionic arrangement, as reported for the α phase, is the most unstable. Electronic-state calculation and MD simulation indicated that a highly disordered ionic arrangement spontaneously forms in the α-phase crystal for structure relaxation when held at high temperatures, or when phosphorus is incorporated. 相似文献
10.
Kento Ishii Chika Matsunaga Kiyoshi Kobayashi Adam J. Stevenson Caroline Tardivat Tetsuo Uchikoshi 《Journal of the European Ceramic Society》2021,41(4):2709-2715
The Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF)-based multi-layered oxygen separation membrane was fabricated by the sequential electrophoretic deposition (EPD) process. A thin porous/dense bi-layer of BSCF was formed on a thick porous support of BSCF. The porous support prepared by a sacrificial template method using BSCF powder mixed with wheat starch (30 wt%) as a pore-forming agent, followed by uniaxial pressing and low-temperature sintering, was directly used as an EPD electrode. A thin BSCF layer was first formed on the porous support, and then a thin BSCF + PMMA (polymethyl methacrylate) layer was sequentially formed on the thin BSCF layer using a bimodal suspension of BSCF and PMMA. A 30-μm thin porous/dense bi-layer of BSCF of which the total thickness was obtained by optimizing the processes of EPD and subsequent co-sintering. The oxygen separation performance of 3.7 ml (STP) min?1 cm?2 at 860 °C was achieved for the BSCF-based multi-layered oxygen separation membrane. 相似文献