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91.
92.
A 54-year-old woman who underwent a hysterectomy and radiation therapy for carcinoma of the uterine cervix developed mucosal de novo cancer of the rectum 12 years later. The rectal lesion was elevated, measuring 0.8 x 0.7 x 0.3 cm, and its surface was relatively smooth. Microscopically, this tumor consisted of a well-differentiated tubular adenocarcinoma which had invaded the depth of the mucosa. Late radiation injuries were observed around the tumor. We diagnosed this lesion as a radiation-induced mucosal de novo adenocarcinoma of the rectum on the basis of the criteria of Black and Ackerman (Clin Radiol 16:278, 1965). This case underscores the need for careful long-term follow-up studies of the large intestines of patients who underwent therapeutic irradiation for uterine cancer. 相似文献
93.
Ryo Watanabe Yasushi Sekine Masahiko Matsukata Eiichi Kikuchi 《Catalysis Letters》2009,131(1-2):54-58
We investigated novel LaMnOx perovskite-oxide (ABO3) catalysts for effective catalytic dehydrogenation of ethylbenzene to produce styrene monomer. Comparison with industrial Fe–K catalyst, our La0.8Ba0.2Mn0.6Fe0.4O3-δ catalyst showed higher activity. Results show that the A-site in perovskite-type oxides affected catalytic dehydrogenation activities and that the B-site affected stability of the activities. 相似文献
94.
Kazuyoshi Nishikawa 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2003,18(2-3):243
Prestressed & precast concrete segmental lining (P&PCSL) is used for shield tunnels. Its primary feature is that it integrates segments into one ring by introducing prestress in the tunnel circumferential and longitudinal directions. Introducing prestress enables the elimination of bolt joints and reduces the volume of reinforcement, thus reducing the manufacturing cost of precast concrete segments. It also enables quality improvement and labor saving in lining and provides greater adaptability for tunnels with large diameter, where deformation due to dead load is a problem. The P&PCSL has been implemented in three construction projects after undergoing various performance tests and workability verification tests. 相似文献
95.
Impact of Al in Cu alloy interconnects on electro and stress migration reliabilities 总被引:1,自引:0,他引:1
Kazuyoshi Maekawa Kenichi Mori Kazuhito Honda Koyu Asai Masayuki Kojima 《Microelectronic Engineering》2008,85(10):2137-2141
The reliability of Cu interconnects was successfully improved by applying a CuAl alloy seed. However, the effect of additive Al on the reliability is not fully understood. In order to reveal the reliability improvement mechanism, Cu films using CuAl alloy seed were investigated in detail. As stress induced voiding (SIV) as well as electromigration is caused by migration of vacancies and/or Cu atoms, the measured activation energy value of electromigration using CuAl indicates that the fast diffusion paths are Cu grain boundaries. The analysis using high lateral resolution scanning type secondary ion mass spectrometry (nano-SIMS) clarifies that additive Al in ECP-Cu film is mainly localized at grain boundaries. Furthermore, positron annihilation was used to probe vacancy-type defects in Cu films. The CuAl films before recrystallization contain larger and higher density vacancy-type defects. Whereas, the recrystallized CuAl films after annealing above 250 °C contain smaller and lower density defects. Furthermore, CuAl films with annealing above 350 °C contain less Al inside the grains. These results represent that Al atoms in Cu films with annealing above 350 °C are exhausted from inside grains to the grain boundaries, and the spewed Al atoms existing at Cu grain boundary effectively prevents the diffusion of Cu and/or vacancies. 相似文献
96.
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
97.
Shahira Said Aly Tsuyoshi Imai Mohamed Salah Hassouna Diem-Mai Kim Nguyen Takaya Higuchi Ariyo Kanno Koichi Yamamoto Rinji Akada Masahiko Sekine 《International Journal of Hydrogen Energy》2018,43(10):5300-5313
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum. 相似文献
98.
Shigekazu Yano Yukari Hori Tatsuro Kijima Hiroyuki Konno Wasana Suyotha Kazuyoshi Takagi Mamoru Wakayama 《Journal of Applied Glycoscience》2019,66(2):65
The cellulose binding domain (CBD) of cellulosome-integrating protein A from Clostridium thermocellum NBRC 103400 was genetically fused to FMN-dependent NADH-azoreductase (AZR) and glucose 1-dehydrogenase (GDH) from Bacillus subtilis. The fusion enzymes, AZR-CBD and CBD-GDH, were expressed in Escherichia coli Rosetta-gami B (DE3). The enzymes were purified from cell-free extracts, and the specific activity of AZR-CBD was 15.1 U/mg and that of CBD-GDH was 22.6 U/mg. AZR-CBD and CBD-GDH bound strongly to 0.5 % swollen cellulose at approximately 95 and 98 % of the initial protein amounts, respectively. After immobilization onto the swollen cellulose, AZR-CBD and CBD-GDH retained their catalytic activity. Both enzymes bound weakly to 0.5 % microcrystalline cellulose, but the addition of a high concentration of microcrystalline cellulose (10 %) improved the binding rate of both enzymes. A reactor for flow injection analysis was filled with microcrystalline cellulose-immobilized AZR-CBD and CBD-GDH. This flow injection analysis system was successfully applied for the determination of glucose, and a linear calibration curve was observed in the range of approximately 0.16–2.5 mM glucose, with a correlation coefficient, r, of 0.998. 相似文献
99.
Kazuyoshi Uruga Takeshi Tsukada Tsuyoshi Usami 《Journal of Nuclear Science and Technology》2020,57(4):433-443
ABSTRACTIn order to develop a glass production method that inhibits formation of the Mo-bearing secondary phase, the so-called yellow phase (YP), and also to clarify its formation behavior, vitrification tests using a small-scale liquid-fed ceramic melter (LFCM) were conducted. Chemically simulated PUREX liquid waste containing Na, Mo and other fission elements was fed into a molten glass pool in the melter together with several sizes of feed glass. When the glass beads with a diameter of around 2 mm were fed, some YP was contained in the vitrified glass products at 25 wt% waste loading. While, almost no YP was detected in the glass products when glass powder with a diameter of less than 63 μm was used. The microscopic analysis of the cold-cap samples revealed that powderization of the feed glass contributed to the facilitation of Na dissolution to the feed glass in the cold-cap. This quick intake of Na to the feed glass prevented the formation of liquid Na2MoO4 aggregation and provided homogeneous Mo dispersion in the cold-cap with forms of alkali earth and/or rare earth molybdates. The homogeneous dispersion of Mo resulted in the fast and complete dissolution of Mo in the glass melt. 相似文献
100.
PZT piezoelectric very thin films suitable for a microactuator have been deposited onto Invar alloy substrate using a high-temperature RF magnetron sputtering technique. PZT thin films must be deposited onto conductive substrate for a monomorph or a bimorph actuator. The chemical composition and the crystalline structure of these films were measured by ESCA and XRD, respectively. The chemical composition of PZT deposited stoichiometrically was almost the same as commercially-produced bulk PZT. Crystal planes (1 1 0) and (1 1 1) of PZT perovskite structure were observed in XRD analysis. When the substrate was heated to above 600 °C, SEM revealed only a very small number of pinholes on the surface. A thin (500 nm) film actuator has been characterized by measuring the piezoelectric property using a Laser Doppler Vibrograph. It was confirmed that the piezoelectric property has a linear relationship with the grain size, which also increased with the substrate temperature. The piezoelectric property of deposited PZT thin films showed a good agreement with a quoted value of bulk PZT, when the substrates were heated to 600 °C. 相似文献