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排序方式: 共有488条查询结果,搜索用时 15 毫秒
481.
Satoshi Abo Naoyuki MasudaFujio Wakaya Shinobu OnodaTakahiro Makino Toshio HiraoTakeshi Ohshima Toshiaki IwamatsuHidekazu Oda Mikio Takai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(20):2360-2363
Soft errors induced by proton, helium and oxygen ion irradiations were measured as a function of distance between a body electrode under partial trench isolation and a metal pad connected to a tungsten via for the first metal layer of a silicon-on-insulator (SOI) static random access memory. Abnormal drain charges induced by ion irradiations with various distances in the SOI metal oxide semiconductor field effect transistor were simulated to be compared with the experimental results. The soft errors were found to depend on the distance between the body electrode and the metal pad in the case of the abnormal drain charge, which is induced by incident ions, lower than the critical charge of the SRAM cells. The soft errors did not depend on the distance for the abnormal drain charges higher than the critical charge. 相似文献
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483.
Xia Zhang Rikiya Taoka Dage Liu Yuki Matsuoka Yoichiro Tohi Yoshiyuki Kakehi Mikio Sugimoto 《International journal of molecular sciences》2021,22(8)
RRM1—an important DNA replication/repair enzyme—is the primary molecular gemcitabine (GEM) target. High RRM1-expression associates with gemcitabine-resistance in various cancers and RRM1 inhibition may provide novel cancer treatment approaches. Our study elucidates how RRM1 inhibition affects cancer cell proliferation and influences gemcitabine-resistant bladder cancer cells. Of nine bladder cancer cell lines investigated, two RRM1 highly expressed cells, 253J and RT112, were selected for further experimentation. An RRM1-targeting shRNA was cloned into adenoviral vector, Ad-shRRM1. Gene and protein expression were investigated using real-time PCR and western blotting. Cell proliferation rate and chemotherapeutic sensitivity to GEM were assessed by MTT assay. A human tumor xenograft model was prepared by implanting RRM1 highly expressed tumors, derived from RT112 cells, in nude mice. Infection with Ad-shRRM1 effectively downregulated RRM1 expression, significantly inhibiting cell growth in both RRM1 highly expressed tumor cells. In vivo, Ad-shRRM1 treatment had pronounced antitumor effects against RRM1 highly expressed tumor xenografts (p < 0.05). Moreover, combination of Ad-shRRM1 and GEM inhibited cell proliferation in both cell lines significantly more than either treatment individually. Cancer gene therapy using anti-RRM1 shRNA has pronounced antitumor effects against RRM1 highly expressed tumors, and RRM1 inhibition specifically increases bladder cancer cell GEM-sensitivity. Ad-shRRM1/GEM combination therapy may offer new treatment options for patients with GEM-resistant bladder tumors. 相似文献
484.
Ephantus Nguma Yuki Tominaga Shinji Yamashita Yurika Otoki Ayaka Yamamoto Kiyotaka Nakagawa Teruo Miyazawa Mikio Kinoshita 《Lipids》2021,56(2):167-180
Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.3 mol% PlsEtn in EtnGpl) and porcine liver (7.2 mol% PlsEtn in EtnGpl) in 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in vivo, and elucidated the possible underlying mechanisms behind it. Dietary EtnGpl-suppressed DMH-induced aberrant crypt with one foci (AC1) and total ACF formation (P < 0.05). ACF suppression by dietary ascidian muscle EtnGpl was higher compared with dietary porcine liver EtnGpl. Additionally, dietary EtnGpl decreased DMH-induced oxidative damage, overproduction of TNF-α, and expression of apoptosis-related proteins in the colon mucosa. The effect of dietary ascidian muscle EtnGpl showed superiority compared with dietary porcine liver EtnGpl. Our results demonstrate the mechanisms by which dietary PlsEtn suppress ACF formation and apoptosis. Dietary PlsEtn attained this suppression by reducing colon inflammation and oxidative stress hence a reduction in DMH-induced intestinal impairment. These findings provide new insights about the functional role of dietary PlsEtn during colon carcinogenesis. 相似文献
485.
Europiumis one of the most important rare earth(RE) element .It is widely used as a component ofcathode ray tubes , with screen coated with red phos-phor ,as phosphorescent pigments ,andinlaser optics .It can also be used as neutron-absorbing material .In… 相似文献
486.
ABSTRACT The fine crystals of ammonium tungstophosphate (AWP) exchanger were immobilized in the biopolymer consisting of calcium alginate (CaALG) gels. The uptake rate of Cs+ for the AWP-CaALG composite was fairly fast and the uptake percentage of Cs? was above 90 % within 30 min even in the presence of 5 M HNO3 In a wide HNO3concentration region of 0.1 - 5 M, the distribution coefficient of Cs? for the composite was about 104 cm3/g, while those for other nuclides, Na+, Sr2+, Co2+, Eu3+ and Am3+, were less than 10 cm3/g. The uptake of Cs+ followed a Langmuir-type adsorption equation, and the maximum uptake capacity of Cs+ increased with the content of AWP immobilized in the composite. The trace amounts of 137Cs in the presence of 5 M NaNO3-l M HNO3 were selectively adsorbed on the composite column. The AWP-CaALG composite proved to be effective for the selective removal of radioactive cesium from waste solutions containing HNO3 and NaNO3 相似文献
487.
488.
In the context of evolutionary quantum computing in the literal meaning, a quantum crossover operation has not been introduced so far. Here, we introduce a novel quantum genetic algorithm that has a quantum crossover procedure performing crossovers among all chromosomes in parallel for each generation. A complexity analysis shows that a quadratic speedup is achieved over its classical counterpart in the dominant factor of the run time to handle each generation. 相似文献