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排序方式: 共有1065条查询结果,搜索用时 15 毫秒
31.
Randeep Rakwal Ganesh Kumar Agrawal Junko Shibato Tetsuji Imanaka Satoshi Fukutani Shigeru Tamogami Satoru Endo Sarata Kumar Sahoo Yoshinori Masuo Shinzo Kimura 《International journal of molecular sciences》2009,10(3):1215-1225
We report molecular changes in leaves of rice plants (Oryza sativa L. - reference crop plant and grass model) exposed to ultra low-dose ionizing radiation, first using contaminated soil from the exclusion zone around Chernobyl reactor site. Results revealed induction of stress-related marker genes (Northern blot) and secondary metabolites (LC-MS/MS) in irradiated leaf segments over appropriate control. Second, employing the same in vitro model system, we replicated results of the first experiment using in-house fabricated sources of ultra low-dose gamma (γ) rays and selected marker genes by RT-PCR. Results suggest the usefulness of the rice model in studying ultra low-dose radiation response/s. 相似文献
32.
33.
The temperature‐dependent tip‐induced‐motion of a Ga adatom on a GaAs (110) surface is experimentally demonstrated using scanning tunneling microscopy (STM). The surface adsorption energy profile obtained by first‐principle electronic structure calculations reveals that the origin of the Ga motion observed at 78 K is attributable to the tip‐induced Ga adatom hopping between the most stable potential minima among the three local minima, whereas that observed at 4.2 K is attributable to the tip‐induced hopping and sliding motions through the next stable minima as well as the most stable minima. Furthermore, it is shown that a slight progressive modification of the adatom motion observed only at 4.2 K resulting from repeated STM line scans is consistent with the overall picture taking account of the heating of the adatom owing to the tip current. 相似文献
34.
Yasuyoshi Kaneko Shinya Matsushita Yasufumi Oikawa Shigeru Abe 《Electrical Engineering in Japan》2010,172(2):47-54
The equivalent circuit, the efficiency, and the important characteristics of moving pick‐up type contactless power transfer systems are described. If the primary series capacitor and the secondary parallel capacitors are chosen correctly and the winding resistances are ignored, the equivalent circuit of the transformer with these capacitors becomes the same as an ideal transformer at the resonant frequency. This simple approximation helps to understand the phenomena occurring with load changes. Because the circuit analysis becomes simple, the approximate value of the power transfer efficiency can be derived. This paper describes the determination of the capacitor values, the derivation of the equivalent circuit and the efficiency, and test results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(2): 47–54, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20970 相似文献
35.
36.
Kazuhiro Hirano Hideki Yamauchi Naoya Nakahara Kazuo Kinoshita Maki Yamaguchi Shigeru Takemori 《International journal of molecular sciences》2021,22(23)
We performed X-ray diffraction analyses on rat plantaris muscle to determine if there are strain-specific structural changes at the molecular level after eccentric contraction (ECC). ECC was elicited in situ by supramaximal electrical stimulation through the tibial nerve. One hour after a series of ECC sessions, the structural changes that remained in the sarcomere were evaluated using X-ray diffraction. Proteins involved in cell signaling pathways in the muscle were also examined. ECC elicited by 100, 75, and 50 Hz stimulation respectively developed peak tension of 1.34, 1.12 and 0.79 times the isometric maximal tetanus tension. The series of ECC sessions phosphorylated the forkhead box O proteins (FoxO) in a tension-time integral-dependent manner, as well as phosphorylated the mitogen-activated protein kinases (MAPK) and a protein in the mammalian target of rapamycin (mTOR) pathway in a maximal tension dependent manner. Compared to isometric contractions, ECC was more efficient in phosphorylating the signaling proteins. X-ray diffraction revealed that the myofilament lattice was preserved even after intense ECC stimulation at 100 Hz. Additionally, ECC < 75 Hz preserved the molecular alignment of myoproteins along the myofilaments, while 75-Hz stimulation induced a slight but significant decrease in the intensity of meridional troponin reflection at 1/38 nm−1, and of myosin reflection at 1/14.4 nm−1. These two reflections demonstrated no appreciable decrease with triple repetitions of the standard series of ECC sessions at 50 Hz, suggesting that the intensity decrease depended on the instantaneous maximal tension development rather than the total load of contraction, and was more likely linked with the phosphorylation of MAPK and mTOR signaling proteins. 相似文献
37.
Masaharu Kamei Sumiko Ohgaki Tamotsu Kanbe Isao Niiya Haruo Mizutani Isao Matsui-Yuasa Shuzo Otani Shigeru Morita 《Lipids》1995,30(6):533-539
We investigated the relationship between dietary highly hydrogenated soybean oil (HSO) and cholesterol transport in rats.
In the first study, to examine the effects of cholesterol transport of different concentrations of HSO in dietary oil, rats
were given one of the three diets containing 0, 25, or 50% HSO in dietary oil with cholesterol (5 g/kg diet) or a diet without
HSO and cholesterol for 22 d. Feeding the high concentration of HSO prevented the increase in plasma total cholesterol, hepatic
total lipids, and cholesterol and the decrease in high-density lipoprotein-cholesterol, which were caused by dietary cholesterol.
Moreover, HSO increased the fecal excretion, fecal lipids, and steroids in a dose-dependent manner. In the second study, to
examine the effects on cholesterol transport of redistribution of stearic acid in the triacylglycerol species contained in
HSO, rats were given one of the six diets containing HSO (distearoylmonoacylglycerol and tristearoylglycerol)-rich, monostearoylglycerol-rich,
or palmitic acid-rich oil with/without cholesterol (5 g/kg diet), for 30 d. Whereas the accumulation of cholesterol in the
body was reduced, cholesterol excretion was enhanced effectively in rats given the HSO-rich diet compared with rats given
the monostearoylglycerol-rich diet. These results suggested that not only the high concentration of stearic acid but also
its uneven distribution in HSO-triacylglycerol contributed to the reduction in intestinal cholesterol absorption in rats. 相似文献
38.
Yuichi Ichihashi Yo-hei Kamizaki Naoya Terai Keita Taniya Shigeru Tsuruya Satoru Nishiyama 《Catalysis Letters》2010,134(3-4):324-329
The gas-phase catalytic oxidation of benzene over copper supported on HZSM-5 added with titanium (Cu/Ti/HZSM-5) was carried out by using molecular oxygen as an oxidant. Phenol was effectively produced by the titanium addition to Cu/HZSM-5. The titanium addition to Cu/HZSM-5 induces the easy reduction of Cu2+ species to Cu+ species in the catalysts, and the produced Cu+ species seems to produce the phenol effectively. 相似文献
39.
Shigeru Sugiyama Yuhki Kato Takahiro Wada Shirou Ogawa Keizo Nakagawa Ken-Ichiro Sotowa 《Topics in Catalysis》2010,53(7-10):550-554
MCM-41 and FSM-16 were both prepared using no hydrothermal conditions, and nickel was doped into these catalysts (Ni-MCM-41 and Ni-FSM-16) using a template ion exchange method. FSM-16 and Ni-FSM-16 had greater catalytic activity for the conversion of ethanol than MCM-41 and Ni-MCM-41, indicating that FSM-16 has potential as a catalyst for the conversion of ethanol to propylene. 相似文献
40.
Tomoharu Suzuki Shigeru Oshio Mari Iwata Hisayo Saburi Takashi Odagiri Tadashi Udagawa Isamu Sugawara Masakazu Umezawa Ken Takeda 《Particle and fibre toxicology》2010,7(1):1-8