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排序方式: 共有461条查询结果,搜索用时 546 毫秒
91.
K Maeda Y Nishiguchi N Onoda H Otani B Nakata S Yamada M Okuno M Sowa KH Chung 《Canadian Metallurgical Quarterly》1998,13(6):1147-1151
At least four genes involved in DNA mismatch repair (MMR), hMSH2, hMLH1, hPMS1 and hPMS2, have been cloned and characterized. These genes have been demonstrated to be altered in the germline of patients with hereditary non-polyposis colorectal cancer (HNPCC). HNPCC is an autosomal dominant disease characterized by a preponderance of proximal colon, young age of onset, increased multiplicity, and improved stage-specific survival. In this study, we examined the expression of hMSH2 protein in sporadic colorectal cancer (CRC). As a result, the frequency of right-sided CRC and multiple CRCs were significantly higher in the patients with hMSH2-negative CRC than in those with hMSH2-positive CRC. The rate of p53 positivity was significantly lower in the hMSH2-negative tumours than that in the hMSH2-positive tumours. The disease-free survival rate tended to be higher in the patients with hMSH2-negative CRC than in the patients with hMSH2-positive CRC. Our findings suggest that both the clinicopathological and biological features of hMSH2-negative sporadic CRC seemed to be similar to those of HNPCC. To clarify the mechanism of carcinogenesis in HNPCC and sporadic CRC, further investigations of genetic alterations caused by MMR genes will be needed. 相似文献
92.
Activities regarding tritium safety technology in the Tritium Process Laboratory (TPL) at Tokai Establishment of Japan Atomic Energy Research Institute are reviewed. Research and development of a new tritium removal system is being carried out by using a gas separation membrane which enable to make the ITER atmosphere detritiation system more compact and cost-effective. Techniques of gas flowing calorimetry and laser Raman spectroscopy are applied to develop new tritium accountancy methods. Studies of tritium-material interaction, such as plasma material interactions, radiochemical reaction of tritium in gas phase, radiolysis of tritiated water, and waste processing are being carried out under ITER/EDA and U.S.-Japan collaboration. Tritium release experiments for research of tritium behavior in confinements and environment and demonstration of safety related components are planned. 相似文献
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95.
A numerical method is presented for finding the surface current density on a two-dimensional smooth scatterer. This method is an improved version of a method which one of the authors presented as an adjoint method to the conventional mode-matching method (MMM) for finding the scattered field. After formulating the problem, we interpret the method being adjoint to the conventional mode-matching method and show that the method yields a sequence of approximate current densities converging to the true density in the mean squares sense. Next we propose the improved method and prove the fact that this method yields a sequence of approximate solutions which converges to the true density uniformly on the contour of the scatterer. We then state that the method is an adjoint one to the mode-matching method with a smoothing procedure (SP) which we proposed as a powerful numerical method for the scattered field. Numerical results of some sample calculation are attached to show the effectiveness of the new method. 相似文献
96.
Kazuo Tsutsui Ruifei Xiang Takashi Shiozawa Yasutoshi Okuno Masafumi Kubota Hiroshi Iwai 《Microelectronic Engineering》2008,85(2):315-319
The annealing conditions causing an irregular peak in sheet resistance of nickel silicides are investigated. It is found that the irregular rise in sheet resistance occurs at a critical temperature of 750-775 °C as a result of agglomeration related to phase transition from NiSi to NiSi2. Experiments on the effect of temperature, heating rate and annealing duration in rapid thermal annealing revealed that the high-resistance state produced by annealing at the critical temperature could not be changed by subsequent annealing at higher temperature, and that the high-resistance state required 30-40 s at the critical temperature to form. Pre-annealing at 600 °C was found to suppress the later formation of the high-resistance state. 相似文献
97.
In the mammalian brain, kynurenine aminotransferase (KAT) is pivotal to the synthesis of kynurenic acid, a preferential antagonist at the strychnine-insensitive NMDA-glycine site. As NMDA receptors are involved in autonomic function, we have examined the immunohistochemical localization of KAT in the medulla and spinal cord of the rat. KAT immunoreactivity (KAT-li) was found throughout these areas, in both glia and neurons. Unlike the mainly astrocytic localization in forebrain structures, KAT-li was predominantly neuronal, notably in areas important for blood pressure and heart rate regulation: ventral medulla, nucleus ambiguus, nucleus of the solitary tract and intramediolateral cell column of the spinal cord. The presence of KAT in these nuclei supports a neuromodulatory role for kynurenic acid in NMDA-mediated autonomic function. 相似文献
98.
Nagase R. Himeno A. Okuno M. Kato K. Yukimatsu K.-I. Kawachi M. 《Lightwave Technology, Journal of》1994,12(9):1631-1639
A compact, low-crosstalk 8×8 optical matrix switch module has been developed. A thermooptic switch chip and driving circuits with TTL interfaces are integrated on a 100-mm2 ceramic substrate. It achieved a low insertion loss of 10.0 dB, a low crosstalk level of -25.9 dB, and had excellent stability in practical operation. A photonic intermodule connector for electronic switching systems in the near future is also demonstrated through the use of these optical switch modules 相似文献
99.
H Abe N Okuno O Takeda Y Suminami H Kato K Nakamura 《Canadian Metallurgical Quarterly》1994,15(7):988-991
Squamous cell carcinoma (SCC) antigen was separated by two-dimensional electrophoresis combined with immunoblotting into four spots: spot 1 with pI 6.4 and 44.5 kDa, spot 2 with pI 6.3 and 44.5 kDa, spot 3 with pI 6.0 and 44.5 kDa, and spot 4 with pI 5.9 and 45 kDa. In cancer and noncancerous tissues, it was common that spot 1 was the largest spot. In noncancerous tissues, spot 3 was the smallest spot and spot 2 was stained as densely as spot 4. In cancer tissues, however, spot 4 was apparently smaller than spot 2 and 3. Also, spots 2 and 3 in cancer tissues were larger than those in noncancerous tissues. When SCC antigen was treated with alkaline phosphatase prior to isoelectric focusing (IEF), spot 4 disappeared from the immunoblotting pattern. When the SCC antigen was treated with alkaline phosphatase after IEF, spot 4 changed its molecular weight to the same weight as that of the other three spots. These results strongly suggest that spot 4 is phosphorylated SCC antigen. 相似文献
100.
K Inoue N Kiriike M Okuno Y Fujisaki M Kurioka S Iwasaki S Yamagami 《Canadian Metallurgical Quarterly》1998,44(12):1329-1336
BACKGROUND: Several lines of evidence indicate that abnormalities in brain dopamine and serotonin metabolism may play an important role in bulimia nervosa. However, the regional neurochemical mechanism of the binge eating is poorly understood. Our purpose was to elucidate brain neurochemical mechanisms of binge eating using a rat model. METHODS: The dopamine release and metabolism in the prefrontal cortex (PFC) and in the ventrolateral striatum (VLS) of rats were studied using microdialysis during enhanced rebound hyperphagia induced by space restriction (an animal model of binge eating). RESULTS: The rats showed rebound hyperphagic state when they were released from scheduled feeding (2 hours/day feeding for 7 days). The hyperphagia was further enhanced when they were put in a space-restricted cage where their mobility was restricted. Dopamine release and metabolism were increased both in the PFC and in the VLS during the enhanced rebound hyperphagia. CONCLUSIONS: These results tentatively suggest that increased dopamine release and metabolism in the PFC and in the VLS may be related to space restriction and to activation of motor function involved in feeding behavior, respectively. The enhanced rebound hyperphagia induced by space restriction may be useful as an animal model of binge eating. 相似文献