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排序方式: 共有240条查询结果,搜索用时 15 毫秒
1.
E Kumazawa K Hirotani SC Burford K Kawagoe T Miwa I Mitsui A Ejima 《Canadian Metallurgical Quarterly》1997,45(9):1470-1474
Novel benzophenone derivatives were synthesized and screened for cytotoxic and antitumor activity. Friedel-Crafts condensation was employed to construct the benzophenone skeleton. Among the compounds synthesized, morpholino and thiomorpholino benzophenones 3a-d exhibited potent cytotoxic activity against P388 murine leukemia and PC-6 human lung carcinoma cells in vitro, and compounds 3a, 3c, and 3j, when administered intraperitoneally, showed significant antitumor activity against the malignant ascites caused by intraperitoneal inoculation of P388 cells in mice. 相似文献
2.
S Ikezaki A Nishikawa F Furukawa T Imazawa M Mitsui T Enami M Takahashi 《Canadian Metallurgical Quarterly》1995,(113):44-50
A 13-week subchronic toxicity study of josamycin was performed in male and female F344 rats to determine the maximum tolerable dose (MTD) for subsequent investigation of the carcinogenicity. As animals refused to take diet containing 5.0% josamycin in our preliminary study, dose levels in the present study were determined as 0, 0.16, 0.32, 0.63, 125 and 2.5% in diet. Rats were randomly allocated to 6 groups, each consisting of 10 males and 10 females. No animal died during the administration period and no group showed significant changes in body weight gain. Definite toxicity of josamycin was not noted in hematological and serum biochemical examinations. Histopathological examinations revealed no particular findings related to josamycin administration except cecal enlargement in the 1.25 and 2.5% groups. based on the results of the present study, it was concluded that the MTD of josamycin in 2.5% in diet, because the dietary dose level of 2.5% proved to exert no significant toxicological signs. 相似文献
3.
Electrical insulation of superconducting magnets needs to endure a variety of voltages with a large range of shapes, magnitudes and duration under normal operation, during coil quenching, and at withstand voltage tests. The author reviews the current state of electrical insulation technology for superconducting magnets in Japan. He maintains that Japan will continue to aggressively pursue the research, development and application of superconducting magnets. In accordance with this, the main technical subjects to be solved in the insulation of the superconducting magnets in the near future will be: (1) the development of insulation that has high electrical, mechanical and radiation-resistant properties at the cryogenic condition; and (2) investigation into the long-range effects of insulation on the stability of superconducting magnets 相似文献
4.
5.
Y Nakazawa K Mitsui Y Hirai K Takahashi T Ishikawa 《Canadian Metallurgical Quarterly》1994,35(4):197-205
The purpose of this experiment was to investigate histo-pathologically the pulpal reaction to a glass-ionomer/resin (Geristore) restoration system in human teeth. Black's class I cavities were prepared in 22 human teeth; these were divided into 2 groups, one with the Geristore after cavity was cleaned with 10% NaOCl solution and 3% H2O2 solution (Group G) and the other with the Geristore after the cavity was applied with Mirage-Bond (Group MG). The treated teeth were observed clinically over 90 days after operation. They were then extracted for histological examination. No unpleasant symptoms were noted. A few pathological changes were observed. No histo-pathological score differences were observed between groups G and MG. The average evaluation score of pathological results in both groups G and MG were excellent. Microorganisms observed in the cavity dentin of the group G was fewer than in group MG. In some cases, microorganisms were observed along the dentin walls. In conclusion, the pulpal injury due to this Geristore restoration system was slight, and the system was considered to be safe for the pulp and clinically useful. 相似文献
6.
S. Mitsui M. Shionoya K. Gohke F. Watanabe S. Imaizumi Y. Senda 《Journal of Catalysis》1975,40(3):372-378
In order to investigate the steric effect of the substituents to determine the product distribution, disubstituted cyclohexenes were hydrogenated over several transition metal catalysts. Some cyclohexenes which have two large substituents at the vicinal carbon atoms, at least one of which is trigonal, were not hydrogenated over Raney Ni at all but were hydrogenated over Pt catalyst under our experimental conditions. Presumably, the stereoselectivity depends on the competitive operation of the torsional angle strain and the catalyst hindrance with substituents. In the hydrogenation over Pd catalyst, thermodynamically more stable products were dominant at the standard condition but at high substrate to catalyst ratio the less stable products were slightly preferred. No appreciable stereoselectivity was observed in the hydrogenation of 1,4-disubstituted cyclohexenes. 相似文献
7.
Yoshiyuki Kibe Yusuke Okada Kimiyuki Mitsui 《International Journal of Machine Tools and Manufacture》2007,47(11):1728-1737
In the shearing process, clearance has a significant effect on machining accuracy. However, the relationship between uneven clearance caused by misalignment of tool position and machining accuracy remains unclear. This is attributed to the fact that, previously, the effect was small because the thickness of the workpiece was not so thin, and a method for precisely measuring and adjusting the tool position had not been established. Therefore, in the present study, a new method of adjusting the initial tool position is developed. In addition, punching experiments are conducted under the condition that the initial tool position is adjusted to an accuracy of 2 μm or better, and the effects of clearance on machining accuracy, shape of cross-section, and diameter of hole, are investigated in three types of materials. From these results, the importance of adjusting the initial tool position is clarified. 相似文献
8.
基于微放电加工元件轮廓测量的探针制造 总被引:1,自引:0,他引:1
KAWADAMasayoshi MITSUIKimiyuki 《纳米技术与精密工程》2004,2(2):124-131
为了推动微加工和微机械技术的进步,微型零件轮廓和尺度测量方法的发展非常重要.可行方法之一就是使用带微探头的小型三维轮廓测量仪.这种仪器的探头必须针对某个零件的测量,按照最佳外形制造.微放电加工有着极小加工力,可用于各种探头的制造,本研究中用它进行探头加工.用这种方法制造了多种探头,将其装在基于扫瞄隧道显微技术(STM)的小型三维轮廓测量仪上.所制造的探头已被成功地用于各种微元件测量,结果表明此方法可行. 相似文献
9.