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排序方式: 共有571条查询结果,搜索用时 15 毫秒
91.
基于领域本体实现Web文本挖掘研究 总被引:1,自引:0,他引:1
92.
Jun-guo Yang Hai-ning Yu Shi-li Sun Lan-cui Zhang Guo-qing He Undurti N. Das Hui Ruan Sheng-rong Shen 《Journal of Zhejiang University. Science. B》2009,10(6):411-421
Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:l was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane,decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG. 相似文献
93.
He GQ Xiong HP Chen QH Ruan H Wang ZY Traoré L 《Journal of Zhejiang University. Science. B》2005,6(10):999-1004
Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations
of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at
50°C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids
(7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid
in hops.
Project (No. Y304203) supported by the Natural Science Foundation of Zhejiang Province, China 相似文献
94.
Objective: To observe the effects of fructose-1,6-diphosphate (FDP) on serum levels of cardiac troponin 1 (cTnl) and creatine kinase-MB (CK-MB), as well as the concentration of calcium in cardiomyocytes (Myo[Ca2 ]) and activity of sarcoplosnic Ca2 -ATPase (SRCa2 -ATPase) in Adriamycin (ADR)-treated rats. Methods: Rats were intraperitoneally injected with ADR (2.5 mg/kg every other day for 6 times) and then with different dosages of FDP (every other day for twenty-one times). Bi-antibodies sandwich Enzyme linked immune absorption assay (ELISA) was performed to detect serum level of cTnl. CK-MB was detected by monoclonal antibody, Myo[Ca2 ] was detected by fluorescent spectrophotometry and the activity of SRCa2 -ATPase was detected by inorganic phosphate method. Results: FDP (300, 600, 1200 mg/kg) significantly reduced the serum levels of cTnl and CK-MB, while at the same time decreased calcium concentration and increased SRCa2 -ATPase activity in cardiomyocytes of ADR-treated rats (P<0.01). Conclusions: FDP might alleviate the cardiotoxic effects induced by ADR through decreasing calcium level as well as increasing SRCa2 -ATPase activity in cardiomyocytes. 相似文献
95.
文章结合天津高职院校图书馆基于"馆藏揭示+开放获取"的专业性特色资源数据库建设实践,就如何分析、梳理、提炼、整合、存储基于学校专业建设的馆藏信息资源以及如何挖掘、整合和利用具有专业特色的开放获取文献信息资源进行了探讨,旨在探索一条适合高职院校的专业性特色资源建设之路。 相似文献
96.
EPSS是为了提高工作绩效利用计算机技术开发的一种电子绩效支持系统,这种系统具有信息集成性、工作情境性、学习自主性、知识共享性等特点。职工利用它既可以实现在工作中学习,又可以实现在学习中工作的职业教育功能。在EPSS逐渐成为促进职业技能发展,提高企业组织或个人绩效的干预措施之后,EPSS的开发成为实现职业教育功能和绩效支持的关键。乔尼(Nguyen)和沃尔(Woll)创建了一种EPSS开发模型,该模型从绩效角度和学习角度提出开发EPSS要经过绩效分析、EPSS分析、EPSS设计、EPSS开发、EPSS的实施与评价等几个阶段。乔尼和沃尔创建的EPSS开发模型将职工培训、工作绩效以及技术支持有效地融合于整个开发过程中,对设计、开发EPSS的实践者提供了一个简洁、便于操作的参考模型。 相似文献
97.
艺苑奇葩——莆仙戏曲的发展与创新 总被引:1,自引:0,他引:1
阮俊宇 《南昌教育学院学报》2012,(11):24-25
近年来,随着我国对外文化交流的增多,外来文艺形式大量涌入,当代青少年对传统地方戏曲已渐渐失去往日的热情,知音日渐减少。针对这种现象,立足于莆仙戏的剧本、唱腔音乐、舞台表演等方面,对莆仙戏音乐的继承、发展与创新提出看法。 相似文献
98.
This paper proposes a novel ranking approach, cost-sensitive ordinal classification via regression (COCR), which respects the discrete nature of ordinal ranks in real-world data sets. In particular, COCR applies a theoretically sound method for reducing an ordinal classification to binary and solves the binary classification sub-tasks with point-wise regression. Furthermore, COCR allows us to specify mis-ranking costs to further improve the ranking performance; this ability is exploited by deriving a corresponding cost for a popular ranking criterion, expected reciprocal rank (ERR). The resulting ERR-tuned COCR boosts the benefits of the efficiency of using point-wise regression and the accuracy of top-rank prediction from the ERR criterion. Evaluations on four large-scale benchmark data sets, i.e., "Yahoo! Learning to Rank Challenge" and "Microsoft Learning to Rank,” verify the significant superiority of COCR over commonly used regression approaches. 相似文献
99.
The evaluation of the seismic stability of an expanded municipal solid waste (MSW) landfill is very important in seismic prone zones. In this paper, the pseudo-dynamic method was used to calculate the average safety factor for the expanded landfill with a trapezoidal berm based on under-berm failure conditions. Furthermore, the effects of the variation of parameters such as the amplification factor, seismic coefficient, height of berm, angle of back slope of berm, and depth of waste mass at the back slope on the seismic stability of the landfill were studied. The results indicated that the influences of the vertical seismic coefficient, height of berm, and angle of the back slope of the berm on the seismic stability of the landfill are weakened as the amplification factor increases, but the influence of the horizontal seismic coefficient on the seismic stability of the landfill is strengthened. On the other hand, a certain ratio of the height of the waste mass above the back slope to the depth of waste mass at the back slope, or the reasonable consideration of the magnitude of the amplification factor will be conducive to the seismic design of the landfill. In addition, the results obtained by the pseudo-static and pseudo-dynamic methods were compared. 相似文献
100.
Wen-hua RUAN Mei-li HUANG Xiao-lei HE Feng ZHANG Hai-biao TAO 《Journal of Zhejiang University. Science. B》2013,14(3):253-258
Objective:To evaluate the pharmacological effects of traditional Chinese medicine,bear bile capsule and Huangqi granule,on recurrent parotitis in children.Methods:In this prospective,controlled,and randomized study,a total of 151 young children were divided into three groups:Group A included massaging the children’s parotid region and melting vitamin C in their mouth daily;Group B included swallowing bear bile capsule and Huangqi granule daily;and Group C included massages and vitamin C as prescribed in Group A,and traditional Chinese medicine as prescribed in Group B.Children were treated individually for one month and then a follow-up study was conducted for 1 to 3.5 years.Analysis of variance(ANOVA) and Ridit analysis were employed for statistical analysis.Results:The recurrence rate decreased in every group,but was significantly more in Groups B and C when compared to Group A.The recurrences significantly decreased(P<0.01) in Group B and their recovery rate was as high as 63%,significantly better than those of the other groups(P<0.01).Conclusions:Huangqi and bear bile could be a novel clinical approach for treating recurrent parotitis in children. 相似文献