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991.
992.
The biological data are scattered in various areas with various formats and they are changing continuously. Therefore, data integration becomes an important issue to provide researcher a dynamic access of data. In the data integration process, the method of extracting heterogeneous data dynamically from the data source is an essential part. Data extraction method using wrapper can provide flexibility and extensibility to an integration system. 相似文献
993.
MOTIVATION: It is a common practice in cancer microarray experiments that a normal tissue is collected from the same individual from whom the tumor tissue was taken. The indirect design is usually adopted for the experiment that uses a common reference RNA hybridized both to normal and tumor tissues. However, it is often the case that the test material is not large enough for the experimenter to extract enough RNA to conduct the microarray experiment. Hence, collecting n cases does not necessarily end up with a matched pair sample of size n. Instead we usually have a matched pair sample of size n1, and two independent samples of sizes n2 and n3, respectively, for 'reference versus normal tissue only' and 'reference versus tumor tissue only' hybridizations (n=n1 + n2 + n3). Standard statistical methods need to be modified and new statistical procedures are developed for analyzing this mixed dataset. RESULTS: We propose a new test statistic, t3, as a means of combining all the information in the mixed dataset for detecting differentially expressed (DE) genes between normal and tumor tissues. We employed the extended receiver operating characteristic approach to the mixed dataset. We devised a measure of disagreement between a RT-PCR experiment and a microarray experiment. Hotelling's T2 statistic is employed to detect a set of DE genes and its prediction rate is compared with the prediction rate of a univariate procedure. We observe that Hotelling's T2 statistic detects DE genes more efficiently than a univariate procedure and that further research is warranted on the formal test procedure using Hotelling's T2 statistic. CONTACT: bskim@yonsei.ac.kr. 相似文献
994.
Escherichia coli O157:H7 is an enteric pathogen of public health importance, which is monitored by several government agencies. Many rapid detection tests have been developed to identify foodstuff and water supplies contaminated by E. coli O157:H7. However, these methods can be time consuming (24-48 h) due to the need to culture the bacteria to confirm detection results. Fiber optic biosensors can rapidly detect pathogens from complex matrices, yet confirmation tests can take up to 10h to complete. In addition, fiber optic biosensors can also be used to reduce the impact of PCR inhibitors present in complex matrices such as food and water. This paper presents methodologies to reduce the time necessary for confirmation from 10 to about 2 h, by direct PCR of bacteria from the fiber optic waveguides without the need for culture or enrichment steps. 相似文献
995.
996.
Lee S Lee H Yi KY Lee BH Yoo SE Lee K Cho NS 《Bioorganic & medicinal chemistry letters》2005,15(12):2998-3001
A series of 4-substituted (benzo[b]thiophene-2-carbonyl)guanidines was synthesized and evaluated for the NHE-1 inhibitory activity and cardioprotective efficacy both in vitro and in vivo. Several analogs exhibited a strong inhibition on NHE-1, and which was generally well correlated with their cardioprotective efficacy. Especially the 4-nitro 20 and cyano 50 compounds excellently improved the cardiac function and reduced infarct size against ischemia/reperfusion injury. 相似文献
997.
Synthesis and structure-activity relationships of 1,2,4-triazoles as a novel class of potent tubulin polymerization inhibitors 总被引:1,自引:0,他引:1
Ouyang X Chen X Piatnitski EL Kiselyov AS He HY Mao Y Pattaropong V Yu Y Kim KH Kincaid J Smith L Wong WC Lee SP Milligan DL Malikzay A Fleming J Gerlak J Deevi D Doody JF Chiang HH Patel SN Wang Y Rolser RL Kussie P Labelle M Tuma MC 《Bioorganic & medicinal chemistry letters》2005,15(23):5154-5159
A novel triazole-containing chemical series was shown to inhibit tubulin polymerization and cause cell cycle arrest in A431 cancer cells with EC(50) values in the single digit nanomolar range. Binding experiments demonstrated that representative active compounds of this class compete with colchicine for its binding site on tubulin. The syntheses and structure-activity relationship studies for the triazole derivatives are described herein. 相似文献
998.
Kim JH Curtis-Long MJ Seo WD Lee JH Lee BW Yoon YJ Kang KY Park KH 《Bioorganic & medicinal chemistry letters》2005,15(19):4282-4285
We designed and synthesized polyhydroxylated pyrrolidines 1-12 from L-tyrosine, L-phenylalanine, and D-tyrosine through iodine-mediated intramolecular cyclization followed by Woodward-Prevost reaction. The synthetic polyhydroxylated pyrrolidines were identified with structure-based inhibitory activity and selective inhibitory activity against alpha-rhamnosidase. (2S,3S,4R)-deacetyl anisomycin 7 was the best inhibitor among the 12 polyhydroxylated pyrrolidines because it possesses the same stereoconfiguration at C1, C2, C3 as alpha-L-rhamnopyranoside. An investigation into the nature of the inhibition showed that the synthetic pyrrolidines are competitive inhibitors. They also did not have remarkable inhibitory activity against seven glycosidases (alpha-glucosidase, alpha-mannosidase, alpha-amylase, beta-glucosidase, beta-galactosidase, beta-amylase, and invertase). 相似文献
999.
1000.