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991.
Yu Dahai Sun Sanyuan Lu Hong Zhao Di Zhou Chong 《Cell biochemistry and biophysics》2013,67(1):175-180
Esophageal carcinoma (EC) is an aggressive and the third most common cancer of the digestive tract with poor prognosis. Replication protein A (RPA) is critically required for DNA replication and its elevated expression has been observed in many malignant tumors. In this study, we investigated the expression of RPA1 and RPA2, subunits of RPA, and assessed their prognostic value in EC patients. We analyzed immunohistochemically the expression of RPA1 and RPA2 proteins in 48 EC resection specimens in relation with clinicopathological parameters and survival. We observed a significant elevated (P < 0.001) RPA1 and RPA2 expressions (labeling index) in the tumor than adjacent non-tumor tissues. In addition, both RPA1 and RPA2 labeling index in lymph node metastasis patients was significantly higher (both P = 0.000) than patients without lymph node metastasis. However, RPA1 and RPA2 labeling index in early stage was significantly lower (P = 0.000 and P = 0.002, respectively) than that of late stage EC patients. Importantly, patient’s survival at early stage was significantly higher (P = 0.016) than late stage EC and lymph node metastasis and RPA1 expression was associated with adverse patient’s outcome in multivariate analysis (P < 0.05 and P < 0.00, respectively). In conclusion, RPA1 could be a useful prognostic indicator in patients with esophageal carcinoma and might be a future attractive therapeutic target for regulation by tumor suppressors. 相似文献
992.
Industrial production can produce large amounts of harmful by-products, causing serious pollution and ecological risk. In addition, if government regulations are subjected into the industries, huge cost risk will be faced. This article adopts a two-stage slack-based undesirable-output data envelope analysis (DEA) model to measure the eco-efficiency of China. In the first stage, we analyze the eco-efficiency of each province of China, and in the second stage, we employed a truncated bootstrap method to understand the determinants of eco-efficiency. The results indicate that whereas the eco-efficiency of the eastern region was the highest, that of the western region was the lowest. The western region's economy lagged behind that of other regions, and its environment suffered from heavy pollution. It was found that the level of industrialization did not contribute to eco-efficiency. However, promotion of the service industry, investment for the environment, and regional innovation have positive effects on eco-efficiency. 相似文献
993.
Min Wang Heng Jiang Zhiguo Song Hong Gong 《Preparative biochemistry & biotechnology》2013,43(4):372-379
Abstract An efficient synthesis of 3,4-dihydropyrimidin-2(1H)-ones from aldehydes, 1,3-dicarbonyl compounds, and urea using copper nitrate under refluxing temperature in ethanol was described. Compared with other Lewis copper salts, copper nitrate proved to be the most efficient. The advantages of the new method were good yields (61–93%), short reaction time (0.4–3 h), and inexpensive catalyst. 相似文献
994.
995.
996.
Yi Luo Min Wang Zhonghua Pang Fengtao Jiang Jiangning Chen Junfeng Zhang 《The journal of gene medicine》2013,15(11-12):441-452
997.
Hye Jung Choi Jeoung-Yoon Seo Su Mi Hwang Yong-Ill Lee Yong Kee Jeong Ja-Young Moon Woo Hong Joo 《Biotechnology and Bioprocess Engineering》2013,18(5):1000-1007
Bacterial strains growing in river sediments were screened to identify an organic solvent-tolerant strain of Pseudomonas. Using this screen, Pseudomonas sp. BCNU 106 was isolated on the basis of its ability to grow on benzene, toluene, ethylbenzene, and three xylene isomers, o-, m- and p-xylene, as its sole carbon source. BCNU 106 was identified as a gram-negative, rod-shaped aerobic and mesophilic bacterium, which grew in liquid media containing high concentrations of organic solvents. 16S rDNA analysis classified BCNU 106 as a new member of the genus Pseudomonas. BCNU 106 was distinguishable from other Pseudomonas strains that are tolerant to organic solvents in that the isolate had the ability to utilize all three xylene isomers as well as benzene, toluene and ethylbenzene. The unique properties of the isolate such as solvent-tolerance and the ability to degrade xylene isomers may have important implications for the efficient treatment of solvent wastes. 相似文献
998.
Changon Seo Yun-Hyeok Choi Jong Seog Ahn Joung Han Yim Hong Kum Lee 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1133-1137
The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory natural products, the MeOH extract of the dried sample of the Antarctic lichen Umbilicaria antarctica was found to exhibit significant inhibitory effect, and the bioassay-guided fractionation and purification afforded three related lichen metabolites 1-3. Compounds 1-3 were identified as gyrophoric acid (1), lecanoric acid (2), and methyl orsellinate (3) mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 3.6 ± 0.04 μM, 31 ± 2.7 μM, and 277 ± 8.6 μM, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compound 1 suggested that the compound inhibited PTP1B activity in a non-competitive manner. 相似文献
999.
J. Isaksson T. Maltseva P. Agback X. Luo A. Kumar E. Zamaratski 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1593-1596
Abstract The impact of intramolecular stereoelectronic effects has been examined by comparison of the solution structures of natural oligo-DNA duplex, 5′(1C2G3C4G5A6A7T8T9C10G11C12G)2 3′, and its carbocyclic-nucleotide analogues in which the pentose sugar in 2′-dA residue is replaced with its carbocyclic counterpart (i.e. 2′-deoxyaristeromycin). Based on the NMR evidences, it has been shown, that 2′-deoxyaristeromycin analog exists in a dynamic equilibrium between the two forms of duplexes, one with W-C bp and the second with Hoogsteen bp in ca 1:1 ratio at lower temperature (below 35°C) and as hairpin at higher temperature (from ~40° – 60°C). 相似文献
1000.
The discovery of threosyl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) as a potent anti-HIV agent has led to the synthesis and biological evaluation of 5 ′-deoxyversions of threosyl phosphonate nucleosides from 1,4-dihydroxy-2-butene. The synthesized nucleoside phosphonic acid analogues 14 and 19 were tested for anti-HIV activity as well as cytotoxicity. The adenine analogue 14 exhibits moderate in vitro anti-HIV-1 activity (EC50 = 12.6 μM). 相似文献