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981.
LiYanping ZHANGXin WANGZhimin LUDaru HANGWei JINLi 《科学通报(英文版)》2004,49(16):1777-1778
Imbalance of redox state has been associated with human diseases, such as cardiovascular diseases, Huntington‘s disease and Alzheimer‘s disease. Catalase, an important antioxidant enzyme, decomposes H202 into O2 and H2O, therefore limiting the deleterious effect of the reactive oxygen species (ROS). Previous study showed that a C-T polymorphism, located at -844 bp from the translational start site of catalase, is strongly associated with essential hypertension in an isolated Chinese population of Xiangchang country, Anhui Province. To explore the impact of SNP-844C/T on the expression of catalase, human catalase promoters containing either SNP-844C or T variant were subcloned into the pGL3Basic luciferase vector. 相似文献
982.
Discovery of a Miaohe-type Biota from the Neoproterozoic Doushantuo Formation in Jiangkou County, Guizhou Province, China 总被引:4,自引:0,他引:4
ZHAOYuanlong CHENMeng'e PENGJin YUMeiyi HEMinghua WANGYue YANGRongjun WANGPingli ZHANGZhenhan 《科学通报(英文版)》2004,49(20):2224-2226
A megascopic algal fossil assemblage was first discovered by Ma Guogan and Chen Meng‘e in the black shales of the Neoproterozoic Doushantuo Formation in Miaohe Town, Zigui County, Hubei Province in 1978. Formal naming of the Miaohe Biota was proposed by Cheng Meng‘e and Xiao Zongzheng in 199112j, and eleven morphological genera have been previously described. including megascopic algae and putative metazoans .Ding et al. greatly expanded the scope of the Miaohe Biota to 9 phyla consisting of 140 genera, including microphytoplanctons, megascopic algae, metazoans, spongesand trace fossils. Xiao et al. further restudied this fossil assemblage, concluding that only about 18 distinct taxa could be recognized and that many Miaohe taxa are poorly defined or svnonvmous. 相似文献
983.
Photocatalytic effect of nature and modified V-bearing rutile 总被引:2,自引:0,他引:2
LUAnhuai GUOYanjun LIUJuan LIUFei WANGChangqiu LINing LIQiaorong 《科学通报(英文版)》2004,49(21):2284-2287
A natural rutile TiO2, which displays photocatalysis on degrading halohydrocarbon pollutants, was reported. The rutile contains up to 1.22% V2O5 (weight percent). Substitutions of Ti by V, as well as Fe, Cu and Zn, result in lattice distortions and defects. Grinding, heating and quenching modify the surface characteristics of ruffle, and consequently increase its photoactivity. It is found that the heating and quenching treatments enhance visible-light absorption of ruffle, especially at 1000 and 1100℃. Ground rutile is effective to degrade tetrachloroethylene and trichloroethylene. While, heating at 1000℃, and quenching at 1000 and 1100℃ distinctly improve degradation rate of samples. The special properties of the natural rutile have particular capabilities in photocatalytic oxidation, especially in degradation of halohydrocarbons. 相似文献
984.
系统科学与复杂网络研究 总被引:4,自引:0,他引:4
从模型的角度出发,分析系统科学所讨论的几类模型,总结研究这些模型的主要概念和主要方法;依据当前复杂网络研究的实际,提出系统科学和复杂网络结合研究的思路、具体方法、应注意的问题。 相似文献
985.
986.
Wen Jun Zhang Rui & Lu Xianliang . Computer Institute University of Electronic Science Technology of China Chengdu P. R. China . Datacraft Corporation Chengdu P. R. China 《系统工程与电子技术(英文版)》2005,16(1)
1.INTRODUCTION Recentanalysesofvariouspacket basednetworking showthatnetworktraffichasvariabilityovermany timescales.Itsperformancedifferswithresultsof queuetheorythatisbasedonthePoissondistribu tion.Statisticalanalysesoflargetrafficdatasetshave revealedthatthestatisticalcharacteristicsofrealtraf ficmaybebestdescribedbyself similarity.Self simi larityimpliesthepresenceoflong rangedependence (LRD)inthetraffic.Thatis,thereexistnon negli giblepositivecorrelationintheburstbehaviorofthe … 相似文献
987.
988.
At the invitation of NSFC, the DFG delegation, led by its President Prof. Ernst-Ludwig Winnacker, paida visit to China from Apr. 9 to 19, 2005. Members of the delegation include Prof. Frank Steglich, Vice Presi-dent of DFG and Dr. Axel-Hubertus Zienicke, the Deputy Secretary General, etc.Prof. Chen Yiyu, President, Prof. Zhu Zuoyan, Vice President, and Prof. Wang Jie, Vice President ofNSFC met with the delegation on April 11. Prof. Chen first briefed the delegation about the… 相似文献
989.
Lu Huapu 《中国科学基金(英文版)》2005,13(2):30-35
Satisfying the increasing traffic demand with the least amount of resource and environmental costs, the sustainable development object of urban traffic system determines that from long-term viewpoint, it is necessary to establish urban integrated traffic planning system with public transport as it is. The planning idea of Transit Oriented Development (TOD) is an important method to realize urban integrated traffic planning system. Research and practice reveal that harmony and integration is the key method to solve urban traffic problems. The integration of traffic system and land-use is the basic problem. Urban traffic development strategy with TOD provides ideas and ways to harmonize the traffic and land-use systems, which brings out a series of new research subjects and challenges in the field of traffic planning. 相似文献
990.
英国皇家科学院院士、著名科学史家李约瑟(Joseph Needham,1900-1995)博士的名字是学术界尽人皆知的,他以毕生精力研究并弘扬中国古代科学文化,架起沟通东西方文化的大桥,贡献巨大. 相似文献