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111.
The optical response of graded-index spherical metallic nanoparticles is studied in the modified long wavelength approximation with electrodynamic effects accounted for to the lowest order of the inverse of the wavelength. An effective-medium approach is adopted which leads to the conclusion that the first-order dynamical effects will enter mainly via the polarizability and not the effective dielectric function of the system. Numerical studies using various graded Drude functions show that these effects are not only significant for particles of large sizes but can also be appreciable for smaller particles with varying index profile. 相似文献
112.
埃博拉病毒属丝状病毒科,能引发动物和人出血热症状,人感染后病死率高达90%以上,目前还没有有效预防和治疗的药物和疫苗。近年来,这种烈性传染病病毒传入我国的可能性不断加大,给我国公共卫生应急体系带来新的挑战。本研究针对埃博拉病毒的最主要结构蛋白——糖蛋白(GP),构建了重组原核表达载体pET28a(+)-GP1(33~313aa)、pET28a(+)-GP1(190~313aa)、pET28a(+)-GP2(502~632aa)、pET28a(+)-sGP,以及重组真核表达载体pcDNA3.1(+)-edited GP、pcDNA3.1(+)-GP1、pcDNA3.1(+)-GP。结果表明,GP1(33~313aa)、GP1(190~313aa)和sGP能在大肠埃希菌BL21(DE3)中以包涵体的形式表达,GP、GP1和GP2能在HEK293T细胞中表达,但均不能在BHK21细胞中表达。本研究为进一步探索埃博拉病毒GP的结构和功能及GP抗体制备奠定了基础。 相似文献
113.
Sunkyung Lee Kyu Yang Yi Sung Jun Youn Byung Ho Lee Sung-eun Yoo 《Bioorganic & medicinal chemistry letters》2009,19(5):1329-1331
A series of (2-aryl-5-methylimidazol-4-ylcarbonyl)guanidines and (2-aryl-5-methyloxazol-4-ylcarbonyl)guanidines were synthesized and evaluated as NHE-1 inhibitors. The structure–activity relationships well matched those of furan derivatives, which were previously investigated. The (2,5-disubstituted)phenyl compounds showed better activities than the other analogues in both imidazole and oxazole compounds. Especially, 2-(2,5-dichlorophenyl)imidazole 52, and 2-(2-methoxy-5-chlorophenyl)imidazole 54 compounds exhibited potent cardioprotective efficacy both in vitro and in vivo as well as high NHE-1 inhibitory activities. 相似文献
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S Su N Cao J Chen F Zhao H Li M Zhao Y Wang Z Huang L Yuan H Wang G Zhang S Li 《Journal of virology》2012,86(18):10238
We report here the complete genomic sequence of an avian-origin H3N2 canine influenza A virus containing multiple mutations in farmed dogs in southern China. Phylogenetic analyses of the sequences of all eight viral RNA segments demonstrated that these are wholly avian influenza viruses of the Asia lineage. To our knowledge, this is the first report of interspecies transmission of an avian H3N2 influenza virus to domestic farm dogs under natural conditions in Southern China. The amino acid information provided herein suggests that continued study is required to determine if this virus could be established in the farm dog population and pose potential threats to public health. 相似文献
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Spray of ethrel (1000 ppm)to seedlings of double-cropping second season rice at 5-leaf stage can control plant height and root length, and consequently makes seedlings strong and tough. The ABA content and ethylene released by young seedling were significantly higher than the control. However, there were some changes: cell elongation inhibited, leaf area decreased, and leaf color became dark green, photosynthetic rate increased, translocation of photosynthetate in leaf sheath enhanced, leaf emergence was rapid. The growth of root system and root vigor were though temporarily inhibited, but slightly increased after transplantation. All these are beneficial to seedling quality, the plant growth and development after transplantation, which subsequently bring about positive effects on stimulating early heading and on increasing rice yield. 相似文献
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