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911.
Ji-Sen Jiang Zhi-Feng Gan Yong Yang Bing Du Min Qian Ping Zhang 《Journal of nanoparticle research》2009,11(6):1321-1330
Preparation and characterization in vitro and in vivo of a novel magnetic fluid based on starch-coated magnetite nanoparticles
functionalized with homing peptide is reported in this paper. Precursory magnetic fluids stabilized with starch were prepared,
in a polymeric starch matrix, by controlled chemical coprecipitation of magnetite phase from aqueous solutions. The average
hydrodynamic diameter of starch-coated iron oxide nanoparticles (SIONs) was 46 nm. As a homing peptide, A54 is the most effective
peptide specific to the human hepatocellular carcinoma cell line BEL-7402. Final magnetic fluids were obtained through chemical
coupling of homing peptide labeled with 5-carboxyl-fluorescein (FAM-A54) and SIONs. Magnetic measurements showed the saturation
magnetization value of SIONs amounted to 45 emu/g and the FAM-A54-coupled SIONs showed a good magnetic response in magnetic
field. The results of experiments in vitro and in vivo showed that SIONs were endowed with specific affinity to corresponding
tumor cells after coupling with FAM-A54 and the FAM-A54-coupled SIONs could be accumulated in the tumor tissue with more efficiency
than individual magnetic targeting or biomolecular targeting. This novel magnetic fluid with dual function has great potential
applications in diagnostics and therapeutics of human tumor such as drug targeting, magnetic hyperthermia, and magnetic resonance
imaging. 相似文献
912.
Banach空间的型与独立Banach空间值随机变量序列的不等式 总被引:3,自引:0,他引:3
本文建立了独立B值随机变量序列部分和的极大值函数S*与p方根函数S(p,X)的分布函数不等式与矩不等式,讨论了这些不等式的成立与Banach空间的p型与q余型的关系,同时给出了与Hilbert空间同构的Banach空间的特征。 相似文献
913.
Guo-Bo Xu Qin-Feng Zhu Zhen Wang Chun-Li Zhang Xin Yang Jin-Juan Zhang Fu-Rui Wang Jun Liu Meng Zhou Yong-Lin Wang Xun He Li-She Gan Shang-Gao Liao 《Molecules (Basel, Switzerland)》2021,26(16)
Pseudostellaria heterophylla is used in China not only as a functional food but also as an herb to tonify the spleen, enhance immunity, and treat palpitation. Our previous investigation showed that a fraction enriched in glycosides obtained from the roots of P. heterophylla possessed pronounced protective effects on H9c2 cells against CoCl2-induced hypoxic injury. However, the active compounds responsible for the observed effects were still unknown. In the current investigation, pseudosterins A–C (1–3), three new alkaloids with a 1-ethyl-3-formyl-β-carboline skeleton, together with polydatin, have been isolated from the active fraction. Their structures were elucidated on the basis of spectroscopic analysis and quantum chemical calculations. The four compounds showed cardioprotective effects against sodium hydrosulfite-induced hypoxia-reoxygenation injury in H9c2 cells, with the three alkaloids being more potent. This is also the first report of alkaloids with a β-carboline skeleton isolated from P. heterophylla as cardioprotective agents. 相似文献
914.
Incoherent interaction between one- and two-dimensional solitons in noncentrosymmetric photorefractive media 下载免费PDF全文
The incoherent interaction between solitons with different
transverse dimensions in a noncentrosymmetric photorefractive
crystal is studied both in theory and in experiment. An anomalous
incoherent interaction between one- and two-dimensional solitons,
whose attractive and repulsive effects depend on the soliton
separation, is numerically demonstrated by employing an anisotropic
model. By launching a one-dimensional green beam and a
two-dimensional red beam into a biased SBN:60 crystal, the
hybrid-dimensional soliton interaction is performed. The
experimental results are in good agreement with the numerical
ones. 相似文献
915.
Huidan Zeng Guorong Chen Jianrong Qiu Xiongwei Jiang Congshan Zhu Fuxi Gan 《Journal of Non》2008,354(12-13):1155-1158
We report on three-dimensional precipitation of Au nanoparticles in gold ions-doped silicate glasses by a femtosecond laser irradiation and further annealing. Experimental results show that PbO addition plays the double roles of inhibiting hole-trapped centers generation and promoting formation and growth of gold nanoparticles. Additionally, glass containing PbO shows an increased non-linear absorption after femtosecond laser irradiation and annealing. The observed phenomena are significant for applications such as fabrications of three-dimensional multi-colored images inside transparent materials and three-dimensional optical memory, and integrated micro-optical switches. 相似文献
916.
利用时间分辨Kerr旋光技术测量低温下稀磁半导体Ga0.937Mn0.063As中光注入极化载流子的自旋进动信号,并观察到自旋极化载流子的有效g因子值随外磁场的增强而增大的反常现象.这归结于磁场导致局域化空穴转化为非局域化空穴,从而使自发磁化强度增强,有效g因子值增大.基于此物理图像,进一步给出了(Ga,Mn)As的有效g因子与外磁场的关系式. 相似文献
917.
918.
We explore a novel mechanism for slowing down THz waves based on metallic grating structures with graded depths, whose dispersion curves and cutoff frequencies are different at different locations. Since the group velocity of spoof surface plasmons at the cutoff frequency is extremely low, THz waves are actually stopped at different positions for different frequencies. The separation between stopped waves can be tuned by changing the grade of the grating depths. This structure offers the advantage of reducing the speed of the light over an ultrawide spectral band, and the ability to operate at various temperatures, but demands a stringent requirement for the temperature stability. 相似文献
919.
Yu. P. Sukhorukov E. A. Gan’shina A. R. Kaul’ O. Yu. Gorbenko N. N. Loshkareva A. V. Telegin M. S. Kartavtseva A. N. Vinogradov 《Technical Physics》2008,53(6):716-721
Sm0.55Sr0.45MnO3/Nd0.55Sr0.45MnO3 heterostructure consisting of layers with different Curie temperatures is studied. By comparing data for IR transmission,
resistivity, magnetotransmission, magnetoresistance, and Kerr effect measured on the side of the film and substrate, the Curie
temperatures of the layers are determined and the contributions of the layers to the magnetoresistance and magnetotransmission
are estimated. A weak temperature dependence of the magnetotransmission and magnetoresistance makes manganites with a colossal
magnetoresistance and magnetotransmission candidate materials for devices without temperature stabilization. 相似文献
920.
用变分法研究高阶色散和五阶非线性对高斯脉冲在光纤中传输特性的影响 总被引:10,自引:1,他引:9
从修正的非线性薛定谔方程出发,采用变分法,导出了在高阶色散和五阶非线性共同作用情况下高斯型脉冲参量随传输距离的演化方程组;求出了振幅与脉宽、频率与啁啾、脉宽与啁啾之间的三个重要约束关系;并进一步得出了脉宽随传输距离演化的解析解和脉冲中心位置随传输距离的演化规律;描绘了高阶色散和五阶非线性下,脉宽随传输距离演化的图形.结果表明:光纤中的高阶色散和五阶非线性都会影响高斯型脉冲各个参量的演化,但脉宽和振幅间的绝热关系并未改变.高阶色散使高斯型脉冲的脉宽展宽,五阶非线性使高斯型脉冲的脉宽压缩,它们对脉宽或初始啁啾的影响可以在一定程度上抵消,从而有可能使脉冲近似实现保形传输. 相似文献