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61.
A series of neovibsanin A and B derivatives and lower homologues were synthesized to study their neurotrophic ability with PC12 cells. 4,5-Bis-epi-neovibsanin A displayed prominent ability to induce neurite outgrowth compared to control cultures. Herein we describe the total synthesis of 4,5-bis-epi-neovibsanin A and B as well as comparing the biological activity of several neovibsane derivatives. 相似文献
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Qi Wang Hongjun Ni Annette Pietzsch Franz Hennies Yongping Bao Yimin Chao 《Journal of nanoparticle research》2011,13(1):405-413
Water-dispersible silicon nanoparticles (Si-NPs) are desirable for applications in biological techniques. A simplified method
to synthesize such particles is reported here. The resulting Si-NPs are water-dispersible and luminescent. Under the excitation
of UV light, the Si-NPs emit strong red light with a peak maximum at 606 nm and a quantum yield of 6%. They are highly stable,
and remain so over several weeks. Fourier Transform Infrared (FTIR) spectroscopy shows a visible Si–CH2 scissoring vibration mode. Furthermore, the surface chemical bondings were confirmed by X-ray photoelectron spectroscopy
(XPS). In the Si2p and C1s core levels, Si–C components are observed. The diameters of the synthesized Si-NPS as measured by atomic force microscope (AFM) are approximately
5 nm. Furthermore, the nanoparticles can be taken up by cultured cells. Fluorescence images of Si-NPs within MCF-7 human breast
cancer cells show they are distributed throughout the cell tissue. 相似文献
64.
Gaetano Assanto Catherine García-Reimbert Antonmaria A. Minzoni Noel F. Smyth Annette L. Worthy 《Physica D: Nonlinear Phenomena》2011,240(14-15):1213-1219
We investigate the interaction of three optical solitary waves propagating with angular momentum in bulk nematic liquid crystals. The resulting cluster of solitary waves, or nematicons, is shown to orbit about its common centre of “mass”. An elongated isosceles triangle configuration is derived, this solution being the equivalent of the Lagrange solution of Newtonian gravitation. This triangle solution is found to be stable owing to diffractive radiation. A modulation theory explains the existence of the triangle solution as due to the non-monotonicity of an effective potential for the interaction of the solitary waves. This modulation theory also gives good agreement with numerical solutions for the trajectories of the nematicons in the three colours. Finally, it is shown that a cut-off in the shed diffractive radiation prevents the break-up of the triangle due to radiative losses. 相似文献
65.
Dipl.‐Pharm. Christian Wölk Dr. Simon Drescher Dr. Annette Meister Prof. Dr. Alfred Blume Prof. Dr. Andreas Langner Prof. Dr. Bodo Dobner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(38):12824-12838
A series of novel malonic acid diamides (second generation) with two long hydrophobic alkyl chains and an alkaline polar head group was synthesised and characterised as a new class of amino‐functionalised lipids. These peptide‐mimic lipids are suitable for polynucleotide transfer. The lipids bear a novel backbone consisting of a lysine unit and a malonic acid unit. Six different head‐group structures, which vary in size and number of amino groups that can be protonated, were attached to the backbone structure. Furthermore, different alkyl chains were used to build the lipophilic part (namely tetradecyl, hexadecyl, and oleyl). Phase transitions of the new compounds in aqueous dispersions at pH 10 were analysed and discussed in terms of head group and alkyl chain variations. The shape and size of the formed aggregates of selected lipid dispersions were investigated by dynamic light scattering and transmission electron microscopy. 相似文献
66.
Direct measurements of the in-plane London penetration depth λ L have recently been performed on high-temperature superconducting copper oxides by a new low-energy muon spin rotation technique. The results show that λ L is isotope dependent, evidencing unconventional electron–phonon interactions as its source. The data are interpreted here in terms of polaronic effects on the single-particle energies, which leads to level shifts and exponential band narrowing. Good agreement with the experimental data is obtained. 相似文献
67.
Dr. Wei Liu Dr. Paramaconi Rodriguez Dr. Lars Borchardt Dr. Annette Foelske Dr. Jipei Yuan Anne‐Kristin Herrmann Dr. Dorin Geiger Dr. Zhikun Zheng Prof. Stefan Kaskel Dr. Nikolai Gaponik Dr. Rüdiger Kötz Prof. Thomas J. Schmidt Prof. Alexander Eychmüller 《Angewandte Chemie (International ed. in English)》2013,52(37):9849-9852
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