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31.
32.
Ken-ichi Kanno Shun-ichi Naoe Seiji Mukai Yoshio Nakai Takeshi Miyanaga 《Solid State Communications》1973,13(9):1325-1328
The absorption spectra of CdCl2 and CdBr2 single crystals doped with cuprous or cupric halides were measured. Optical bleaching of the absorption bands due to Cu+ gives rise to new absorption bands which suggest the conversion of Cu+→Cu2+. This was confirmed also by detecting the growth in ESR signals characteristic of Cu2+ centers. 相似文献
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Hiroshi Kogen Kiyoshi Tomioka Shun-ichi Hashimoto Kenji Koga 《Tetrahedron letters》1980,21(41):4005-4008
Procedures for the asymmetric synthesis of 1,2-disubstituted cycloalkanecarboxaldehydes () having assymetric tertiary and quaternary carbon atoms in vicinal positions from the corresponding cycloalkenecarboxaldehydes () in high diastereomeric and enantiomeric purities are described. 相似文献
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Thermo‐triggered Release of CRISPR‐Cas9 System by Lipid‐Encapsulated Gold Nanoparticles for Tumor Therapy 下载免费PDF全文
Dr. Peng Wang Dr. Lingmin Zhang Prof. Wenfu Zheng Dr. Liman Cong Zhaorong Guo Yangzhouyun Xie Le Wang Rongbing Tang Qiang Feng Prof. Yoh Hamada Prof. Kohsuke Gonda Prof. Zhijian Hu Prof. Xiaochun Wu Prof. Xingyu Jiang 《Angewandte Chemie (International ed. in English)》2018,57(6):1491-1496
CRISPR/Cas9 system is a powerful toolbox for gene editing. However, the low delivery efficiency is still a big hurdle impeding its applications. Herein, we report a strategy to deliver Cas9‐sgPlk‐1 plasmids (CP) by a multifunctional vehicle for tumor therapy. We condensed CPs on TAT peptide‐modified Au nanoparticles (AuNPs/CP, ACP) via electrostatic interactions, and coated lipids (DOTAP, DOPE, cholesterol, PEG2000‐DSPE) on the ACP to form lipid‐encapsulated, AuNPs‐condensed CP (LACP). LACP can enter tumor cells and release CP into the cytosol by laser‐triggered thermo‐effects of the AuNPs; the CP can enter nuclei by TAT guidance, enabling effective knock‐outs of target gene (Plk‐1) of tumor (melanoma) and inhibition of the tumor both in vitro and in vivo. This AuNPs‐condensed, lipid‐encapsulated, and laser‐controlled delivery system provides a versatile method for high efficiency CRISPR/Cas9 delivery and targeted gene editing for treatment of a wide spectrum of diseases. 相似文献
37.
An extended MOMBE growth kinetics model is proposed, based on the Robertson model, to explain both the GaAs growth rate variation and modulated beam mass spectroscopy data reported by Martin and Whitehouse. In this model, we assume that (1) MEGa molecules react with ethyl-radicals to form DEGa, (2) excessive group-V molecules on the surface suppress the decomposition of DEGa and enhance the desorption of DEGa, (3) reaction of DEGa with ethyl-radicals to form TEGa is negligible, and (4) effective surface coverage of excessive group-V atoms during growth is determined by the double layer adsorption model including desorption parameters for group-V molecules. The first assumption (1) is found to be a dominant process to explain the behaviour of DEGa desorption at high temperatures. This model can reproduce the dependences of both growth rate and desorbing rate of Ga alkyls on substrate temperature during GaAs MOMBE growth. The use of Sb instead of As produces a significant change in the growth rate variation with substrate temperature and group-V flux for the growth of GaSb, in spite of the use of the same TEGa flow rate. This can be rationalized by the difference in the desorption parameters for Sb and As. 相似文献
38.
Phonon behavior in the strained (InAs)m/(GaAs)n ultrathin superlattices grown by molecular beam epitaxy has been investigated by means of Raman scattering spectroscopy. The phonon frequency in the GaAs layers shifts toward lower energy with increasing InAs layer thickness under fixed thickness of GaAs layers. The frequency in the InAs layers does not change significantly, as deduced from the behavior of the InAs-like mode in InxGa1−xAs alloys. These observed results are phenomenologically discussed on the basis of the combined effect of phonon confinement in the respective layer and stress at the alternating interfaces. Furthermore, a large softening of the phonon confined in the GaAs layers decreases the frequency gap, resulting in traveling of the optical phonons confined in both layers. The strain at the interfaces is estimated by an empirical method, i.e., by comparing the frequency in the superlattice and in the alloy of equivalent composition. In the InxGa1−xAs alloys, the composition dependence of the mode frequency is considered as being due to the local strain. The group III elements are considered to be in the local strain state from an extended X-ray absorption fine structure (EXAFS) analysis. 相似文献
39.
Henares TG Funano S Terabe S Mizutani F Sekizawa R Hisamoto H 《Analytica chimica acta》2007,590(2):173-179
Gastrodin is a bioactive constituent of rhizome in Gastrodia elata Blume (Orchidaceae) The aim of this study is to develop a rapid and sensitive liquid chromatographic method coupled to microdialysis sampling system to measure the unbound of gastrodin in rat blood, brain and bile. Microdialysis probes were simultaneously inserted into the jugular vein, brain striatum and bile duct of each anesthetized rat for sampling after the administration of gastrodin (100 or 300 mg kg−1) through the femoral vein. Separation of unbound gastrodin from various biological fluids was applied to an RP-select B column (250 mm × 4.6 mm i.d., 5 μm). The mobile phase consisted of acetonitrile–50 mM potassium dihydrogen phosphate buffer–triethylamine (5:95:0.1, v/v/v, adjusted to pH 2.5 with orthophosphoric acid) with a flow rate of 1 mL min−1. The UV detector wavelength was set at 221 nm. Fifteen minutes after the administration, the gastrodin reached the peak concentration in brain and bile. In addition, the results indicate that gastrodin penetrates the blood-brain barrier (BBB) and goes through hepatobiliary excretion. 相似文献
40.
Ishiuchi S Sakai M Tsuchida Y Takeda A Kawashima Y Dopfer O Müller-Dethlefs K Fujii M 《The Journal of chemical physics》2007,127(11):114307
IR spectra of phenol-Arn (PhOH-Arn) clusters with n=1 and 2 were measured in the neutral and cationic electronic ground states in order to determine the preferential intermolecular ligand binding motifs, hydrogen bonding (hydrophilic interaction) versus pi bonding (hydrophobic interaction). Analysis of the vibrational frequencies of the OH stretching motion, nuOH, observed in nanosecond IR spectra demonstrates that neutral PhOH-Ar and PhOH-Ar2 as well as cationic PhOH+-Ar have a pi-bound structure, in which the Ar atoms bind to the aromatic ring. In contrast, the PhOH+-Ar2 cluster cation is concluded to have a H-bound structure, in which one Ar atom is hydrogen-bonded to the OH group. This pi-->H binding site switching induced by ionization was directly monitored in real time by picosecond time-resolved IR spectroscopy. The pi-bound nuOH band is observed just after the ionization and disappears simultaneously with the appearance of the H-bound nuOH band. The analysis of the picosecond IR spectra demonstrates that (i) the pi-->H site switching is an elementary reaction with a time constant of approximately 7 ps, which is roughly independent of the available internal vibrational energy, (ii) the barrier for the isomerization reaction is rather low(<100 cm(-1)), (iii) both the position and the width of the H-bound nuOH band change with the delay time, and the time evolution of these spectral changes can be rationalized by intracluster vibrational energy redistribution occurring after the site switching. The observation of the ionization-induced switch from pi bonding to H bonding in the PhOH+-Ar2 cation corresponds to the first manifestation of an intermolecular isomerization reaction in a charged aggregate. 相似文献