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排序方式: 共有216条查询结果,搜索用时 531 毫秒
31.
DNA damage repair through the nucleotide excision repair (NER) pathway is one of the major reasons for the decreased antitumor efficacy of platinum‐based anticancer drugs that have been widely applied in the clinic. Inhibiting the intrinsic NER function may enhance the antitumor activity of cisplatin and conquer cisplatin resistance. Herein, we report the design, optimization, and application of a self‐assembled lipid nanoparticle (LNP) system to simultaneously deliver a cisplatin prodrug together with siRNA targeting endonuclease xeroderma pigmentosum group F (XPF), a crucial component in the NER pathway. The LNP is able to efficiently encapsulate both the platinum prodrug and siRNA molecules with a tuned ratio. Both platinum prodrug and XPF‐targeted siRNA are efficiently carried into cells and released; the former damages DNA and the latter specifically downregulates both mRNA and protein levels of XPF to potentiate the platinum drug, leading to enhanced expression levels of apoptosis markers and improved cytotoxicity in both cisplatin‐sensitive and ‐resistant human lung cancer cells. Our results demonstrate an effective approach to utilize a multi‐targeted nanoparticle system that can specifically silence an NER‐related gene to promote apoptosis induced by cisplatin, especially in cisplatin‐refractory tumors. 相似文献
32.
This work proposes a new texturing technique of monocrystalline silicon surface for solar cells with sodium hypochlorite. A mixed solution consisting of 5 wt% sodium hypochlorite and 10 vl% ethanol has been found that results in a homogeneous pyramidal structure, and an optimal size of pyramids on the silicon surface. The textured silicon surface exhibits a lower average reflectivity (about 10.8%) in the main range of solar spectrum (400–1000 nm). 相似文献
33.
原子力与光子扫描隧道组合显微镜 总被引:3,自引:0,他引:3
介绍了超高分辨光于扫描隧遭显微镜(PSTM)的计冗历程,为解决第一代(单光束照明)光千扫捕隧逼显傲镜中存在人为假象和样品光学图像与形貌图像难于分离两个难题,用“对称双光束照明方法消假象,用原子力与光子扫描隧道组合显微镜(AF/PSTM)图像分解方法分离样品光学透过率、折射率与形貌图像。研制成功新一代原子力与光子扫描隧道组合显微镜(AF/PSTM)样机。该样机在一次扫描中已获得两幅原子力显微镜图像(形貌与相位)和两幅光学图像(透过率和折射率),有效地减少了假象,分解了样品光学折射率、透过率与形貌图像。 相似文献
34.
Linfeng Hu Renzhi Ma Dr. Tadashi C. Ozawa Dr. Takayoshi Sasaki Prof. 《Angewandte Chemie (International ed. in English)》2009,48(21):3846-3849
Caught on film : A semitransparent and intensely luminescent monolayer film of oriented Gd2O3:0.05 Eu platelet crystallites is fabricated by annealing the precursor hydroxide film (see scheme). The photoluminescence properties of the as‐transformed film are greatly improved over those of the hydroxide film, and are much more pronounced than those of the corresponding Gd2O3:0.05 Eu powder.
35.
A novel rhodamine derivative (Rh-C), synthesized by the reaction of rhodamine ethylenediamine and cinnamoyl chloride, was evaluated as a chemoselective Hg(2+) ion sensor. Addition of Hg(2+) to an ethanol aqueous solution of the Rh-C resulted in a color change from colorless to obvious pink color together with distinctive changes in UV-vis absorption spectrum and fluorescence spectrum. However, other common alkali-, alkaline earth-, transition- and rare earth metal ions induced no or minimal spectral changes. The interaction of Hg(2+) and sensor Rh-C was proven to adopt a 1:1 binding stoichiometry and the recognition process is reversible. The chemosensor displayed a linear response to Hg(2+) in the range of 0.4-5?μM with a detection limit of 7.4?×?10(-8)?M. The sensor Rh-C was also successfully applied to the imaging of Hg(2+) in HL-7702 cells. 相似文献
36.
Y Wen L Xu C Li H Du L Chen B Su Z Zhang X Zhang Y Song 《Chemical communications (Cambridge, England)》2012,48(67):8410-8412
DNA assembles that can perform "OR" and "AND" logic gate operations were fabricated. The feasibility of intelligent logic controlled release was demonstrated through the controlled organization of gold nanoparticles on the surface of mesoporous silica by stimuli-induced structural transformation of DNA ensembles. 相似文献
37.
Dr. Xiao-Lu Wang Dr. Jia-Yue Tian Xuan-Chen Guo Prof. Dr. Fu-Qiang Zhang Dr. Linfeng Liang Prof. Dr. Xian-Ming Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(11):3753-3760
Dimethyl sulfoxide (DMSO) is a universally used solvent in various synthetic reactions, and trace amounts of DMSO residual are often seen on the surface of chemical product. It is difficult to quickly determine whether the residual DMSO is washed completely. This work reports a CdII metal–organic framework (MOF) SXU-4 which can detect trace amounts of DMSO in various solvents. Fluorescence experiments reveal its turn-on fluorescence effect toward DMSO with high selectivity and sensitivity, indicating that it can be used as an effective luminescent probe for rapid chemical product purity detection by testing the washing solution. Crystallographically characterized DMSO loaded SXU-4 (DMSO@ SXU-4 ), in combination with computational results uncover that the enhanced DMSO–MOF conjugation through multiple DMSO–MOF supramolecule interactions and charge rearrangement are the main causes of fluorescence intensification. 相似文献
38.
39.
The solubility of calcium isosaccharinate Ca(ISA)2(c) was determined at 23°C as a function of pH (1–14) and calcium ion molality (0.03–0.52). The similarity of solubility from the over- and undersaturation directions for different equilibration periods indicated that equilibrium in these solutions was reached rapidly (< 7 days) and that these data can be used to develop thermodynamic equilibrium constants. The solubility data were interpreted using the Pitzer ion–interaction model. The logarithms of the thermodynamic equilibrium constants determined from these data were 1.30 for the dominant reaction at pH < 4.5 [Ca(ISA)2(c) + 2H+ Ca2+ + 2HISA(aq)], and –2.22 for the dominant reaction at 4.5 [Ca(ISA)2(c)+ Ca(ISA)2(aq)]. In addition, the logarithm of the dissociation constant of HISA [HISA(aq) ISA- + H+] was calculated to be –4.46. 相似文献
40.
The cationic polymerizations of 1, 3-pentadiene were initiated by AlCl_3 in n-hexaneat 30℃ in the presence of alkyl halides, i.e., tert-butyl chloride, tert-butyl bromide andisobutyl chloride. The effects of these halides on the polymer yield, molecular weight,crosslinking reaction, cyclization and polymer microstructure, have been investigated. Twomain side reactions, crosslinking and cyclization, were suppressed and reduced by theaddition of the halides. The proportion of 1, 4 units of polymer chains was increasedby the presence of the halides, which reduced the polymer yield and the molecular weightof polymers. 相似文献