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1.
2.
Xiao-Yan He Xiao-He Ren Yan Peng Jian-Ping Zhang Shu-Lun Ai Bo-Ya Liu Chang Xu Si-Xue Cheng 《Advanced materials (Deerfield Beach, Fla.)》2020,32(17):2000208
Effective reversal of tumor immunosuppression is of critical importance in cancer therapy. A multifunctional delivery vector that can effectively deliver CRISPR-Cas9 plasmid for β-catenin knockout to reverse tumor immunosuppression is constructed. The multi-functionalized delivery vector is decorated with aptamer-conjugated hyaluronic acid and peptide-conjugated hyaluronic acid to combine the tumor cell/nuclear targeting function of AS1411 with the cell penetrating/nuclear translocation function of TAT-NLS. Due to the significantly enhanced plasmid enrichment in malignant cell nuclei, the genome editing system can induce effective β-catenin knockout and suppress Wnt/β-catenin pathway, resulting in notably downregulated proteins involved in tumor progression and immunosuppression. Programmed death-ligand 1 (PD-L1) downregulation in edited tumor cells not only releases the PD-1/PD-L1 brake to improve the cancer killing capability of CD8+ T cells, but also enhances antitumor immune responses of immune cells. This provides a facile strategy to reverse tumor immunosuppression and to restore immunosurveillance and activate anti-tumor immunity. 相似文献
3.
Kai Wang Li Jiang Xiang-Xi Ye Jian-Ping Liang Chao-Wen Li Fang Liu Zhi-Jun Li 《核技术(英文版)》2021,32(12):77-88
In this study,pure Ni was demonstrated to pro-tect the GH3535 alloy from Te vapor corrosion because of its strong absorption capacity.Severe Te corrosion of a single GH3535 alloy sample occurred in Te vapor at 700℃,which manifested as complex surface corrosion products and deep intergranular cracks.However,when pure Ni and the GH3535 alloy were put together in the vessel,the GH3535 alloy was completely protected from Te corrosion at the expense of the pure Ni.Thermody-namic calculations proved that the preferential reaction between pure Ni and Te vapor reduced the activity of Te vapor considerably,preventing the corrosion of the GH3535 alloy.Our study reveals one potential approach for protecting the alloys used in molten-salt reactors from Te corrosion. 相似文献
4.
Hang Lin Wei Zhang Ze-Xi Dong Ting Gu Nian-Guang Li Zhi-Hao Shi Jun Kai Cheng Qu Guan-Xiong Shang Yu-Ping Tang Fang Fang He-Min Li Jian-Ping Yang Jin-Ao Duan 《International journal of molecular sciences》2015,16(4):7587-7594
Scutellarin (1) has been used for the treatment of angina pectoris, cerebral infarction and coronary heart disease with a large market share in China. Pharmacokinetic studies on scutellarin showed that scutellarin (1) is readily converted into its metabolites in vivo. In this paper, a new and practical synthetic method for the synthesis of 6-O-methyl-scutellarein (3) (one metabolite of scutellarin in vivo) is reported. The benzyl bromide was firstly used to selectively replace the acetyl group at C-7 in 7, and was then used to protect the hydroxy groups at C-4'' in 10, 6-O-methyl-scutellarein (3) is obtained in high yield through these methods. 相似文献
5.
Gaussian beam migration (GBM) is an effective
and robust depth seismic imaging method, which
overcomes the disadvantage of Kirchhoff migration in
imaging multiple arrivals and has no steep-dip limitation of
one-way wave equation migration. However, its imaging
quality depends on the initial beam parameters, which can
make the beam width increase and wave-front spread with
the propagation of the central ray, resulting in poor
migration accuracy at depth, especially for exploration
areas with complex geological structures. To address this
problem, we present an adaptive focused beam method for
shot-domain prestack depth migration. Using the information
of the input smooth velocity field, we first derive an
adaptive focused parameter, which makes a seismic beam
focused along the whole central ray to enhance the wavefield
construction accuracy in both the shallow and deep
regions. Then we introduce this parameter into the GBM,
which not only improves imaging quality of deep reflectors
but also makes the shallow small-scale geological structures
well-defined. As well, using the amplitude-preserved
extrapolation operator and deconvolution imaging condition,
the concept of amplitude-preserved imaging has been
included in our method. Typical numerical examples and
the field data processing results demonstrate the validity
and adaptability of our method. 相似文献
6.
7.
In the present work, ribbon and 2-mm rod samples of Mg-Zn-Ca-Mn alloys were prepared by meltspinning and copper mold injection methods, respectively.Effects of Mn doping on glass-forming ability and corrosion performance in simulated body fluid of Mg_(65)Zn_(30)Ca_5 alloy were studied through X-ray diffraction, scanning electron microscopy, differential scanning calorimeter, and electrochemical and immersion tests. Results show that with the Mn addition increasing, all the ribbon samples are completely in amorphous state. However, the microstructure of 2-mm rod samples transfers from fully amorphous for the Mn-free alloy to almost polycrystalline state with precipitated Mg, Mn, and MgZn phases. Glass-forming ability of Mg_(65)Zn_(30)Ca_5 alloy is decreased by Mn addition.Results of electrochemical and immersion tests demonstrate that the Mn-doped samples exhibit more negative corrosion potential and larger corrosion current density,suggesting that the corrosion resistance decreases with doping amount of Mn element increasing. 相似文献
8.
Dagadu Joshua C. Li Jian-Ping Aboagye Emelia O. 《Wireless Personal Communications》2019,108(1):591-612
Wireless Personal Communications - We explore the use of two chaotic systems (Bernoulli shift map and Zizag map) coupled with deoxyribonucleic acid coding in an encryption scheme for medical images... 相似文献
9.
A method of spectrometry analysis based on approximation coefficients and deep belief networks was developed. Detection rate and accurate radionuclide identification distance were used to evaluate the performance of the proposed method in identifying radionuclides. Experimental results show that identification performance was not affected by detection time, number of radionuclides, or detection distance when the minimum detectable activity of a single radionuclide was satisfied. Moreover, the proposed method could accurately predict isotopic compositions from the spectra of moving radionuclides. Thus, the designed method can be used for radiation monitoring instruments that identify radionuclides. 相似文献
10.
Regime-based approach recently becomes an important strategy while considering aquatic ecosystems in environmental flow management. The key element for supporting this strategy is long streamflow data which is usually not available for determining natural flow regimes. This study uses a back-propagation network to estimate ungauged natural flow regimes. A set of the upper reaches of Taiwan’s 42 flow stations with non-human control streamflow and at least 20 years daily flow data is used to quantify the natural flow regimes using 31 Indicators of Hydrologic Alteration (IHA). Watershed geomorphologic characteristic factors and rainfall parameters are used to classify homogeneous flow regime areas. The results show that there are three types of flow regimes from the flow stations, and each group of indicators in the IHA has different correlations with different geomorphologic characteristic factors and rainfall parameters. The results of using an artificial neural network model to estimate IHA show that the group average percent error fell from 21 % to 8 % and the average correlation coefficient was over 0.7, indicating that the model presented in this study is able to accurately estimate the natural flow regime in ungauged stations. Instead of predicting daily streamflow, this study estimates indicator values for ease of ecological water resources management. 相似文献