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排序方式: 共有60条查询结果,搜索用时 15 毫秒
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Jing Zhang Yaling Tan Guorong Li Lexian Chen Minyi Nie Zhaohua Wang Hong Ji 《Molecules (Basel, Switzerland)》2021,26(4)
Coumarins possesses immeasurable antitumor potential with minimum side effects depending on the substitutions on the basic nucleus, which exhibits great prospects for antitumor drug development. In an attempt to develop novel antitumor candidates, a series of coumarin sulfonamides and amides derivatives were designed and synthetized. The majority of these derivatives showed good cytotoxic activity against MDA-MB-231 and KB cell lines, among which compound 9c was the most potent against MDA-MB-231 cells, with IC50 value of 9.33 μM, comparable to 5-fluorouracil. Further investigation revealed that compound 9c had versatile properties against tumors, including inhibition of cell migration and invasion as well as inducing apoptosis. Reactive oxygen species (ROS) assay and western blotting analysis suggested that compound 9c promoted cancer cell apoptosis by increasing ROS levels and upregulating the expression of caspase-3 in MDA-MB-231 cells. These results indicated that compound 9c could be promising lead compound for further antitumor drug research. 相似文献
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单丁基磷酸酯的合成与表征 总被引:1,自引:0,他引:1
本文报道用三氯氧磷酯化、水解方法制备单丁基磷酸酯,用红外、核磁共振,质谱等方法对其结构进行了分析与表征。 相似文献
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Hai Wang Yong Liu Minyi Zhong Hongmei Xu Hong Huang Hui Shen 《Journal of nanoparticle research》2011,13(5):1855-1863
Various TiO2 nanomaterials, such as nanosheets, nanoflowers, and nanowires were directly self assembled on titanium substrate on a large
scale under hydrothermal conditions. The morphology of the formed TiO2 nanomaterials could be easily tuned by varying the experimental parameters of temperature, reaction time, and the NaOH concentration.
A possible formation mechanism was suggested on the basis of the shape evolution of TiO2 nanostructures by SEM images in combination with XRD patterns of as-grown samples. The optical properties of TiO2 nanosheets, nanoflowers, and nanowires were characterized by reflectance spectroscopy. The studies revealed that the absorption
capability of visible light is obviously different for TiO2 with different morphologies. Moreover, TiO2 nanosheets exhibited better light trapping than TiO2 nanoflowers and TiO2 nanowires due to their unique nanostructure. 相似文献
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设J={J1,…,Jn}是n个工件的集合,M是一台机器.每个工件Ji要在机器M上加工一次,而且是相继只加工一次,即加工不能够中断.Ji的加工时间是pi,准备时间是ri,即Ji不能在ri之前加工,要求完工的期限是di,即工件Ji的加工应该在di之前完成.否则,这个工件将被拒绝放在一旁.我们的目的是寻找排序算法A,当使用到给定的J上时,使被拒绝的工件个数为最少.
1978年Kise,Ibaraki,Mine等在条件ri〈rj蕴涵di≤dj(对于任何1≤i,j≤n)下,对于任何给定的J找到算法A他们在论文[1]中“证明”算法A是最优算法.最近,李杉林给出一个例子说明他们的证明中的一个关键引理是错误的.本文作者在书[2]中也沿用了这个错误的“证明”.对于算法A的最优性,本文给出一个新的简单的证明. 相似文献
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Yue Zhang Jing Liu Longchuan Li Minyi Du Wenxue Fang Dongxin Wang Xuexiang Jiang Xiaoping Hu Jue Zhang Xiaoying Wang Jing Fang 《Magnetic resonance imaging》2014
Understanding the effect of postherpetic neuralgia (PHN) pain on brain activity is important for clinical strategies. This is the first study, to our knowledge, to relate PHN pain to small-world properties of brain functional networks. Functional magnetic resonance imaging (fMRI) was used to construct functional brain networks of the subjects during the resting state. Sixteen patients with PHN pain and 16 (8 males, 8 females for both groups) age-matched controls were studied. The PHN patients exhibited decreased local efficiency along with non-significant changes of global efficiency in comparison with the healthy controls. Moreover, regional nodal efficiency was found to be significantly affected by PHN pain in the areas related to sense (postcentral gyrus, inferior parietal gyrus and thalamus), memory/affective processes (parahippocampal gyrus) and emotional activities (putamen). Significant correlation (p < 0.05) was also found between the nodal efficiency of putamen and pain intensity in PHN patients. Our results suggest that PHN modulates the local efficiency, and the small-world properties of brain networks may have potentials to objectively evaluate pain information in clinic. 相似文献
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Haiwu Yang Minyi Liang Fang Tian 《Acta Crystallographica. Section C, Structural Chemistry》2024,80(3):62-65
A salt of vandetanib, namely, 4-({4-[(4-bromo-2-fluorophenyl)amino]-6-methoxyquinazolin-7-yl}methoxy)-1-methylpiperazin-1-ium 2-(butylamino)-4-phenoxy-6-sulfamoylbenzoate acetonitrile monosolvate, C22H25BrFN4O2+·C17H19N2O5S−·C2H3N, composed of kinase inhibitor vandetanib and sulfamyl diuretic bumetanide in a 1:1 molar ratio, is reported. There is proton transfer between the piperidine ring of vandetanib and the carboxyl group of bumetanide to form the salt. In the vandetanib cation, the arene and pyrimidine rings are not coplanar, their planes subtending a dihedral angle of 60.47 (14)°. The roles of the intermolecular interactions in the crystal packing were clarified using Hirshfeld surface analysis, and two-dimensional fingerprint plots indicate that the most important contributions to the crystal packing are from H…H (40.5%), O…H/H…C (20.7%), C…H/ H…C (18.8%) and N…C/C…N (9.0%) contacts. 相似文献
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Hai Wang Yong Liu Hong Huang Minyi Zhong Hui Shen Yuanhao Wang Hongxing Yang 《Applied Surface Science》2009,255(22):9020-9025
Low resistance dye-sensitized solar cells (DSSCs) based on all-titanium substrates were proposed in this paper. To minimize the internal resistance of DSSCs, the titanium wires and titanium sheets were used as the substrates of the photoanode and the counter electrode, respectively. Compared with the FTO substrate, titanium wires could absorb much diffused light by back reflection since the reflectivity in the titanium sheet was highly increased up to 53.12%. Furthermore, the transmittance of the front cover was increased by 13.2% using the super white glass instead of FTO substrate. The thickness of TiO2 thin film coated on titanium wire was optimized to achieve a high cell performance. The efficiency of 5.6% for the cell was obtained with a Jsc of 15.41 mA cm−2, Voc of 0.59 V, and FF of 0.62. The results showed that the titanium-based DSSCs had superiority for producing the large-scale DSSCs without metal grid line. 相似文献