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991.
实体肿瘤微环境一直处于复杂的慢性炎性状态中,其周围充满丰富的炎性介质、炎性细胞,以及调控紊乱的血管系统和蛋白水解酶类。肿瘤相关巨噬细胞(tumor-associated macrophage,TAM)作为肿瘤相关炎症的主要参与者,它在促进肿瘤细胞增殖侵袭和迁移、新生血管形成以及产生免疫抑制等方面的功能对癌症的发生发展产生重要影响。因此针对TAM的深入研究具有重要的科学意义和临床价值,为肿瘤的治疗开辟新的思路和途径。 相似文献
992.
993.
Incipient wetness impregnation method was used to incorporate heteropolyacid H6[PV3Mo9O40]nH2O (HPA) on SiO2 at various HPA loadings (10, 20, 30, 40 wt.% HPA) and calcined temperatures. Catalytic activity of these synthesised catalysts were evaluated through oxidation of 2‐methylcyclohexanone to methyl 6‐oxoheptanoate which was a desired product. In the oxidative conditions the conversion and selectivity of the desired product methyl 6‐oxoheptanoate can reach as high as 97 and 94 wt.%, respectively. The results also suggested that the catalyst with 20 wt.% loading of HPA to be the best one. The catalysts were characterised using a variety of techniques including XRD, BET, FT‐IR and TGA‐DTA. The results indicated that HPA was well dispersed on the SiO2 supporting material. An engine ignition test following ASTM D6890 standard indicated that the oxidative ring‐opening of cyclohydrocarbons can have a positive impact on the cetane numbers and ignition delay time of fuels. © 2012 Canadian Society for Chemical Engineering 相似文献
994.
Hugo Martínez‐Gutiérrez Víctor M. Ovando‐Medina René D. Peralta Eduardo Mendizábal Jorge E. Puig 《Polymer Engineering and Science》2013,53(9):1990-1995
Vinyl acetate (VAc) was polymerized by a seeded semicontinuous heterogeneous process. Stable latexes with a polymer/surfactant weight ratio of 65 were obtained, which is comparable with the highest value reported in the literature for emulsion polymerization but with the advantage of obtaining smaller particles (average diameter, Dp = 53 nm) which are similar to those obtained by microemulsion polymerization. The surfactant (sodium dodecylsulfate, SDS) concentration used in the recipe (0.32 wt%) is much lower than those typically used in microemulsion polymerization. Although molar masses increased during the continuous monomer addition period, they were small at the end of the reaction (Mn = 69 × 103 g·mol–1) and this was attributed to bimolecular termination inside the particles. The values of polymerization rate (Rp) and monomer addition rate (Fm) were nearly the same, indicating that polymerization was performed under monomer starved conditions. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers 相似文献
995.
Jiangang Jia Tieming Guo Shufang Ren Jinjun Lu Qin Ma 《International Journal of Applied Ceramic Technology》2013,10(6):900-907
Phase evolution and morphology of Fe3O4‐Si‐Al powder mixtures during ball milling from 30 min to 20 h were investigated. A 3‐h critical milling was necessary for the occurrence of mechanically activated combustion reaction. The reaction results in the formation of Fe (Si), Fe3Si, and α‐Al2O3. During ball milling from 3 to 20 h, Fe (Si) and Fe3Si were combined into disordered Fe3Si intermetallic and Fe3Si‐Al2O3 composite powder was formed. The presence of in situ formed alumina leads to a decrease in crystallite and particle sizes. The Fe3Si‐Al2O3 particles after milling for 20 h had a crystalline size of 10~12 nm. 相似文献
996.
997.
998.
Dongbin Fan Jianmin Chang Jinsheng Gou Bihua Xia Xueyong Ren 《The Journal of Adhesion》2013,89(8):836-845
Oil-phenol-formaldehyde (Oil-PF) resins containing 50 wt% replacement of petroleum phenol with bio-oil were prepared and different catalysts [sodium carbonate (Na2CO3), urea, and magnesium oxide (MgO)] were added in the synthesis process of resins to accelerate the cure. The cure-acceleration effects of catalysts on cure characteristics of oil-PF resins were investigated by using differential scanning calorimetry (DSC), gel time, and a plywood panels test. The results indicated that catalysts presented different accelerating effects on the cure of the oil-PF resin. Both Na2CO3 and MgO can accelerate the oil-PF resin cure at a low temperature; however, urea seemed to have no significant effect on the cure of the resin. The application of Na2CO3- and MgO-accelerated oil-PF resins reduced hot pressing time for the manufacture of three-layer plywood panels. Compared with MgO, Na2CO3 had more significant accelerating effect on the cure of the oil-PF resin. 相似文献
999.
1000.
Xiao‐Min Qian Zhen‐Dong Shi Yu Ren Chao‐Yong Liu Ya‐Ru Ji Li‐Xia Long Peiyu Pu Jing Sheng Xu‐Bo Yuan Chun‐Sheng Kang 《应用聚合物科学杂志》2013,127(1):570-576
Temozolomide (TMZ) is a promising chemotherapeutic agent for treating glioblastomas. However, resistance develops quickly and with a high frequency. Efforts to overcome chemoresistance are, therefore, critically needed. In present study, a poly(amidoamine; PAMAM) dendrimer was used as a vector to deliver microRNA‐21 inhibitor (miR‐21i) into U87 cells and the chemosensitivity of the combination effect of miR‐21i and TMZ for glioma therapy was investigated. Flow cytometry analysis showed the uptake efficiency of microRNA‐21 inhibitor after complexation with PAMAM. Real‐time PCR and in situ hybridization indicated that, compared with TMZ or miR‐21i treated cells, cells simultaneously treated with miR‐21i and TMZ showed a remarkable decrease in the microRNA‐21 (miR‐21) level. The transfection of miR‐21i enhanced the chemosensitivity by significantly decreasing the IC50 value of TMZ to glioma cells. Knockdown of miR‐21 promoted the cells' apoptosis, and at the same time, inhibited cell invasion. In conclusion, the combination treatment of glioma cells with TMZ and miR‐21i could yield a synergistic effect in inhibition of human glioma cell line. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献