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141.
Atherosclerosis (AS) is one of the leading causes of death among the elderly, and is primarily caused by foam cell generation and macrophage inflammation. Rutin is an anti-inflammatory, anti-oxidant, anti-allergic, and antiviral flavonoid molecule, known to have anti-atherosclerotic and autophagy-inducing properties, but its biological mechanism remains poorly understood. In this study, we uncovered that rutin could suppress the generation of inflammatory factors and reactive oxygen species (ROS) in ox-LDL-induced M2 macrophages and enhance their polarization. Moreover, rutin could decrease foam cell production, as shown by oil red O staining. In addition, rutin could increase the number of autophagosomes and the LC3II/I ratio, while lowering p62 expression. Furthermore, rutin could significantly inhibit the PI3K/ATK signaling pathway. In summary, rutin inhibits ox-LDL-mediated macrophage inflammation and foam cell formation by inducing autophagy and modulating PI3K/ATK signaling, showing potential in treating atherosclerosis.  相似文献   
142.
We systematically measure the superconducting(SC) and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c~3.5 K.We find that the upper critical field H_(c2)(T) exhibits a large anisotropic ratio of H_(c2)~(ab)/H_(c2)~c~9 at zero temperature and fitting its temperature dependence requires a minimum two-band effective model.Moreover,the ratio of the lower critical field,H_(c1)~(ab)/H_(c1)~c,is also found to be larger than 1,which indicates that the in-plane energy dispersion is strongly renormalized near Fermi energy.Both H_(c1)(T) and SC diamagnetic signal are found to change little initially below T_c~3.5 K and then to increase abruptly upon cooling to a characteristic temperature of ~2.8 K.Furthermore,we identify a two-fold anisotropy of in-plane angular-dependent magnetoresistance in the mixed state.Interestingly,we find that,below the same characteristic T~2.8 K,the orientation of this two-fold anisotropy displays a peculiar twist by an angle of 60° characteristic of the Kagome geometry.Our results suggest an intriguing superconducting state emerging in the complex environment of Kagome lattice,which,at least,is partially driven by electron-electron correlation.  相似文献   
143.
The bioactive compound shikonin was successfully isolated and purified from the crude extract of the traditional Chinese medicinal plant Lithospermum erythrorhizon Sieb. et Zucc. by preparative high-speed counter-current chromatography (HSCCC). The preparative HSCCC was performed using a two-phase solvent system composed of n-hexane-ethylacetate-ethanol-water (16:14:14:5 (v/v)). A total amount of 19.6 mg of shikonin at 98.9% purity was obtained from 52 mg of the crude extract (containing 38.9% shikonin) with 96.9% recovery. The preparative isolation and purification of shikonin by HSCCC was completed in 200 min in a one-step separation.  相似文献   
144.
研究了Co(Ⅱ)、Ni(Ⅱ)-NH3-XO混配络合物和Co(Ⅱ)、Ni(Ⅱ)-NH3-XO-CTMAB多元络合物的形成条件及吸收光谱特性,结果表明,在pH 9.5的氨性缓冲溶液中,[NH3]/[XO]值在100~400范围内所形成的钴、镍多元络合物的最大吸收波长分别为530和590 nm,钴的多元络合物在0~2.0 mg.L-1、镍的多元络合物在0~2.6 mg.L-1范围内符合比耳定律,相对标准偏差分别为2.1%和1.9%。  相似文献   
145.
Three tetraorganodistannoxanes containing silicon were synthesized and their catalytic properties in esterification and acetalization were observed via the reactions of acetic acid with isoamyl alcohol and butyraldehyde with glycol. The factors affecting the reaction, such as the catalyst dosage, reaction time and solvent, etc. were discussed. The results show that the three tetraorganodistannoxanes displayed similar good catalytic activities compared to dichlorotetrabutyldistannoxane in esterification and acetalization. When the dosage of [ClBu2SnOSn-(CH2SiMe3)2Cl]2 was 1.5% based on the mass of reactant, the yield of isoamyl acetate was 91.8% and the yield of butyraldehyde glycol acetal 94.2%. The different alkyl and bridging groups on Sn sites in the structure of tetraorganodistannoxanes showed some influence on the catalytic activities of these compounds. __________ Translated from Chinese Journal of Applied Chemistry, 2007, 24 (11): 1265–1272  相似文献   
146.
A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymerized on the surface of macroporous acrylate adsorbent spheres. The template BSA was removed by treatment with 2.00 mol L-1 potassium chloride (KCl) solution and the adsorbed proteins were detected with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 0.150, 0.500, and 2.00 mo...  相似文献   
147.
Graphene nanosheets (GNSs) loading graphene-encapsulated iron microspheres (GEIMs) were fabricated by heat treatment of graphene oxide nanosheets (GONs) with ferric trichloride (FeCl(3)). The special pentagon-hexagonal graphene shells have been produced by precipitation of carbon from metal carbide solutions, thanks to the high reactivity of GONs and ferric nanoparticles dispersing homogeneously between graphene layers. The morphology, structure and elemental composition of GEIMs were investigated by scanning electron microscope, X-ray diffraction and electron energy disperse spectroscope, respectively. The formation mechanism of GEIMs was proposed. Hollow graphene microspheres (HGMs) on the GNSs were obtained with the removal of ferric species in GEIMs. When used as the anode materials for lithium-ion batteries, the almost graphitic HGMs exhibit stable voltage platform at ca. 0.2 V, excellent cycle capability and higher reversible capacity of about 440 mAh g(-1) after 50 cycles and possess great potential application in lithium-ion batteries.  相似文献   
148.

Background  

The virtual screening (VS) of lead compounds using molecular docking and pharmacophore detection is now an important tool in drug discovery. VS tasks typically require a combination of several software tools and a molecular graphics system. Thus, the integration of all the requisite tools in a single operating environment could reduce the complexity of running VS experiments. However, only a few freely available integrated software platforms have been developed.  相似文献   
149.
Pretty porous POMs: Ionothermal synthesis was applied to prepare porous POM-based open frameworks. The structural integrity remains unchanged until 300?°C; most importantly, the bulky tetrabutylammonium cations within their nanosized channels can be replaced by transition-metal ions through a cation-exchange process, and subsequent gas adsorption measurements confirm their permanent porosity.  相似文献   
150.
建立了高碘酸氧化法快速测定进口粗甘油中甘油含量的分析方法。对高碘酸钠加入量、溶液pH值和放置时间等主要影响因素进行了考察。经试验确定了最佳实验条件:质量浓度为60 g/L的高碘酸钠溶液加入量35mL,pH值在0.4~1.6之间,放置时间40 min。在选定实验条件下,该方法测定结果的相对标准偏差为1.26%(n=7),加标回收率为97.2%~104.1%。  相似文献   
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