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81.
The azido sugar,GalNAz,was successfully used for imaging and perturbing protein glycosylation in triple-negative breast cancer cell line,MDA-MB-231.After the incorporation of GalNAz in the triple-negative breast cancer cell line,the tumorigenicity of these cells was decreased.Results from gene analysis and drug treatment suggest that the tumorigenicity decrease may be attributed to the reduction of cancer stem cell population.Possible mechanisms of GalNAz induced cancer stem cells(CSCs) proportion change are discussed.  相似文献   
82.
E. Daloia  G. Lim  J. Melton  J. Roubie 《合成通讯》2013,43(18):2617-2622
Successive treatment of (Z)-(2-aminothiazol-4-yl) -2-methoxyiminoacetic acid, 1, with 0.9 to 1.0 equiv. of hydrogen chloride and 1.04 equiv. (chloromethylene) dimethylammonium chloride provides (Z) - (2-aminothiazol-4-yl) -2-methoxyiminoacetyl-chloride hydrochloride, 3, in high yield.  相似文献   
83.
84.
Despite its cultural and nutritional importance for local Aboriginal people, the unusual insect honey produced by Western Australian honeypot ant (Camponotus inflatus) has to date been rarely investigated. This study reports on the honey’s physicochemical properties, its total phenolic, major sugars and 5-hydroxymethylfurfural contents, and its antioxidant activities. The honey’s color value is 467.63 mAU/63.39 mm Pfund, it has a pH of 3.85, and its electric conductivity is 449.71 µSiemens/cm. Its Brix value is 67.00, corresponding to a 33% moisture content. The total phenolics content is 19.62 mg gallic acid equivalent/100 g honey. Its antioxidant activity measured using the DPPH* (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing–antioxidant power) assays is 1367.67 µmol Trolox/kg and 3.52 mmol Fe+2/kg honey, respectively. Major sugars in the honey are glucose and fructose, with a fructose-to-glucose ratio of 0.85. Additionally, unidentified sugar was found in minor quantities.  相似文献   
85.
A colloidal suspension of exfoliated, layered cobalt oxide nanosheets has been synthesized through the intercalation of quaternary tetramethylammonium ions into protonated lithium cobalt oxide. According to atomic force microscopy, exfoliated nanosheets of layered cobalt oxide show a plateau‐like height profile with nanometer‐level height, underscoring the formation of unilamellar 2D nanosheets. The exfoliation of layered cobalt oxide was cross‐confirmed by X‐ray diffraction, UV/Vis spectroscopy, and transmission electron microscopy. The maintenance of the hexagonal in‐plane structure of the cobalt oxide lattice after the exfoliation process was evidenced by selected‐area electron diffraction and Co K‐edge X‐ray absorption near‐edge structure analysis. The zeta‐potential measurements clearly demonstrated the negative surface charge of cobalt oxide nanosheets. Adopting the nanosheets of layered cobalt oxide as a precursor, we were able to prepare the monodisperse CoO nanocrystals with a particle size of ≈10 nm as well as the heterolayered film composed of cobalt oxide monolayer and polycation.  相似文献   
86.
We describe herein the synthesis of metallic copper nanoparticles in the presence of poly(vinylpyrrolidone), employed as a protecting agent, via a polyol method in ambient atmosphere. The obtained copper particles were confirmed by XRD to be crystalline copper with a face-centered cubic (fcc) structure. We observed monodisperse spherical copper nanoparticles with a diameter range 45+/-8 nm. The particle size and its distribution are controlled by varying the synthesis parameters such as the reducing agent concentration, reaction temperature, and precursor injection rate. The precursor injection rate plays an important role in controlling the size of the copper nanoparticles. On the basis of XPS and HRTEM results, we demonstrate that the surface of the copper is surrounded by amorphous CuO and that poly(vinylpyrrolidone) is chemisorbed on the copper surface.  相似文献   
87.
The charged-particle multiplicity distribution and forward-backward correlation ofe + e ? annihilation at 29 GeV are discussed on the basis of a mixed two-component model.  相似文献   
88.
The purpose of this paper is to describe the structures of the Möbius semigroup induced by the Möbius transformation group (?, SL(2,?)). In particular, we study stabilizer subsemigoups of Möbius semigroup via the triangle semigroup. In this work, we obtained a geometric interpretation of the least contraction coefficient function of the Möbius semigroup via the triangle semigroup and investigated an extension of stabilizer subsemigoups of the Möbius semigroup. Finally, we obtained a factorization of our stabilizer subsemigoups of the Möbius semigroup.  相似文献   
89.
Relationship among interatomic potential functions can be useful in shedding insight on the extent of similarity, and in obtaining a potential function from parameters of another potential function. The 2-body portion of the Biswas-Hamann (BH) and the Kaxiras-Pandey (KP) potential functions are related by equating both functions, as well as their corresponding derivatives up to the third order at the equilibrium bond length. Validity of the parametric relationship is verified by plotting the loose form of the 2-body BH potential in terms of KP parameters and comparing it with the KP potential function. The parametric relationships developed herein are then compared with those that concern other potential functions, with particular emphasis on the scaling factors.  相似文献   
90.
Investigations were carried out for laser-effected darkening and damage-free laser marking on thermoplastic elastomers (TPEs). Titanium dioxide (TiO2) was studied as the laser-sensitive additive to the TPEs for its role in enhancing laser marking contrast and its effect on the TPE properties. Laser beam characteristics, processing variables and percentage loading of TiO2 in the TPEs were found to have significant effect on the marking contrast. Surface damage-free and high contrast marking have been achieved with short pulse UV lasers. The laser-effected darkening was found to penetrate into the material in the order of a few tens of microns. XPS analysis was carried out to understand the laser-effected darkening mechanism. Potential applications of the technique are highlighted.  相似文献   
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