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171.
ERCC1 is a DNA repair gene and has been associated with resistance to DNA damaging agents. In this study we hypothesized that a polymorphism of ERCC1 Asn118Asn (C -> T) might affect the platinum-resistance of epithelial ovarian cancer patients to platinum-taxane chemotherapy administered postoperatively. Using the SNapShot assay, we assessed this polymorphism in ERCC1 in 60 ovarian cancer patients. Platinum-resistance was defined as progression on platinum-based chemotherapy or recurrence within 6 months of completing therapy. Although not significant, platinum-resistance was less frequently observed in patients with the C/T+T/T genotype (P=0.064). Multivariate analysis showed that the C/T+T/T genotypes constituted an independent predictive factor of reduced risk of platinum-resistance in ovarian cancer (odds ratio 0.17, 95% confidence interval 0.04-0.74, P=0.018, Fisher's exact test). No significant correlation was observed between overall survival and the ERCC1 polymorphism. Our results suggest that genotyping of the ERCC1 polymorphism Asn118Asn may be useful for predicting the platinum-resistance of epithelial ovarian cancer patients. However, these findings require prospective confirmation.  相似文献   
172.
Jang TS  Ku IW  Jang MS  Keum G  Kang SB  Chung BY  Kim Y 《Organic letters》2006,8(2):195-198
[reaction: see text] A new and efficient indium-mediated one-pot three-component reaction for the synthesis of N-aryl-substituted homoallylamines from aromatic amines, enol ethers, and allylic bromides in THF at room temperature is described.  相似文献   
173.
We used molecular dynamics (MD) simulations to investigate the structures and properties of Newton black films (NBF) for several surfactants: sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (C16TAB), and surfactin using film thicknesses up to 10 nm. By calculating the interface formation energy for various packing conditions on the surface pressure-area isotherm, we found that the most probable surface concentration is approximately 42 A(2)/molecule for SDS and C16TAB and approximately 170 A(2)/molecule for surfactin. We then used this most probable concentration of each surfactant to simulate NBF with various film thicknesses. From analyzing the disjoining pressure-film thickness isotherms with the density profiles and the solvation coordination number, we found that the increase of the disjoining pressure during the film thinning was coupled with the change in inner structure of the NBF (i.e., density profile and the solvation of ionic entities). In the range of film thicknesses less than approximately 30 A, the disjoining pressures for the SDS and C16TAB were found to be larger than that of the surfactin. We predicted the Gibbs elasticity (175 dyn/cm for surfactin; 109 dyn/cm for C16TAB; 38 dyn/cm for SDS) required to assess the stability of NBF against surface concentration fluctuations, and the shear modulus (6.5 GPa for the surfactin; 6.1 GPa for the C16TAB; 3.5 GPa for the SDS) and the yield stress (approximately 0.8 GPa for surfactin; approximately 0.8 GPa for C16TAB; approximately 0.4 GPa for the SDS) to assess the mechanical stability against the externally imposed mechanical perturbation.  相似文献   
174.
Wei Jie Ong  Eng Soon Tok 《Surface science》2012,606(13-14):1037-1044
Using Scanning Tunneling Microscope (STM), we show that the surface undergoes phase transformation from disordered “1 × 1” to (7 × 7) reconstruction which is mediated by the formation of Si magic clusters. Mono-disperse Si magic clusters of size ~ 13.5 ± 0.5 Å can be formed by heating the Si(111) surface to 1200 °C and quenching it to room temperature at cooling rates of at least 100 °C/min. The structure consists of 3 tetra-clusters of size ~ 4.5 ? similar to the Si magic clusters that were formed from Si adatoms deposited by Si solid source on Si(111)-(7 × 7) [1]. Using real time STM scanning to probe the surface at ~ 400 °C, we show that Si magic clusters pop up from the (1 × 1) surface and form spontaneously during the phase transformation. This is attributed to the difference in atomic density between “disordered 1 × 1” and (7 × 7) surface structures which lead to the release of excess Si atoms onto the surface as magic clusters.  相似文献   
175.
The adsorption of S2 on the Si(1 1 1)-(7 × 7) surface and the interaction of copper and sulfur on this sulfur-terminated Si(1 1 1) surface have been studied using synchrotron irradiation photoemission spectroscopy and scanning tunneling microscopy. The adsorption of S2 at room temperature results in the passivation of silicon dangling bonds of Si(1 1 1)-(7 × 7) surface. Excessive sulfur forms Sn species on the surface. Copper atoms deposited at room temperature directly interact with S-adatoms through the formations of Cu-S bonds. Upon annealing the sample at 300 °C, CuSx nanocrystals were produced on the sulfur-terminated Si(1 1 1) surface.  相似文献   
176.
In the process of measurements such as optical interferometry and fringe projection, an important stage is fringe pattern analysis. Many advanced fringe analysis algorithms have been proposed including regularized phase tracking (RPT), partial differential equation based methods, wavelet transform, Wigner–Ville distribution, and windowed Fourier transform. However, most of those algorithms are computationally expensive. MATLAB® is a general algorithm development environment with powerful image processing and other supporting toolboxes. It is also commonly used in photomechanical data analysis. With rapid development of multicore CPU technique, using multicore computer and MATLAB® is an intuitive and simple way to speed up the algorithms for fringe pattern analysis. The paper introduces two acceleration approaches for fringe pattern processing. The first approach is task parallelism using multicore computer and MATLAB® parallel computing toolbox. Since some algorithms are embarrassing problems, our first approach makes use of this characteristic to parallelize these algorithms. For this approach, parallelized windowed Fourier filtering (WFF) algorithm serves as an example to show how parallel computing toolbox accelerates the algorithm. Second, data parallelism using multicore computer and MATLAB® parallel computing toolbox is proposed. A high level parallel wrapping structure is designed, which can be used for speeding up any local processing algorithms. WFF, windowed Fourier ridges (WFR), and median filter are used as examples to illustrate the speedup. At last, the results show that the parallel versions of former sequential algorithm with simple modifications achieve the speedup up to 6.6 times.  相似文献   
177.
We report on the aerosol synthesis and optical characterization of ZnO/unoxidized graphene (UG) platelets nanocomposite films with high optical transparency (>85% at visible wavelengths). The ZnO/UG composite films, in which UG nanoplatelets are embedded in nano‐grained ZnO, were fabricated from colloidal suspensions of UG platelets with an aqueous zinc precursor. From photoluminescence (PL) spectra of the UG composite films, it was found that PL intensity decreases with the addition of UG platelets. The features of PL intensity in the UG composites are in contrast to that of ZnO/graphene oxide (G‐O) platelets composites, and can be explained by the absence of an oxygen vacancy filling effect, due to the unoxidized nature of UG and an increase in defect sites in its composites. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
178.
Conductivity stability at thermal environment of conductive polyaniline‐complexes/polyimide (PANI‐complexes/PI) blends, which were doped by camphorsulfonic acid (CSA) and dodecylbenzenesulfonic acid (DBSA), respectively, were investigated by conductivity measurements, electron spin resonance (ESR) spectra, differential and scanning thermometer (DSC). In the conversion process of PANI/Polyamic acid (PAA) to PANI/PI, the blend endeavored some kinds of alteration such as decomplexation of moisture and solvent, dissociation of dopant, crosslinking of PANI chain, and the imidization of PAA chain. PANI‐DBSA/PI showed higher thermal stability of conductivity than PANI‐CSA/PI, and both samples showed nearly linear decay of conductivity with increasing temperature showing greatly enhancement of conductivity stability. When they were exposed at near or over glass transition temperature, the conductivity decay became faster. The conductivity stability at base environment was also higher for PANI‐DBSA/PI due to difficulty in accessing of hydroxyl ion to PANI, which were resulted from dopant. DBSA‐doped blends showed increased polaron mobility and concentration at relatively high temperature, which led to extremely higher conductivity and its stability at high temperature. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
179.
Functional monomers containing a rosin moiety, maleopimaric acid anhydride (MPA) and fumaropimaric acid (FPA) were synthesized from gum rosin. Monofunctional acrylic rosin derivatives were synthesized from esterification of MPA and various acrylates, (2-hydroxyethyl acrylate) (HEA), 3-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate. Monofunctional monomers were copolymerized with (methyl methacrylate) (MMA) by radical polymerization. Trifunctional acrylate was synthesized from FPA and HEA. All the monomers and polymers showed good solubility and low absorbance in the UV region (200-400 nm). Negative patterns from rosin derivatives were obtained by two methods, one is a photocuring method using trifunctional acrylate and copolymers, and the other is photocrosslinking of copolymers using a photocrosslinker under UV (I-line) radiation. Negative photoresists containing rosin moiety showed high contrast and minimum linewidth of 2.2 μm.  相似文献   
180.
A series of three thiophene–naphthalene‐based asymmetric oligomers—5‐decyl‐2,2′:5′,2′′:5′′,2′′′‐quaterthiophene (DtT), 5‐decyl‐5′′‐(naphthalen‐2‐yl)‐2,2′:5′,2′′‐terthiophene (D3TN), and 5‐(4‐decylphenyl)‐5′‐(naphthalen‐2‐yl)‐2,2′‐bithiophene (DP2TN)—was synthesized by Suzuki cross‐coupling reactions. The long alkyl side chains improved both the solubility of the oligomers in solvents and their tendency to self‐assemble. UV/Vis absorption measurements suggested that DtT, D3TN, and DP2TN form H‐type aggregates with a face‐to‐face packing structure. In addition, the three oligomers were found to adopt vertically aligned crystalline structures in films deposited on substrates, as revealed by grazing‐incidence wide‐angle X‐ray scattering. These oligomers were used as the active layers of p‐type organic field‐effect transistors, and the resulting devices showed field‐effect mobilities of 3.3×10?3 cm2 V?1 s?1 for DtT, 1.6×10?2 cm2 V?1 s?1 for D3TN, and 3.7×10?2 cm2 V?1 s?1 for DP2TN. The differences in transistor performances were attributed to the degree of π overlap and the morphological differences determined by the molecular structures.  相似文献   
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