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1.
Lipotoxicity is defined as deposition of excess fat associated with an inflammatory response. Metabolomic analysis of fatty acids (FAs) can be a marker of silent inflammation. ω3-Enriched diet, celecoxib, and safranal may have a protective anti-inflammatory role. In this work, total FAs extracted from red blood cells and arachidonic acid-to-eicosapentaenoic acid (AA-to-EPA) ratios were assessed using GC–MS assay in single-ion monitoring mode. The study was conducted on 64 male rats divided into eight groups: I, controls; II, rats received high-fat diet (HFD), III, rats received ω-6-enriched HFD; IV, rats received ω-3-enriched HFD; V, rats received celecoxib with HFD; VI, rats received safranal with HFD; VII and VIII, rats received celecoxib and safranal with ω-3 HFD, respectively. GC–MS Gas chromatography Mass spectrometry was performed for analysis of fatty acid methyl ester. Enzyme-linked immunosorbent assay was used to analyze serum interleukin-6 (IL-6) and transforming growth factor-beta 1 (TGF-β1) concentrations. A statistically significant decrease of AA-to-EPA ratio was observed in group VII when compared with the groups receiving HFDs. This group also showed the lowest serum IL-6 level and highest TGF-β1 level. In conclusion, ω3-enriched diet along with drugs (e.g. celecoxib) and herbal medications (e.g. safranal) may have an anti-inflammatory effect in lipotoxicity. GC–MS with single-ion monitoring is valid for the analysis of FAs.  相似文献   
2.
The effect of adding alkali salts to protein samples for capillary electrophoretic (CE) analysis of intact proteins was studied. A high degree of peak stacking, even for large proteins, was found to occur when alkali salts were added to the sample. The addition of salt to the protein sample promotes a strong improvement in the peak efficiency of individual proteins giving up to 2.1 × 106 apparent plates/m. The concentration of salt required in the sample to reach optimal peak efficiency show dependency on both the molecular weight and molar concentration of the protein. However, adding salt will, at a sufficiently high concentration, cause a mixture of proteins to co-migrate to one very sharp peak. The observed sample stacking effect was obtained with a number of different surface modified silica capillaries indicating a general phenomenon and not surface coating specific.  相似文献   
3.
The propagation of linear and nonlinear electrostatic waves is investigated in a magnetized anisotropic electron-positron-ion (e-p-i) plasma with superthermal electrons and positrons. A two-dimensional plasma geometry is assumed. The ions are assumed to be warm and anisotropic due to an external magnetic field. The anisotropic ion pressure is defined using the double adiabatic Chew-Golberger-Low (CGL) theory. In the linear regime, two normal modes are predicted, whose characteristics are investigated parametrically, focusing on the effect of superthermality of electrons and positrons, ion pressure anisotropy, positron concentration and magnetic field strength. A Zakharov-Kuznetsov (ZK) type equation is derived for the electrostatic potential (disturbance) via a reductive perturbation method. The parametric role of superthermality, positron content, ion pressure anisotropy and magnetic field strength on the characteristics of solitary wave structures is investigated. Following Allen and Rowlands [J. Plasma Phys. 53, 63 (1995)], we have shown that the pulse soliton solution of the ZK equation is unstable to oblique perturbations, and have analytically traced the dependence of the instability growth rate on superthermality and ion pressure anisotropy.  相似文献   
4.
LetB 1 be a ball of radiusr 1 inS n (ℍn), and letB 0 be a smaller ball of radiusr 0 such thatB 0 B 1 . ForS n we considerr 1 π. Let u be a solution of the problem- δm = 1 in Ω :=B 1 /B 0 vanishing on the boundary. It is shown that the associated functionalJ (Ω) is minimal if and only if the balls are concentric. It is also shown that the first Dirichlet eigenvalue of the Laplacian on Ω is maximal if and only if the balls are concentric.  相似文献   
5.
Perception of a target voice in the presence of a competing talker, of same or different gender as the target, was investigated in cochlear implant users, in implant-alone and bimodal (acoustic hearing in the non-implanted ear) conditions. Recordings of two male and two female talkers acted as targets and maskers, to investigate whether bimodal benefit increased for different compared to same gender target/maskers due to increased ability to perceive and utilize fundamental frequency and spectral-shape differences. In both listening conditions participants showed benefit of target/masker gender difference. There was an overall bimodal benefit, which was independent of target/masker gender difference.  相似文献   
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7.
Palpation is an economical, safe and effective method to detect breast cancer among other expensive and sometimes limited diagnostic tools such as mammography and magnetic resonance imaging (MRI). To understand the mechanics of palpation, a rigid inclusion was embedded in a phantom gel to simulate the lesion. An array of indents using a rigid indenter was made over an assigned area of the phantom surface, while the applied load, F, was measured as a function of instantaneous indentation depth, w. When the local stress field interacted with a sufficiently shallow inclusion, the mechanical response F(w) yielded an augmented apparent stiffness C. A 2-dimensional spatial map of C shows the presence, depth, and geometry of the simulated lesion. A camcorder was used to capture the in-situ movement of the inclusion during indentation, which showed consistency with the finite element (FEA) prediction. Results provide preliminary confirmation that mechanical indentation is a good tool to complement existing imaging techniques and has the potential to guide design and fabrication of an automatic palpation device.  相似文献   
8.
Elhamili A  Bergquist J 《Electrophoresis》2011,32(13):1778-1785
In this study, the extraction recoveries of an anticancer drug (Imatinib) from human plasma using a common liquid-liquid extraction (LLE) method and a new strong cation exchange (SCX) solid-phase extraction (SPE) column was investigated. The extracts were analyzed with CE coupled on-line to electrospray ionization (ESI) time-of-flight mass spectrometry (TOF-MS) using a monoquaternarized piperazine compound (M7C4I) for capillary coatings. Clean extracts with high and reproducible extraction recoveries ranging between 85 and 91% with % RSD values of 2.5% (n = 3) were obtained using the SCX-SPE columns. This can be compared with the recoveries obtained with the LLE method ranging between 30 and 35%. The CE-ESI-TOF-MS analysis was performed in <10 min with peak efficiencies up to 4.7 × 10? plates/m and an average % RSD for the repeatability of the migration times of the analytes of 1.9% (n = 3) using acidic buffer and adding 5% ACN to the sample. The calibration curves were linear over the range of 0-1500 ng/mL with correlation coefficient (R2 ≥ 0.997 and % RSD values of 0.5% (n=3). The intra-day and inter-day assay variations were lower than 8%. The presented CE-ESI-TOF-MS method with the use of SCX-SPE columns yielded rapid, efficient and high extraction recoveries together with high sensitivity (LOD 5 ng/mL), selectivity and good linearity. Accordingly, the method can readily be used for accurate determination and therapeutic monitoring of the Imatinib blood levels for more effective patient treatment. In addition, it can be applied for the extraction, quantification and clinical assessments of metabolites of Imatinib and other basic pharmaceutical drug molecules in biological fluids or pharmaceutical dosage forms.  相似文献   
9.
Using kinetic theory approach, the dispersion relation ωr and Landau damping rate γ for dust ion acoustic waves are investigated numerically and analytically in an unmagnetized collisionless dusty plasma considering Cairns distribution for electrons and ions in stationary dust particles background. The phase velocity and Landau damping rate are calculated in the limits vtd∥ < vti∥ << ω/k << vte∥ . The electrons and ions non-thermality effects are incorporated via the non-thermality parameter (0 ≤ α < 1) . The real frequency ωr and Landau damping rate γ of the mode in Cairns bi-Maxwellian distributed plasma are graphically shown to depend on plasma parameters namely non-thermality index α , ion to electron temperature ratio Ti∥/Te∥ and the dust concentration parameter δ (=1 − ηZd) .  相似文献   
10.
Let B 1 be a ball in a non-compact rank-one symmetric space and let B 0 be a smaller ball inside it. It is shown that if y is the solution of the problem ?Δu = 1 in ${B_1 \setminus \bar{B_0}}$ vanishing on the boundary, then the Dirichlet-energy of y is minimal if and only if the balls are concentric. It is also shown that the first Dirichlet eigenvalue of the Laplacian on ${B_1 \setminus \bar{B_0}}$ is maximal if and only if the two balls are concentric. The formalism of Damek-Ricci harmonic spaces is used.  相似文献   
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