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201.
This study was conducted to determine the potential interaction of aged garlic extract (AGE) with carvedilol (CAR), as well as to investigate the role of S-allyl-l-cysteine (SAC), an active constituent of AGE, in rats with isoproterenol (ISO)-induced myocardial dysfunction. At the end of three weeks of treatment with AGE (2 and 5 mL/kg) or SAC (13.1 and 32.76 mg/kg), either alone or along with CAR (10 mg/kg) in the respective groups of animals, ISO was administered subcutaneously to induce myocardial damage. Myocardial infarction (MI) diagnostic predictor enzymes, lactate dehydrogenase (LDH) and creatinine kinase (CK-MB), were measured in both serum and heart tissue homogenates (HTH). Superoxide dismutase (SOD), catalase, and thiobarbituric acid reactive species (TBARS) were estimated in HTH. When compared with other groups, the combined therapy of high doses of AGE and SAC given alone or together with CAR caused a significant decrease in serum LDH and CK-MB activities. Further, significant rise in the LDH and CK-MB activities in HTH was noticed in the combined groups of AGE and SAC with CAR. It was also observed that both doses of AGE and SAC significantly increased endogenous antioxidants in HTH. Furthermore, histopathological observations corroborated the biochemical findings. The cytoprotective potential of SAC and AGE were dose-dependent, and SAC was more potent than AGE. The protection offered by aged garlic may be attributed to SAC. Overall, the results indicated that a high dose of AGE and its constituent SAC, when combined with carvedilol, has a synergistic effect in preventing morphological and physiological changes in the myocardium during ISO-induced myocardial damage.  相似文献   
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203.
The plastic behavior of micro- and nano-scale crystalline pillars is investigated under nominally uniform compression. The transition from forest hardening to exhaustion hardening dominated behavior is shown to emerge from discrete dislocation dynamics simulations upon reduction in the initial source density. The analyses provide new insight into the scaling of flow stress with specimen size and also highlight the connection between individual dislocation mechanisms, collective phenomena and overall behavior.  相似文献   
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205.
In order to gauge the reliability of electronic packages, it is valuable to analyze thermally induced displacements and strains around bimaterial corners and within interconnections. The increased demand for computing performance has created increasingly complex electronic packages with miniaturized features, making it increasingly difficult to extract these quantities. Often, material properties at these length scales are not fully known, making modeling and simulation problematic. Thus, determining displacements and strains experimentally is attractive. In this study, an advanced flip-chip package with fine interconnection features was analyzed using phase-shifting moiré interferometry (PSMI) in conjunction with image analysis software developed for this purpose. Before the analysis, PSMI was qualified using an isotropic solid undergoing uniform thermal contraction, which yielded a displacement precision of ±4 nm. Then a high-magnification, high-resolution displacement and strain analysis was performed for a small cross-sectional region of the flip-chip package containing 20–100 μm sized features. The analysis quantifies these results and gives displacements and strains obtained by differentiating the displacement data using a strain-energy-based finite element formulation.  相似文献   
206.
The consecutive stepwise formation constants of 1:1 and 1:2 chelate species formed by the interaction of DC-2-CPHD and DC-3-CPHD anions with tripositive lanthanon and divalent copper, nickel, cobalt, zinc, manganese, and cadmium cations were determined potentiometrically at ionic strengh of 0.1 (KNO3) and 30°C. The results indicate that two different coordination modes, one tridentate (DC-2-CPHD), and one bidentate (DC-3-CPHD), are in evidence.  相似文献   
207.
Computer simulations were carried out to investigate the limitations imposed by atmospheric turbulence on observing astronomical objects by 3·5 and 1·25 m optical telescopes. These limitations were studied in terms of the modulation transfer function of a reference star and the autocorrelation function of a binary star. Results demonstrate the quantitative comparative study between these telescopes in the presence of different seeing conditions for both short- and long-exposure recording.  相似文献   
208.
A relaxation system based on a Lattice-Boltzmann type discrete velocity model is considered in the low Mach number limit. A third order relaxation scheme is developed working uniformly for all ranges of the mean free path and Mach number. In the incompressible Navier-Stokes limit the scheme reduces to an explicit high order finite difference scheme for the incompressible Navier-Stokes equations based on nonoscillatory upwind discretization. Numerical results and comparisons with other approaches are presented for several test cases in one and two space dimensions.

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209.
Optical Review - In this paper, we propose a full duplex architecture based on a hybrid link composed of free space optics (FSO) and multimode plastic optical fiber (MMPOF) for short-range wireless...  相似文献   
210.
Journal of Russian Laser Research - Laser side-pumping approach is an extremely attractive configuration for many laser applications. Through this approach, the laser beam can be generated in the...  相似文献   
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