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611.
The liver extended a minimum of 5 cm inferior to the right costal margin in 51% of the 504 patients studied. In 53% of these patients, experienced, mature physicians declared that the liver was not palpable on physical examination. In 3% of the cases, a mass was palpated which was believed to be liver by the examining physician but was found to be extrahepatic upon scanning and laparotomy. The unreliability of physical examination in determining whether or not the liver extends inferior to the costal margin in many instances is demonstrated.  相似文献   
612.
Tap water quality was examined in six sampling events over a 2-year period in a residential community of Greater Cairo, Egypt. The sampling sites chosen had a granular activated carbon (GAC), reverse osmosis (RO) or distillation point-of-use (POU) treatment device so that the performance of these units for standard water quality parameters could be evaluated. Tap water satisfied Egyptian and international drinking water standards and guidelines for the majority of samples analysed. Exceptions were the violation of international limits for lead in 10 samples, and total trihalomethane (TTHM) levels that occasionally exceeded drinking water limits. Only the RO and distillation units achieved removal of total dissolved solids (TDS), alkalinity and hardness. However, GAC units are considerably less costly in the local market. All three POU units exhibited potential reduction of chemical contaminants such as trihalomethanes (THMs), improved taste via chlorine removal and improvement in clarity. Realization of these benefits, however, is conditioned upon proper operation and maintenance of the device.  相似文献   
613.
A general solution is given for the elastic thermal stresses in a solid or hollow anisotropic disc of constant thickness when subjected to a temperature rise which varies symmetrically in an axial direction and arbitrarily with the radius. Graphs demonstrate the variations of stress distribution and maximum stresses with the degree of anisotropy and other parameters.  相似文献   
614.
The intriguing properties of two‐dimensional transition metal dichalcogenides (2D TMDCs) have led to a significant body of fundamental research and rapid uptake of these materials in many applications. Specifically, 2D TMDCs have shown great potential in biological systems due to their tunable electronic characteristics, unique optical properties, stability in aqueous environments, large surface area that can be manipulated and functionalized as well as an intercalatable layered structure, and low levels of toxicity. Here, the characteristics and use of 2D TMDCs for biological applications are reviewed and future possibilities for these materials in biological systems are outlined.  相似文献   
615.
A nematic liquid crystal spatial light modulator used as a phase-modulating device and operating in the reflective mode is analyzed using three-dimensional modeling. Two configurations, which differ in their electrode placement relative to a fixed quarter-wave plate, are considered across a range of steering directions, with the grating conformal and in some cases oblique to the pixel grid. For each steering direction the sensitivity of the diffraction orders to the polarization state of the incident wavefront is studied. Optimal alignment of the liquid crystal is suggested to reduce this sensitivity.  相似文献   
616.
The current study was designed to investigate the protective role of diosmin against cyclophosphamide-induced premature ovarian insufficiency (POI). Female Swiss albino rats received a single intraperitoneal dose of cyclophosphamide (200 mg/kg) followed by 8 mg/kg/day for the next 15 consecutive days either alone or in combination with oral diosmin at 50 or 100 mg/kg. Histopathological examination of ovarian tissues, hormonal assays for follicle stimulating hormone (FSH), estradiol (E2), and anti-Mullerian hormone (AMH), assessment of the oxidative stress status, as well as measurement of the relative expression of miRNA-145 and its target genes [vascular endothelial growth factor B (VEGF-B) and regulator of cell cycle (RGC32)] were performed. Diosmin treatment ameliorated the levels of E2, AMH, and oxidative stress markers. Additionally, both low and high diosmin doses significantly reduced the histopathological alterations and nearly preserved the normal ovarian reserve. MiRNA-145 expression was upregulated after treatment with diosmin high dose. miRNA-145 target genes were over-expressed after both low and high diosmin administration. Based on our findings, diosmin has a dose-dependent protective effect against cyclophosphamide-induced ovarian toxicity in rats.  相似文献   
617.
This paper explores some design possibilities and constraints for 3D enhancements of graphical user interfaces (GUIs). This is done with the aim of conveying more information in less screen space, while avoiding visual clutter. Design elements include the use of ‘slapped‐back’ windows obtained by projecting windows and icons into three dimensions; ‘trays’, an alternative to folders or piles; the use of transparent ‘beams’ for indicating hierarchy; and the use of ‘periphs’ for a form of fisheye projection on window borders. In addition we employ shading and shadows to enhance the interface, and automatic placement algorithms to prevent visually confusing occlusion. By considering these approaches together, rather than in isolation, the interactions between the different modifications are made explicit. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
618.
This communication reports an MgF2/ZnO/CdS/Cu(In,Ga)Se2/Mo/glass polycrystalline solar cell with a confirmed total-area conversion efficiency of 16.4%. the thin-film Cu(In,Ga)Se2 absorber was fabricated by computer-controlled physical vapor deposition (PVD) from the elemental sources. the resulting absorber has a Gal/In compositional grading that we refer to as a notch. Capacitance-voltage (C-V) measurements also reveal a graded doping profile in the region near the electronic p-n junction. the enhanced device performance is characterized by an open-circuit voltage (Voc) of 660 mV and a particularly high fill factor (FF) of 78.7%.  相似文献   
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