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Radioprotection of mice by dietary squalene   总被引:1,自引:0,他引:1  
Male C3H mice were fed a diet containing 2% squalene for 14 d prior to and 30 d subsequent to exposure to 6, 7 or 8 Gy of whole body γ-irradiation (Cesium-137). After 14 d on squalene-supplemented diet, plasma and jejunal tissue squalene levels were 2X and 15X that of controls. Seven days after irradiation, total white cell counts and total lymphocyte counts were substantially depressed in a radiation dose-dependent manner. Although counts in the squalene group were consistently (18–119%) higher than those in the corresponding dietary control group, the differences between dietary groups at any single dose were not significant. Nuclear area of villus cells in the jejunum of both dietary groups was significantly reduced (20%) by day 11 post-irradiation but the nuclear area in squalene-fed mice was significantly greater (15%) than in controls, before and after irradiation. There were no differences in body weight as a function of either diet or radiation dose prior to the first observations of animal lethality. Animal survival was decreased from 100 to 0% at 30 d post-irradiation by radiation doses of 6–8 Gy, with the greatest difference between dietary groups being observed at 7 Gy (median survival times of 12 and 16 d for control and squalene groups, respectively). Overall, survival of squalene-fed mice was significantly prolonged compared with control-fed mice (P=0.0054 by censored multiple regression analysis). It is concluded that squalene conferred some cellular and systemic radioprotection to mice receiving these lethal whole-body radiation doses.  相似文献   
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A polymerizable-complex method (PCM) was used with automated solution deposition to generate combinatorial libraries of oxide powders that were evaluated for their ability to catalyze the combustion of soot. Chemical compositions were examined for catalytic activity in the soot combustion reaction in parallel using infrared thermography and serially using automated thermogravimetric analysis. Although infrared analysis is much faster, it is not easily suited to analyzing soot combustion in the configuration employed in the present study. Instead, the slower automated thermogravimetric analysis (TGA) was found to be much more reliable and reproducible. The results of characterizing simple oxide systems (Ce–K–O, Cu–K–O, Ce–Na–O and Cu–Na–O) are reported.  相似文献   
76.
Effective integrated water management is a key component of the World Water Vision and the way in which aspirations for water equity may be realized. Part of the vision includes the promotion of sustainability of water systems and full accountability for their interaction with other urban systems. One major problem is that “sustainability” remains an elusive concept, although those involved with the provision of urban wastewater systems now recognize that decisions involving asset investment should use the “triple bottom line” approach to society, the economy, and the environment. The Sustainable Water Industry Asset Resource Decisions project has devised a flexible and adaptable framework of decision support processes that can be used to include the principles of sustainability more effectively. Decision mapping conducted at the outset of the project has shown that only a narrow range of criteria currently influence the outcome of asset investment decisions. This paper addresses the concepts of sustainability assessment and presents two case studies that illustrate how multicriteria decision support systems can enhance the assessment of the relative sustainability of a range of options when decisions are being made about wastewater asset investment.  相似文献   
77.
Custom diamond electrodes for in vivo, passive electrical nerve recording were developed and implanted in an intact, freely behaving Aplysia californica. A diamond electrode may have advantages for electrical recording because of its chemical stability, higher signal-to-noise ratio, and reduced biological fouling relative to traditional nerve-recording electrode materials. For example, thin stainless steel electrodes used for chronic extracellular recording in Aplysia typically last on the order of seven days in vivo. We have developed a first-generation diamond electrode with a flexible lead to withstand the complicated movements of Aplysia and to enable direct comparison with implanted stainless steel electrodes.Boron-doped polycrystalline diamond was grown onto tungsten wire substrates by hot filament chemical vapor deposition. The wires were pre-shaped into a hook (for nerve recording) or a loop (for a ground wire) and masked for selective growth on only 2–3 mm of the wire. After diamond growth, the uncoated portion of the wire substrates was removed and the intact diamond-coated hook or loop attached to a stainless steel electrical lead with conductive epoxy. After epoxy curing, these electrodes were insulated and implanted in the animal.The diamond and stainless steel electrodes were attached extracellularly to buccal nerve 2, a primary nerve for the feeding behavior of A. californica. The two electrodes were implanted adjacent to each other so that the recordings would be nearly synchronous. In vivo recordings were successfully obtained on a diamond hook electrode during a feeding behavior for up to 9 days after the implantation. The electrode remained intact for a total of 28 days in the animal and upon retrieval.  相似文献   
78.
Compared the effects of self-control training, using cognitive-behavioral game play (CB) and biofeedback game play (BF), on the behaviors of 58 male and 5 female 8–12 yr olds with Full Scale IQ of 90 or higher on the Wechsler Intelligence Scale for Children--Revised (WISC--R) and diagnosed with attention deficit hyperactivity disorder (ADHD). The experimental groups were compared to a control game group (GC), which received no self-control training. A 3?×?3 (treatment?×?time) factorial design with repeated measures, using IQ as a covariate, and multiple outcome criteria was employed comparing the groups. Findings support the hypothesis that self-control training by BF reduces a child's perception of his or her self-control problems, but the same does not generalize to parental report of self-control or behavioral measures. Hyperactivity, one of the cardinal symptoms of ADHD, was significantly decreased in GC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Solution-processable organic conductor–supramolecular elastomer blends are emerging materials for intrinsically stretchable and autonomously self-healing organic electronics. Herein, the feasibility of a heterogenous multiphase polymer blend is demonstrated for soft, ultraflexible, self-adhesive, and self-healing multilayered film structures for electromagnetic interference (EMI) shielding and microwave absorber (MWA) purposes. The developed soft multilayered films achieve a 5–40 fold improvement in the thickness of the MWA compared to the current state-of-the-art. The thickness normalized reflection loss (RL) is up to 65.26 dB mm−1 with 8.5 GHz bandwidth at 18–26.5 GHz. The maximum thickness normalized EMI shielding effectiveness peaks at up to 175 dB mm−1. The EMI shielding and MWA properties are maintainable up to 150% tensile strain with only a small decrease in the overall attenuation and RL. Furthermore, the developed films are capable of fully autonomously self-healing and achieve a tough adhesion in temperatures of −30–145 °C, and underwater with maximum single-lap shear adhesion strength of ≈481.5 kPa to soft thermoplastic polyurethane films. Thus, the developed multilayered films can be utilized for absorption-dominant EMI shielding or MWA purposes as stretchable coatings. The developed materials also show considerable potential for emerging damage and puncture-resistant organic soft electronics with autonomous material-level self-healing.  相似文献   
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Inhaled Aspergillus fumigatus spores can be internalized by alveolar type II cells. Cell lines stably expressing fluorescently labeled components of endocytic pathway enable investigations of intracellular organization during conidia internalization and measurement of the process kinetics. The goal of this report was to evaluate the methodological appliance of cell lines for studying fungal conidia internalization. We have generated A549 cell lines stably expressing fluorescently labeled actin (LifeAct-mRuby2) and late endosomal protein (LAMP1-NeonGreen) following an evaluation of cell-pathogen interactions in live and fixed cells. Our data show that the LAMP1-NeonGreen cell line can be used to visualize conidia co-localization with LAMP1 in live and fixed cells. However, caution is necessary when using LifeAct-mRuby2-cell lines as it may affect the conidia internalization dynamics.  相似文献   
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