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1.
肝脂质代谢异常导致过度肝脂肪沉积和脂肪变性是脂肪肝发展的关键环节.胱硫脒-伽马-裂解酶(CSE)是在肝脏中催化硫化氢(H2S)生成的酶之一.本研究的目的是研究CSE/H2S在调控肝脏胆固醇和脂肪酸代谢中的作用.用高脂饮食(HFD)喂食野生型(WT)和CSE敲除(KO)小鼠后,对小鼠肝形态学和生物化学变化进行了分析.与WT小鼠不同,HFD喂食显著增加CSE-KO小鼠的血浆和肝脏胆固醇水平以及肝和胆囊的大小.这些CSE-KO小鼠呈现典型的脂肪肝组织学和生物化学变化以及肝功能损害.血浆和肝脏甘油三酯水平也比HFD喂养WT小鼠显著降低.核受体转录因子LXRα以及它的靶基因,CYP7A1,在对照组和HFD组CSE-KO小鼠肝脏中的表达都低于相应WT小鼠的水平.这些异常阻碍胆固醇分解成胆汁并导致胆固醇蓄积在肝脏和胆囊.由于CSE/H2S通路缺失造成对HFD诱导的脂肪肝的高易感性,肝脏CSE/H2S通路可能是治疗脂肪肝损伤的一个新的靶向. 相似文献
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Sensor networks are deployed in many application areas nowadays ranging from environment monitoring, industrial monitoring, and agriculture monitoring to military battlefield sensing. The accuracy of sensor readings is without a doubt one of the most important measures to evaluate the quality of a sensor and its network. Therefore, this work is motivated to propose approaches that can detect and repair erroneous (i.e., dirty) data caused by inevitable system problems involving various hardware and software components of sensor networks. As information about a single event of interest in a sensor network is usually reflected in multiple measurement points, the inconsistency among multiple sensor measurements serves as an indicator for data quality problem. The focus of this paper is thus to study methods that can effectively detect and identify erroneous data among inconsistent observations based on the inherent structure of various sensor measurement series from a group of sensors. Particularly, we present three models to characterize the inherent data structures among sensor measurement traces and then apply these models individually to guide the error detection of a sensor network. First, we propose a multivariate Gaussian model which explores the correlated data changes of a group of sensors. Second, we present a Principal Component Analysis (PCA) model which captures the sparse geometric relationship among sensors in a network. The PCA model is motivated by the fact that not all sensor networks have clustered sensor deployment and clear data correlation structure. Further, if the sensor data show non-linear characteristic, a traditional PCA model can not capture the data attributes properly. Therefore, we propose a third model which utilizes kernel functions to map the original data into a high dimensional feature space and then apply PCA model on the mapped linearized data. All these three models serve the purpose of capturing the underlying phenomenon of a sensor network from its global view, and then guide the error detection to discover any anomaly observations. We conducted simulations for each of the proposed models, and evaluated the performance by deriving the Receiver Operating Characteristic (ROC) curves. 相似文献
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The treatment of 100 MeV Ag swift-heavy ion(SHI) irradiation with five different fluences(3 1010, 1 1011, 3 1011, 1 1012, and3 1012ions/cm2) was used to design optical and structural properties of amorphous(a-) As40Se60 chalcogenide thin films. Swanepoel method was applied on transmission measurements to determine the changes in optical bandgap, Tauc parameter and linear optical parameters, i.e., linear optical absorption, extinction coefficient and linear refractive index. Dispersion of the material was determined by Wemple–DiDomenico relation.Changes in nonlinear optical parameters of third-order optical susceptibility and nonlinear refractive index were determined using semi-empirical relations. Changes in surface morphology of the films were investigated using SEM observation, which indicated that fluence 3 1012ions/cm2was upper threshold limit for these films for ion treatment. It is observed that optical bandgap reduces from 1.76 eV to 1.64 eV, and nonlinear refractive index increases from 1.31 10 10[esu] to 1.74 10 10[esu]. Linear refractive index initially increases from 2.80 to 3.52(for fluence3 1010ions/cm2) and then keeps decreasing. The observed changes in optical properties upon irradiation were explained in terms of structural rearrangements by Raman measurement. The study was compiled with the previous literature to propose SHI as an effective optical engineering technique to achieve desired changes according to the need of optical/photonic applications. 相似文献
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A cycle of activity of aldehyde-fuchsin and performic acid-Victoria blue positive granules was observed in the ovarian pedicle of Dysdercus koenigii during the first ovipositional cycle. The quantitative variation of these granules in the pedicle can also be correlated directly with the increase or decrease of the neurosecretory material in the A-type cells of the pars intercerebralis medialis region of the protocerebrum of the brian. 相似文献
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J. K. Saxena S. Khare A. K. Srivastava A. B. Sen S. Ghatak 《Cellular and molecular life sciences : CMLS》1985,41(4):472-474
Summary Changes in liver acid hydrolase activities during the infection of albino rats,Mastomys or mice withPlasmodium berghei are described. B-Glucosidase, B-galactosidase and N-acetyl-B-D-glucosaminidase exhibited widely different responses with acid phosphatase and cathepsin-B the least responsive and are likely to be causally related to immunity of animals. 相似文献
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1 Results Classic oxidants require rigorous control of the experimental conditions added with the problem of lack of selectivity. Catalysis by transition metals with environmentally safe oxidants provides synthetic routes to minimize pollution by giving environmental benign by-products. Fe (Ⅵ) is a powerful and a selective oxidant with Fe(Ⅲ) as a by-product, while hydrogen peroxide is clean with water as the only by-product. Separation of sodium or potassium ferrates requires tedious processes. Associat... 相似文献
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Zusammenfassung Die Scholanderschen Befunde über den Sauerstofftransport durch Hämoglobinlösungen werden auf der Basis der irreversiblen Thermodynamik behandelt. 相似文献
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