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排序方式: 共有1454条查询结果,搜索用时 15 毫秒
41.
Sylvain Lamoine Mlissa Cumenal David A. Barriere Vanessa Pereira Mathilde Fereyrolles Laëtitia Prival Julie Barbier Ludivine Boudieu Emilie Brasset Benjamin Bertin Yoan Renaud Elisabeth Miot-Noirault Marie-Ange Civiale David Balayssac Youssef Aissouni Alain Eschalier Jrme Busserolles 《International journal of molecular sciences》2022,23(1)
42.
Gracia Fahed Laurence Aoun Morgan Bou Zerdan Sabine Allam Maroun Bou Zerdan Youssef Bouferraa Hazem I. Assi 《International journal of molecular sciences》2022,23(2)
Metabolic syndrome (MetS) forms a cluster of metabolic dysregulations including insulin resistance, atherogenic dyslipidemia, central obesity, and hypertension. The pathogenesis of MetS encompasses multiple genetic and acquired entities that fall under the umbrella of insulin resistance and chronic low-grade inflammation. If left untreated, MetS is significantly associated with an increased risk of developing diabetes and cardiovascular diseases (CVDs). Given that CVDs constitute by far the leading cause of morbidity and mortality worldwide, it has become essential to investigate the role played by MetS in this context to reduce the heavy burden of the disease. As such, and while MetS relatively constitutes a novel clinical entity, the extent of research about the disease has been exponentially growing in the past few decades. However, many aspects of this clinical entity are still not completely understood, and many questions remain unanswered to date. In this review, we provide a historical background and highlight the epidemiology of MetS. We also discuss the current and latest knowledge about the histopathology and pathophysiology of the disease. Finally, we summarize the most recent updates about the management and the prevention of this clinical syndrome. 相似文献
43.
N. A. Shams A. M. Kaddah E. I. Enayat Alyaa A. Shalaby A. M. Youssef 《Advanced Synthesis \u0026amp; Catalysis》1989,331(5):757-762
Reaction of acrylonitrile with 4-cyano-5,6-diphenyl pyridazin-3(2H)-one and 3(2H)-thione derivative ( 1a, b ) at elevated temperature gave 7H-5-amino-6-cyano-3,4-diphenylpyrano and thiino [2,3-c] pyridazines ( 2a, b ), respectively. However, the reaction of 4-carbethoxy pyridazine derivatives ( 1c, d ) with the same reagent, under the same conditions afforded 6H, 7H-6-cyano-3,4-diphenyl-5-oxopyrano ( 3a ) and thiino [2,3-c] pyridazine ( 3b ), respectively. In addition, treatment of ( 1a, c ) and ( 1b, d ) with acrylonitrile ar reflux in alkaline medium give the respective 3-(2′-cyanoethyloxo) ( 7a, c ) and 3-2′-cyanoethylthio ( 7b, d ) pyridazine derivatives. Prolonged alkaline hydrolysis of either ( 1a, c ) or ( 7a, c ) yielded the same product ( 8a ). Also hydrolysis of ( 1b, d ) and ( 7b, d ) afforded one and the same product ( 8b ). The structures of the products were assigned on the basis of satisfactory analytical and spectroscopic data. 相似文献
44.
H. A. Abou-Gharbia F. Shahidi A. Adel Y. Shehata M. M. Youssef 《Journal of the American Oil Chemists' Society》1997,74(3):215-221
Oxidative stability of oils extracted from intact and dehulled sesame seeds was determined by monitoring changes in fatty
acid composition, iodine value (IV), peroxide value (PV), conjugated diene (CD), para-anisidine value (p-AV), and 2-thiobarbituric acid (TBA) value and by nuclear magnetic resonance spectroscopy after storage under Schaal oven
conditions at 65°C for up to 35 d. The oils from coated seeds were more stable, as reflected in PV, CD, p-AV and TBA values, than those extracted from dehulled seeds after roasting at 200°C, steaming at 100°C, roasting at 200°C
plus steaming, or microwaving at 2450 MHz, except for TBA values of oil from microwaved seeds. After 35 d of storage at 65°C,
the CD, p-AV, and TBA values of extracted oil from dehulled microwaved seeds were 17.72, 10.20, and 1.22, respectively, while those
of their coated counterparts were significantly (P<0.05) different at 14.20, 16.47, and 1.26, respectively. Few significant changes were evident in the fatty acid composition
of oil obtained from either coated and dehulled seeds subjected to different treatments. Nuclear magnetic resonance analyses
found that Rao (aliphatic to olefinic protons) and Rad (aliphatic to diallylmethylene protons) ratios increased steadily over the entire storage period, which indicated progressive
oxidation of unsaturated fatty acids. 相似文献
45.
Hasanin Mohamed Sharmoukh Walid Hassan Youssef R. El Saied Houssni 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(2):667-677
Journal of Inorganic and Organometallic Polymers and Materials - Historically, the recording of information over paper has always been regarded as the most important factor for maintaining records... 相似文献
46.
Hierarchial Zeolites: Beyond Creation of Mesoporosity: The Advantages of Polymer‐Based Dual‐Function Templates for Fabricating Hierarchical Zeolites (Adv. Funct. Mater. 12/2016)
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47.
Emna Hmani Sourour Chaabane Elaoud Youssef Samet Ridha Abdelhdi 《Journal of hazardous materials》2009,170(2-3):928-933
Electrochemical oxidation of O-Toluidine (OT) was studied by galvanostatic electrolysis using lead dioxide (PbO2) and boron-doped diamond (BDD) as anodes. The influence of operating parameters, such as current density, initial concentration of OT and temperature was investigated. Measurements of chemical oxygen demand were used to follow the oxidation. The experimental data indicated that on PbO2 and BDD anodes, OT oxidation takes place by reaction with electrogenerated hydroxyl radicals and is favoured by low current density and high temperature. Furthermore, BDD anodes offer significant advantages over PbO2 in terms of current efficiency and oxidation rate. 相似文献
48.
Youssef Travaly Mikhail Baklanov 《集成电路应用》2009,(1):37-40
随着对新化学品和集成方案了解的加深,我们不但可以减轻介电层孔隙率增加引起的负担还可以降低工艺对超低k薄膜的损伤。 相似文献
49.
Study of features based on nonlinear dynamical modeling in ECG arrhythmia detection and classification 总被引:3,自引:0,他引:3
Owis MI Abou-Zied AH Youssef AB Kadah YM 《IEEE transactions on bio-medical engineering》2002,49(7):733-736
We present a study of the nonlinear dynamics of electrocardiogram (ECG) signals for arrhythmia characterization. The correlation dimension and largest Lyapunov exponent are used to model the chaotic nature of five different classes of ECG signals. The model parameters are evaluated for a large number of real ECG signals within each class and the results are reported. The presented algorithms allow automatic calculation of the features. The statistical analysis of the calculated features indicates that they differ significantly between normal heart rhythm and the different arrhythmia types and, hence, can be rather useful in ECG arrhythmia detection. On the other hand, the results indicate that the discrimination between different arrhythmia types is difficult using such features. The results of this work are supported by statistical analysis that provides a clear outline for the potential uses and limitations of these features. 相似文献
50.
Solouma NH Youssef AB Badr YA Kadah YM 《IEEE transactions on bio-medical engineering》2002,49(9):1059-1067
A new system is proposed for tracking sensitive areas in the retina for computer-assisted laser treatment of choroidal neovascularization (CNV). The system consists of a fundus camera using red-free illumination mode interfaced to a computer that allows real-time capturing of video input. The first image acquired is used as the reference image and utilized by the treatment physician for treatment planning. A grid of seed contours over the whole image is initiated and allowed to deform by splitting and/or merging according to preset criteria until the whole vessel tree is demarcated. Then, the image is filtered using a one-dimensional Gaussian filter in two perpendicular directions to extract the core areas of such vessels. Faster segmentation can be obtained for subsequent images by automatic registration to compensate for eye movement and saccades. An efficient registration technique is developed whereby some landmarks are detected in the reference frame then tracked in the subsequent frames. Using the relation between these two sets of corresponding points, an optimal transformation can be obtained. The implementation details of proposed strategy are presented and the obtained results indicate that it is suitable for real-time location determination and tracking of treatment positions. 相似文献