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61.
The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C24H22N2O2S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a?=?19.7799(13) Å, b?=?6.7473(4) Å, c?=?15.7259(9) Å and β?=?103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations. 相似文献
62.
63.
Francisco J Gálvez-Gastélum Aida A Segura-Flores María D Senties-Gomez Jose F Muñoz-Valle Juan S Armendáriz-Borunda 《Journal of biomedical science》2010,17(1):42
Background
Liver fibrosis ranks as the second cause of death in México's productive-age population. This pathology is characterized by acummulation of fibrillar proteins in hepatic parenchyma causing synthetic and metabolic disfunction. Remotion of excessive fibrous proteins might result in benefit for subjects increasing survival index. The goal of this work was to find whether the already known therapeutical effect of human urokinase Plasminogen Activator and human Matrix Metalloprotease 8 extends survival index in cirrhotic animals. 相似文献64.
65.
Four main molecular forms of acetylcholinesterase (AChE) can be solubilized from newborn rat superior cervical ganglia (SCG), homogenized in the presence of a high-ionic-strength, detergent-containing medium. These forms, respectively referred to as 16, 10, 6.5, and 4 S, are characterized by their sedimentation coefficients. Their relative proportions in SCG are notably different in vivo during postnatal maturation, and in culture. The 16-S AChE appears to be mainly neuronal in origin, is maintained in culture independently of original presynaptic in vivo elements, and its cellular pool is not depleted in the presence of tetrodotoxin (TTX). 相似文献
66.
67.
Mari Cruz Díaz-Barradas María Zunzunegui Fatima Ain-Lhout Juan Jáuregui Said Boutaleb Leonor Álvarez-Cansino Mari Paz Esquivias 《Plant and Soil》2010,337(1-2):217-231
Argania spinosa (the argan tree) is a slow-growing tree endemic of Morocco, growing on semi-arid areas where no other tree species can live. With the aim of predicting temporal changes in A. spinosa woodlands under a probable increase in aridity, we set off to investigate these questions: how do A. spinosa physiological attributes respond to variations in climatic conditions and seasonality, and which is the set of attributes that most affects tree response to environmental conditions? In three study sites, Beni Snassen (North), High-Atlas (Mountain) and Admine Forest in Agadir (Coastal), gas exchange measurements, photochemical efficiency, leaf water potential and different leaf attributes were monitored in February, July and November of 2006. The Mountain site presents the most continental climate. Trees in this site were the most stressed in summer, having the lowest midday leaf water potential values, photochemical efficiency and assimilation rates. We found a Ψmd threshold around -4 MPa, below which stomatal conductance responds linearly to Ψmd. Plants from the North area never reached this threshold during the study period. Although leaf pigments presented a clear seasonal pattern, leaves from Coastal trees exhibit the highest content for each season. The three study sites were separated by two discriminate functions obtained by canonical discriminant analysis. In summer, the Mountain population is separated from the other sites mainly by assimilation rate and Fv/Fm, while in winter transpiration rates and chlorophyll content are the main discriminant variables. Our study shows that A. spinosa trees adjust their physiological status and leaf attributes to environmental conditions allowing plants to thrive under a dry climate. Under a scenario of global change, the distribution of the argan tree likely shifts to milder areas. 相似文献
68.
Samuel García Myriam Liz Juan J Gómez-Reino Carmen Conde 《Arthritis research & therapy》2010,12(1):R33
Introduction
Synovial hyperplasia is a main feature of rheumatoid arthritis pathology that leads to cartilage and bone damage in the inflamed joints. Impaired apoptosis of resident synoviocytes is pivotal in this process. Apoptosis resistance seems to involve defects in the extrinsic and intrinsic apoptotic pathways. The aim of this study was to investigate the association of PI3Kinase/Akt and the mitochondrial apoptotic pathway in the resistance of rheumatoid arthritis (RA) fibroblast like synovial cells (FLS) to Fas-mediated apoptosis. 相似文献69.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
70.
Protective effect of long term ammonium ingestion against acute ammonium intoxication 总被引:4,自引:0,他引:4
M D Mi?ana V Felipo S Grisolía 《Biochemical and biophysical research communications》1988,153(3):979-983
Rats were fed for 15 days a diet containing ammonium acetate (20% w/w) and then injected i. p. with ammonium acetate (7 mmol/Kg). Only 1 out of 18 control rats but 9 of 18 rats fed ammonium survived, indicating a protective effect of ammonium ingestion against an acute ammonia challenge. Blood ammonia returned to normal levels sooner in hyperammonemic rats, suggesting more rapid detoxication. In controls, blood urea levels rose immediately reaching a maximum at 15 min, however in hyperammonemic rats urea levels did not change during the first hour, then rose slowly up to 3 hours. These results suggest that in the ammonium fed rats ammonia is initially sequestered and finally eliminated as urea. 相似文献