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Bioassay-Guided Extraction of Crude Fucose-Containing Sulphated Polysaccharides from Sargassum fusiforme with Response Surface Methodology 被引量:2
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作者 FU Zhifei LI Haihua +4 位作者 LIU Hongbing HU Shuman LI Yueying WANG Mengxue GUAN Huashi 《Journal of Ocean University of China》 SCIE CAS 2016年第3期533-540,共8页
The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composit... The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future. 展开更多
关键词 crude fucose-containing sulphated polysaccharides Sargassum fusiforme response surface methodology immuno-modulatory
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Geogenic Pollution of Groundwater Quality in Gampaha District, Sri Lanka: A Case Study of Groundwater Acidification from Rathupaswala
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作者 Ishara Pathirage Anushka Upamali Rajapaksha +1 位作者 S. P. Sucharitha Bandara G. W. A. Rohan Fernando 《International Journal of Geosciences》 CAS 2024年第8期590-604,共15页
Over recent decades, Gampaha district, Sri Lanka, has experienced significant urbanisation and industrial growth, increasing groundwater demand due to limited and polluted surface water resources. In 2013, a community... Over recent decades, Gampaha district, Sri Lanka, has experienced significant urbanisation and industrial growth, increasing groundwater demand due to limited and polluted surface water resources. In 2013, a community uprising in Rathupaswala, a village in Gampaha district, accused a latex glove manufacturing factory of causing groundwater acidity (pH < 4). This study evaluates the spatial and temporal changes in geochemical parameters across three transects in the southern part of Gampaha district to 1) assess the impact of geological formations on groundwater;2) compare temporal variations in groundwater;and 3) explain acidification via a geochemical model. Seventy-two sample locations were tested for pH, electrical conductivity (EC), and anion concentrations (sulphate, nitrate, chloride and fluoride). Depth to the water table and distance from the sea were measured to study variations across sandy, peaty, lateritic, and crystalline aquifers. Results showed pH readings around 7 for sandy and crystalline aquifers, below 7 for peaty aquifers, and below 5 for lateritic aquifers, with significant water table fluctuations near Rathupaswala area. Principal component analysis revealed three principal components (PCs) explaining 86.0% of the variance. PC1 (40.6%) correlated with pH, EC, and sulphate (saltwater intrusion), while PC2 (32.0%) correlated with nitrates and depth to the water table (anthropogenic nutrient pollution). A geochemical transport model indicated a cone of depression recharged by acidic groundwater from peat-soil aquifers, leading to acidic groundwater in Rathupaswala area. Previous attributions of acidic pH to the over-exploitation of groundwater by the latex factory have been reevaluated;the results suggest natural acidification from prolonged water-rock interactions with iron-rich lateritic aquifers. Groundwater pH is influenced by local climate, geology, topography, and drainage systems. It is recommended that similar water-rock interaction conditions may be present throughout the wet zone of Sri Lanka, warranting detailed studies to confirm this hypothesis. 展开更多
关键词 Groundwater Acidification Acid Sulphate Soils (AAS) Ion Chromatography Groundwater Quality
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Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation 被引量:2
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作者 Sílvia Sousa Chambel Célia Duarte Cruz 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2573-2581,共9页
Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibi... Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment. 展开更多
关键词 chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19
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Fixed-Dose Combination (FDC) Formulation of Quinine Sulphate-Doxycycline (Qidox) for Malaria Therapy
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作者 Widyati Widyati Timbul Partogi H. Simorangkir +3 位作者 Syahrul Tuba Taufiq Riyadi Yuda Prasetya Nugraha William Ratna Prawira 《Journal of Biosciences and Medicines》 CAS 2023年第1期184-194,共11页
Background: One of the deadliest parasite infections is malaria. A combination of quinine sulphate and doxycycline is another therapeutic option for malaria that is resistant to chloroquine and is anticipated to be ab... Background: One of the deadliest parasite infections is malaria. A combination of quinine sulphate and doxycycline is another therapeutic option for malaria that is resistant to chloroquine and is anticipated to be able to both combat the issue of anti-malarial medication resistance as well as the compliance to malaria therapy that is still raging in certain locations of Indonesia. Aim: This study will focus on evaluating the possibility of interaction between quinine sulphate and doxycycline followed by formulating the fixed-dose combination of both active pharmaceutical ingredients. Method: The study was designed as a laboratory experiment and applied some examinations. The examination from the organoleptic test of active pharmaceutical ingredients powder, crystallography analysis, and physical analysis of fixed-dose tablet including hardness, friability, and disintegration time testing. Result: The crystallography study reported there was no physical interaction found between quinine sulphate and doxycycline. The formula found excellent tablet printability with a composition of Quinine sulphate and doxycycline (Qidox). Conclusion: quinine sulphate with doxycycline can be combined into one tablet as Fixed-Dose Combination (FDC). 展开更多
关键词 MALARIA Quinine Sulphate DOXYCYCLINE FDC
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Microstructure and Permeability of Concrete with Glass Powder Addition Preserved in the Sulphatic Environment
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作者 Rabah Chaïd 《Journal of Civil Engineering and Architecture》 2023年第7期343-357,共15页
Most mechanical properties and durability of cementitious materials are related to the performance of the hydrated cement that coats the granular skeleton.In this paper,concrete is formulated by substituting 30%of cem... Most mechanical properties and durability of cementitious materials are related to the performance of the hydrated cement that coats the granular skeleton.In this paper,concrete is formulated by substituting 30%of cement by finely ground glass powder.The experimental study consists of investigating the effect of conservation in tap water or sulfate water on the performance of concrete.The mechanisms of concrete damage have been related to the development of the microstructure of the material.The degradations were observed using scanning electron microscope(SEM)and quantified by x-ray diffraction(XRD).In addition,chloride ions permeability and gas permeability tests were performed.The results have shown that glass powder present a pozzolanic activity and hence it affects favorably the microstructure of the paste which becomes denser and less permeable. 展开更多
关键词 CONCRETE GLASS PERMEABILITY MICROSTRUCTURE sulphate
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缢蛏滩涂养殖环境的细菌群落组成及分析 被引量:10
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作者 金珊 薛超波 +3 位作者 王国良 陆彤霞 王一农 陈寅儿 《应用生态学报》 CAS CSCD 北大核心 2005年第7期1380-1382,共3页
In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,a... In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,ammonifying bacteria,denitrifying bacteria,and sulphate reducing bacteria were analyzed.The results showed that all the 515 isolated bacteria mainly belonged to 1 family and 13 genera.The bacterial flora in different layers of the mud was almost consistent,while the composition was different.The predominant genera were Clostridium,Bacillus,Corynebacterium,Photobacterium,and some Enterobacteriaceae.The number of heterotrophic bacteria in the surface layer and the bottom fluctuated in 7.6×103 cfu·g-1~2.0×105 and 1.6×103~1.0×105 cfu·g-1,ammonifying bacteria fluctuated in 1.5×106~9.0×107 and 9.0×105~1.0×107 cfu·g-1,denitrifying bacteria fluctuated in 9.0×103~4.0×106 and 5.0×102~1.9×106 cfu·g-1,and sulphate reducing bacteria fluctuated in 5.0×104~5.0×106 and 1.9×104~2.0×106 cfu·g-1,respectively.The detection rates of ammonifying bacteria,denitrifying bacteria and sulphate reducing bacteria in the mud were all 100%,and these bacteria increased significantly in the second half of the year,indicating that the environment of the Sinonovacula constricta aquaculture area was deteriorated due to the accumulation of NH3,nitrite and H2S,and it is important to regulate the breed capacity and redistribute the breeding environment. 展开更多
关键词 Sinonovacula constricta Tidal-flat area HETEROTROPHIC BACTERIA Ammonifying BACTERIA Denitrifying BACTERIA Sulphate REDUCING BACTERIA
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Effect of MnO_4^- and silver content on electrochemical behaviour of Pb-Ag alloy anodes during potential decay periods 被引量:4
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作者 张伟 涂常青 +2 位作者 陈艺锋 Houlachi GEORGEOS 肖利 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2174-2180,共7页
The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay ... The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy (EIS) analysis. 展开更多
关键词 electrochemical behaviour Pb-Ag anode permanganate ion potential decay periods zinc sulphate electrolyte
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Effects of Urea Ammonium Chloride of Different Fertilization Patterns on Maize Yield and Yield Components 被引量:1
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作者 曾林 赵盈风 +6 位作者 宋云飞 陆顺生 刘艳 单艳 钱光秀 杨久才 马丽敏 《Agricultural Science & Technology》 CAS 2015年第7期1462-1466,共5页
[Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different f... [Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different fertilization patterns on summer maize yield and yield components. [Results] Urea ammonium chloride had a long fertilizer effect and the same yield-increasing effect with urea, which could im- prove the agronomic traits and economic traits of maize apparently and the applica- tion of urea ammonium chloride with nutrient reduction of 40% (namely just use urea ammonium chloride equaled 60% pure nitrogen), had the same yield-increasing effect with urea of traditional fertilization patterns, and input-output ratio was high and the economic benefit was remarkable. [Conclusion] To provide scientific theoretical direc- tion for large area popularization and application of urea ammonium chloride. 展开更多
关键词 MAIZE UREA Urea ammonium chloride Calcium superphosphate Potas- sium sulphate YIELD Yield Components
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Corrosion behaviour of die-cast AZ91D magnesium alloys in sodium sulphate solutions with different pH values 被引量:5
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作者 田赟 杨丽景 +4 位作者 李艳芳 卫英慧 侯利锋 李永刚 Ri-Ichi MURAKAMI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期912-920,共9页
The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the ... The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the corrosion products were studied by means of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffractometry (XRD). The results indicate that the order of corrosion rates in Na 2 SO 4 solutions with various pH values is pH 2pH 4pH 7pH 9pH 12. The corrosion rates in acidic solutions are higher than those in alkaline solutions, and the corrosion products are mainly magnesium hydroxide (Mg(OH) 2 ) and hydrated sulphate pickeringite (MgAl 2 (SO 4 ) 4 ·22H 2 O). The results also indicate that the solution pH can influence the corrosion rate and morphology of corrosion products. Chloride ions and sulphate ions have different pitting initiation time. 展开更多
关键词 magnesium alloy CORROSION sodium sulphate pH value
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Isolation and Identification of Flavonoids Found in Zostera marina Collected in Norwegian Coastal Waters
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作者 Kjersti Hasle Enerstvedt Monica Jordheim Øyvind M. Andersen 《American Journal of Plant Sciences》 2016年第7期1163-1172,共10页
In extracts of the seagrass Zostera marina, collected in coastal waters of West-Norway, fourteen different flavones and high amounts of rosmarinic acid were identified. Five of the flavones were found to be sulphated,... In extracts of the seagrass Zostera marina, collected in coastal waters of West-Norway, fourteen different flavones and high amounts of rosmarinic acid were identified. Five of the flavones were found to be sulphated, among these were luteolin 7,3'-disulphate and chrysoeriol 7-sulphate structures previously not published with complete NMR assignments. Luteolin 7-O-β-(6''-malonyl) glucoside, and two other malonylated flavone compounds occurring in trace amounts, were identified for the first time in Z. marina. The sulphated flavones were fairly stable in slightly acidified (0.1% trifluoroacetic acid) extracts stored for months, however, under more acidic conditions (0.5% trifluoroacetic acid in the extracts) they were susceptible to undergo hydrolyses. When the solvents of purified fractions were removed by rotary evaporation, the sulphated flavones quickly decomposed to their corresponding aglycones due to the increased acid concentrations. 展开更多
关键词 Zostera marina sulphated Flavones NMR Spectral Data CHARACTERIZATION STABILITY
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Recovery of iron from waste ferrous sulphate by co-precipitation and magnetic separation 被引量:5
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作者 余旺 彭映林 郑雅杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期211-219,共9页
Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal rea... Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows: n(CaO)/n(Fe2+) 1.4:1, reaction temperature 80 ℃, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe3+ to FJ+ in the reaction solution 1.9-2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively. 展开更多
关键词 ferrous sulphate titanium dioxide magnetite concentrate CO-PRECIPITATION wet milling magnetic separation
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Study on Co-Effect of K<sub>2</sub>SO<sub>4</sub>Deposition and Low Concentration SO<sub>2</sub>on Performances of V<sub>2</sub>O<sub>5</sub>/AC Catalysts for Low Temperature SCR
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作者 Xianlong Zhang Bowen Shi +4 位作者 Xueping Wu Zhanggen Huang Zhenyu Liu Baojun Yang Cuiping Zhang 《Advances in Chemical Engineering and Science》 2011年第4期176-182,共7页
Simulated compounds were prepared by loading K2SO4 onto V2O5/AC catalysts. Study the effect of K2SO4 on V1/AC catalysts in the presence of low concentration SO2. Transient response techniques, TPD was carried out. The... Simulated compounds were prepared by loading K2SO4 onto V2O5/AC catalysts. Study the effect of K2SO4 on V1/AC catalysts in the presence of low concentration SO2. Transient response techniques, TPD was carried out. The results indicated that the DeNO activity of V1/AC catalysts was decreased seriously in the early period of operation, but the deactivation was gradually diminished with SO2 adsorption and then, it was completely eliminated. For the sulphated catalysts (saturated catalysts by sulphate), their SCR activity were free from existence of gaseous SO2. the loss of activity about 10% caused by K2SO4 was found on them. The deactivation of K2SO4 deposited catalysts was due to the decrease of adsorbed and activated NH3, or some acid sites. 展开更多
关键词 Vanadium Oxide CATALYST SCR K2SO4 DEPOSITION Deactivation sulphated CATALYST
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Extraction of molybdenum and nickel from roasted Ni-Mo ore by hydrochloric acid leaching, sulphation roasting and water leaching 被引量:2
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作者 羡鹏飞 周升帆 +2 位作者 王明玉 王学文 陈边防 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期220-226,共7页
To extract molybdenum and nickel from the roasted Ni-Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leac... To extract molybdenum and nickel from the roasted Ni-Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leaching rate of Mo and Ni. Under the optimum conditions of hydrochloric acid leaching (roasted Ni-Mo ore leached with 0.219 mL/g hydrochloric acid addition at 65 ℃ for 30 min with a L/S ratio of 3 mL/g), sulphation roasting (51.9% sulfiaric acid addition, roasting temperature 240 ℃ for 1 h), followed by leaching with the first stage hydrochloric acid leaching solution at 95 ℃ for 2 h, the leaching rates of Mo and Ni reached 95.8% and 91.3%, respectively. 展开更多
关键词 MOLYBDENUM NICKEL Ni-Mo ore hydrochloric acid leaching sulphation roasting water leaching
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Pharmacokinetics of Controlled Release and Immediate Release Morphine Sulphate Tablets after a Single Dose and Multiple Doses in Chinese Volunteers
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作者 邓艳萍 王凯 +3 位作者 刘立京 刘静雯 蔡志基 楼雅卿 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第4期39-42,共4页
The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg)... The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg) and immediate release tablets (IRMS, 20 mg). The plasma concentration of morphine was determined by GC MS. The pharmacokinetic parameters of controlled release tablets and immediate release tablets were calculated∶ C max was 19.38±3.80 and 21.27±6.21 ng/ml, t max was 2.36 ±0.37 h and 0.56±0.16 h, t 1/2β was 3.53±0.87 and 3.03±0.74 h, AUC was 145.15±17.65 and 93.08±16.65 ng/ml, respectively. The steady state plasma concentration of morphine sulphate in cancer patients after multiple doses was achieved, C max of CRMS and IRMS was 27.43±0.33 ng/ml and 22.68±0.16 ng/ml, C min of CRMS and IRMS was 19.45±1.44 ng/ml and 18.14±0.49 ng/ml, respectively. 展开更多
关键词 Controlled release morphine sulphate tablet Immediate release morphine sulphate tablet PHARMACOKINETICS Single dose Multiple doses GC MS
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Schistosoma mansoni proteins attenuate gastrointestinal motility disturbances during experimental colitis in mice 被引量:11
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作者 Nathalie E Ruyssers Benedicte Y De Winter +7 位作者 Joris G De Man Natacha D Ruyssers Ann J Van Gils Alex Loukas Mark S Pearson Joel V Weinstock Paul A Pelckmans Tom G Moreels 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第6期703-712,共10页
AIM:To investigate the therapeutic effect of Schistosoma mansoni(S.mansoni) soluble worm proteins on gastrointestinal motility disturbances during experimental colitis in mice. METHODS:Colitis was induced by intrarect... AIM:To investigate the therapeutic effect of Schistosoma mansoni(S.mansoni) soluble worm proteins on gastrointestinal motility disturbances during experimental colitis in mice. METHODS:Colitis was induced by intrarectal injection of trinitrobenzene sulphate(TNBS) and 6 h later,mice were treated ip with S.mansoni proteins.Experiments were performed 5 d after TNBS injection.Inflammationwas quantified using validated inflammation parameters. Gastric emptying and geometric center were measured to assess in vivo gastrointestinal motility.Peristaltic activity of distal colonic segments was studied in vitro using a modified Trendelenburg set-up.Cytokine profiles of T-lymphocytes isolated from the colon were determined by real time reverse transcriptase-polymerase chain reaction. RESULTS:Intracolonic injection of TNBS caused severe colitis.Treatment with S.mansoni proteins significantly ameliorated colonic inflammation after 5 d.TNBS did not affect gastric emptying but significantly decreased the geometric center and impaired colonic peristaltic activity 5 d after the induction of colitis.Treatment with S.mansoni proteins ameliorated these in vivo and in vitro motility disturbances.In addition,TNBS injection caused a downregulation of effector T cell cytokines after 5 d,whereas a S.mansoni protein effect was no longer observed at this time point. CONCLUSION:Treatment with S.mansoni proteins attenuated intestinal inflammation and ameliorated motility disturbances during murine experimental colitis. 展开更多
关键词 Schistosoma mansoni Helminth proteins COLITIS PERISTALSIS Crohn’s disease Gastrointestinal motility Trinitrobenzene sulphate
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Attenuation of dextran sodium sulphate induced colitis in matrix metalloproteinase-9 deficient mice 被引量:9
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作者 Alfredo Santana Carlos Medina +5 位作者 Maria Cristina Paz-Cabrera Federico Díaz-Gonzalez Esther Farré Antonio Salas Marek W Radomski Enrique Quintero 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第40期6464-6472,共9页
AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5... AIM: To study whether matrix metalloproteinase-9 (MMP-9) is a key factor in epithelial damage in the dextran sodium sulphate (DSS) model of colitis in mice.METHODS: MMP-9-deficient and wild-type (wt) mice were given 5% DSS in drinking water for 5 d followed by recovery up to 7 d. On d 5 and 12 after induction of colitis, gelatinases, MMP-2 and MMP-9, were measured in homogenates of colonic tissue by zymography and Western blot, whereas tissue inhibitor of metalloproteinases (TIMPs) were measured by reverse zymography. The gelatinolytic activity was also determined in supernatants of polymorphonuclear leukocytes (PMN) isolated from mice blood. Moreover, intestinal epithelial cells were stimulated with TNF-α to study whether these cells were able to produce MMPs. Finally, colonic mucosal lesions were measured by microscopic examination. RESULTS: On d 5 of colitis, the activity of MMP-9 was increased in homogenates of colonic tissues (0.24 ± 0.1 vs 21.3 ± 6.4, P < 0.05) and PMN from peripheral blood in wt (0.5 ± 0.1 vs 10.4 ± 0.7, P < 0.05), but not in MMP-9-deficient animals. The MMP-9 activity was also up-regulated by TNF-α in epithelial intestinal cells (2.5 ± 0.5 vs 14.7 ± 3.0, P < 0.05). Although colitis also led to increase of TIMP-1 activity, the MMP-9/TIMP-1 balance remained elevated. Finally, in the MMP-9-deficient colitic mice both the extent and severity of intestinal epithelialinjury were significantly attenuated when compared with wt mice. CONCLUSION: We conclude that DSS induced colitis is markedly attenuated in animals lacking MMP-9. This suggests that intestinal injury induced by DSS is modu-lated by MMP-9 and that inhibition of this gelatinase may reduce inflammation. 展开更多
关键词 Matrix metalloproteinases MMP-9-deficient Dextran sodium sulphate Inflammatory bowel disease Experimental colitis
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Effect of SO_2 on the performance of Ag-Pd/Al_2O_3 for the selective catalytic reduction of NOx with C_2H_5OH 被引量:4
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作者 XIE Shu-xia YU Yun-bo WANG Jin HE Hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期973-978,共6页
The influence of SO2 on the performance of Ag-Pd/Al2O3 for the selective catalytic reduction (SCR) of NOx with C2H5OH was investigated experimentally. The activity test results suggest that Ag-Pd/Al2O3 shows a small... The influence of SO2 on the performance of Ag-Pd/Al2O3 for the selective catalytic reduction (SCR) of NOx with C2H5OH was investigated experimentally. The activity test results suggest that Ag-Pd/Al2O3 shows a small activity loss in the presence of SO2 when using C2H5OH as a reductant. In situ DRIFTS spectra show that the activity loss originates from the formation of surface sulphate species on the Ag-Pd/Al2O3. The surface sulphate species formation inhibits the formation of nitrate, whereas hardly changes the partial oxidation of C2H5OH. Compared with the NOx reduction by C3H6, an obvious suppression of the surface sulphate species formation was observed by DRIFTS experiment when using C2H5OH as a reductant. This phenomenon reveals the better catalytic performance and strong SO2 tolerance of Ag-Pd/Al2O3-C2H50H system. 展开更多
关键词 sulphate SCR NITRATE enolic species ISOCYANATE reaction mechanism
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Beneficial effects of nutritional supplements on intestinal epithelial barrier functions in experimental colitis models in vivo 被引量:6
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作者 Hilda Vargas-Robles Karla Fabiola Castro-Ochoa +1 位作者 Alí Francisco Citalán-Madrid Michael Schnoor 《World Journal of Gastroenterology》 SCIE CAS 2019年第30期4181-4198,共18页
Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute co... Acute and chronic colitis affect a huge proportion of the population world-wide.The etiology of colitis cases can be manifold,and diet can significantly affect onset and outcome of colitis.While many forms of acute colitis are easily treatable,chronic forms of colitis such as ulcerative colitis and Crohn’s disease(summarized as inflammatory bowel diseases)are multifactorial with poorly understood pathogenesis.Inflammatory bowel diseases are characterized by exacerbated immune responses causing epithelial dysfunction and bacterial translocation.There is no cure and therapies aim at reducing inflammation and restoring intestinal barrier function.Unfortunately,most drugs can have severe side effects.Changes in diet and inclusion of nutritional supplements have been extensively studied in cell culture and animal models,and some supplements have shown promising results in clinical studies.Most of these nutritional supplements including vitamins,fatty acids and phytochemicals reduce oxidative stress and inflammation and have shown beneficial effects during experimental colitis in rodents induced by dextran sulphate sodium or 2,4,6-trinitrobenzene sulfonic acid,which remain the gold standard in pre-clinical colitis research.Here,we summarize the mechanisms through which such nutritional supplements contribute to epithelial barrier stabilization. 展开更多
关键词 Colitis DEXTRAN sulphate sodium 2 4 6-trinitrobenzene sulfonic acid Tight JUNCTION Adherens JUNCTION PHYTOCHEMICALS BUTYRATE VITAMINS Short chain fatty acids MICRONUTRIENTS
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Carboniferous Mixed Terrigenous Clastic, Carbonate and Sulphate Sediments in the Bachu Area, Xinjiang 被引量:4
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作者 XIAO Chuantao PAN Yuntang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第3期341-347,共7页
The Carboniferous system in the Xiaohaizi area, Bachu County, Xinjiang Uygur Autonomous Region, composed of typical mixed terrigenous clastic, carbonate and sulphate sediments, was mainly deposited in the tidal flat a... The Carboniferous system in the Xiaohaizi area, Bachu County, Xinjiang Uygur Autonomous Region, composed of typical mixed terrigenous clastic, carbonate and sulphate sediments, was mainly deposited in the tidal flat and lagoon environments. The mixed sediments occur as the following eleven types: 1. limestone intercalated with siltstone; 2. interbeds of shale and limestone; 3. gypsolyte interbedded with limestone; 4. gypsolyte intercalated with siltstone; 5. gypsolyte interbedded with shale; 6. gypsolyte intercalated with siltstone, limestone and dolomite; 7. siltstone interbedded with gypsolyte and limestone; 8. terrigenous detritus scattered in carbonate matrix; 9. carbonate as cement in clastic rocks; 10. mixed sediments of carbonate and terrigenous mud; 11. mixed sediments of carbonate grains with terrigenous sand. Based on the analysis of the dynamic mechanism of mixed sediments, it is believed that these types of mixed sediments in the study area were controlled by climate, sea level change and sources of sediments. 展开更多
关键词 terrigenous DETRITUS CARBONATE sulphate (gypsolyte) MIXED SEDIMENTS CARBONIFEROUS strata Xinjiang.
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Extraction of aluminium as aluminium sulphate from thermal power plant fly ashes 被引量:5
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作者 Seoul SANGITA Niva NAYAK Chitta Ranjan PA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2082-2089,共8页
Valuable metal extraction technology from thermal power plant fly ash is limited.In the present study,aluminium is extracted from fly ash as highly pure aluminium sulphate(>99.0%)by leaching with sulphuric acid,fol... Valuable metal extraction technology from thermal power plant fly ash is limited.In the present study,aluminium is extracted from fly ash as highly pure aluminium sulphate(>99.0%)by leaching with sulphuric acid,followed by pre-concentration and successive crystallization.Two types of fly ashes from different sources,i.e.,Talcher Thermal Power Station(TTPS)and Vedanta Aluminium Company Limited(VAL)were chosen for comparative study on the extraction of aluminium as aluminium sulphate.The product is characterized by powder X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR)and thermogravimetric analysis(TGA).Purity of aluminium sulphate was also investigated by inductively coupled plasma?optical emission spectrometry(ICP?OES).The extraction efficiency of aluminium depends on the varied solid-to-liquid ratio(fly ash:18mol/L H2SO4,g/mL)and particle size of fly ashes.Physico-chemical analysis indicates that the obtained product is Al2(SO4)3·18H2O,having low iron content(0.08%). 展开更多
关键词 fly ash sulphuric acid aluminium sulphate LEACHING solid-to-liquid ratio particle size
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