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颈椎病、腰椎间盘突出症与自由基损伤的探讨 被引量:55
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作者 张向阳 马玉玲 杨际平 《颈腰痛杂志》 1995年第4期202-203,228,共3页
应用TBA比色法和黄嘌呤氧化酶法测定了颈椎病、腰椎间盘突出症。中医治疗前后血清LPO含量和SOD活性,及应用大剂量VitC抗自由基治疗的疗效观察。结果表明:颈椎病、腰椎间盘突出症病人血清LPO明显高于对照组(P<0.... 应用TBA比色法和黄嘌呤氧化酶法测定了颈椎病、腰椎间盘突出症。中医治疗前后血清LPO含量和SOD活性,及应用大剂量VitC抗自由基治疗的疗效观察。结果表明:颈椎病、腰椎间盘突出症病人血清LPO明显高于对照组(P<0.01),而血清SOD活力却比对照组明显降低(P<0.01)。中医治疗后同治疗前相比较,血清LPO明显下降(P<0.01),血清SOD活力有所提高(P<0.05),但是,血清LPO,或从LPO/SOD比值上看仍没有恢复到正常人水平。而使用VitC治疗组有效率明显高于非VitC治疗组。提示:颈椎病、腰椎间盘突出症的发病与自由基损伤有关。清除自由基、提高SOD活力可能是中医治疗颈椎病,腰椎间盘突出症的机制之一。 展开更多
关键词 颈椎病 椎间盘突出 自由基
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城市公园免费开放对游客感知价值维度的影响及效应分析——以南京中山陵为例 被引量:59
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作者 周玮 黄震方 +2 位作者 殷红卫 吴丽敏 曹芳东 《地理研究》 CSSCI CSCD 北大核心 2012年第5期873-884,共12页
基于城市公园免费开放的视角,选取南京中山陵作为研究个案,运用SPSS18.0和AMOS18.0分析软件,通过探索性和验证性因素分析,构建了游客感知价值维度分析模型。研究显示:游客对免费开放中山陵存在五维感知价值,且呈现出感知价格→休闲价值... 基于城市公园免费开放的视角,选取南京中山陵作为研究个案,运用SPSS18.0和AMOS18.0分析软件,通过探索性和验证性因素分析,构建了游客感知价值维度分析模型。研究显示:游客对免费开放中山陵存在五维感知价值,且呈现出感知价格→休闲价值→环境价值→服务价值→文化价值逐步递减的分异特征;由此探究游客感知价值维度分异的作用机制,衍生出城市公园免费开放的效应分析,其中公益福利效应和休闲游憩效应呈现积极的正向发展态势,而生态环境效应、景区服务效应与文化内生效应的发挥则相对滞后。在倡导"以人为本"、关注民生休闲的大众旅游时代,免费开放城市公园在增强城市开放空间优质属性和综合竞争力的同时,其与城市旅游的耦合协调及可持续发展将面临新的挑战。 展开更多
关键词 城市公园 免费开放 游客感知价值 南京中山陵
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Berberine reverses free-fatty-acid-induced insulin resistance in 3T3-L1 adipocytes through targeting IKKβ 被引量:52
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作者 Ping Yi Fu-Er Lu +3 位作者 Li-Jun Xu Guang Chen Hui Dong Kai-Fu Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第6期876-883,共8页
AIM: To investigate the effects and molecular mechanisms of berberine on improving insulin resistance induced by free fatty acids (FFAs) in 3T3-L1 adipocytes. METHODS: The model of insulin resistance in 3T3-L1 adipocy... AIM: To investigate the effects and molecular mechanisms of berberine on improving insulin resistance induced by free fatty acids (FFAs) in 3T3-L1 adipocytes. METHODS: The model of insulin resistance in 3T3-L1 adipocytes was established by adding palmic acid (0.5 mmol/L) to the culture medium. Berberine treatment was performed at the same time. Glucose uptake rate was determined by the 2-deoxy-[3H]-D-glucose method. The levels of IkB kinase beta (IKKβ) Ser181 phosphorylation, insulin receptor substrate-1(IRS-1) Ser307 phosphorylation, expression of IKKβ, IRS-1, nuclear transcription factor kappaB p65 (NF-κB p65), phosphatidylinositol-3-kinase p85 (PI-3K p85) and glucose transporter 4 (GLUT4) proteins were detected by Western blotting. The distribution of NF-κB p65 proteins inside the adipocytes was observed through confocal laser scanning microscopy (CLSM). RESULTS: After the intervention of palmic acid for 24 h, the insulin-stimulated glucose transport in 3T3-L1 adipocytes was inhibited by 67%. Meanwhile, the expression of IRS-1 and PI-3K p85 protein was reduced, while the levels of IKKβ Ser181 and IRS-1 Ser307 phosphorylation, and nuclear translocation of NF-κB p65 protein were increased. However, the above indexes, which indicated the existence of insulin resistance, were reversed by berberine although the expression of GLUT4, IKKβ and total NF-κB p65 protein were not changed during this study. CONCLUSION: Insulin resistance induced by FFAs in 3T3-L1 adipocytes can be improved by berberine. Berberine reversed free-fatty-acid-induced insulin resistance in 3T3-L1 adipocytes through targeting IKKβ. 展开更多
关键词 BERBERINE Insulin resistance IkB kinase beta free fatty acid
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Decrease-radix design principle for carrying/borrowing free multi-valued and application in ternary optical computer 被引量:41
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作者 YAN JunYong JIN Yi ZUO KaiZhong 《Science in China(Series F)》 2008年第10期1415-1426,共12页
In this paper a new theory referred to as the decrease-radix design (DRD) is proposed, which is found in the research of logic units of ternary (tri-valued) optical computer. Based on the theory proposed, the prin... In this paper a new theory referred to as the decrease-radix design (DRD) is proposed, which is found in the research of logic units of ternary (tri-valued) optical computer. Based on the theory proposed, the principles and the regulations of the DRD for making operation units of multi-valued operation with carrying/borrowing free are also presented. The research work has come to the following important conclusion: let D be a special state contained in n physical informative states, then one may figure out any multi-valued processors within n^(n×n) carrying/borrowing free n-valued units by the composition some of n×n×(n-1) simplest basic operating units according to the regulations of DRD proposed in this paper. The detailed systematic way of our design regulations is highlighted step by step in the paper with an example of design of a tri-valued logic optical operating unit. The real architecture, the procedure, and the experimental results of our sample in tri-valued logic operating unit are given. Finally, a re-constructible model of ternary logical optical processor is introduced. The theory proposed in the paper has laid down a solid foundation for the design of re-constructible carrying/borrowing free operating units in ternary optical computers and can be widely used as the designing reference in a variety of multi-valued logic operating units. 展开更多
关键词 carrying/borrowing free operating units decrease-radix design re-constructible ternary optical computer
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Formation and Water Stability of Aggregates in Red Soils as Affected by Organic Matter 被引量:39
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作者 ZHANG MINGKUI HE ZHENLI +1 位作者 CHEN GUOCHAO HUANG CHANGYONGI andM. J. WILSON ̄2( ̄1DePartment of Land Use and Applied Chemistry, Zhejiang Agricultural University, Hangzhou 31O029(China))( ̄2Soils and Soil Microbiology Division, Macaulay Land Use Research Inst 《Pedosphere》 SCIE CAS CSCD 1996年第1期39-45,共7页
The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studi... The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studied. The results showed that the water stability of soil aggregates declined with increasing size, especially for the low organic matter soils. Organic matter plays a key role in the formation of water-stable soil aggregates. The larger the soil aggregate size, the greater the impact of organic matter on the water stability of soil aggregates. Removal of organic matter markedly disintegrated the large water-stable aggregates (> 2.0 mm) and increased the small ones (< 0.25-0.smm) to some extent, whereas removal of free iron(aluminium) oxides considerably destroyed aggregates of all sizes, especially the < 0.25-0.5 mm classes. The contents of organic matter in water-stable aggregates increased with aggregate sizes. It is concluded from this study that small water-stable aggregates (< 0.25-0.5 mm) were chiefly cemented by Fe and Al oxides whilst the large ones (> 2.0 mm) were mainly glued up by organic matter. Both free oxides and organic matter contribute to the formation and water stability of aggregates in red soils. 展开更多
关键词 AGGREGATE free oxides organic matter red soil water stability
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Current progress of China’s free ART program 被引量:40
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作者 Jennifer PAN 《Cell Research》 SCIE CAS CSCD 2005年第11期877-882,共6页
China’s Free ART Program was initiated in 2002 as an emergency response to save and improve the lives of AIDS patients living mainly in impoverished rural regions of central China. With little experience in HIV/AIDS ... China’s Free ART Program was initiated in 2002 as an emergency response to save and improve the lives of AIDS patients living mainly in impoverished rural regions of central China. With little experience in HIV/AIDS treatment and care and resource limitations, China’s efforts to provide widespread access to free antiretroviral therapy has been a process fraught with difficulty. However, the Free ART Program is progressing from an emergency response to a standardized treatment and care system. The development of national guidelines, training programs, a laboratory sup- port network, a national patient database, programs for special populations such as children and patients living with co- infections, and operational research has improved the scope and quality of the free treatment program. As of June 30, 2005, a total of 19,456 patients in 28 provinces, autonomous regions, and special municipalities had received free ART. Challenges stemming from the nature of China’s health system and patient population persist, but with strong govern- ment support and a diverse set of resources, China has the capacity to overcome these challenges and to provide nationwide access to high quality treatment and care. 展开更多
关键词 human immunodeficiency virus acquired immune deficiency syndrome China antiretroviral therapy free ART program treatment and care
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Relationship between Acute Organophosphorus Pesticide Poisoning and Damages Induced by Free Radicals 被引量:29
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作者 ZHOU JUN-FU XU GEN-BO FANG WEI-JUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第2期177-186,共10页
关键词 Organophosphorus pesticide poisoning free radicals Lipoperoxides Nitric oxide ANTIOXIDANTS Antioxidases
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Effect of selected fungi on the reduction of gossypol levels and nutritional value during solid substrate fermentation of cottonseed meal 被引量:33
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作者 ZHANG Wen-ju XU Zi-rong +1 位作者 SUN Jian-yi YANG Xia 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第9期690-695,共6页
The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fen'aentation of cottonseed meal (CSM). S... The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fen'aentation of cottonseed meal (CSM). Six groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. capsuligena ZD- 1, C. tropicalis ZD-3, S. cerevisae ZD-5, A. terricola ZD-6, A. oryzae ZD-7, or A. niger ZD-8. One not inoculated group (substrate) was used as a control. Levels of initial and final free gossypol (FG), crude protein (CP), amino acids (AA) and in vitro digestibility were assayed. The experiment was done in triplicate. The experimental results indicated that microbial fermentation could greatly decrease (P〈0.05) FG levels in CSM. The detoxification efficiency differed between the species of microorganisms applied. From the perspective of reducing CSM potential toxicity, C. tropicalis ZD-3 was most successful followed by S. cerevisae ZD-5 and A. niger ZD-8. They could reduce FG levels of CSM to 29.8, 63.07 and 81.50 mg/kg based on DM (dry matter), respectively, and their detoxification rates were 94.57%, 88.51% and 85.16%, respectively. If crude protein, amino acids content and their in vitro digestibility were also taken into account, Aniger ZD-8 may be the best choice. The CP content of CSM substrate fermented by C. tropicalis ZD-3 and A. niger ZD-8 were improved by 10.76% and 22.24%; the TAA (total amino acids) contents were increased by 7.06% and 11.46%, and the EAA (essential amino acids) were raised by 7.77% and 12.64%, respectively. Especially, the levels of methionine, lysine and threonine were improved greatly (P〈0.05). The in vitro CP digestibility of CSM fermented by C. tropicalis ZD-3 and A. niger ZD-8 was improved by 13.42% and 18.22%, the TAA were increased by 17.75% and 22.88%, and the EAA by 16.61% and 21.01%, respectively. In addition, the in vitro digestibility of methionine, lysine and threonine was also improved grea 展开更多
关键词 FUNGI free gossypol Solid substrate fermentation Cottonseed meal DETOXIFICATION Nutritional value
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Atorvastatin protects against cerebral ischemia/ reperfusion injury through anti-inflammatory and antioxidant effects 被引量:29
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作者 Qiuyun Tu Hui Cao +2 位作者 Wei Zhong Binrong Ding Xiangqi Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第3期268-275,共8页
In addition to its lipid-lowering effect, atorvastatin exerts anti-inflammatory and antioxidant effects as well. In this study, we hypothesized that atorvastatin could protect against cerebral isch-emia/reperfusion in... In addition to its lipid-lowering effect, atorvastatin exerts anti-inflammatory and antioxidant effects as well. In this study, we hypothesized that atorvastatin could protect against cerebral isch-emia/reperfusion injury. The middle cerebral artery ischemia/reperfusion model was established, and atorvastatin, 6.5 mg/kg, was administered by gavage. We found that, after cerebral ischemia/ reperfusion injury, levels of the inflammation-related factors E-selectin and myeloperoxidase were upregulated, the oxidative stress-related marker malondialdehyde was increased, and super- oxide dismutase activity was decreased in the ischemic cerebral cortex. Atorvastatin pretreatment significantly inhibited these changes. Our findings indicate that atorvastatin protects against ce-rebral ischemia/reperfusion injury through anti-inflammatory and antioxidant effects. 展开更多
关键词 nerve regeneration brain injury cerebral ischemia/reperfusion ATORVASTATIN E-SELECTIN MYELOPEROXIDASE superoxide dismutase MALONDIALDEHYDE inflammation free radicals blood-brainbarrier stroke NSFC grant neural regeneration
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Abundance and biomass of meiobenthos in the spawning ground of anchovy (Engraulis japanicus) in the southern Huanghai Sea 被引量:29
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作者 LIUXiaoshou ZHANGZhinan HUANGYong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第3期94-104,共11页
A grid of 22 stations, giving a broad coverage of the spawning ground of anchovy in the southern Huanghai Sea was selected. Undis- turbed sediments were taken from sampling stations during the cruise in June 2003. The... A grid of 22 stations, giving a broad coverage of the spawning ground of anchovy in the southern Huanghai Sea was selected. Undis- turbed sediments were taken from sampling stations during the cruise in June 2003. The average abundance of meiofauna is (1 584± 686) ind./10cm2, with corresponding biomass (dwt) of (1 086±425)!μg/10cm2. The pattern of abundance of meiofauna is similar to the pattern of biomass. There are 65.88% meiofauna in 0 ̄2 cm sediments, 27.66% in 2 ̄5 cm sediments and 6.47% in 5 ̄8 cm sediments. The Spearman correlation analysis between meiofauna and environmental factors shows that abundance of meiofauna, free living ma- rine nematodes, benthic copepods has significant positive correlations with Chl-a. And the abundance of copepods has significant posi- tive correlations with several factors such as Chl-a, Pha-a, Chl-a plus Pha-a and organic matter. A total of 18 meiofauna groups are i- dentified. Nematode is the most dominant group, average abundance (1 404±670) ind/10cm2, accounting for 88.65%, and the follow- ing groups are also important: benthic copepods (5.48%), kinorhyncha (1.26%), polychaeta (1.07%). By biomass, dominant groups are nematodes (51.72%), polychaeta (21.84%), copepods (14.87%), ostracoda (4.92%), kinorhyncha (3.67%). A total of 90 species of ne- matodes are identified. The species composition of nematodes is listed based on selected two stations 7794 (coastal area) and 10694 (cold water mass in deep waters). 展开更多
关键词 meiofauna free living marine nematodes benthic copepods ABUNDANCE BIOMASS southern Huanghai Sea
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北美自由贸易区的经验及对我国的启示 被引量:23
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作者 沈四宝 王秉乾 《法学杂志》 北大核心 2005年第6期101-104,共4页
关键词 北美自由贸易区 中国一东盟自由贸易区 发展中国家 发达国家 TRADE free 周年纪念 贸易组织 经济集团 经济情况
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Protective effect of ascorbic acid on cyclophosphamide induced testicular gametogenic and androgenic disorders in male rats 被引量:28
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作者 Ujjal Baran Das Mousumi Mallick +1 位作者 Jogendra Mohan Debnath Debidas Ghosh 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第3期201-207,共7页
Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate th... Aim:To study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid.Methods:The testicular△^(5),3β-hydroxysteroid dehydrogenase(HSD),17β-HSD,peroxidase and catalase activities along with the levels of malondialdehyde(MDA)and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress.The plasma testosterone(T)level was measured by immunoassay.Various germ cells at stageⅦof spermatogenic cycle were quantified from testicular stained sections.Results:Cyclophosphamide treatment results in a significant inhibition in the testicular△^(5),3β-HSD and 17β-HSD activities,a decrease in plasma T level and a diminution in the counts of various germ cells.Moreover,this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis.All these changes were reversed by ascorbic acid co-administration.Conclusion:Cyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration. 展开更多
关键词 CYCLOPHOSPHAMIDE ANDROGENESIS GAMETOGENESIS oxidative stress free radicals ascorbic acid CATALASE PEROXIDASE testosterone
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Comparative study of MPS method and level-set method for sloshing flows 被引量:28
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作者 张雨新 万德成 HINO Takanori 《Journal of Hydrodynamics》 SCIE EI CSCD 2014年第4期577-585,共9页
This paper presents a comparative study of a meshless level-set method in the simulation of sloshing flows. The numerical moving particle semi-implicit (MPS) method and a grid based schemes of the MPS and level-set ... This paper presents a comparative study of a meshless level-set method in the simulation of sloshing flows. The numerical moving particle semi-implicit (MPS) method and a grid based schemes of the MPS and level-set methods are outlined and two violent sloshing cases are considered. The computed results are compared with the corresponding experimental data for validation. The impact pressure and the deformations of free surface induced by sloshing are comparatively analyzed, and are in good agreement with experimental ones. Results show that both the MPS and level-set methods are good tools for simulation of violent sloshing flows. However, the second pressure peaks as well as breaking and splashing of free surface by the MPS method are captured better than by the level-set method. 展开更多
关键词 moving particle semi-implicit (MPS) method level-set method liquid sloshing impact pressure free surface
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Collision free 4D path planning for multiple UAVs based on spatial refined voting mechanism and PSO approach 被引量:25
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作者 Yang LIU Xuejun ZHANG +1 位作者 Yu ZHANG Xiangmin GUAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第6期1504-1519,共16页
In this paper, a four-dimensional coordinated path planning algorithm for multiple UAVs is proposed, in which time variable is taken into account for each UAV as well as collision free and obstacle avoidance. A Spatia... In this paper, a four-dimensional coordinated path planning algorithm for multiple UAVs is proposed, in which time variable is taken into account for each UAV as well as collision free and obstacle avoidance. A Spatial Refined Voting Mechanism(SRVM) is designed for standard Particle Swarm Optimization(PSO) to overcome the defects of local optimal and slow convergence.For each generation candidate particle positions are recorded and an adaptive cube is formed with own adaptive side length to indicate occupied regions. Then space voting begins and is sorted based on voting results, whose centers with bigger voting counts are seen as sub-optimal positions. The average of all particles of corresponding dimensions are calculated as the refined solutions. A time coordination method is developed by generating specified candidate paths for every UAV, making them arrive the same destination with the same time consumption. A spatial-temporal collision avoidance technique is introduced to make collision free. Distance to destination is constructed to improve the searching accuracy and velocity of particles. In addition, the objective function is redesigned by considering the obstacle and threat avoidance, Estimated Time of Arrival(ETA), separation maintenance and UAV self-constraints. Experimental results prove the effectiveness and efficiency of the algorithm. 展开更多
关键词 4D path planning Collision free Multiple UAVS OBSTACLE AVOIDANCE Particle SWARM optimization SPATIAL refined VOTING mechanism
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MODELING UNCONFINED SEEPAGE FLOW USING THREE-DIMENSIONAL NUMERICAL MANIFOLD METHOD 被引量:25
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作者 JIANG Qing-hui DENG Shu-shen +1 位作者 ZHOU Chuang-bing LU Wen-bo 《Journal of Hydrodynamics》 SCIE EI CSCD 2010年第4期554-561,共8页
Three-dimensional numerical manifold method for unconfined seepage analysis is proposed in this article.By constructing hydraulic potential functions of the manifold element,the element conductivity matrix and the glo... Three-dimensional numerical manifold method for unconfined seepage analysis is proposed in this article.By constructing hydraulic potential functions of the manifold element,the element conductivity matrix and the global simultaneous equations for unconfined seepage analysis are derived in detail.The algorithm of locating the free surface and the formula for seepage forces are also given.Three-dimensional manifold method employs the tetrahedral mathematical meshes to cover the whole material volume.In the iterative process for locating the free surface,the manifold method can achieve an accurate seepage analysis of the saturated domain below the free surface with mathematical meshes unchanged.Since the shape of manifold elements can be arbitrary,the disadvantage of changing the permeability of transitional elements cut by the free surface in the conventional Finite Element Method(FEM) is removed,and the accuracy of locating the free surface can be ensured.Furthermore,the seepage force acting on the transitional elements can be accurately calculated by the simplex integration.Numerical results for a typical example demonstrate the validity of the proposed method. 展开更多
关键词 three-dimensional seepage numerical manifold method free surface mathematical mesh manifold element
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EFFECTS OF GINSENOSIDE Rb1 AND Rg1 ON SYNAPTOSOMAL FREE CALCIUM LEVEL, ATPase AND CALMODULIN IN RAT HIPPOCAMPUS 被引量:21
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作者 刘忞 张均田 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第7期66-69,共4页
Calcium homeostasis in synaptosomes is altered during aging. The intrasynaptomal free calcium concentration ([Ca2+]i) was determined in 3- and 24-month-old rats treated with or without Rbl and Rgl. As expected, the [C... Calcium homeostasis in synaptosomes is altered during aging. The intrasynaptomal free calcium concentration ([Ca2+]i) was determined in 3- and 24-month-old rats treated with or without Rbl and Rgl. As expected, the [Ca2-]i level increased with age. Treatment with Rbl and Rgl elicited an obvious decrease of [Ca2+]i content, especially in aged rates. In addition, Rbl and Rgl significantly stimulated the activity of Na+, K+-ATPase while Rbl inhibited the activity of Ca2+, Mg2--ATPase arid calmodulin. In view of the close relationship of [Ca2-]i level with aging, the changes of [Ca2+]i induced by Rbl and Rgl, as shown by our results, might provide an explanation of the mechanisms of their antiaging function. 展开更多
关键词 ATPase AND CALMODULIN IN RAT HIPPOCAMPUS In EFFECTS OF GINSENOSIDE Rb1 AND Rg1 ON SYNAPTOSOMAL free CALCIUM LEVEL
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EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FREE SURFACE VORTEX 被引量:24
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作者 LI Hai-feng CHEN Hong-xun +1 位作者 MA Zheng ZHOU Yi 《Journal of Hydrodynamics》 SCIE EI CSCD 2008年第4期485-491,共7页
An experimental model was set up to investigate the formation and evolution of the free surface vortex. A Particle Image Velocimetry (PIV) was used to measure the free surface vortex flow field at different developm... An experimental model was set up to investigate the formation and evolution of the free surface vortex. A Particle Image Velocimetry (PIV) was used to measure the free surface vortex flow field at different development stages. Flow visualization was used to locate the vortex position and find its structure. Empirical formulas about the critical submergence and the whole field structure were obtained. It is found that the tangential velocity distribution is similar to that of the Rankine vortex and the radial velocity changes little in the vortex functional scope. Vortex starts from the free surface and gradually intensifies to air entrainment vortex. The vortex core moves during the formation and evolution of the free surface vortex. Based on the experimental model, the vortex position and structure were predicted by numerical simulation combined with a vortex model and compared with that of the experiments, which shows satisfactory agreement. 展开更多
关键词 free surface vortex Particle Image Velocimetry (PIV) numerical simulation rankine vortex
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Neighbor sum distinguishing total colorings of K4-minor free graphs 被引量:24
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作者 Hualong LI Bingqiang LIU Guanghui WANG 《Frontiers of Mathematics in China》 SCIE CSCD 2013年第6期1351-1366,共16页
A total [k]-coloring of a graph G is a mapping φ: V(G) U E(G) →{1, 2, ..., k} such that any two adjacent elements in V(G)UE(G) receive different colors. Let f(v) denote the sum of the colors of a vertex v... A total [k]-coloring of a graph G is a mapping φ: V(G) U E(G) →{1, 2, ..., k} such that any two adjacent elements in V(G)UE(G) receive different colors. Let f(v) denote the sum of the colors of a vertex v and the colors of all incident edges of v. A total [k]-neighbor sum distinguishing-coloring of G is a total [k]-coloring of G such that for each edge uv E E(G), f(u) ≠ f(v). By tt [G, Xsd( J, we denote the smallest value k in such a coloring of G. Pilniak and Woniak conjectured X'sd(G) 〈 A(G) + 3 for any simple graph with maximum degree A(G). This conjecture has been proved for complete graphs, cycles, bipartite graphs, and subcubic graphs. In this paper, we prove that it also holds for Ka-minor free graphs. Furthermore, we show that if G is a Ka-minor flee graph with A(G) 〉 4, then " Xnsd(G) 〈 A(G) + 2. The bound A(G) + 2 is sharp. 展开更多
关键词 K4-minor free graph neighbor sum distinguishing (nsd)
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Pathogenesis of pancreatic encephalopathy in severe acute pancreatitis 被引量:24
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作者 Zhang, Xi-Ping Tian, Hua 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第2期134-140,共7页
BACKGROUND: Pancreatic encephalopathy (PE) is a serious complication of severe acute pancreatitis (SAP). In recent years, more and more PE cases have been reported worldwide, and the onset PE in the early stage was re... BACKGROUND: Pancreatic encephalopathy (PE) is a serious complication of severe acute pancreatitis (SAP). In recent years, more and more PE cases have been reported worldwide, and the onset PE in the early stage was regarded as a poor prognosis sign of SAP, but the pathogenesis of PE in SAP still has not been clarified in the past decade. The purpose of this review is to elucidate the possible pathogenesis of PE in SAP. DATA SOURCES: The English-language literature concerning PE in this review came from the Database of MEDLINE (period of 1991-2005), and the keywords of severe acute pancreatitis and pancreatic encephalopathy were used in the searching. RESULTS: Many factors were involved in the pathogenesis of PE in SAP. Pancreatin activation, excessive release of cytokines and oxygen free radicals, microcirculation abnormalities of hemodynamic disturbance, ET-1/NO ratio, hypoxemia, bacterial infection, water and electrolyte imbalance, and vitamin B1 deficiency participated in the development of PE in SAP. CONCLUSIONS: The pathogenesis of PE in SAP has not yet been fully understood. The development of PE in SAP may be a multi-factor process. To find out the possible inducing factor is essential to the clinical management of PE in SAP. 展开更多
关键词 severe acute pancreatitis pancreatic encephalopathy PATHOGENESIS MICROCIRCULATION CYTOKINES phospholipase A(2) oxygen free radicals vitamin B1 deficiency
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Mechanism of Anti-β-adrenoceptor Antibody Mediated Myocardial Damage in Dilated Cardiomyopathy 被引量:21
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作者 廖玉华 程龙献 +5 位作者 涂源淑 张金枝 董继华 李淑莉 田元 彭又红 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1997年第1期5-8,共4页
Antibodies against &-adrenoceptor can be detected in serum of patients with dilated cardiomyopathy (DCM), which have 5-agonist-like activity, and induce a positive chronotropic effect on cardiac myocytes by its pe... Antibodies against &-adrenoceptor can be detected in serum of patients with dilated cardiomyopathy (DCM), which have 5-agonist-like activity, and induce a positive chronotropic effect on cardiac myocytes by its persistence at full strength. Effects of the antibodies against Padrenoceptor from sera of patients with DCM on myocardial cytotoxicity and cytoplasmic free Ca2+-concentration (LCa2+ji) were observed in the cultured single layer SD rat ventricular cells by using the cytotoxicity assay and fluorescent Ca2+- indicat0r fura-2/AM. The positive sera of the anti-&adrenoceptor antibodies from patients with DCM markedly enhanced myocardial [Ca2+]i. Betaloc, a 5, -receptor blocker, might inhibit the increase of the antibody-mediated myocardial [Ca2+]i, and the sera from healthy donors had no effect on myocardial [Ca2+]i,. Our results suggest that the anti-β-adrenoceptor antibody might increase myocardial [Ca2+]i, and result in myocardial damage. The antibodies might activate receptor-gating Ca2+-channel, thereby causing myocardial [Ca2+]i, rise and calcium overload. Early use of betaloc is recommended in the treatment of dilated cardiomyopathy. 展开更多
关键词 ANTIBODIES Β-ADRENOCEPTOR cytoplasmic free calcium FURA-2/AM dilated cardiomyopathy
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