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A review of regional groundwater flow modeling 被引量:2
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作者 Yangxiao Zhou Wenpeng Li 《Geoscience Frontiers》 SCIE CAS 2011年第2期205-214,共10页
Significant advances in regional groundwater flow modeling have been driven by the demand to predict regional impacts of human inferences on groundwater systems and associated environment. The wide availability of pow... Significant advances in regional groundwater flow modeling have been driven by the demand to predict regional impacts of human inferences on groundwater systems and associated environment. The wide availability of powerful computers, user friendly modeling systems and GIS stimulates an exponential growth of regional groundwater modeling. Large scale transient groundwater models have been built to analyze regional flow systems, to simulate water budget components changes, and to optimize groundwater develop- ment scenarios. This paper reviews the historical development of regional groundwater modeling. Examples of Death Valley and Great Artesian Basin transient groundwater models are introduced to show the application of large scale regional groundwater flow models. Specific methodologies for regional groundwater flow modeling are descried and special issues in regional groundwater flow modeling are discussed. 展开更多
关键词 regional flow system Modeling methodology Modeling issues
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GACNet: A Generative Adversarial Capsule Network for Regional Epitaxial Traffic Flow Prediction 被引量:2
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作者 Jinyuan Li Hao Li +3 位作者 Guorong Cui Yan Kang Yang Hu Yingnan Zhou 《Computers, Materials & Continua》 SCIE EI 2020年第8期925-940,共16页
With continuous urbanization,cities are undergoing a sharp expansion within the regional space.Due to the high cost,the prediction of regional traffic flow is more difficult to extend to entire urban areas.To address ... With continuous urbanization,cities are undergoing a sharp expansion within the regional space.Due to the high cost,the prediction of regional traffic flow is more difficult to extend to entire urban areas.To address this challenging problem,we present a new deep learning architecture for regional epitaxial traffic flow prediction called GACNet,which predicts traffic flow of surrounding areas based on inflow and outflow information in central area.The method is data-driven,and the spatial relationship of traffic flow is characterized by dynamically transforming traffic information into images through a two-dimensional matrix.We introduce adversarial training to improve performance of prediction and enhance the robustness.The generator mainly consists of two parts:abstract traffic feature extraction in the central region and traffic prediction in the extended region.In particular,the feature extraction part captures nonlinear spatial dependence using gated convolution,and replaces the maximum pooling operation with dynamic routing,finally aggregates multidimensional information in capsule form.The effectiveness of the method is evaluated using traffic flow datasets for two real traffic networks:Beijing and New York.Experiments on highly challenging datasets show that our method performs well for this task. 展开更多
关键词 regional traffic flow adversarial training feature extraction nonlinear spatial dependence dynamic routing
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Study on regional material flow analysis of Chengyang District in Qingdao 被引量:5
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作者 Zhou Zhenfeng Sun Yinglan Wang Jun 《Ecological Economy》 2006年第1期89-98,共10页
Base on the framework of material flow analsis (MFA) proposed by Eurostat, this paper collected related data and conducted a regional MFA for the Chengyang Districgt in Qingdao. The indicators such as Direct Materia... Base on the framework of material flow analsis (MFA) proposed by Eurostat, this paper collected related data and conducted a regional MFA for the Chengyang Districgt in Qingdao. The indicators such as Direct Material Input(DMI), Direct Material Consumption (DMC) and Exports are calculated or estimated for the period of year 1995 through 2004. Several derivable iudicators defining direct material productivity and material intenstiy are also evaluated and some valuable conclusions were drawn. DMI in absolute number increased from about 1645.9 kilotons in 1995to about 8052.5 kilotons in 2004. Imports contribute to about 47 to 69% of DMI, and the biggest component of imports is fossil fuel that approximatley accounts far 50% of imnports. DMI per capita of Chengyang District increased rapidly and reached 17. 4 tons in 2004. Compared with other five economies studied by WRI, material consumption intensity of Chengyang District is significantly lower than developed countries, which indicates that Chengyang District is still in a development stage The direct material productivity (actual GDP per DMI) increased 59.1% from 1995 to 2004 and has been higher than either of stadies in China, which indicates efficiency of resources utilization has improved obviously in Chengyang District. But there was significant increase in material input in the last decade, which shows that rapid increase of economy is highly dependent on requirement and consumption of natural resources. Therefore, in order to promote the sustainahility, it is essential to develop circular economy and improve utilization efficiency of resources. 展开更多
关键词 regional material flow analysis Direct matertal input (DMI) Dtrect material consumption (DMC) Direct material productivity Sustainable development
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Effectiveness analysis of the prediction of regional debris flow susceptibility in post-earthquake and drought site
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作者 CHEN Ning-sheng ZHANG Yong +5 位作者 TIAN Shu-feng DENG Ming-feng WANG Tao LIU Li-hong LIU Mei HU Gui-sheng 《Journal of Mountain Science》 SCIE CSCD 2020年第2期329-339,共11页
Debris-flow disasters occurred frequently after the Mw 8.0 Wenchuan earthquake on 12 May 2008 in Sichuan Province, China. Based on historical accounts of debris-flow disaster events, it found that debris flow occurren... Debris-flow disasters occurred frequently after the Mw 8.0 Wenchuan earthquake on 12 May 2008 in Sichuan Province, China. Based on historical accounts of debris-flow disaster events, it found that debris flow occurrence is closely related to the impact of earthquakes and droughts, because earthquakedrought activities can increase the loose solid materials, which can transform into debris flows under the effect of rainstorms. Based on the analysis of historical earthquake activity(frequency, magnitude and location), drought indexes and the trend of climate change(amount of rainfall), a prediction method was established, and the regional debris flow susceptibility was predicted. Furthermore, in a debris flow-susceptible site, effective warning and monitoring are essential not only from an economicpoint of view but are also considered as a frontline approach to alleviate hazards. The advantages of the prediction and early monitoring include(1) the acquired results being sent to the central government for policy making;(2) lives and property in mountainous areas can be protected, such as the 570 residents in the Aizi valley, who evacuated successfully before debris flows in 2012;(3) guiding the government to identify the areas of disasters and the preparation for disaster prevention and mitigation, such as predicting disasters in high-risk areas in the period 2012-2017, helping the government to recognize the development trend of disasters;(4) the quantitative prediction of regional debris-flow susceptibility, such as after the Wenchuan earthquake, can promote scientific and sustainable development and socioeconomic planning in earthquake-struck areas. 展开更多
关键词 regional debris flow SUSCEPTIBILITY Prediction model Wenchuan earthquake DROUGHT Southwest China
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Gray domain modeling of regional Karst groundwater flow system——a case study on the Karst system in a hydropower station area
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《Global Geology》 1998年第1期74-74,共1页
关键词 a case study on the Karst system in a hydropower station area flow Gray domain modeling of regional Karst groundwater flow system CASE
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The effects of anisodamine and dobutamine on gut mucosal blood flow during gut ischemia/reperfusion 被引量:23
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作者 Sen Hu Zhi-Yong Sheng,Burns Institute,304th Hospital of PLA,Beijing 100037,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期555-557,共3页
AIM: To determine if anisodamine is able to augment mucosal perfusion during gut I/R ischemia-reperfusion. METHODS: A jejunal sac was formed in Sprague Dawley rat. A Laser Doppler probe and a tonometer were inserted i... AIM: To determine if anisodamine is able to augment mucosal perfusion during gut I/R ischemia-reperfusion. METHODS: A jejunal sac was formed in Sprague Dawley rat. A Laser Doppler probe and a tonometer were inserted into the sac which was filled with saline. The superior mesenteric artery was occluded (SMAO)for 60 minutes followed by 90 minutes of reperfusion. At the end of 60 minutes of SMAO, either 0.2 mg/kg of anisodmine or dobutamine was injected into the jejunal sac. Laser Doppler mucosal blood flow and regional PCO2 (PrCO2)measurements were made. RESULTS: Mucosal blood flow was significantly increased at 30,60 and 90 minutes of reperfusion (R30, R60, R90) when intraluminal anisodamine or dobutamine was present compared to intraluminal saline only(44+/-3.3% or 48+/-4.1% vs 37+/-2.6% at R30, 57+/-5.0% or 56+/-4.7% vs 45+/-2.7% at R60, 64+/-3.3% or 56+/-4.2% vs 48+/-3.4% at R90,respectively P【0.05). Blood flow changes were also reflected by lowering of jejunal PrCO2 measurements after intraluminal anisodamine or dobutamine compared with that of the saline controls (41+/-3.1 mmHg or 44+/-3.0 mmHg vs 49+/-3.7 mmHg at R30,38+/-3.7 mmHg or 40+/-2.1 mmHg vs 47+/-3.8 mmHg at R60,34+/-2.1 mmHg or 39+/-3.0 mmHg vs 46+/-3.4 mmHg at R90, respectively, P【0.05). Most interesting finding was that there were significantly higher mucosal blood flow and lower jejunal PrCO2 in anisodamine group than those in dobutamine group at 90 minutes of reperfusion(64+/-3.3% vs 56+/-4.2% for blood flow or 34+/-2.1 mmHg vs 39+/-3.0 mmHg for PrCO2, respectively, P【0.05), suggesting that anisodamine had a more lasting effect on mucosal perfusion than dobutamine. CONCLUSION: Intraluminal anisodamine and dobutamine can augment mucosal blood flow during gut I/R and alleviate mucosal acidosis. The results provided beneficial effects on the treatment of splanchnic hypoperfusion following traumatic or burn shock. 展开更多
关键词 Animals Carbon Dioxide DOBUTAMINE Intestinal Mucosa Ischemia JEJUNUM Male RATS Rats Sprague-Dawley regional Blood flow Reperfusion Injury Research Support Non-U.S. Gov't Solanaceous Alkaloids
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Flow structure around high-speed train in open air 被引量:8
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作者 田红旗 黄莎 杨明智 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期747-752,共6页
According to the analysis of the turbulent intensity level around the high-speed train, the maximum turbulent intensity ranges from 0.2 to 0.5 which belongs to high turbulent flow. The flow field distribution law was ... According to the analysis of the turbulent intensity level around the high-speed train, the maximum turbulent intensity ranges from 0.2 to 0.5 which belongs to high turbulent flow. The flow field distribution law was studied and eight types of flow regions were proposed. They are high pressure with air stagnant region, pressure decreasing with air accelerating region, low pressure with high air flow velocity region I, turbulent region, steady flow region, low pressure with high air flow velocity region II,pressure increasing with air decelerating region and wake region. The analysis of the vortex structure around the train shows that the vortex is mainly induced by structures with complex mutation and large curvature change. The head and rear of train, the underbody structure, the carriage connection section and the wake region are the main vortex generating sources while the train body with even cross-section has rare vortexes. The wake structure development law studied lays foundation for the train drag reduction. 展开更多
关键词 flow around high-speed train turbulence intensity flow region vortex structure wake region
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Analysis of Bingham fluid radial flow in smooth fractures 被引量:5
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作者 Liangchao Zou Ulf Håkansson Vladimir Cvetkovic 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第5期1112-1118,共7页
Solutions for radial flow of a Bingham fluid are analyzed in this paper.It aims to eliminate confusions in the literature concerning the plug flow region in different solutions for analysis and design of grouting in r... Solutions for radial flow of a Bingham fluid are analyzed in this paper.It aims to eliminate confusions in the literature concerning the plug flow region in different solutions for analysis and design of grouting in rock fractures.The analyses based on the force balance equation reveal that the plug flow region in Bingham radial flow is independent of the fracture radius,and is not a growth function adapted from the solution of one-dimensional(1D)slit flow according to‘similarity’.Based on the shear stress distribution,we analytically proposed that a non-uniform plug flow region cannot exist.The Bingham fluid(grout)penetration and flowrate evolution as functions of grouting time are given using the correct expression for the plug flow region.The radius-independent plug flow region and the presented flowrate evolution equation are also verified numerically.For radial flow,the relative penetration length is equal to the relative width of plug flow region,which is the same as that for 1D channel flow.Discrepancies in analytical solutions for grout penetration and flowrate evolution were also illustrated.The clarification of the plug flow region and evaluation of discrepancies in analytical solutions presented in this work could simplify modeling and design of grouting in rock engineering applications. 展开更多
关键词 Rock grouting Radial flow of Bingham fluids Plug flow region Force balance Energy dissipation Analytical solution
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GPU-based discrete element simulation on flow stability of flat-bottomed hopper 被引量:1
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作者 Li Peng Zheng Zou +2 位作者 Libo Zhang Qingshan Zhu Hongzhong Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期43-52,共10页
In this study, the flow stability of the flat-bottomed hopper was investigated via GPU-based discrete element method(DEM) simulation. With the material height inside the hopper reducing, the fluctuation of the flow ra... In this study, the flow stability of the flat-bottomed hopper was investigated via GPU-based discrete element method(DEM) simulation. With the material height inside the hopper reducing, the fluctuation of the flow rate indicates an unstable discharge. The flow regions of the unstable discharge were compared with that of the stable discharge, a key transformation zone, where the voidage showed the largest difference between unstable and stable discharge, was revealed. To identify the relevance of the key transformation zone and the hopper flow stability, the voidage variation of the key transformation zone with material height reducing was studied.A sharp increase in the voidage in the key transformation zone was considered to be the standard for judging the unstable hopper flow, and the ‘Top–Bottom effect' of the hopper was defined, which indicated the hopper flow was unstable when the hopper only had the top area and the bottom area, because the voidage of particles in the top area and the bottom area were both variables. 展开更多
关键词 Stability Discrete element method(DEM) Granular flow Top-Bottom effect flow regions
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Sap Flow of Abies georgei var. smithii and Its Relationship with the Environment Factors in the Tibetan Subalpine Region, China 被引量:12
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作者 GUO Qi-qiang ZHANG Wen-hui 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1373-1382,共10页
Abies georgei var. smithii is a dominant species playing an important role in protecting biodiversity and sustaining the forestry ecosystems in Southeastern Tibetan Plateau. Stem sap flows of five different diameters ... Abies georgei var. smithii is a dominant species playing an important role in protecting biodiversity and sustaining the forestry ecosystems in Southeastern Tibetan Plateau. Stem sap flows of five different diameters at the breast height(DBH) A. georgei var. smithii samples were monitored continuously with the thermal dissipation probe for the entire growing period in order to understand the water transportation mechanism and the effects of environmental factors on its transpiration and growth. Relative environment factors, temperature and humidity of air, photosynthetically active radiation, rainfall, and wind speed, soil moisture, etc. were measured by the automatic weather stations. Diurnal and seasonal variations in sap flow rate with the different stem diameters and their correlations with meteorological factors were analyzed. The diurnal change in sap flow velocity showed a single-peak curve at the daily time scale, whereas a lower sap flow velocity can be observed in the largest DBH sample tree at night. The maximum average velocity was observed in August, whereas the minimum velocity was observed in January, and a large amount of water evaporated in summer owing to the higher sap flow velocity. In addition, sap flow velocity was closely related to changes in the micrometeorological factors, with average sap flow velocity showing significant linear correlations with air temperature, photosynthetically active radiation, rainfall, and vapor pressure deficit of air and soil moisture. Therefore, some measures, improving the light and temperature conditions, should be taken for protecting A. georgei var. smithii population in the Tibetan Plateau. 展开更多
关键词 Tibet Subalpine region Thermal dissipation probe Abies georgei var.smithii Sap flow velocity Environment factor
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EFFECT OF ELECTROACUPUNCTURE ON CEREBRAL BLOOD FLOW, VIP AND ET IN RATS WITH VASCULAR DEMENTIA
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作者 申国明 徐颖 +1 位作者 何峰 许冠荪 《World Journal of Acupuncture-Moxibustion》 2004年第2期21-24,共4页
Objective: To investigate the relationship between electroacupuncture (EA)-induced improvement of regional cerebral blood flow and the alternations of vasoactive intestinal peptide (VIP) and endothelin (ET) in rats wi... Objective: To investigate the relationship between electroacupuncture (EA)-induced improvement of regional cerebral blood flow and the alternations of vasoactive intestinal peptide (VIP) and endothelin (ET) in rats with experimental vascular dementia (VD). Methods: 40 Wistar rats were evenly randomized into sham-operation, model, medication (Nimotone) and EA groups. Vascular dementia model was established by repeated cerebral ischemia-reperfusion which was induced by occlusion and reopen of the bilateral common carotid arteries. EA (2~200 Hz, 2~3 mA) was applied to "Baihui"(GV 20), "Dazhui"(GV 14) and "Zusanli"(ST 36) for 30 min, once daily and continuously for 15 days. The regional cerebral blood flow (rCBF) in parietal lobe and hippocampus was determined with method of hydrogen clearance; a step-down avoidance test was adopted to observe the rats’ behavior change; and plasma VIP and ET contents were assayed by radioimmunoassay. Results: In comparison with sham-operation group, the correct rate of step-down avoidance test, rCBF in parietal lobe and hippocampus and plasma VIP level in VD model group lowered significantly (P<0.01) and plasma ET increased considerably (P<0.01). However, compared with model group, the correct rate of step-down avoidance test, rCBF values and plasma VIP in EA group raised obviously while plasma ET declined significantly. No significant differences were found between EA and medication groups in the 4 indexes. Conclusion: EA can raise rCBF in the parietal lobe and hippocampus, elevate plasma VIP level and reduce plasma ET in rats with VD. 展开更多
关键词 Vascular dementia regional cerebral blood flow Vasoactive intestinal peptide Endothelin Electroacupuncture
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The Economic Growth with the Flows of Capital & Technology
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作者 Xiaohong Liu 《Chinese Business Review》 2004年第8期70-73,共4页
The difference of regional economy comes from capital dissymmetry, technology dissymmetry, manpower dissymmetry and the information dissymmetry. In the knowledge-based economic ages, globalization and information exce... The difference of regional economy comes from capital dissymmetry, technology dissymmetry, manpower dissymmetry and the information dissymmetry. In the knowledge-based economic ages, globalization and information exceed any age of the history. It provides the new terrace for the balanced development of global economy. The flows of capital and technology improve the regional dissymmetry of production factor. By establishing circulating channels, the flows of the production factor will be enlarged. This will raise the distribution efficiency of global resources and lead to the global economic growth. 展开更多
关键词 regional dissymmetry the flows of capital and technology circulating channelseconomic growth
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STUDY OF REGIONAL STABILITY OF ECD DISTRIBUTION IN NORMAL BRAIN
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作者 李培勇 陈刚 朱承谟 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2001年第1期66-70,共5页
Objective To evaluate in vivo stability of ethylenedylbis cysteine diethylester (ECD) brain SPECT. Methods Each of 13 normal volunteers (31. 2 ± 11. 8 years) has 12 dynamic SPECK scans ac-quired in 60min 1h after... Objective To evaluate in vivo stability of ethylenedylbis cysteine diethylester (ECD) brain SPECT. Methods Each of 13 normal volunteers (31. 2 ± 11. 8 years) has 12 dynamic SPECK scans ac-quired in 60min 1h after an injection of 99mTc-ECD using a triple headed gamma camera equipped with ultra high resolution fan beam collimators. Average counts per pixel were measured from frontal, temporal, parie-tal, occipital regions, cerebellum, basal ganglia, thalamus and white matter. Regional ECD clearance rates, regional gray-to-white matter (G/W) ratios and the change of the G/W ratio were calculated. Results The average ECD clearance rate was 4. 2% /h, ranged from 3. 03% /h to 5. 41% /h corresponding to white matter and occipital. There was no significant difference between regional ECD clearance rates. Regional G 7W ratio was between 1.27 to 1.75. The G/W ratio of temporal lobe was lower than the occipital ( P <0.05). The change of regional G/W ratio with time is slow. Conclusion Regional ECD distribution is stable in normal brain. ECD clearance from brain is slow and no significant regional difference. 展开更多
关键词 regional cerebral blood flow single-photon-emission-tomography normal subject
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Table 1.FDI flows,by region and selected countries,1994-2005
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《China Textile》 2006年第4期7-7,共1页
关键词 FDI Table 1.FDI flows by region and selected countries 1994-2005
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Observation on the effect of acupoint stimulation on regional cerebral blood flow using near-infrared spectroscopy technology 被引量:2
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作者 王桂凤 高木健 +5 位作者 水野海腾 角南芳则 郭义 棚桥伸行 西村甲 石田寅夫 《World Journal of Acupuncture-Moxibustion》 2014年第4期41-48,共8页
Objective To observe the effect of acupuncture at Kongzui(孔最LU 6),Sanyinjiao(三阴交 SP 6) and Zusanli(足三里 ST 36) on cerebral blood oxygenation level and explore the relevance between acupuncture and cerebra... Objective To observe the effect of acupuncture at Kongzui(孔最LU 6),Sanyinjiao(三阴交 SP 6) and Zusanli(足三里 ST 36) on cerebral blood oxygenation level and explore the relevance between acupuncture and cerebral blood oxygenation level using near-infrared spectroscopy(NIRS).Methods Quasi-randomized design(random test sequence) was used.In clinical trial ①,placebo acupuncture was applied at Baihui(百会GV 20) of18 adults.In clinical trial ②,54 adults were divided into three groups with 18 each in which acupuncture was applied at LU 6,SP 6 and ST 36 respectively.Before and after acupuncture,verbal fluency test(VFT) was performed and the blood oxygenation level of cerebral cortex was measured using NIRS.Quantized data was processed with JMP10.0.2 software and SPSS software.Results In clinical trial ①,the mean integral values of cerebral blood oxygenation level were 10.8 mMcm·s and 9.2 mMcm·s respectively before and after acupuncture at GV 20 in placebo acupuncture group.There was no significant difference in the cerebral blood oxygenation level after acupuncture.In clinical trial ②,the mean integral values of cerebral blood oxygen level were18.1 mMcm·s and 8.6 mMcm·s respectively before and after acupuncture at LU 6 in[LU 6]acupuncture group,the cerebral blood oxygenation level was significantly decreased after acupuncture(P = 0.001).The mean integral values of cerebral blood oxygenation level were 16.1 mMcm·s and 17.4 mMcm·s respectively before and after acupuncture at SP 6 in[SP 6]acupuncture group,the cerebral blood oxygenation level was slightly increased after acupuncture,but the increase was not statistically significant.The mean integral values of cerebral blood oxygenation level were 13.8 mMcnvs and 10.1 mMcnvs respectively before and after acupuncture at ST 36 in[ST 36]acupuncture group,the cerebral blood oxygenation level was slightly deceased after acupuncture,but the increase was not statistically significant.Conclusion The cerebral blood oxygenation level of frontal head was decreased by acupuncture at LU 6,the cerebral blood oxygenation level of frontal head was intended to decrease by acupuncture at ST 36.The cerebral blood oxygenation level of frontal head is intended to increase by acupuncture at SP 6. 展开更多
关键词 ACUPUNCTURE Near-infrared Spectroscopy(NIRS) regional cerebral blood flow(rCBF) OXYGENATION
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Effects of San Qi on Gastric Secretion and Protective Factors of Gastric Mucosa in the Rat with Precancerous Lesion of Stomach 被引量:5
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作者 石雪迎 赵凤志 +4 位作者 戴欣 董秀云 方杰 杨会敏 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2003年第3期220-224,共5页
In the model rat with precancerous lesion of stomach induced by the combined method of insertion of a spring into the pylorus and high salt hot paste,effects of San Qi (三七 Radix Notoginseng) on gastric secretion and... In the model rat with precancerous lesion of stomach induced by the combined method of insertion of a spring into the pylorus and high salt hot paste,effects of San Qi (三七 Radix Notoginseng) on gastric secretion and protective factors of stomach were investigated.The results indicated that gastric secretion,gastric mucosal blood flow (GMBF) and aminohexose content lowered significantly,and malondialdehyde (MDA) increased significantly (P<0.01) in the model group as compared with the normal group;after treatment with San Qi Powder for 12 weeks,both gastric secresion and GMBF increased,and MDA content decreased as compared with the negative control group (P<0.01),with no significant increase of aminohexose content.It is suggested that San Qi (三七 Radix Notoginseng) may improve gastric secretion,and that increase of GMBF and antagonism against the lesion of oxygen free radicals are possibly one of its mechanisms. 展开更多
关键词 PANAX Animals Drugs Chinese Herbal Gastric Mucosa Male MALONDIALDEHYDE Precancerous Conditions RATS Rats Wistar regional Blood flow Stomach Neoplasms
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Effect of endothelin and endothelin A receptors on regional cerebral blood flow after traumatic brain injury in rabbits 被引量:7
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作者 张云东 邹咏文 +2 位作者 许民辉 朱佩芳 王正国 《Chinese Journal of Traumatology》 CAS 2000年第3期185-188,共4页
Objective: To investigate the effect of endothelin and endothelin A receptors (ETAR) on regional cerebral blood flow after traumatic brain injury (TBI). Methods: The changes of endothelin 1 (ET 1) content with radioim... Objective: To investigate the effect of endothelin and endothelin A receptors (ETAR) on regional cerebral blood flow after traumatic brain injury (TBI). Methods: The changes of endothelin 1 (ET 1) content with radioimmunoassay, mRNA expression and the location of ETAR with in situ hybridization, and the function and effect of antagonist BQ123 on regional cerebral blood flow (rCBF) through intracisternal application were dynamically observed on 130 adult rabbits after TBI. Results: ET 1 increased significantly in regional brain tissues, and the expression of ETAR mRNA increased apparently and predominantly distributed in the cerebromicrovascular endothelium after trauma. The rCBF declined significantly, but by using selective ETAR antagonist BQ123 to treat the rabbits, the decrease of rCBF could be apparently prevented. Conclusions: It demonstrates that ET 1 may primarily contribute to the rCBF decrease after TBI, while providing that the role of ET 1 is mediated through ETAR. 展开更多
关键词 ENDOTHELINS Receptors endothelin regional blood flow Brain injuries
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Regional cerebral blood flow in children with autism spectrum disorders: a quantitative 99mTc-ECD brain SPECT study with statistical parametric mapping evaluation 被引量:8
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作者 YANG Wen-han JING Jin +4 位作者 XIU Li-juan CHENG Mu-hua WANG Xin BAO Peng WANG Qing-xiong 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第9期1362-1366,共5页
Background Autism spectrum disorders (ASD), which include autism, asperger syndrome (AS) and pervasive developmental disorder-not otherwise specified (PDD-NOS), are devastating neurodevelopmental disorders of ch... Background Autism spectrum disorders (ASD), which include autism, asperger syndrome (AS) and pervasive developmental disorder-not otherwise specified (PDD-NOS), are devastating neurodevelopmental disorders of childhood resulting in deficits in social interaction, repetitive patterns of behaviors, and restricted interests and activities. Single photon emission computed tomography (SPECT) is a common technique used to measure regional cerebral blood flow (rCBF). Several studies have measured rCBF in children with ASD using SPECT, however, findings are discordant. In addition, the majority of subjects used in these studies were autistic. In this study, we aimed to investigate changes in rCBF in children with ASD using SPECT.Methods A Technetium-99m-ethyl cysteinate dimmer (99mTc-ECD) brain SPECT study was performed on an ASD group consisting of 23 children (3 girls and 20 boys; mean age (7.2±3.0) years) who were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-Ⅳ) criteria and an age-matched control group with 8children (1 girl and 7 boys, mean age (5.5±2.4) years). Image data were evaluated with Statistical Parametric Mapping,5th version (SPM5). A Student's t test for unpaired data was used to compare rCBF and asymmetry in the autism and corresponding control group. The covariance analysis, taking age as covariance, was performed between the ASD and control group.Results There was a significant reduction in rCBF in the bilateral frontal lobe (frontal poles, arcula frontal gyrus) and the bilateral basal ganglia in the autism group, and a reduction in the bilateral frontal, temporal, parietal, legumina nucleus and cerebellum in the AS group compared to the control. In addition, asymmetry of hemispheric hypoperfusion in the ASD group was observed. Inner-group comparison analysis revealed that rCBF decreased significantly in the bilateral frontal lobe (42.7%), basal nucleus (24.9%) and temporal lobe (22.8%) in the autism group, and in the bilateral cerebellum (22.8%), basal nucleus (19.3%) and right thalamencephalon (16.6%)in the AS group (P <0.05).Conclusions The decrease in rCBF in ASD is a global event, which involves the bilateral frontal, temporal, limbic system and basal ganglias. Asymmetry of hemispheric hypoperfusion was more obvious in the AS group than the autism group, which indicates a different neurobiological mechanism from that of autism. 展开更多
关键词 autism spectrum disorders single photon emission computed tomography regional cerebral blood flow
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Laser Doppler flowmeter study on regional cerebral blood flow in early stage after standard superficial temporal artery-middle cerebral artery bypass surgery for moyamoya disease 被引量:5
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作者 GESANG Dun-zhu ZHANG Dong ZHAO Ji-zong WANG Shuo ZHAO Yuan-li WANG Rong SUN Jian-jun MENG Ze 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第20期2412-2418,共7页
Background Standard superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery is an effective treatment for moyamoya disease, but recent evidence suggests that postoperative cerebral hyperperfusion... Background Standard superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery is an effective treatment for moyamoya disease, but recent evidence suggests that postoperative cerebral hyperperfusion can occur. In this study, the trendline of changes in regional cerebral blood flow (rCBF) after surgery were continually monitored near the site of anastomosis in order to investigate both the efficacy of the procedure for improving rCBF and the possible risk of hyperperfusion . Methods Standard STA-MCA bypass surgery was performed on 13 patients, rCBF was measured continually using laser Doppler flowmetry (LDF) until the 5th day after the operation with the LDF probe implanted adjacent to the area of the anastomosis. The trendline of rCBF changes postoperatively was recorded for the analysis performed using SPSS 13.0. Results The baseline LDF value of cortical rCBF was (84.68±14.39) perfusion unit (PU), which was linear relative to absolute perfusion volume before anastomosis and (88.90±11.26) PU immediately after anastomosis (P 〉0.05). The value changed significantly from before to after anastomosis (P 〈0.05); it was (417.72±21.35) PU on the 1st day after surgery, and (358.99±18.01) PU, (323.46±17.38) PU, (261.60±16.38) PU and (375.72±18.45) PU on the following 4 days, respectively. The rCBF decreased gradually from the 2nd day until the 4th postoperative day, but still was at a high level (P 〈0.05). However, on the 5th postoperative day the rCBF increased again to the second highest level, which was significantly different compared with the baseline value (P 〈0.05), but not significantly different compared with the values on the other 4 days (P〉0.05). Conclusions STA-MCA anastomosis improves the cerebral blood supply significantly in the early stage after surgery, however, the risk of symptomatic hyperperfusion may exist, which may possibly occur on the 1st day and 5th day after surgery. A LDF is useful for postoperative monitoring for both the efficacy of bypass and possible risk of neurologic deterioration or bleeding from hyperperfusion. 展开更多
关键词 moyamoya disease STA-MCA bypass laser-Doppler flowmetry regional cerebral blood flow
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Apolipoprotein E polymorphisms increase the risk of post-stroke depression 被引量:13
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作者 Xue-bin Li Jie Wang +4 位作者 An-ding Xu Jian-min Huang Lan-qing Meng Rui-ya Huang Jun-li Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第11期1790-1796,共7页
Recent reports have shown that apolipoprotein E (APOE) polymorphisms are involved in neurodegenerative disease. However, it is unclear whether APOE affects post-stroke depression. Accordingly, we hypothesized that A... Recent reports have shown that apolipoprotein E (APOE) polymorphisms are involved in neurodegenerative disease. However, it is unclear whether APOE affects post-stroke depression. Accordingly, we hypothesized that APOE polymorphisms modify the risk of post-stroke depression. Here, we performed a hospital-based case-control study (including 76 cerebral infarction cases with post-stroke depression, 88 cerebral infarction cases without post-stroke depression, and 109 controls without any evidence of post-stroke depression or cerebral infarction) to determine possible association between APOE rs429358 and rs7412 polymorphisms and risk of post-stroke depression. Our findings show no difference among the groups with regards genotype distribution of the rs7412 polymorphism. In contrast, APOE genotypes with rs429358-C alleles increased the risk of post-stroke depression. Further, the rs429358 polymorphism was associated with significantly decreased regional cerebral blood flow values in the left temporal lobe of post-stroke depression cases. Additionally, the rs429358 polymorphism was not only associated with depression severity, but with increasing serum levels of total cholesterol. These resuits suggest that the APOE rs429358 polymorphism is associated with increased risk of developing post-stroke depression, and that APOE rs429358-C allele genotypes may be detrimental to recovery of nerve function after stoke. Indeed, these findings provide clinical data for future post-stroke depression gene interventions. 展开更多
关键词 nerve regeneration apolipoprotein E genetic polymorphism post-stroke depression RISK regional resting-state cerebral blood flow rs429358 rs7412 cerebral infarction neural regeneration
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