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Relationship of Microvascular Obstruction with Global and Regional Myocardial Function Determined by Cardiac Magnetic Resonance after ST-Segment Elevation Myocardial Infarction
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作者 Ya-Nan Zhao Jia-Ning Cui +4 位作者 Xing-Hua Zhang Jin-Feng Li Shi-Min Chen Xiu-Zheng Yue Tao Li 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第1期11-19,共9页
Objective To investigate the impact of microvascular obstruction(MVO)on the global and regional myocardial function by cardiac magnetic resonance feature-tracking(CMR-FT)in ST-segment-elevation myocardial infarction(S... Objective To investigate the impact of microvascular obstruction(MVO)on the global and regional myocardial function by cardiac magnetic resonance feature-tracking(CMR-FT)in ST-segment-elevation myocardial infarction(STEMI)patients after percutaneous coronary intervention.Methods Consecutive acute STEMI patients who underwent cardiac magnetic resonance imaging 1-7 days after successful reperfusion by percutaneous coronary intervention treatment were included in this retrospective study.Based on the presence or absence of MVO on late gadolinium enhancement images,patients were divided into groups with MVO and without MVO.The infarct zone,adjacent zone,and remote zone were determined based on a myocardial 16-segment model.The radial strain(RS),circumferential strain(CS),and longitudinal strain(LS)of the global left ventricle(LV)and the infarct,adjacent,and remote zones were measured by CMRFT from cine images and compared between patients with and without MVO using independent-samples t-test.Logistic regression analysis was used to assess the association of MVO with the impaired LV function.Results A total of 157 STEMI patients(mean age 56.66±11.38 years)were enrolled.MVO was detected in 37.58%(59/157)of STEMI patients,and the mean size of MVO was 3.00±3.76 mL.Compared with patients without MVO(n=98),the MVO group had significantly reduced LV global RS(t=-4.30,P<0.001),global CS(t=4.99,P<0.001),and global LS(t=3.51,P=0.001).The RS and CS of the infarct zone in patients with MVO were significantly reduced(t=-3.38,P=0.001;t=2.64,P=0.01;respectively)and the infarct size was significantly larger(t=8.37,P<0.001)than that of patients without MVO.The presence of LV MVO[OR=4.10,95%CI:2.05-8.19,P<0.001]and its size[OR=1.38,95%CI:1.10-1.72,P=0.01],along with the heart rate and LV infarct size were significantly associated with impaired LV global CS in univariable Logistic regression analysis,while only heart rate(OR=1.08,95%CI:1.03-1.13,P=0.001)and LV infarct size(OR=1.10,95%CI:1.03-1.16,P=0.003)were independent influencing factors for the impaired LV global CS in multivariable Logistic regression analysis.Conclusion The infarct size was larger in STEMI patients with MVO,and MVO deteriorates the global and regional LV myocardial function. 展开更多
关键词 cardiac magnetic resonance feature tracking ST-segment elevation myocardial infarction microvascular obstruction myocardial strain myocardial function
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Assessment of Regional Myocardial Function in Patients with Hypertrophic Cardiomyopathy by Tissue Strain Imaging 被引量:2
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作者 熊润青 谢明星 +1 位作者 王新房 吕清 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第3期334-337,共4页
The value of tissue strain imaging (SI) in regional myocardial systolic and diastolic function assessment was studied. In 18 patients with nonobstructive hypertrophic cardiomyopathy (HCM) and 20 age-matched healthy su... The value of tissue strain imaging (SI) in regional myocardial systolic and diastolic function assessment was studied. In 18 patients with nonobstructive hypertrophic cardiomyopathy (HCM) and 20 age-matched healthy subjects, regional myocardial longitudinal peak systolic strain in eject time (represented by εet) was measured at basal, mid and apical segments of septal, lateral and posterior walls of the left ventricle (LV) and compared between groups. εet had no significant difference between segments in control group (P>0.05), which displayed a decreasing trend from basal segments to apical ones. εet in the HCM group was significantly decreased (P<0.05) as compared with that in the healthy group. In the HCM group, εet in the midseptum was significantly less than at the basal and apical septum, and was also less than at the rest LV walls in the same group (P<0.01). The systolic reversed εet was noticed in 35 % of the hypertrophic segments in HCM group. Significantly negative correlation existed between the absolute value of εet and wall thickness in the midseptum (r=-0.83). The post-systolic strain(PSS) segment number the and amplitudes in healthy group were significantly less than those in HCM group (P<0.05). Both regional myocardial systolic and diastolic functions were impaired in hypertrophic or non-hypertrophic segments in patients with the HCM, especially in hypertrophic segments. Strain imaging technique is a sensitive and accura tool in myocardial dysfunction assessment. 展开更多
关键词 心肌功能 肥大性心肌病 组织应变 超声检查
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Trade-off and Synergy of Rural Functions Under County Depopulation in the Typical Black Soil Region of Northeast China
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作者 LI Dongmei WEN Qing +1 位作者 QI Yue ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2023年第4期616-633,共18页
As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainab... As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainable development.In this study,we focused on the impacts of depopulation on the evolution and interrelationship of rural subfunctions.Based on the rural function indexes system,the TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)method,spatial analysis method,and mathematical statistics analysis method were used to summarize the spatial and temporal characteristics of rural function development,as well as the effect of population shrinkage in the typical black soil region of Northeast China.The results showed that depopulation varied in the extent and duration between the forested region and plain areas,which both impacted the trajectories of rural subfunctions evolution.For the economic development function and ecological conservation function,the effect of continuous slight depopulation was beneficial,while the effect of rapid depopulation was adverse,which was exactly opposite to the agricultural production function.All forms of population shrinkage were conducive to the development of the social security function.With the deepening population shrinkage,depopulation mainly promoted the collaborative development between subfunctions in this study,except the relationship between agricultural production and social security function.But effects of depopulation on the interrelationship of rural subfunctions varied between the forested region and plain areas in some cases.The results provided evidence for the cognition that population shrinkage had complicated effects on rural subfunctions. 展开更多
关键词 rural function depopulation trade-off and synergy typical black soil region Northeast China
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Spatial Agglomeration and Diffusion of Population Based on a Regional Density Function Approach:A Case Study of Shandong Province in China
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作者 Xiaohan Zhao Yanbin Chen 《Journal of Geographical Research》 2023年第3期61-80,共20页
Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,C... Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,China,but few have applied regional density functions to the analysis.Therefore,based on the 2000,2010,and 2020 population censuses,this study used monocentric and polycentric regional density functions to study the characteristics of population agglomeration and diffusion in Shandong.This is followed by an in-depth discussion based on population growth rate data and hot-and cold-spot analyses.The results showed that the Shandong Province population was spatially unevenly distributed.Population growth rates were higher in urban centers and counties,with more significant changes in population size in the eastern coastal areas than in the inland areas.As verified in this study,the logarithmic form of the single-center regional density function R2 was greater than 0.8,which was in line with the population spatial structure of Shandong Province.During the study period,the estimated population density of the regional center and the absolute value of the regional population density gradient both increased,indicating a clear and increasing trend of centripetal agglomeration of regional centers over the study period.Overall,the R2 value of the multicenter region density function was higher than that of the single-center region density function.The polycentric regional density function showed that the population density gradient of some centers had a downward trend,which reflected the spatial development trend of outward diffusion in these centers.Meanwhile,the variation in the estimated population density and the population density gradient exhibited differences in the central population distribution patterns at different levels. 展开更多
关键词 regional density functions Population spatial structure Shandong Province
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Specific alterations of regional myocardial work in strength-trained athletes using anabolic androgenic steroids compared to athletes with genetic hypertrophic cardiomyopathy
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作者 Antoine Grandperrin Frédéric Schnell +4 位作者 Erwan Donal Elena Galli Christophe Hedon Olivier Cazorla Stéphane Nottin 《Journal of Sport and Health Science》 SCIE CAS CSCD 2023年第4期477-485,共9页
Background:Strength-trained athletes using anabolic androgenic steroids(AAS)have left ventricular(LV)hypertrophy and myocardial fibrosis that can lead to sudden cardiac death.A similar feature was described in athlete... Background:Strength-trained athletes using anabolic androgenic steroids(AAS)have left ventricular(LV)hypertrophy and myocardial fibrosis that can lead to sudden cardiac death.A similar feature was described in athletes with hypertrophic cardiomyopathy(HCM),which complicates the diagnosis for clinicians.In this context,we aimed to compare the LV function of the 2 populations by measuring global and regional strain and myocardial work using speckle-tracking imaging.Methods:Twenty-four strength-trained asymptomatic athletes using AAS(AAS-Athletes),22 athletes diagnosed with HCM(HCM-Athletes),and 20 healthy control athletes(Ctrl-Athletes)underwent a resting echocardiography to assess LV function.We evaluated LV global and regional strains and myocardial work,with an evaluation of the constructive work(CW),wasted work,and work efficiency(WE).Results:Compared to Ctrl-Athletes,both AAS-Athletes and HCM-Athletes had a thicker interventricular septum,with maj ored values in HCM-Athletes.LV strain was reduced in AAS-Athletes and even more in HCM-Athletes.Consequently,global WE was significantly diminished in both AAS and HCM-Athletes(93%±2%in Ctrl-Athletes,90%±4%in AAS-Athletes,and 90%±5%in HCM-Athletes(mean±SD);p<0.05).Constructive work and WE regional analysis showed specific alterations,with the basal septal segments preferentially affected in AAS-Athletes,and both septal and apical segments affected in HCM-Athletes.Conclusion:The regional evaluation of myocardial work reported specific alterations of the major LV hypertrophy induced by the regular use of AAS compared to the LV hypertrophy due to HCM.This finding could help clinicians to differentiate between these 2 forms of pathological hypertrophy. 展开更多
关键词 Anabolic androgenic steroids Hypertrophic cardiomyopathy Left ventricular function myocardial work Speckle-tracking echocardiography
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Determination of the degree 120 time-variable gravity field in the Sichuan-Yunnan region using Slepian functions and terrestrial measurements 被引量:4
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作者 Jiancheng Han Shi Chen +2 位作者 Zhaohui Chen Hongyan Lu Weimin Xu 《Earthquake Science》 2021年第3期211-221,共11页
The terrestrial time-variable gravity measurements are characterized by a high signal-to-noise ratio and sensitivity to the sources of mass change in the Earth's crust.These gravity data have many applications,suc... The terrestrial time-variable gravity measurements are characterized by a high signal-to-noise ratio and sensitivity to the sources of mass change in the Earth's crust.These gravity data have many applications,such as surface deformation,groundwater storage changes,and mass migration before and after earthquakes.Based on repeated terrestrial gravity measurements at 198 gravity stations in the Sichuan-Yunnan region(SYR)from 2015 to 2017,we determine a time series of degree 120 gravity fields using the localized spherical harmonic(Slepian)basis functions.Our results show that adopting the first 6 Slepian basis functions is sufficient for effective localized Slepian modeling in the SYR.The differences between two gravity campaigns at the same time of year show an obvious correlation with tectonic features.The degree 120 timevariable gravity models presented in this paper will benefit the study of the regional mass migration inside the crust of the SYR and supplement the existing geophysical models for the China Seismic Experimental Site. 展开更多
关键词 Sichuan-Yunnan region terrestrial gravity measurements time-variable gravity Slepian basis function regional gravity field
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Spatial Function Regionalization Based on an Ecological-economic Analysis in Wuxi City, China
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作者 SUN Wei CHEN Wen JIN Zhifeng 《Chinese Geographical Science》 SCIE CSCD 2019年第2期352-362,共11页
As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundw... As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundwork for the regulation of land use and protection. This paper probes the system of evaluation indices and applies the methods of spatial analysis and classification clustering to the calculation of the ecologically significant value and economically significant value in each evaluation unit. After use of a classification matrix integrated by the two significant values, city space can be divided into four functional types, namely, feasible development area, moderate development area, moderate conservation area and prohibited exploiting area, and these are the basis for spatial development and control. 展开更多
关键词 SPATIAL function regionALIZATION SPATIAL analysis ecologically SIGNIFICANT VALUE economically SIGNIFICANT VALUE urbanized region
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Ecological function regionalization of fluvial corridor landscapes and measures for ecological regeneration in the middle and lower reaches of the Tarim River, Xinjiang of China 被引量:2
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作者 Zhou, HuaRong Xia, DuNing 《Journal of Arid Land》 SCIE 2010年第2期123-132,共10页
The middle and lower reaches of the Tarim River are currently one of the main regions of ecological restoration in the arid areas of western China.Using the principles and method of landscape ecology,this study has ch... The middle and lower reaches of the Tarim River are currently one of the main regions of ecological restoration in the arid areas of western China.Using the principles and method of landscape ecology,this study has chosen the fluvial corridor landscape in the middle and lower reaches of the Tarim River,and discusses the region's ecologically functional regionalization system and issues related to its practical classification.On this basis the corresponding regionalizing principles and standards were developed which were used to qualitatively divide the three main landscapes as the ecologically functional areas in the drainage basin.The paper has also analyzed the characteristic of the study areas,and has put forward the measures for its ecological restoration. 展开更多
关键词 FLUVIAL CORRIDOR landscape ECOLOGICAL function regionALIZATION ECOLOGICAL REGENERATION TARIM River
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Altered spontaneous brain activity in patients with diabetic optic neuropathy:A resting-state functional magnetic resonance imaging study using regional homogeneity 被引量:1
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作者 Gui-Ying Guo Li-Juan Zhang +7 位作者 Biao Li Rong-Bin Liang Qian-Min Ge Hui-Ye Shu Qiu-Yu Li Yi-Cong Pan Chong-Gang Pei Yi Shao 《World Journal of Diabetes》 SCIE 2021年第3期278-291,共14页
BACKGROUND Diabetes is a common chronic disease.Given the increasing incidence of diabetes,more individuals are affected by diabetic optic neuropathy(DON),which results in decreased vision.Whether DON leads to abnorma... BACKGROUND Diabetes is a common chronic disease.Given the increasing incidence of diabetes,more individuals are affected by diabetic optic neuropathy(DON),which results in decreased vision.Whether DON leads to abnormalities of other visual systems,including the eye,the visual cortex,and other brain regions,remains unknown.AIM To investigate the local characteristics of spontaneous brain activity using regional homogeneity(ReHo)in patients with DON.METHODS We matched 22 patients with DON with 22 healthy controls(HCs).All subjects underwent resting-state functional magnetic resonance imaging.The ReHo technique was used to record spontaneous changes in brain activity.Receiver operating characteristic(ROC)curves were applied to differentiate between ReHo values for patients with DON and HCs.We also assessed the correlation between Hospital Anxiety and Depression Scale scores and ReHo values in DON patients using Pearson correlation analysis.RESULTS ReHo values of the right middle frontal gyrus(RMFG),left anterior cingulate(LAC),and superior frontal gyrus(SFG)/left frontal superior orbital gyrus(LFSO)were significantly lower in DON patients compared to HCs.Among these,the greatest difference was observed in the RMFG.The result of the ROC curves suggest that ReHo values in altered brain regions may help diagnose DON,and the RMFG and LAC ReHo values are more clinically relevant than SFG/LFSO.We also found that anxiety and depression scores of the DON group were extremely negatively correlated with the LAC ReHo values(r=-0.9336,P<0.0001 and r=-0.8453,P<0.0001,respectively).CONCLUSION Three different brain regions show ReHo changes in DON patients,and these changes could serve as diagnostic and/or prognostic biomarkers to further guide the prevention and treatment of DON patients. 展开更多
关键词 DIABETES Diabetic optic neuropathy regional homogeneity Resting state functional magnetic resonance imaging Brain activity
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Exploring the Abnormal Brain Regions and Abnormal Functional Connections in SZ by Multiple Hypothesis Testing Technique
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作者 Lan Yang Shun Qi +1 位作者 Chen Qiao Yanmei Kang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期215-237,共23页
Schizophrenia(SZ)is one of the most common mental diseases.Its main characteristics are abnormal social behavior and inability to correctly understand real things.In recent years,the magnetic resonance imaging(MRI)tec... Schizophrenia(SZ)is one of the most common mental diseases.Its main characteristics are abnormal social behavior and inability to correctly understand real things.In recent years,the magnetic resonance imaging(MRI)technique has been popularly utilized to study SZ.However,it is still a great challenge to reveal the essential information contained in the MRI data.In this paper,we proposed a biomarker selection approach based on the multiple hypothesis testing techniques to explore the difference between SZ and healthy controls by using both functional and structural MRI data,in which biomarkers represent both abnormal brain functional connectivity and abnormal brain regions.By implementing the biomarker selection approach,six abnormal brain regions and twenty-three abnormal functional connectivity in the brains of SZ are explored.It is discovered that compared with healthy controls,the significantly reduced gray matter volumes are mainly distributed in the limbic lobe and the basal ganglia,and the significantly increased gray matter volumes are distributed in the frontal gyrus.Meanwhile,it is revealed that the significantly strengthened connections are those between the middle frontal gyrus and the superior occipital gyrus,the superior occipital gyrus and the middle occipital gyrus as well as the middle occipital gyrus and the fusiform gyrus,and the rest connections are significantly weakened. 展开更多
关键词 Multiple hypothesis testing SCHIZOPHRENIA magnetic resonance imaging abnormal brain regions abnormal functional connectivity
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Effect of Salt Stress on Nitrogen Assimilation of Functional Leaves and Root System of Rice in Cold Region
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作者 Gu Jiao-jiao Zhao Hong-wei +4 位作者 Jia Yan Hu Bo-wen Wang Zhuo-qian Qu Zhao-jun Yu Feng-li 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第2期9-16,共8页
The aims were to investigate the effect of salt stress on key enzyme activity of nitrogen metabolism and the concentration of nitrate nitrogen and ammonium nitrogen response to salt stress.Two rice cultivars,Mudanjian... The aims were to investigate the effect of salt stress on key enzyme activity of nitrogen metabolism and the concentration of nitrate nitrogen and ammonium nitrogen response to salt stress.Two rice cultivars,Mudanjiang 30(sensitive cultivar)and Longdao 5(salt-tolerant cultivar),were treated with different salt concentrations(CK 0%,S10.075%,S20.15%,S30.225%and S40.3%).The results showed that the activities of nitrate reductase(NR),glutamine synthase(GS),glutamate synthase(GOGAT)and glutamate dehydrogenase(GDH)in the functional leaves and roots of rice in cold region presented a single peak curve change and the peak occurred in the heading stage;compared with those of the CK,the activities of NR,GS and GOGAT of rice in cold region decreased,but the activity of GDH increased in the heading stage under salt stress.The variation for key enzyme activity of nitrogen metabolism was the highest under S4 treatment.The activities of NR,GS and GOGAT in the functional leaves significantly decreased compared with those in roots;the concentrations of nitrate nitrogen and ammonium nitrogen in the functional leaves and roots of rice in cold region presented a single peak curve change and the peak occurred in the heading stage;compared with that of the CK,the concentration of nitrate nitrogen decreased in leaves and roots,the concentration of ammonium nitrogen decreased and the concentration of ammonium nitrogen in roots increased under salt stress.The variations for the activities of NR,GS and GOGAT in the functional leaves and roots of Longdao 5 were less than those of Mudanjiang 30 under the same concentration of salt stress. 展开更多
关键词 rice in cold region salt stress functional leave root system nitrogen metabolism
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S-wave velocity structure in Tangshan earthquake region and its adjacent areas from joint inversion of receiver functions and surface wave dispersion
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作者 Yanna Zhao Yonghong Duan +1 位作者 Zhuoxin Yang Zhanyong Gao 《Earthquake Science》 2020年第1期42-52,共11页
Using the seismic records of 83 temporary and 17 permanent broadband seismic stations deployed in Tangshan earthquake region and its adjacent areas(39°N–41.5°N,115.5°E–119.5°E),we conducted a non... Using the seismic records of 83 temporary and 17 permanent broadband seismic stations deployed in Tangshan earthquake region and its adjacent areas(39°N–41.5°N,115.5°E–119.5°E),we conducted a nonlinear joint inversion of receiver functions and surface wave dispersion.We obtained some detailed information about the Tangshan earthquake region and its adjacent areas,including sedimentary thickness,Moho depth,and crustal and upper mantle S-wave velocity.Meanwhile,we also obtained the vP/vS structure along two sections across the Tangshan region.The results show that:(1)the Moho depth ranges from 30 km to 38 km,and it becomes shallower from Yanshan uplift area to North China basin;(2)the thickness of sedimentary layer ranges from 0 km to 3 km,and it thickens from Yanshan uplift region to North China basin;(3)the S-wave velocity structure shows that the velocity distribution of the upper crust has obvious correlation with the surface geological structure,while the velocity characteristics of the middle and lower crust are opposite to that of the upper crust.Compared with the upper crust,the heterogeneity of the middle and lower crust is more obvious;(4)the discontinuity of Moho on the two sides of Tangshan fault suggests that Tangshan fault cut the whole crust,and the low vS and high vP/vS beneath the Tangshan earthquake region may reflect the invasion of mantle thermal material through Tangshan fault. 展开更多
关键词 Tangshan earthquake region joint inversion surface wave dispersion receiver functions S-wave velocity
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Regional Logistics Demand Forecast Based on Least Square and Radial Basis Function
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作者 魏乐琴 张安国 《Journal of Donghua University(English Edition)》 EI CAS 2020年第5期446-454,共9页
Regional logistics demand forecast is the basis for government departments to make logistics planning and logistics related policies.It has the characteristics of a small amount of data and being nonlinear,so the trad... Regional logistics demand forecast is the basis for government departments to make logistics planning and logistics related policies.It has the characteristics of a small amount of data and being nonlinear,so the traditional prediction method can not guarantee the accuracy of prediction.Taking Xiamen City as an example,this paper selects the primary industry,the secondary industry,the tertiary industry,the total amount of investment in fixed assets,total import and export volume,per capita consumption expenditure,and the total retail sales of social consumer goods as the influencing factors,and uses a combining model least square and radial basis function(LS-RBF)neural network to analyze the related data from years 2000 to 2019,so as to predict the logistics demand from years 2020 to 2024.The model can well fit the training data,and the experimental results obtained from the comparison between the predicted value and the actual value in 2019 show that the error rate is very small.Therefore,the prediction results are reasonable and reliable.This method has high prediction accuracy,and it is suitable for irregular regional logistics demand forecast. 展开更多
关键词 regional logistics demand forecast least square and radial basis function(LS-RBF)
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Speckle tracking echocardiography:A new approach to myocardial function 被引量:19
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作者 Simona Sitia Livio Tomasoni Maurizio Turiel 《World Journal of Cardiology》 CAS 2010年第1期1-5,共5页
Echocardiography is the most common diagnostic method for assessing cardiac function but some limitations affect this technique.Until now,visual assessment of wall motion and thickening has allowed only a subjective e... Echocardiography is the most common diagnostic method for assessing cardiac function but some limitations affect this technique.Until now,visual assessment of wall motion and thickening has allowed only a subjective evaluation of myocardial function and requires long-term training.Recently,new echocardiographic techniques have been introduced to evaluate myocardial mechanics.Tissue Doppler imaging(TDI)technique is limited by angle-dependency such that only deformation along the ultrasound beam can be derived from velocities,while myocardium deforms simultaneously in three dimensions.Speckle tracking echocardiography (STE)is a more recent technique that provides a global approach to left ventricular myocardial mechanics,giving information about the three spatial dimensions of cardiac deformation.In this editorial,we describe the physical and pathophysiological concepts of STE,discussing the differences compared to TDI and underlining the pitfalls of this new technique. 展开更多
关键词 myocardial function SPECKLE TRACKING ECHOCARDIOGRAPHY TISSUE DOPPLER imaging
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Speckle tracking echocardiography to assess regional ventricular function in patients with apical hypertrophic cardiomyopathy 被引量:7
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作者 María Cristina Saccheri Tomás Francisco Cianciulli +7 位作者 Luis Alberto Morita Ricardo JoséMéndez Martín Alejandro Beck Juan Enrique Guerra Alberto Cozzarin Luciana Jimena Puente Lorena Romina Balletti Jorge Alberto Lax 《World Journal of Cardiology》 CAS 2017年第4期363-370,共8页
AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patient... AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patients(mean age 53 ± 16 years,range:18-81 years,10 were male),with apical HCM. We measured global longitudinal peak systolic strain(GLPSS) in the midwall and endocardium of the left ventricle. RESULTS The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolicfunction with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular(LV) systolic function,midwall GLPSS was decreased in all patients,more in the apical(-7.3% ±-8.8%) than in basal segments(-15.5% ±-6.93%),while endocardial GLPPS was significantly greater and reached normal values(apical:-22.8% ±-7.8%,basal:-17.9% ±-7.5%). CONCLUSION This study shows that two-dimensional strain was decreased mainly confined to the mesocardium,while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM. 展开更多
关键词 顶端的 hypertrophic 心肌症 二维的紧张 追踪的点缀 心内膜 Midwall 地区性的心肌的收缩功能
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Major Function Oriented Zone: New Method of Spatial Regulation for Reshaping Regional Development Pattern in China 被引量:31
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作者 FAN Jie SUN Wei +1 位作者 ZHOU Kan CHEN Dong 《Chinese Geographical Science》 SCIE CSCD 2012年第2期196-209,共14页
Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article anal... Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented. 展开更多
关键词 区域经济发展 空间结构 中国政府 功能区 文化遗产保护 规例 区域协调发展 GDP增长率
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Functional regionalization with the restriction of ecological shelter zones: A case of Zhaotong in Yunnan 被引量:6
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作者 DU Yu WANG Chuansheng ZHAO Haiying YANG Xiaoguang 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期365-374,共10页
生态的躲蔽处地区重建是瞄准到国家,区域和盆的生态的安全的生态系统恢复和保存工程。长江的上面的活动范围的生态的躲蔽处地区的重建成为了西方的发展策略的最重要的任务之一。这篇文章,作为一个例子拿 Zhaotong,学习生态的躲蔽处... 生态的躲蔽处地区重建是瞄准到国家,区域和盆的生态的安全的生态系统恢复和保存工程。长江的上面的活动范围的生态的躲蔽处地区的重建成为了西方的发展策略的最重要的任务之一。这篇文章,作为一个例子拿 Zhaotong,学习生态的躲蔽处地区的功能的区域化。学习为其主要任务是环境保留的小、中等的区域的功能的区域化供应一个盒子。与功能的区域化的理论的指导,并且基于 Zhaotong 鈥檚 天赋的分析,生态、社会经济的因素,纸为因素建议五个原则选择。这些原则包括:(1 ) 颠倒顺序评估;(2 ) 选择主要因素;(3 ) 保留镇的行政区域的完全;并且(4 ) 由本地管理使产品可接受。为了分析选择因素,在 2002 的 LUCC 数据, 1:50,000 消除地图和镇单位的空间地位,在 2004 的社会经济的统计数据被使用。RS 和 GIS 工具也被使用融化传统、现代的地理方法。这将对在多山的区域的功能的区域化研究有用。作为一个结论,生态的保存或经济开发的领先的功能的区域分别地被建议。Zhaotong 城市被划分成二水平的功能的区域。第一水平包括三条带功能的区域和他们将带分区的发展中的方向。秒级包括八个分区,它是实现的政策区域,和愿望供应指导到 Zhaotong 鈥檚 生态的躲蔽处地区重建。 展开更多
关键词 生态保护区 云南 昭通 功能区划
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Effect of Trimetazidine Dihydrochloride Tablets adjuvant therapy on inflammatory reaction, oxidative stress, vascular endothelial function and myocardial function in patients with coronary heart disease complicated with heart failure 被引量:2
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作者 Cai-Wen Wei Zhi-Hua Li +3 位作者 Lei Song Da-Min Huang Ying-Min Lu Xiao-Han Luo 《Journal of Hainan Medical University》 2017年第21期21-25,共5页
Objective: To investigate the effects of Trimetazidine Dihydrochloride Tablets on inflammatory reaction, oxidative stress, vascular endothelial function and myocardial function in patients with coronary heart disease ... Objective: To investigate the effects of Trimetazidine Dihydrochloride Tablets on inflammatory reaction, oxidative stress, vascular endothelial function and myocardial function in patients with coronary heart disease complicated with heart failure. Methods: A total of 98 patients with coronary heart disease and heart failure who met the criteria of the study were selected as the subjects, based on the random data table they were divided into the control group (n=49) and observation group (n=49), the patients in the control group were treated with Metoprolol Tartrate Sustained-release Tablets treatment, and the patients in the observation group were treated with Metoprolol Tartrate Sustained-release Tablets combined with Trimetazidine Dihydrochloride Tablets, the levels of inflammatory reaction, oxidative stress, vascular endothelial function and myocardial function indexes were compared between the two groups before and after treatment. Results: The difference of the CRP, TNF-α, MDA, SOD, NO, ET-1, LVEF, LVEDD and LVESD levels in the two groups before treatment were not statistically significant;Compared with the levels of the two groups before treatment, the two groups of CRP, TNF-α, MDA, ET-1, LVEDD and LVESD levels after treatment were significantly decreased, and the level of the observation group after treatment was significantly lower than those levels in the control group, the difference was statistically significant;The levels of SOD, NO and LVEF of the two groups after treatment were significantly higher than those in the same group before treatment, and the observation group levels [(88.09±7.51) U/ml, (72.58±14.64) mol/L, (48.34±5.09)% ] were significantly higher than the control group [(79.44±7.27) U/ml, (61.89±11.06) mol/L, (44.19±4.58)%], the difference was statistically significant. Conclusion: Trimetazidine Dihydrochloride Tablets in the treatment of coronary heart disease with heart failure can effectively inhibit the release of inflammatory factors, improve oxidative stress state, vascular endothelial function and myocardial function, has an important clinical value. 展开更多
关键词 Coronary HEART disease with HEART failure TRIMETAZIDINE Dihydrochloride TABLETS Inflammatory factors Oxidative stress Vascular ENDOTHELIAL function myocardial function
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Roles and Functions of Tourism Destinations in Tourism Region of South Anhui:A Tourist Flow Network Perspective 被引量:8
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作者 LIU Fajian ZHANG Jinhe +3 位作者 ZHANG Jie CHEN Dongdong LIU Zehua LU Song 《Chinese Geographical Science》 SCIE CSCD 2012年第6期755-764,共10页
Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the persp... Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the perspective of relationship.This article conducted an empirical analysis for Tourism Region of South Anhui(TRSA) and revealed the necessity and feasibility of studying the roles and functions of destinations from tourist flow network's perspective.The automorphic equivalence analysis and centrality analysis were used to classify 16 destinations in TRSA into six role types:tourist flow distribution center,hub of tourist flows,passageway destination,common touring destination,attached touring destination,and nearly isolated destination.Some suggestions were given on suitable infrastructure construction and destinations service designs according to their functions in network.This destination role positioning was based on tourist flow network structure in integral and macroscopic way.It provided an important reference for the balanced and harmonious development of all the destinations of TRSA.In addition,this article verified the applicability of social network analysis on tourist flow research in local scale,and expanded this method to destination role and function positioning. 展开更多
关键词 网络功能 目的地 旅游区 职能 皖南 基础设施建设 空间结构 实证分析
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CLASSES OF MEROMORPHIC FUNCTIONS ASSOCIATED WITH CONIC REGIONS 被引量:2
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作者 J.Dziok 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期765-774,共10页
The object of this article is to introduce new classes of meromorphic functions associated with conic regions.Several properties like the coefficient bounds,growth and distortion theorems,radii of starlikeness and con... The object of this article is to introduce new classes of meromorphic functions associated with conic regions.Several properties like the coefficient bounds,growth and distortion theorems,radii of starlikeness and convexity,partial sums,are investigated.Some consequences of the main results for the well-known classes of meromorphic functions are also pointed out. 展开更多
关键词 亚纯函数 二次曲线 关联 凸半径 圆锥 定理
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