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Brain structure in post-traumatic stress disorder A voxel-based morphometry analysis
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作者 Liwen Tan Li Zhang +4 位作者 Rongfeng Qi Guangming Lu Lingjiang Li Jun Liu Weihui Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第26期2405-2414,共10页
This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experie... This study compared the difference in brain structure in 12 mine disaster survivors with chronic post-traumatic stress disorder, 7 cases of improved post-traumatic stress disorder symptoms, and 14 controls who experienced the same mine disaster but did not suffer post-traumatic stress disorder, using the voxel-based morphometry method. The correlation between differences in brain structure and post-traumatic stress disorder symptoms was also investigated. Results showed that the gray matter volume was the highest in the trauma control group, followed by the symptoms-improved group, and the lowest in the chronic post-traumatic stress disorder group. Compared with the symptoms-improved group, the gray matter volume in the lingual gyrus of the right occipital lobe was reduced in the chronic post-traumatic stress disorder group. Compared with the trauma control group, the gray matter volume in the right middle occipital gyrus and left middle frontal gyrus was reduced in the symptoms-improved group. Compared with the trauma control group, the gray matter volume in the left superior parietal lo- bule and right superior frontal gyrus was reduced in the chronic post-traumatic stress disorder group. The gray matter volume in the left superior parietal Iobule was significantly positively correlated with the State-Trait Anxiety Inventory subscale score in the symptoms-improved group and chronic post-traumatic stress disorder group (r = 0.477, P = 0.039). Our findings indicate that (1) chronic post-traumatic stress disorder patients have gray matter structural damage in the prefrontal lobe, oc- cipital lobe, and parietal lobe, (2) after post-traumatic stress, the disorder symptoms are improved and gray matter structural damage is reduced, but cannot recover to the trauma-control level, and (3) the superior parietal Iobule is possibly associated with chronic post-traumatic stress disorder. Post-traumatic stress disorder patients exhibit gray matter abnormalities. 展开更多
关键词 neural regeneration NEUROIMAGING MRI post-traumatic stress disorder voxel-based morphometry pre-frontal lobe parietal lobe occipital lobe follow-ups grants-supported paper NEUROREGENERATION
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Differences in brain structure in patients with distinct sites of chronic pain:A voxel-based morphometric analysis 被引量:7
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作者 Cuiping Mao Longxiao Wei +3 位作者 Qiuli Zhang Xia Liao Xiaoli Yang Ming Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第32期2981-2990,共10页
A reduction in gray matter volume is common in patients with chronic back pain, and different types of pain are associated with gray matter abnormalities in distinct brain regions. To examine differ- ences in brain mo... A reduction in gray matter volume is common in patients with chronic back pain, and different types of pain are associated with gray matter abnormalities in distinct brain regions. To examine differ- ences in brain morphology in patients with low back pain or neck and upper back pain, we investi- gated changes in gray matter volume in chronic back pain patients having different sites of pain using voxel-based morphometry. A reduction in cortical gray matter volume was found primarily in the left postcentral gyrus and in the left precuneus and bilateral cuneal cortex of patients with low back pain. In these patients, there was an increase in subcortical gray matter volume in the bilateral putamen and accumbens, right pallidum, right caudate nucleus, and left amygdala. In upper back pain patients, reduced cortical gray matter volume was found in the left precentral and left postcen- tral cortices. Our findings suggest that regional gray matter volume abnormalities in low back pain patients are more extensive than in upper back pain patients. Subcortical gray matter volume in- creases are found only in patients with low back pain. 展开更多
关键词 neural regeneration brain injury chronic low back pain upper back pain voxel-based morphometry gray matter magnetic resonance imaging basal ganglia ATROPHY chronic pain grants-supportedpaper NEUROREGENERATION
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White matter abnormalities in young males with antisocial personality disorder Evidence from voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis 被引量:1
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作者 Daxing Wu Ying Zhao +2 位作者 Jian Liao Huifang Yin Wei Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第25期1965-1970,共6页
Voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis was used to investigate the structural characteristics of white matter in young males with antisocial personality ... Voxel-based morphometry-diffeomorphic anatomical registration using exponentiated lie algebra analysis was used to investigate the structural characteristics of white matter in young males with antisocial personality disorder (APD) and healthy controls without APD. The results revealed that APD subjects, relative to healthy subjects, exhibited increased white matter volume in the bilateral prefrontal lobe, right insula, precentral gyrus, bilateral superior temporal gyrus, right postcentral gyrus, right inferior parietal Iobule, right precuneus, right middle occipital lobe, right parahippocampal gyrus and bilateral cingulate, and decreased volume in the middle temporal cortex and right cerebellum. The white matter volume in the medial frontal gyrus was significantly correlated with antisocial type scores on the Personality Diagnostic Questionnaire in APD subjects. These experimental findings indicate that white matter abnormalities in several brain areas may contribute to antisocial behaviors in APD subjects. 展开更多
关键词 white matter frontal lobe antisocial personality disorder voxel-based morphometry NEUROIMAGING
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Multimodal abnormalities of brain structures in adolescents and young adults with major depressive disorder:An activation likelihood estimation meta-analysis
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作者 Yan-Ping Shu Qin Zhang +4 位作者 Yong-Zhe Hou Shuang Liang Zu-Li Zheng Jia-Lin Li Gang Wu 《World Journal of Psychiatry》 SCIE 2024年第7期1106-1117,共12页
BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging ... BACKGROUND Major depressive disorder(MDD)in adolescents and young adults contributes significantly to global morbidity,with inconsistent findings on brain structural changes from structural magnetic resonance imaging studies.Activation likeli-hood estimation(ALE)offers a method to synthesize these diverse findings and identify consistent brain anomalies.METHODS We performed a comprehensive literature search in PubMed,Web of Science,Embase,and Chinese National Knowledge Infrastructure databases for neuroi-maging studies on MDD among adolescents and young adults published up to November 19,2023.Two independent researchers performed the study selection,quality assessment,and data extraction.The ALE technique was employed to synthesize findings on localized brain function anomalies in MDD patients,which was supplemented by sensitivity analyses.RESULTS Twenty-two studies comprising fourteen diffusion tensor imaging(DTI)studies and eight voxel-based morphome-try(VBM)studies,and involving 451 MDD patients and 465 healthy controls(HCs)for DTI and 664 MDD patients and 946 HCs for VBM,were included.DTI-based ALE demonstrated significant reductions in fractional anisotropy(FA)values in the right caudate head,right insula,and right lentiform nucleus putamen in adolescents and young adults with MDD compared to HCs,with no regions exhibiting increased FA values.VBM-based ALE did not demonstrate significant alterations in gray matter volume.Sensitivity analyses highlighted consistent findings in the right caudate head(11 of 14 analyses),right insula(10 of 14 analyses),and right lentiform nucleus putamen(11 of 14 analyses).CONCLUSION Structural alterations in the right caudate head,right insula,and right lentiform nucleus putamen in young MDD patients may contribute to its recurrent nature,offering insights for targeted therapies. 展开更多
关键词 Major depressive disorder ADOLESCENT Young adults NEUROIMAGING Diffusion tensor imaging voxel-based morphometry Activation likelihood estimation META-analysis
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Gray Matter Volume Changes over the Whole Brain in the Bulbar-and Spinal-onset Amyotrophic Lateral Sclerosis: a Voxel-based Morphometry Study 被引量:2
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作者 陈志晔 刘梦琦 马林 《Chinese Medical Sciences Journal》 CAS CSCD 2018年第1期20-28,共9页
Objective To investigate cerebral structural signatures of the bulbar-and spinal-onset amyotrophic lateral sclerosis(ALS) using voxel-based morphometry on magnetic resonance imaging.Methods The MR structural images of... Objective To investigate cerebral structural signatures of the bulbar-and spinal-onset amyotrophic lateral sclerosis(ALS) using voxel-based morphometry on magnetic resonance imaging.Methods The MR structural images of the brain were obtained from 65 ALS patients(15 bulbar-onset, 50 spinalonset) and 65 normal controls(NC) on a 3.0 T MRI system. Gray matter(GM) volume changes were investigated by voxel-based morphometry, and the distribution of the brain regions with volume changes was compared between ALS and normal controls, as well as between bulbar-onset and spinal-onset ALS based on Neuromorphometrics atlas.Results On voxel-level the decreased volume of brain regions in ALS patients was located in the right precentral gyrus(r Prc Gy) and right middle frontal gyrus compared with that in NC. The bulbar-onset ALS presented extramotor cortex atrophy(fronto-temporal pattern), including left medial orbital gyrus, left inferior temporal gyrus and right middle temporal gyrus; the spinal-onset ALS suffered from motor cortex atrophy(r Prc Gy dominance) and extra-motor cortex atrophy(fronto-temporal and extra-fronto-temporal pattern) compared with NC. The spinal-onset ALS featured by GM volume loss of left postcentral gyrus and bulbar-onset ALS featured by GM volume loss of left middle temporal gyrus compared with each other. Conclusions The asymmetric GM atrophy of the motor cortex and extra-motor cortex represents the common MRI structural signatures of spinal-onset ALS, and sole extra-motor cortex atrophy represents the structural signatures of bulbar-onset ALS. The present study also demonstrated that the pattern of GM damage is likely to distribute wider in spinal-onset ALS than in bulbar-onset ALS. 展开更多
关键词 amyotrophic lateral SCLEROSIS GRAY matter magnetic resonance imaging precentral GYRUS voxel-based morphometry
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Regional gray matter abnormality in hepatic myelopathy patients after transjugular intrahepatic portosystemic shunt: a voxel-based morphometry study 被引量:11
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作者 Kang Liu Gang Chen +9 位作者 Shu-Yao Ren Yuan-Qiang Zhu Tian-Lei Yu Ping Tian Chen Li Yi-Bin Xi Zheng-Yu Wang Jian-Jun Ye Guo-Hong Han Hong Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第5期850-857,共8页
Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain moto... Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014. 展开更多
关键词 portosystemic shunt HEPATIC MYELOPATHY HEPATIC ENCEPHALOPATHY magnetic resonance imaging gray matter lower limb FUGL-MEYER Assessment basal GANGLIA CAUDATE nucleus voxel-based morphometry
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Morphometric Analysis of Drainage Basins in the Western Arabian Peninsula Using Multivariate Statistics 被引量:4
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作者 Ali P. Yunus Takashi Oguchi Yuichi S. Hayakawa 《International Journal of Geosciences》 2014年第5期527-539,共13页
The uplift of the Arabian Shield and the opening of the Red Sea led to the development of steep drainage systems in the Western Arabian Peninsula. Although the Peninsula has been studied from a geological perspective,... The uplift of the Arabian Shield and the opening of the Red Sea led to the development of steep drainage systems in the Western Arabian Peninsula. Although the Peninsula has been studied from a geological perspective, in relation to oil production, plate tectonics and eolian systems such as sand dunes, the steep mountainous drainage basins have received much less attention. This paper aims to assess the characteristics and development of 36 drainage basins in the Western Arabian Peninsula, using a digital elevation model (DEM), principal component analysis (PCA), and hierarchical cluster analysis (CA). Three major principal components (PC1 to PC3) are found to explain 73% of total variance. CA divided the basins into two or four groups. The division by CA strongly reflects PC1, showing that the two analyses give comparable results. PC1 strongly reflects basin dimensions and drainage texture, and their positive correlations indicate the significant effect of basin relief and slope on mass wasting and limited stream incision in small basins under an arid climate. PC2 mainly reflects the effect of bedrock geology, suggesting that volcanic rocks tend to produce more elongated and less eroded immature basins than crystalline rocks do. PC3 mainly reflects the basin relief and slope and the length of each stream segment, which may also reflect the effect of mass wasting on stream development. 展开更多
关键词 Arabian PENINSULA Drainage Basin Digital ELEVATION Model morphometry Principal Component analysis Cluster analysis
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Regional brain structural abnormality in ischemic stroke patients:a voxel-based morphometry study 被引量:3
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作者 Ping Wu Yu-mei Zhou +14 位作者 Fang Zeng Zheng-jie Li Lu Luo Yong-xin Li Wei Fan Li-hua Qiu Wei Qin Lin Chen Lin Bai Juan Nie San Zhang Yan Xiong Yu Bai Can-xin Yin Fan-rong Liang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第9期1424-1430,共7页
Our previous study used regional homogeneity analysis and found that activity in some brain areas of patients with ischemic stroke changed significantly. In the current study, we examined structural changes in these b... Our previous study used regional homogeneity analysis and found that activity in some brain areas of patients with ischemic stroke changed significantly. In the current study, we examined structural changes in these brain regions by taking structural magnetic resonance imaging scans of 11 ischemic stroke patients and 15 healthy participants, and analyzing the data using voxel-based morphometry. Compared with healthy participants, patients exhibited higher gray matter density in the left inferior occipital gyrus and right anterior white matter tract. In contrast, gray matter density in the right cerebellum, left precentral gyrus, right middle frontal gyrus, and left middle temporal gyrus was less in ischemic stroke patients. The changes of gray matter density in the middle frontal gyrus were negatively associated with the clin- ical rating scales of the Fugl-Meyer Motor Assessment (r = -0.609, P = 0.047) and the left middle temporal gyrus was negatively correlated with the clinical rating scales of the nervous functional deficiency scale (r = -0.737, P = 0.010). Our findings call objectively identify the functional abnormality in some brain regions of ischemic stroke patients. 展开更多
关键词 nerve regeneration ischemic stroke brain structure abnormality Junctional magnetic resonance imaging gray matter density voxel-based morphometry Fugl-Meyer Motor Assessment nervous fi^nctional deficiency scale functional deficiency NEUROPLASTICITY neuralreorganization neural regeneration
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Regionalization of epididymal duct and epithelium in rats and mice by automatic computer-aided morphometric analysis
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作者 C.Soler J.J.deMonserrat +4 位作者 M.Núez R.Gutiérrez J.Núez M.Sancho T.G.Cooper 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第3期267-275, ,共9页
Aim: To establish a rat and mouse epididymal map based on the use of the Epiquatre automatic software for histologic image analysis. Methods: Epididymides from five adult rats and five adult mice were fixed in alcoh... Aim: To establish a rat and mouse epididymal map based on the use of the Epiquatre automatic software for histologic image analysis. Methods: Epididymides from five adult rats and five adult mice were fixed in alcoholic Bouin's fixative and embedded in paraffin. Serial longitudinal sections through the medial aspect of the organ were cut at 10 jam and stained with hematoxylin and eosin. As determined from major connective tissue septa, nine subdivisions of the rat epididymis and seven for the mouse were determined, consisting of five sub-regions in the caput (rat and mouse), one (mouse) or three (rat) in the corpus and one in the cauda (rat and mouse). Using the Epiquatre software, several tubular, luminal and epithelial morphometric parameters were evaluated. Results: Statistical comparison of the quantitative parameters revealed regional differences (2-5 in the rat, 3-6 in the mouse, dependent on parameters) with caput regions 1 and 2 being largely distinguishable from the similar remaining caput and corpus, which were in turn recognizable from the cauda regions in both species. Conclusion: The use of the Epiquatre software allowed us to establish regression curves for different morphometric parameters that can permit the detection of changes in their values under different pathological or experimental conditions. (Asian J Androl 2005 Sep; 7: 267-275) 展开更多
关键词 rat mouse EPIDIDYMIS morphometry ZONATION computer-aided image analysis Epiquatre Software
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Quantitative Analysis of Geomorphometric Parameters of Wadi Kerak, Jordan, Using Remote Sensing and GIS
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作者 Yahya Farhan Ali Anbar +1 位作者 Omar Enaba Nisrin Al-Shaikh 《Journal of Water Resource and Protection》 2015年第6期456-475,共20页
Geomorphometric analysis was carried out to illustrate the drainage characteristics and morphology of Wadi Kerak watershed, southern Jordan. The basic and derived morphometric parameters (linear, areal and relief aspe... Geomorphometric analysis was carried out to illustrate the drainage characteristics and morphology of Wadi Kerak watershed, southern Jordan. The basic and derived morphometric parameters (linear, areal and relief aspects of drainage network) for the basin were determined using ASTER DEM (30 m resolution) and Geographic Information System (GIS). These parameters describe the basin drainage network, geometry, texture, and relief characteristics. The hypsometric curve, hypsometric integral and clinographic curve were also prepared using topographic maps of 1:50,000 scale. Findings have revealed that W. Kerak is in the youth-age stage of geomorphic evolution. Fluvial erosion associated with successive phases of rejuvenation plays a significant role in drainage basin development, whereas structure and tectonics, lithology and relief dictate the drainage pattern and morphological setting of the catchment. The drainage area of the watershed is 190.9 km2 and constitutes a 5th-order drainage basin. The commonly observed drainage patterns are the trellis type, with sub-dendritic pattern recognized in the upper catchment. The drainage pattern, and the semi-linear alignment of main and branching drainage indicate the prominent influence of the Kerak-Al-fiha fault system on the drainage network. High dissection, relative relief, relief ratio, steep slopes and breaks of slopes are characteristic of W. Kerak. Morphometric analysis reveals that four rejuvenation phases caused severe erosion and down cutting activity in the past, and it is still susceptible to surface erosion at present. 展开更多
关键词 ASTER DEM Drainage morphometry DISSECTION Index REJUVENATION Hypsometric analysis Clinographic Curve
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Voxel-Based Morphometric Study on Chinese Blind Men's Brain Structure
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作者 杨春兰 潘文举 郑链 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期56-60,共5页
Many studies have shown the functional relevance of cross-modal plasticity in blind men. In order to study the changes of their brain structure, voxel-based morphometry (VBM) methods are used. The regional gray matt... Many studies have shown the functional relevance of cross-modal plasticity in blind men. In order to study the changes of their brain structure, voxel-based morphometry (VBM) methods are used. The regional gray matter (GM) and white matter (WM) concentrations of magnetic resonance (MR) images from 11 blind people and 9 sighted control subjects are compared using standard VBM. Optimized VBM is also discussed to measure the absolute local volume of GM or WM. Consistent results are achieved by statistical analysis with these methods. There are distinct differences not only in visual cortex but also the sensory area, auditory area and motor area. GM concentrations in blind men significantly decreased in Brodmann 7 and 22. While in Brodmann 18 and 19, GM concentration increased. GM volumes decreased in Brodmann 3, 4, 6, 9 and 45. On the other hand, both WM concentration and volume increased in Brodmann 7. These results suggest that early visual deprivation can lead to changes in the brain structural anatomy which is consistent with the cortical cross-modal reorganization found by functional imaging. It may help to discover the relationship between the brain structural anatomy and the brain functional data of blind men at a macroscopic level from neuroimaging perspective. 展开更多
关键词 blind men brain structure voxel-based morphometry
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Application of voxel-based morphometric method to detect brain changes in children with non-cyanotic congenital heart disease
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作者 Xuan Jia Xiao-Hui Ma Jia-Wei Liang 《World Journal of Radiology》 CAS 2020年第9期204-212,共9页
BACKGROUND Congenital heart disease(CHD)is a cardiovascular malformation caused by abnormal heart and/or vascular development in the fetus.In children with CHD,abnormalities in the development and function of the nerv... BACKGROUND Congenital heart disease(CHD)is a cardiovascular malformation caused by abnormal heart and/or vascular development in the fetus.In children with CHD,abnormalities in the development and function of the nervous system are common.At present,there is a lack of research on the preoperative neurological development and injury in young children with non-cyanotic CHD.AIM To determine the changes in white matter,gray matter,and cerebrospinal fluid(CSF)by magnetic resonance imaging(MRI)in children with non-cyanotic CHD as compared with healthy controls.METHODS Children diagnosed with non-cyanotic CHD on ultrasonography(n=54)and healthy control subjects(n=35)were included in the study.All the subjects were aged 1-3 years.Brain MRI was performed prior to surgery for CHD.The SPM v12 software was used to calculate the volumes of the gray matter,white matter,CSF,and the whole brain(sum of the gray matter,white matter,and CSF volumes).Volume differences between the two groups were analyzed.Voxel-based morphometry was used to compare specific brain regions with statistically significant atrophy.RESULTS Compared with the control group,the study group had significantly reduced whole-brain white matter volume(P<0.05),but similar whole-brain gray matter,CSF,and whole-brain volumes(P>0.05).As compared with the healthy controls,children with non-cyanotic CHD had mild underdevelopment in the white matter of the anterior central gyrus,the posterior central gyrus,and the pulvinar.CONCLUSION Children with non-cyanotic CHD show decreased white matter volume before surgery,and this volume reduction is mainly concentrated in the somatosensory and somatic motor nerve regions. 展开更多
关键词 voxel-based morphometry Non-cyanotic congenital heart disease Young children Magnetic resonance imaging
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GIS-Based Morphometric Analysis of Fourth-Order Sub-Basins of the Zerqa River (Northern Jordan) Using Multivariate Statistical Techniques
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作者 Yahya Farhan Ibtisam Elmaji Osama Khalil 《Natural Resources》 2016年第8期461-480,共20页
The present study attempts to examine the morphometric characteristics and relationships of 43 fourth-order sub-basins over the Zerqa River watershed, using ASTER DEM, GIS and multivariate statistics. To achieve these... The present study attempts to examine the morphometric characteristics and relationships of 43 fourth-order sub-basins over the Zerqa River watershed, using ASTER DEM, GIS and multivariate statistics. To achieve these objectives, Principal Component Analysis was utilized to reduce the 26 parameters into six major components which accounted for 79.3% of the total variance explained by the original morphometric variables. Hierarchical Cluster Analysis (CA) (Ward’s method) has been applied to classify the 43 sub-basins based on different types of morphometric parameters. Four groups of sub-watersheds were identified and characterized by different morphometric properties. The patterns of spatial distribution of cluster groups were determined based on lithological, structure and tectonics, uplifting, and rejuvenation processes. 展开更多
关键词 morphometry ASTER DEM Principal Component analysis Cluster analysis Zerqa River JORDAN
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Prioritization of Sub-Watersheds in Ruparel Watershed, Rajasthan Based on Morphometric and Land Use/Land Cover Analysis Using Remote Sensing and GIS
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作者 Munahzah Meraj Akram Javed 《International Journal of Geosciences》 2022年第2期138-154,共17页
Watershed prioritization is considered as the most significant aspect in watershed resource management and development program. The present work attempts to prioritize seventeen sub-watersheds in Ruparel watershed of ... Watershed prioritization is considered as the most significant aspect in watershed resource management and development program. The present work attempts to prioritize seventeen sub-watersheds in Ruparel watershed of Alwar district of Rajasthan, India. For prioritization of sub-watersheds, morphometric and land use/land cover (LULC) analysis were performed using remote sensing and GIS. Base map of the study area has been derived from SOI toposheet on 1:50,000 scale whereas LULC mapping was done using IRS P6 LISS III data. Standard methods for drainage morphometry have been followed for computing morphometric parameters such as linear and shape for seventeen sub-watersheds and allotted ranks based on their relationship with erodibility and a compound value has been calculated for final ranking. Five main LULC categories were computed and were assigned priority ranks and subsequently a compound parameter was determined for final ranking. Integration of both morphometric and LULC results reveal that SBW5, SBW7, SBW12 and SBW16 are the common sub-watersheds that fall under high priority, SBW3 falls under Medium category and SBW11 comes under low priority. The results of the analysis can be used to identify the sub-watersheds which need immediate restoration and will eventually help in watershed resource management for sustainable development. 展开更多
关键词 PRIORITIZATION Watershed Resource Management morphometry Land Use/Land Cover analysis
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Abnormal volumetric brain morphometry and cerebral blood flow in adolescents with depression 被引量:2
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作者 Yu-Jia Fu Xiao Liu +6 位作者 Xing-Yu Wang Xiao Li Lin-Qi Dai Wen-yu Ren Yong-Ming Zeng Zhen-Lin Li Ren-Qiang Yu 《World Journal of Psychiatry》 SCIE 2023年第6期386-396,共11页
BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain b... BACKGROUND Prior research has demonstrated that the brains of adolescents with depression exhibit distinct structural alterations.However,preliminary studies have documented the pathophysiological changes in certain brain regions,such as the cerebellum,highlighting a need for further research to support the current understanding of this disease.AIM To study brain changes in depressed adolescents.METHODS This study enrolled 34 adolescents with depression and 34 age-,sex-,and education-level-matched healthy control(HC)individuals.Structural and functional alterations were identified when comparing the brains of these two participant groups through voxel-based morphometry and cerebral blood flow(CBF)analysis,respectively.Associations between identified brain alterations and the severity of depressive symptoms were explored through Pearson correlation analyses.RESULTS The cerebellum,superior frontal gyrus,cingulate gyrus,pallidum,middle frontal gyrus,angular gyrus,thalamus,precentral gyrus,inferior temporal gyrus,superior temporal gyrus,inferior frontal gyrus,and supplementary motor areas of adolescents with depression showed an increase in brain volume compared to HC individuals.These patients with depression further presented with a pronounced drop in CBF in the left pallidum(group=98,and peak t=-4.4324),together with increased CBF in the right percental gyrus(PerCG)(group=90,and peak t=4.5382).In addition,17-item Hamilton Depression Rating Scale scores were significantly correlated with the increased volume in the opercular portion of the left inferior frontal gyrus(r=-0.5231,P<0.01).CONCLUSION The right PerCG showed structural and CBF changes,indicating that research on this part of the brain could offer insight into the pathophysiological causes of impaired cognition. 展开更多
关键词 voxel-based morphometry Cerebral blood flow Arterial spin labeling ADOLESCENT DEPRESSION The right percental gyrus
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西沙群岛鹦嘴鱼科耳石形态学物种鉴定的可行性研究
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作者 康志鹏 李纯厚 +4 位作者 李纯然 王腾 赵金发 石娟 刘永 《水生生物学报》 CAS CSCD 北大核心 2024年第3期469-478,共10页
研究于2018—2021年在西沙群岛海域采集鹦嘴鱼样本,通过传统形态测量法选取的19个耳石形态指标和椭圆傅里叶分析法选取的77个椭圆傅里叶系数对其进行鉴别分析,探究耳石形态在鹦嘴鱼科物种鉴别中的可行性。结果表明,仅使用耳石形态指标... 研究于2018—2021年在西沙群岛海域采集鹦嘴鱼样本,通过传统形态测量法选取的19个耳石形态指标和椭圆傅里叶分析法选取的77个椭圆傅里叶系数对其进行鉴别分析,探究耳石形态在鹦嘴鱼科物种鉴别中的可行性。结果表明,仅使用耳石形态指标鉴别鹦嘴鱼时综合判别率为56.8%,低于仅使用椭圆傅里叶系数的63.1%和两种参数结合的75.7%;而结合两种参数对其4个属的综合判别率为88.6%,其中绚鹦嘴鱼属的判别率达到100%;15种鹦嘴鱼的耳石形态聚类结果与已有研究的进化树结果基本一致,特别是属层面的聚类,呈现高度一致,证实了耳石形态具有遗传的属性,也说明了耳石形态学用于鱼类物种鉴定的可行性。研究结果将为西沙群岛鹦嘴鱼的基础研究提供科学资料,为鹦嘴鱼资源的保护与开发提供理论依据。 展开更多
关键词 耳石形态 传统形态测量法 椭圆傅里叶分析法 鹦嘴鱼
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基于ALE的面肌痉挛功能和结构异常脑区的Meta分析
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作者 郎栩 李兵 +3 位作者 李泓箭 周慧玲 孙白瑾涛 杨汉丰 《中国CT和MRI杂志》 2024年第10期19-22,共4页
目的 通过荟萃分析探讨原发性面肌痉挛(hemifacial spasm,HFS)患者脑功能和结构的改变特点,进一步了解HFS的病理生理机制。方法收集2023年4月之前发表在相关数据库中关于HFS患者静息态功能磁共振成像(rest-state functional Magnetic re... 目的 通过荟萃分析探讨原发性面肌痉挛(hemifacial spasm,HFS)患者脑功能和结构的改变特点,进一步了解HFS的病理生理机制。方法收集2023年4月之前发表在相关数据库中关于HFS患者静息态功能磁共振成像(rest-state functional Magnetic resonance imaging,Rs-fMRI)和基于体素的形态学分析方法(voxel-based morphometry,VBM)的所有文章。根据纳入和排除标准筛选后,采用激活似然估计(activation likelihood estimation,ALE)方法进行meta分析。结果共纳入7篇文献、10项研究(原发性面肌痉挛患者315例,健康受试者315名),对低频振荡幅度(amplitude of low frequency fluctuation,ALFF)、低频振荡分数(Fractional amplitude of low-frequency fluctuation,fALFF)及局部一致性(regional homogeneity,ReHo)等RsfMRI指标进行功能分析。ALE-meta结果显示,相对于健康受试者,HFS患者的自发性脑功能活动在中央前回、后扣带回、脑桥及小脑显著升高,而在额中回及颞上回降低。将所有基于VBM的HFS患者灰质改变的文献进行结构分析,结果显示,相对于健康受试者,HFS患者的海马旁回、丘脑体积显著减小。结论HFS患者存在脑功能和结构的改变,主要表现为中央前回、脑桥、小脑和后扣带回脑区自发性脑功能活动的异常,以及突显网络结构的异常,初步阐明了HFS患者静息态脑功能活动及结构改变的规律及特征。 展开更多
关键词 面肌痉挛 静息态功能磁共振成像 形态学 META分析
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Nuclear morphometry, nucleomics and prostate cancer progression 被引量:2
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作者 Robert W Veltri Christhunesa S Christudass Sumit Isharwal 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第3期375-384,I0005,共11页
Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instabil... Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instability through reactive oxygen species causing DNA double-strand breaks), followed by a multistep process of progression. These steps include several genetic and epigenetic alterations, as well as alterations to the chromatin structure, which occur in response to the carcinogenic stress-related events that sustain proliferative signaling. Events such as evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis are readily observed. In addition, in conjunction with these critical drivers of carcinogenesis, other factors related to the etiopathogenesis of PCa, involving energy metabolism and evasion of the immune surveillance system, appear to be involved. In addition, when cancer spread and metastasis occur, the 'tumor microenvironment' in the bone of PCa patients may provide a way to sustain dormancy or senescence and eventually establish a 'seed and soil' site where PCa proliferation and growth may occur over time. When PCa is initiated and progression ensues, significant alterations in nuclear size, shape and heterochromatin (DNA transcription) organization are found, and key nuclear transcriptional and structural proteins, as well as multiple nuclear bodies can lead to precancerous and malignant changes. These series of cellular and tissue-related malignancy-associated events can be quantified to assess disease progression and management. 展开更多
关键词 active surveillance cancer metastasis cancer progression digital image analysis molecular biomarkers morphologicalbiomarkers nuclear morphometry nuclear proteins and nuclear structure prostate cancer
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Assessment of Morphometric Characteristics of Wadi Al-Shumar Catchment in Jordan 被引量:1
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作者 Zeyad Makhamreh Mohammad Al-Hawary Samih Odeh 《Open Journal of Geology》 2020年第2期155-170,共16页
The Geographic information system and Aster DEM data with 30 m resolution have been used for the derivation of the morphometric parameters of the Al-Shumar watershed in Jordan. It is an area of 330 km2, and it has sev... The Geographic information system and Aster DEM data with 30 m resolution have been used for the derivation of the morphometric parameters of the Al-Shumar watershed in Jordan. It is an area of 330 km2, and it has seven sub-catchments. The drainage pattern of the watershed shows a dendritic and parallel pattern, with a drainage density value of 1.49 - 1.85 km/km2. The bifurcation value of the sub-watersheds varies from 2.679 to 4.434, which reveals homogeneous drainage networks that formed on rocks when the influence of geologic structure on the stream network is negligible. The form factor value is near the rectangular shape except for the Al-Shiah and Al-Zarnouk watershed, these values are close to the circular shape and therefore they are vulnerable to flood risk in case of frequent rainfall events. The results are important in understanding the process of rainfall-runoff in Dryland environments and in adaptation of suitable water management practices on the sub-catchment level. 展开更多
关键词 River morphometry DEM GIS analysis DRYLAND Regions JORDAN
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Magnetic resonance morphometry of the loss of gray matter volume in Parkinson's disease patients 被引量:1
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作者 Jianguo Xia Juan Wang +7 位作者 Weizhong Tian Hongbin Ding Qilin Wei Huanxin Huang Jun Wang Jinli Zhao Hongmei Gu Lemin Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第27期2557-2565,共9页
Voxel-based morphometry can be used to quantitatively compare structural differences and func-tional changes of gray matter in subjects. In the present study, we compared gray matter images of 32 patients with Parkin... Voxel-based morphometry can be used to quantitatively compare structural differences and func-tional changes of gray matter in subjects. In the present study, we compared gray matter images of 32 patients with Parkinson’s disease and 25 healthy controls using voxel-based morphometry based on 3.0 T high-field magnetic resonance T1-weighted imaging and clinical neurological scale scores. Results showed that the scores in Mini-Mental State Examination and Montreal Cognitive Assessment were lower in patients compared with controls. In particular, the scores of visuospatial/executive function items in Montreal Cognitive Assessment were significantly reduced, but mean scores of non-motor symptoms significantly increased, in patients with Parkinson’s dis-ease. In addition, gray matter volume was significantly diminished in Parkinson’s disease patients compared with normal controls, including bilateral temporal lobe, bilateral occipital lobe, bilateral parietal lobe, bilateral frontal lobe, bilateral insular lobe, bilateral parahippocampal gyrus, bilateral amygdale, right uncus, and right posterior lobe of the cerebel um. These findings indicate that voxel-based morphometry can accurately and quantitatively assess the loss of gray matter volume in patients with Parkinson's disease, and provide essential neuroimaging evidence for multisystem pathological mechanisms involved in Parkinson’s disease. 展开更多
关键词 neural regeneration NEUROIMAGING NEURODEGENERATION voxel-based morphometry Parkinson'sdisease MRI dopamine non-motor symptoms gray matter abnormality region of interest Mini-Mental State Examination Montreal Cognitive Assessment neurodegenerative disease grants-supported paper NEUROREGENERATION
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