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1.
Heliyon ; 10(3): e25047, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318075

RESUMO

Spatial association rule mining can reveal the inherent laws of spatial object interdependence and is an important part of spatial data mining. Most of the existing algorithms for mining local spatial association rules are oriented towards the spatial association between two categories of points and cannot fully reflect the spatial heterogeneity of complex spatial relations among multiple categories of points. In addition, the interactions between points in different categories are often asymmetrical. However, the existing algorithms ignore this asymmetry. To address the above problems, an algorithm for mining local spatial association rules for point data of multiple categories based on position quotients is proposed. First, the proximity relationship between points is determined by an adaptive filter, and the spatial weight value is given according to Gaussian kernel function. Then, the multivariate local colocation quotient of each point is calculated to measure the strength of the local regional spatial association rule. Finally, the Monte Carlo simulation function is used to generate a random sample distribution to test the significance of the results. The algorithm is verified on artificial simulation data and real Point of Interest (POI) data. The experimental results show that the algorithm can identify significant association regions of different spatial association rules for point sets.

2.
Environ Res ; 234: 116469, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37394173

RESUMO

Promoting ecological conservation and high-quality development in the Yellow River basin is an important objective in China's 14th Five-Year Plan. Understanding the spatio-temporal evolution of and factors affecting the resources and environmental carrying capacity (RECC) of the urban agglomerations is critical for boosting high-quality green-oriented development. We first combined the Driver-Pressure-State-Impact-Response (DPSIR) framework and the improved Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) model to evaluate the RECC of Shandong Peninsula urban agglomeration in 2000, 2010 and 2020; we then used trend analysis and spatial autocorrelation analysis to understand the spatio-temporal evolution and distribution pattern of RECC. Furthermore, we employed Geodetector to detect the influencing factors and classified the urban agglomeration into six zones based on the weighted Voronoi diagram of RECC as well as specific conditions of the study area. The results show that the RECC of Shandong Peninsula urban agglomeration increased consistently over time, from 0.3887 in 2000 to 0.4952 in 2010 and 0.6097 in 2020, respectively. Geographically, RECC decreased gradually from the northeast coast to the southwest inland. Globally, only in 2010 the RECC presented a significant spatial positive correlation, and that in the other years were not significant. The high-high cluster was mainly located in Weifang, while the low-low cluster in Jining. Furthermore, our study reveals three key factors-advancement of industrial structure, resident consumption level, and water consumption per ten thousand yuan of industrial added value-that affected the distribution of RECC. Other factors, including the interactions between residents' consumption level and environmental regulation, residents' consumption level and advancement of industrial structure, as well as between the proportion of R&D expenditure in GDP and resident consumption level also played important roles resulting in the variation of RECC among different cities within the urban agglomeration. Accordingly, we proposed suggestions for achieving high-quality development for different zones.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Econômico , Cidades , Análise Espacial , Indústrias , China , Rios , Urbanização
3.
Opt Express ; 31(12): 19646-19656, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381375

RESUMO

Plasmonic nanoparticles can be employed as a promising integrated platform for lumped optical nanoelements with unprecedentedly high integration capacity and efficient nanoscale ultrafast nonlinear functionality. Further minimizing the size of plasmonic nanoelements will lead to a rich variety of nonlocal optical effects due to the nonlocal nature of electrons in plasmonic materials. In this work, we theoretically investigate the nonlinear chaotic dynamics of the plasmonic core-shell nanoparticle dimer consisting of a nonlocal plasmonic core and a Kerr-type nonlinear shell at nanometer scale. This kind of optical nanoantennae could provide novel switching functionality: tristable, astable multivibrators, and chaos generator. We give a qualitative analysis on the influence of nonlocality and aspect ratio of core-shell nanoparticles on the chaos regime as well as on the nonlinear dynamical processing. It is demonstrated that considering nonlocality is very important in the design of such nonlinear functional photonic nanoelements with ultra-small size. Compared to solid nanoparticles, core-shell nanoparticles provide an additional freedom to adjust their plasmonic property hence tuning the chaotic dynamic regime in the geometric parameter space. This kind of nanoscale nonlinear system could be the candidate for a nonlinear nanophotonic device with a tunable nonlinear dynamical response.

4.
Front Neurosci ; 17: 1195725, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123366

RESUMO

[This corrects the article DOI: 10.3389/fnins.2023.1139086.].

5.
Front Neurosci ; 17: 1139086, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008219

RESUMO

Aim: Structural and functional changes in the brain have been identified in individuals with medication-overuse headache (MOH) using MRI. However, it has not been clearly established whether neurovascular dysfunction occurs in MOH, which could be elucidated by examining neurovascular coupling (NVC) from the viewpoints of neuronal activity and cerebral blood flow. The aim of this study was to investigate potential alterations in NVC function of the brain in individuals with MOH using resting-state functional MRI (rs-fMRI) and 3D pseudo-continuous arterial spin labeling (3D PCASL) imaging techniques. Methods: A total of 40 patients with MOH and 32 normal controls (NCs) were recruited, and rs-fMRI and 3D PCASL data were obtained using a 3.0 T MR scanner. Standard preprocessing of the rs-fMRI data was performed to generate images representing regional homogeneity (ReHo), fractional amplitude of low-frequency fluctuation (fALFF), and degree centrality (DC); cerebral blood flow (CBF) images were generated using 3D PCASL sequence data. These functional maps were all normalized into Montreal Neurological Institute (MNI) space, and NVC was subsequently determined on the basis of Pearson correlation coefficients between the rs-fMRI maps (ReHo, fALFF, and DC) and CBF maps. The statistical significance of differences between the MOH and NC groups in terms of NVC in different brain regions was established via Z-test. Further analysis was performed to examine correlations between NVC in the brain regions with NVC dysfunction and clinical variables among patients with MOH. Results: NVC mainly presented a negative correlation in patients with MOH and NCs. No significant difference between the two groups was detected in terms of average NVC over the entire gray matter area. However, several brain regions with significantly decreased NVC in patients with MOH compared to NCs were identified: the left orbital region of the superior frontal gyrus, the bilateral gyrus rectus, and the olfactory cortex (P < 0.05). A correlation analysis revealed that the DC of the brain regions with NVC dysfunction was significantly positively correlated with disease duration (r = 0.323, P = 0.042), and DC-CBF connectivity was negatively correlated with VAS score (r = -0.424, P = 0.035). Conclusion: The current study demonstrated that cerebral NVC dysfunction occurs in patients with MOH, and the NVC technique could function as a new imaging biomarker in headache research.

6.
Chemistry ; 29(31): e202300206, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-36938659

RESUMO

In this paper, a waxberry-like MnS/Ni3 S4 composite catalyst was designed and synthesized. In this coating structure, MnS is located inside and Ni3 S4 is wrapped on the surface to form a spherical structure. This structure makes the material show excellent stability in the electrocatalytic process. The diffusion staggered region structure formed at the two-phase interface greatly enhances the synergistic interaction between MnS and Ni3 S4 . At the same time, the defects and vacancies formed by the diffusion mechanism at the interface of the two phases increase the active site and improve the interfacial electron transfer kinetics. Therefore, MnS/Ni3 S4 composites showed good catalytic performance for ORR/OER. At 10 mA cm-2 , the overpotential of it is only 320 mV, and the half-wave potential can reach 0.81 V. The catalyst also exhibited extraordinary cycle stability and small voltage gap when used as cathode of Zn-air batteries. When the current density is 3 mA cm-2 , the cyclic discharge can be stable for 400 h and the voltage difference between the front and back does not increase more than. When the current density increases to 5 mA cm-2 , the cyclic charge and discharge can be stable for more than 300 h.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34205325

RESUMO

Patients might be willing to pay more to obtain better quality medical services when they recognize that high-level hospitals have better quality. However, published papers have not found solid empirical evidence to support this possibility. Therefore, the purpose of this study is to empirically investigate patients' willingness to pay (WTP) for an outpatient copayment. The study aims to analyze the difference between the two WTP values: to implement a hierarchy of medical care and to improve the quality of medical services. This study administered a questionnaire using the contingent valuation method with a quasi-bidding game for patients' WTP and the SERVQUAL scale for medical service quality. The Wilcoxon signed-rank test was employed to test the difference between the two WTP values, notably to implement a hierarchy of medical care and to improve the quality of medical services. Both of the WTP values are higher than the academic medical centre's current copayment NT$420 (approximately US$14); the percentage of respondents willing to pay a higher copayment declined when the outpatient copayment was increased, and the patients' WTP to have better medical service quality was significantly higher than that to implement a hierarchy of medical care. Patients' desire to receive better medical services from higher-level hospitals might be stronger than their desire to implement hierarchical medical care. This study reported the relationship between the respondents' perceived medical service quality and WTP for having better service quality by using regression models. The respondents' perceptions of medical service quality, especially for "reliability" and "assurance," would positively affect their WTP. Policy makers should focus on improving the quality of medical services.


Assuntos
Financiamento Pessoal , Pacientes Ambulatoriais , Serviços de Saúde , Humanos , Inquéritos e Questionários , Taiwan
8.
Curr Med Imaging ; 17(7): 889-896, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33357199

RESUMO

BACKGROUND: Callosal Angle (CA) and Evans Index (EI) are considered as imaging biomarkers to diagnose normal-pressure hydrocephalus using traditional MR measurement methods. OBJECTIVE: The current study aimed to evaluate the differential diagnostic value of CA and EI in Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD). METHODS: Five-hundred and two subjects were selected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, which included 168 Normal Controls (NC), 233 MCI and 101 AD patients. The structural MR images were interactively applied with multiplanar reconstruction to measure the CA and EI. RESULTS: CA presented no significant difference among NC, MCI and AD groups (H value = 3.848, P value = 0.146), and EI demonstrated higher value in MCI and AD groups than that in NC groups (P = 0.000 and 0.001, respectively). MCI group had significant larger EI (0.29±0.04) than (0.27±0.03) NC group in 70-75 years old sub-groups. ROC showed that the area under the curve was 0.704±0.045 for NC-MCI in 70-75 years old groups. The correlation analysis indicated that EI was significantly negatively related to MMSE scores of MCI patients (r = -0.131, P = 0.046). CONCLUSION: EI might serve as a screening imaging biomarker for MCI in 70-75 years old patients, and show limited differential value for the diagnosis of AD. CA could present no diagnostic value for MCI and AD in the current study.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/diagnóstico , Biomarcadores , Disfunção Cognitiva/diagnóstico , Corpo Caloso/diagnóstico por imagem , Humanos , Neuroimagem
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(12): 1810-1815, 2020 Dec 30.
Artigo em Chinês | MEDLINE | ID: mdl-33380400

RESUMO

OBJECTIVE: To investigate the intra- and inter-scanner reproducibility of quantitative susceptibility mapping (QSM) of cerebral subcortical nuclei in healthy adults. METHODS: QSM was performed in 21 healthy adults on two different 3.0T MR scanners, and the region of interest (ROI) method was used to measure the magnetic susceptibility value of the left subcortical nuclei (the head of the caudate, putamen, globus pallidus, thalamus, substantia nigra and red nucleus). The intraclass correlation coefficient (ICC) and Bland-Altman method were used to evaluate the inter-scanner and intra-scanner reliability. RESULTS: The ICCs of the susceptibility value ranged from 0.90 to 0.99 for all the subcortical gray nuclei except for the head of the caudate nucleus measured on the same MR scanner by the same observer. Bland-Altman analysis revealed that the points with susceptibility differences for all the subcortical gray nuclei except for substantia nigra located in the 95% CI of limits of agreement for the same MR scanner. The ICCs of the susceptibility value for the inter-scanner was 0.49 (0.08-0.75) for the head of the caudate nuleus, 0.80 (0.57-0.91) for the putamen, 0.77 (0.51-0.90) for the globus pallidus, 0.78 (0.54-0.91) for the thalamus, 0.80 (0.56-0.91) for the substantia nigra and 0.93 (0.83-0.97) for the red nucleus. The points with susceptibility difference (95.2%, 20/21) located in the 95% CI of limits of agreement for the putamen and the thalamus measured on two different MR scanners. CONCLUSIONS: The intra-scanner reproducibility of QSM of the subcortical gray nuclei is superior to the inter-scanner reproducibility in healthy adults.


Assuntos
Substância Cinzenta , Imageamento por Ressonância Magnética , Adulto , Encéfalo/diagnóstico por imagem , Humanos , Ferro , Reprodutibilidade dos Testes , Substância Negra/diagnóstico por imagem
10.
Curr Med Imaging ; 16(8): 991-996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33081660

RESUMO

BACKGROUND: Quantitative susceptibility mapping (QSM) technique had been used to measure the magnetic susceptibility of brain tissue in clinical practice. However, QSM presented echo-time (TE) dependence, and an appropriate number of echo-times (nTEs) for QSM became more important to obtain the reliable susceptibility value. OBJECTIVE: The aim of the study was to explore the optimal nTEs for quantitative susceptibility mapping (QSM) measurements of basal ganglia nuclei in the healthy brain. METHODS: 3D multi-echo enhanced gradient recalled echo T2 star weighted angiography (ESWAN) sequence was acquired on a 3.0T MR scanner for QSM analysis. Regions of interests (ROIs) were drawn along the margin of the head of the caudate nucleus (HCN), putamen (Pu) and globus pallidus (GP). The mean susceptibility value and standard deviation of the ROIs were derived from the pixels within each region. RESULTS: CV analysis demonstrated that TE6, TE8 and TE14 ESWAN sequences presented consistent lower CV value (< 1) for QSM measure of HCN, Pu and GP. ANOVA identified that susceptibility value showed no significant difference between TE6 and TE8 in HCN, Pu and GP (P > 0.05). ICC analysis demonstrated that the susceptibility value of TE6-TE8 had the highest ICC value as compared with TE6-TE14 and TE8-TE14 in HCN, Pu and GP. Combined with the timeefficiency of MRI scanning, TE6 sequence could not only provide the reliable QSM measurement but also short imaging time. CONCLUSION: The current study identified that the optimal nTEs of ESWAN were 6 TEs (2.9ms ~ 80.9ms) for QSM measurement of basal ganglia nuclei in the healthy brain.


Assuntos
Mapeamento Encefálico , Encéfalo , Gânglios da Base/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Putamen/diagnóstico por imagem
11.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 275-278, 2020 Apr 28.
Artigo em Chinês | MEDLINE | ID: mdl-32385038

RESUMO

Fibrous meningioma is a common subtype of meningioma. Contrast-enhanced scan typically shows evident homogeneous enhancement,while ring enhancement has not been described. In this article,we report a case of fibrous meningioma with ring enhancement in cerebellopontine angle region.


Assuntos
Ângulo Cerebelopontino/diagnóstico por imagem , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Ângulo Cerebelopontino/patologia , Humanos , Imageamento por Ressonância Magnética
12.
Chin Med J (Engl) ; 133(5): 530-536, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32049744

RESUMO

BACKGROUND: Texture features were the intrinsic properties of the human tissues and could efficiently detect the subtle functional changes of involved tissue. The pathologic changes of the lateral pterygoid muscle (LPM) were significantly correlated with the temporomandibular disc displacement. However, the occult functional changes of LPM could not be detected by the naked eye on the medical images. The current study was aimed to evaluate the functional changes of the LPM in the patients with temporomandibular disorders (TMDs) using texture analysis. METHODS: Twenty-nine patients with TMD were performed with magnetic resonance (MR) imaging on a 3.0T MR scanner, who were consecutively recruited from the TMD clinic of Hainan Hospital of Chinese People's Liberation Army General Hospital from February 2019 to September 2019. The patients were classified into three groups according to the disc displacement: disc without displacement (DWoD), disc displacement with reduction (DDWR) and disc displacement without reduction (DDWoR). The gray-level co-occurrence matrix method was applied with the texture analysis of LPM on the axial T2-weighted imaging. The texture features included angular second moment, contrast, correlation, inverse different moment, and entropy. One-way analysis of variance was used for grouped comparisons and receiver operating characteristics (ROC) curve analysis was applied to evaluate the diagnostic efficacy of the texture parameters. RESULTS: Texture contrast of LPM presented significantly lower in DDWoR (46.30 [35.03, 94.48]) than that in DWoD (123.85 [105.06, 143.23]; test statistic = 23.05; P < 0.001). Texture entropy of LPM showed significant differences among DWoD (7.62 ±â€Š0.33), DDWR (6.76 ±â€Š0.35), and DDWoR (6.46 ±â€Š0.39) (PDWoD-DDWR < 0.001, PDWoD-DDWoR < 0.001, and PDDWR-DDWoR = 0.014). Area under the ROC curve (AUC) demonstrated that texture entropy had an excellent diagnostic accuracy for DWoD-DDWR (AUC = 0.96) and DWoD-DDWoR (AUC = 0.98). CONCLUSION: The texture contrast and entropy could identify the altered functional status of LPM in patients with TMD and could be considered as the effective imaging biomarker to evaluate the functional changes of LPM in TMD.


Assuntos
Imageamento por Ressonância Magnética/métodos , Músculos Pterigoides/patologia , Músculos Pterigoides/fisiopatologia , Transtornos da Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Adulto , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Pterigoides/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Adulto Jovem
13.
J Int Med Res ; 48(3): 300060519891332, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31849253

RESUMO

OBJECTIVES: To investigate the application value of the calcium-suppressed (CaSupp) images of dual-layer detector computed tomography (DLCT) in the evaluation of the temporomandibular joint (TMJ) discs. METHODS: Thirty-three healthy subjects underwent DLCT and magnetic resonance imaging (MRI) examinations. CaSupp images were reconstructed from the spectral-based images using a calcium suppression algorithm. The location, morphology, and thickness of the posterior band of the TMJ discs were evaluated on the oblique sagittal proton-density weighted images and CaSupp images. RESULTS: Of the 66 TMJ discs, anterior displacement was observed on 9 TMJ discs on MR images and 6 TMJ discs on CaSupp images, and posterior displacement was present on 3 TMJ discs on MR and CaSupp images. No significant difference was observed in TMJ disc displacement between MR images and CaSupp images (P value = 0.730). The TMJ discs without displacement had no significant difference in the thickness of the posterior band between the MR and CaSupp images (P value = 0.401). CONCLUSIONS: The calcium-suppressed technique in DLCT may be a simple and preliminary way to evaluate the TMJ disc displacement and structure.


Assuntos
Luxações Articulares , Transtornos da Articulação Temporomandibular , Cálcio , Humanos , Imageamento por Ressonância Magnética , Disco da Articulação Temporomandibular/diagnóstico por imagem , Tomografia Computadorizada por Raios X
14.
Chin Med Sci J ; 34(1): 33-37, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30961778

RESUMO

Objective To investigate the difference in texture features on diffusion weighted imaging (DWI) images between breast benign and malignant tumors.Methods Patients including 56 with mass-like breast cancer, 16 with breast fibroadenoma, and 4 with intraductal papilloma of breast treated in the Hainan Hospital of Chinese PLA General Hospital were retrospectively enrolled in this study, and allocated to the benign group (20 patients) and the malignant group (56 patients) according to the post-surgically pathological results. Texture analysis was performed on axial DWI images, and five characteristic parameters including Angular Second Moment (ASM), Contrast, Correlation, Inverse Difference Moment (IDM), and Entropy were calculated. Independent sample t-test and Mann-Whitney U test were performed for intergroup comparison. Regression model was established by using Binary Logistic regression analysis, and receiver operating characteristic curve (ROC) analysis was carried out to evaluate the diagnostic efficiency.Results The texture features ASM, Contrast, Correlation and Entropy showed significant differences between the benign and malignant breast tumor groups (PASM=0.014, Pcontrast=0.019, Pcorrelation=0.010, Pentropy=0.007). The area under the ROC curve was 0.685, 0.681, 0.754, and 0.683 respectively for the positive texture variables mentioned above, and that for the combined variables (ASM, Contrast, and Entropy) was 0.802 in the model of Logistic regression. Binary Logistic regression analysis demonstrated that ASM, Contrast and Entropy were considered as the specific imaging variables for the differential diagnosis of breast benign and malignant tumors.Conclusions The texture analysis of DWI may be a simple and effective tool in the differential diagnosis between breast benign and malignant tumors.


Assuntos
Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Fibroadenoma/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(6): 866-870, 2019 Dec 30.
Artigo em Chinês | MEDLINE | ID: mdl-31907141

RESUMO

The magnetic resonance imaging findings of multicystic encephalomalacia are featured by bilateral frontal large cystic lesion with corpus callosum involvement,evident heterogeneous enhancement of the lesion margin,ring hyperintensity on diffusion weighted imaging,and high choline peak and low N-acetylaspartate peak of the enhanced lesion margin on magnetic resonance spectroscopy.This article reports a case of multicystic encephalomalacia.


Assuntos
Encefalomalacia , Corpo Caloso , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
16.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(4): 573-576, 2018 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-30193615

RESUMO

The diagnostic criteria of splenic hemangioma is the delayed filling enhancement pattern on the dynamic contrast CT imaging or magnetic resonance (MR) T1-weighted image,which requires long examination time and thus decreases the MR scanning efficiency. Contrast-enhanced T2 fluid-attenuated inversion recovery (FLAIR) imaging is a new MR imaging technique that can be used to evaluate the intrinsic characteristics of hemangioma. However,few literature has discribed its role in diagnosing splenic hemangioma. In this article we reported one case of splenic hemangioma diagnosed by contrast-enhanced T2 FLAIR imaging,which reduced the MR scanning time and provided valuable experience for the diagnosis of splenic hemangioma.


Assuntos
Meios de Contraste , Hemangioma/diagnóstico por imagem , Aumento da Imagem , Imageamento por Ressonância Magnética , Humanos , Baço/diagnóstico por imagem , Baço/patologia
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(3): 436-438, 2018 Jun 28.
Artigo em Chinês | MEDLINE | ID: mdl-29978807

RESUMO

We reported a case with epidermoid cyst (EC) in the fourth ventricle. The insinuation and scalloping growth pattern were the distinctive imaging characteristics of EC in the fourth ventricle on magnetic resonance imaging. The accurate identification of the punctate enhancement of vessels around the lesion may be helpful for its differential diagnosis from hemangioblastoma.


Assuntos
Cisto Epidérmico/diagnóstico por imagem , Quarto Ventrículo/patologia , Diagnóstico Diferencial , Quarto Ventrículo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 39(2): 169-176, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28483013

RESUMO

Objective To investigate the difference of texture on conventional T2-weighted image (T2WI) between hepatic cyst and hepatic hemangioma. Methods All the subjects included 156 patients with hepatic cyst [A group:100 cases with equi or low signal on diffusion weighted imaging (DWI);B group:56 cases with high signal on DWI] and 100 patients with hemangioma (C group). Conventional magnetic resonance imaging T2WI,DWI and dynamic contrast enhancement were performed on all the patients,and the texture analysis was applied with the images of T2WI,and the texture parameters included angular second moment,contrast,correlation,inverse difference moment,and entropy. Independent sample t-test and Aspin-Welch test were performed for the comparisons among groups. Results All the texture parameters showed significant difference among groups [(A+B) group vs. C group:ρ angular second moment=0.000,ρcontrast=0.000,ρcorrelation=0.000,Pinverse difference moment=0.822,ρentropy=0.000;A group vs. C group:ρangular second moment=0.000,ρcontrast=0.000,ρcorrelation=0.000,ρinverse difference moment=0.092,ρentropy=0.000;B group vs. C group:ρangular second moment=0.000,ρcontrast=0.000,ρcorrelation=0.000,ρinverse difference moment=0.046,ρentropy=0.009],and receiver operating characteristic curve analysis demonstrated that contrast and correlation had high differential diagnostic values between hepatic cyst and hemangioma. Conclusion Hepatic cyst and hemangioma present evident different texture characteristics,and the texture analysis may be considered as a simple and effective tool in the differential diagnosis between hepatic cyst and hemangioma based on the images of T2WI.


Assuntos
Cistos/diagnóstico por imagem , Hemangioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Humanos , Fígado/patologia
19.
Stroke ; 46(8): 2081-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26138123

RESUMO

BACKGROUND AND PURPOSE: The relationship between chronic kidney disease and cerebral small vessel disease (cSVD), especially enlarged perivascular spaces (EPVS), has not been fully understood. This study aimed to investigate the association of chronic kidney disease and EPVS, as well as the total burden of cSVD on magnetic resonance imaging, expressed by the simultaneous presence of multiple markers of cSVD, among patients with first-ever lacunar stroke. METHODS: Four hundred and thirteen consecutive patients were prospectively enrolled. Centrum semiovale and basal ganglia EPVS on T2-weighted magnetic resonance imaging, as well as other imaging markers of cSVD, including lacune, white matter lesions, and cerebral microbleeds, were rated using validated scales. Chronic kidney disease was defined as either reduced estimated glomerular filtration rate or the presence of proteinuria. RESULTS: After adjustments for potential confounders by logistic regression, proteinuria and impaired estimated glomerular filtration rate were correlated with the severity of EPVS in both centrum semiovale (odds ratio [OR] 2.59; 95% confidence interval [CI] 1.19-5.64 and OR 2.37; 95% CI 1.19-4.73) and basal ganglia (OR 5.12; 95% CI 2.70-12.10 and OR 4.17; 95% CI 2.08-8.37). A similar association was also found between proteinuria and low estimated glomerular filtration rate levels and the comprehensive cSVD burden (OR 2.13; 95% CI 1.10-4.14 and OR 5.59; 95% CI 2.58-12.08). CONCLUSIONS: Proteinuria and impaired estimated glomerular filtration rate are associated with increasing EPVS severity and, furthermore, accumulated magnetic resonance imaging burden of cSVD in patients with first-ever acute lacunar stroke.


Assuntos
Gânglios da Base/patologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico , Imageamento por Ressonância Magnética , Insuficiência Renal Crônica/diagnóstico , Acidente Vascular Cerebral Lacunar/diagnóstico , Idoso , Gânglios da Base/metabolismo , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Doenças de Pequenos Vasos Cerebrais/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/metabolismo , Acidente Vascular Cerebral Lacunar/epidemiologia , Acidente Vascular Cerebral Lacunar/metabolismo
20.
Atherosclerosis ; 241(2): 371-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26071660

RESUMO

Genome-wide association studies (GWASs) have identified several risk loci for coronary artery calcification. Four single-nucleotide polymorphisms (SNPs, rs1537370, rs1333049, rs2026458 and rs9349379) were associated with coronary artery calcification with P values less than 5 × 10(-8) in GWASs. It is unclear if these associations exist in other vascular beds. Thus, we evaluated the impacts of these four SNPs on carotid artery and aortic arch calcification in this study. Computed tomography was applied to quantify the calcification of carotid artery and aortic arch. 860 patients with stroke completed calcification quantification and genotype testing were included in data analysis. Each SNP was evaluated for the association with carotid artery calcification, and with aortic arch calcification using generalized linear model. Among the four tested SNPs, rs2026458 was associated with calcification in both carotid artery (ß = 0.31, 95% confidence interval [CI] 0.10-0.52, P = 0.003) and aortic arch (ß = 0.32, 95% CI 0.10-0.54, P = 0.004), while rs1333049 was only associated with carotid artery calcification (ß = 0.28, 95% CI 0.06-0.50, P = 0.011). In gender-stratified analyses, rs2026458 had significant impacts on carotid artery (P = 0.003) and aortic arch calcification (P = 0.008) in male, but not in female patients; while rs1537370 was significantly associated with carotid artery calcification in female (P = 0.013), but not in male patients. In conclusion, SNPs associated with coronary artery calcification may also increase the risk of calcification in other arteries such as carotid artery and aortic arch.


Assuntos
Aorta Torácica , Doenças da Aorta/genética , Aterosclerose/genética , Doenças das Artérias Carótidas/genética , Polimorfismo de Nucleotídeo Único , Calcificação Vascular/genética , Idoso , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico , Doenças da Aorta/etnologia , Aortografia/métodos , Povo Asiático/genética , Aterosclerose/diagnóstico , Aterosclerose/etnologia , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/etnologia , Distribuição de Qui-Quadrado , China , Feminino , Estudos de Associação Genética , Marcadores Genéticos , Testes Genéticos , Disparidades nos Níveis de Saúde , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Fenótipo , Fatores de Risco , Fatores Sexuais , Calcificação Vascular/diagnóstico , Calcificação Vascular/etnologia
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