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Detecting altered spontaneous activities of different brain areas in diabetic vitreous hemorrhage patients:a magnetic resonance imaging study
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作者 Kai Yan Jing Yu +9 位作者 Yan-Mei Zeng Cheng Chen Lei Zhong Jin-Yu Hu Liang-Qi He Xiao-Yu Wang Qian Ling Xu Chen Yi Shao Yao Yu 《International Journal of Ophthalmology(English edition)》 2026年第2期273-280,共8页
AIM:To compare spontaneous brain regional activities between diabetic vitreous hemorrhage patients(DVHs)and healthy controls(HCs).METHODS:Thirty-two DVHs and 32 HCs were enrolled in this study.Baseline demographic and... AIM:To compare spontaneous brain regional activities between diabetic vitreous hemorrhage patients(DVHs)and healthy controls(HCs).METHODS:Thirty-two DVHs and 32 HCs were enrolled in this study.Baseline demographic and vision data were compared between groups using an independent sample t-test.Resting-state functional magnetic resonance imaging(rs-fMRI)was used in all participants.fMRI data was obtained and analyzed using MRIcro and SPM8 software.Fractional amplitude of low-frequency fluctuation(fALFF)technology was used to measure regional spontaneous brain activity,and sensitivity was tested using receiver operating characteristic curves(ROCs).The fALFF values were analyzed using REST software and two-sample t-tests were used to compare values between groups.Hospital anxiety and depression scale(HADS)score was assessed in DVHs and Pearson’s correlation was used to test relationships between mean fALFF value and both HADS score and duration of DVH.RESULTS:Except for the best-corrected visual acuity(BCVA)in both eyes,which showed a statistically significant difference(P<0.05),there were no statistically significant differences in the other indicators(P>0.05)between the HCs and DVHs group.Compared with controls,fALFF value was higher in DVH in cerebellum posterior lobe(CPL)and lower in right anterior cingulate cortex(ACC)and right medial orbitofrontal cortex(OFC).In DVH patients,mean fALFF value of CPL was positively correlated with HADS score and duration of diabetes.However,no such correlation was found,for right ACC or right medial OFC.DVH may lead to abnormal activities in certain brain regions related to visual control and mood.CONCLUSION:Visual impairment caused by DVH may lead to adjustment in regional visual brain activities and may be related to depression or reward system processing in some brain regions. 展开更多
关键词 diabetic vitreous hemorrhage functional magnetic resonance fractional amplitude of low-frequency fluctuation cerebellum posterior lobe right anterior cingulate cortex right medial orbitofrontal cortex clinical trials
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A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study
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作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
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A novel harmonic resonance prevention measure for railway power conditioner-network-train interaction system
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作者 Shaofeng Xie Fan Zhong 《Railway Engineering Science》 2025年第2期290-310,共21页
The integration of a large number of power electronic converters,such as railway power conditioner(RPC),introduces a series of problems,including harmonic interaction,stability issues,and wideband resonance,into the r... The integration of a large number of power electronic converters,such as railway power conditioner(RPC),introduces a series of problems,including harmonic interaction,stability issues,and wideband resonance,into the railway power supply system.To address these challenges,this paper proposes a novel harmonic resonance prevention measure for RPC-network-train interaction system.Firstly,a harmonic model,a parallel resonance impedance model,a series resonance admittance model,and a control stability model are each established for the RPC-network-train interaction system.Secondly,a comprehensive resonance impact factor(CRIF)is proposed to efficiently and accurately identify the key components affecting resonance,and to provide the selection results of optimization parameters for resonance prevention.Next,the initially selected parameters are constrained by the requirements of ripple current,reactive power and stability.Subsequently,the impedance parameters(control parameters and filter parameters)of the RPC are optimized with the objective of reshaping the parallel resonance impedance and series resonance admittance of the RPC-network-train interaction system,ensuring the output current har-monics of RPC meet standards to achieve resonance prevention,while ensuring the stable operation of the RPC.Finally,the proposed resonance prevention measure is verified under both light load and heavy load conditions using a simulation platform and a hardware-in-the-loop experimental platform. 展开更多
关键词 Electrical railway Railway power conditioner(RPC) Harmonic interaction Series resonance Parallel resonance Harmonic resonance prevention
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High sensitivity and low refractive index D-type photonic crystal fiber sensor based on surface plasmon resonance
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作者 GAO Jiachen MING Xianbing WEN Xiang 《Optoelectronics Letters》 2025年第9期528-534,共7页
A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electro... A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection. 展开更多
关键词 high sensitivity d type photonic crystal fiber surface plasmon resonance spr gold film maximum resolution refractive index low refractive index surface plasmon resonance
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Ventricular arrhythmia in an elderly patient with renal cell carcinoma:seeing the invisible with cardiac magnetic resonance
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作者 Shing Ching Kei Tung Wong 《Journal of Geriatric Cardiology》 2025年第8期757-758,共2页
Renal cell carcinoma(RCC)is an aggressive tumor known for its propensity to invade the inferior vena cava(IVC)into the heart.Cardiac metastasis of RCC without IVC involvement is rare.Even rarer is ventricular arrhythm... Renal cell carcinoma(RCC)is an aggressive tumor known for its propensity to invade the inferior vena cava(IVC)into the heart.Cardiac metastasis of RCC without IVC involvement is rare.Even rarer is ventricular arrhythmia as the primary manifestation of cardiac metastasis of RCC with only two cases reported.[1,2]We add to the literature the third case,the diagnosis of which was only possible with cardiac magnetic resonance(CMR). 展开更多
关键词 ventricular arrhythmia renal cell carcinoma cardiac magnetic resonance cmr renal cell carcinoma rcc cardiac metastasis cardiac magnetic resonance elderly patient
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Evaluating luminal and post-operative Crohn’s disease activity on magnetic resonance enterography: A review of radiological disease activity scores
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作者 Richard W Lo Gauraang Bhatnagar +1 位作者 Numan Kutaiba Ashish R Srinivasan 《World Journal of Gastroenterology》 2025年第26期22-46,共25页
Magnetic resonance enterography(MRE)is a non-invasive,radiation-free imaging modality that facilitates the assessment of transmural Crohn’s disease activity.It offers advantages over ileo-colonoscopy,which is limited... Magnetic resonance enterography(MRE)is a non-invasive,radiation-free imaging modality that facilitates the assessment of transmural Crohn’s disease activity.It offers advantages over ileo-colonoscopy,which is limited to mucosal-level evaluation,cannot routinely assess small bowel segments proximal to the terminal ileum,and is unable to detect extra-luminal complications.Despite these ad-vantages,the lack of standardised criteria for defining and appraising radiologic disease activity on MRE has contributed to variability in interpretation and clinical application.In response,multiple MRE-based scoring systems have been developed to quantify radiological Crohn’s disease activity in both luminal and post-operative settings.Radiological disease activity scores specific to luminal Crohn’s disease include the magnetic resonance index of activity(MaRIA),simplified MaRIA,Nancy score,London score,Crohn’s disease magnetic reso-nance imaging(MRI)index,Clermont score,paediatric inflammatory Crohn’s MRE index,MRE global score,MRE index,and modified Clermont score.The MR score and the MRI in Crohn’s disease to predict postoperative recurrence index have been specifically developed to evaluate post-operative disease recurrence in Crohn’s disease.Nevertheless,heterogeneity in scoring parameters,variability in computational complexity,and a lack of consensus regarding optimal score selection,have impeded widespread clinical adoption of radiological disease activity scores.This narrative review aims to summarise the key imaging features of luminal Crohn’s disease,explore their integration into existing MRE scoring indices,and critically compare the structure,strengths,and clinical applicability of each.Furthermore,MRI scores specific to post-operative Crohn’s disease evaluation,and the assessment of cumulative bowel wall damage using the Lemann index will also be discussed. 展开更多
关键词 Crohn’s disease Imaging Radiological disease activity Magnetic resonance imaging Magnetic resonance enterography Transumural healing
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MMP-9-responsive probe for fiuorescence-magnetic resonance dual-mode imaging of hepatocellular carcinoma models with different metastatic capacities
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作者 Qiuye Wang Yabing Sun +8 位作者 Liangxue Lai Haijing Cui Yonglong Ye Ming Yang Weihao Zhu Bo Yuan Quanliang Mao Wenzhi Ren Aiguo Wu 《Chinese Chemical Letters》 2025年第4期351-356,共6页
Visual assessment of tumor metastatic capacity is crucial for predicting hepatocellular carcinoma(HCC)prognosis and guiding clinical therapeutic approaches.In this study,we developed an enzyme-responsive probe based o... Visual assessment of tumor metastatic capacity is crucial for predicting hepatocellular carcinoma(HCC)prognosis and guiding clinical therapeutic approaches.In this study,we developed an enzyme-responsive probe based on the peptide GK10,which is selectively cleaved by matrix metalloproteinase-9(MMP-9),a critical marker for metastasis in HCC.The GK10 peptide was conjugated with near-infrared fiuorescent molecule IR783,fiuorescent quencher black hole quencher 3(BHQ3),and magnetic resonance(MR)contrast agent DOTA-Gd,forming the IR783-GK10-BHQ3-Gd probe.Upon MMP-9 cleavage of GK10,BHQ3 is released from the probe,thereby amplifying the previously quenched IR783 fiuorescence signal.In vitro experiments demonstrate the probe's impressive detection limit for MMP-9,as low as 1.84 ng/m L.Moreover,in vivo imaging results reveal that the probe can differentiate liver cancers with varying metastatic capacities.The fiuorescence and MR imaging signal intensity of high metastatic HCC are approximately1.2 times greater than that of low metastatic HCC.Thus,this engineered probe holds promise as a valuable tool for evaluating HCC metastatic capacity through fiuorescence-MR dual-mode imaging. 展开更多
关键词 Hepatocellular carcinoma Matrix metalloproteinase-9 Fluorescence imaging Magneticresonance imaging F?rster resonance energy transfer
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In vivo magnetic resonance spectroscopy of liver tumors and metastases 被引量:8
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作者 EGW ter Voert L Heijmen +1 位作者 HWM van Laarhoven A Heerschap 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第47期5133-5149,共17页
Primary liver cancer is the fifth most common malignancy in men and the eighth in women worldwide. The liver is also the second most common site for metastatic spread of cancer. To assist in the diagnosis of these liv... Primary liver cancer is the fifth most common malignancy in men and the eighth in women worldwide. The liver is also the second most common site for metastatic spread of cancer. To assist in the diagnosis of these liver lesions non-invasive advanced imaging techniques are desirable. Magnetic resonance (MR) is commonly used to identify anatomical lesions, but it is a very versatile technique and also can provide specific information on tumor pathophysiology and metabolism, in particular with the application of MR spectroscopy (MRS). This may include data on the type, grade and stage of tumors, and thus assist in further management of the disease. The purpose of this review is to summarize and discuss the available literature on proton, phosphorus and carbon-13-MRS as performed on primary liver tumors and metastases, with human applications as the main perspective. Upcoming MRSapproaches with potential applications to liver tumors are also included. Since knowledge of some technical background is indispensable to understand the results, a basic introduction of MRS and some technical issues of MRS as applied to tumors and metastases in the liver are described as well. In vivo MR spectroscopy of tumors in a metabolically active organ such as the liver has been demonstrated to provide important information on tumor metabolism, but it also is challenging as compared to applications on some other tissues, in particular in humans, mostly because of its abdominal location where movement may be a disturbing factor. 展开更多
关键词 METASTASIS METABOLISM Proton magneticresonance spectroscopy Phosphorus magnetic reso-nance spectroscopy Carbon-13 magnetic resonancespectroscopy Magnetic resonance spectroscopy Mag-netic resonance
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Multiparametric magnetic resonance imaging-based predictive model for chemotherapy response in colorectal cancer patients with gene mutations 被引量:2
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作者 Wen-Yan Kang Wen-Ming Deng +4 位作者 Xiao-Qin Ye Yi-Hong Zhong Xiao-Jun Li Ling-Ling Feng De-Hong Luo 《World Journal of Gastrointestinal Oncology》 2025年第10期280-289,共10页
BACKGROUND Patients harboring gene mutations like KRAS,NRAS,and BRAF demonstrate highly variable responses to chemotherapy,posing challenges for treatment optimization.Multiparametric magnetic resonance imaging(MRI),w... BACKGROUND Patients harboring gene mutations like KRAS,NRAS,and BRAF demonstrate highly variable responses to chemotherapy,posing challenges for treatment optimization.Multiparametric magnetic resonance imaging(MRI),with its noninvasive capability to assess tumor characteristics in detail,has shown promise in evaluating treatment response and predicting therapeutic outcomes.This technology holds potential for guiding personalized treatment strategies tailored to individual patient profiles,enhancing the precision and effectiveness of colorectal cancer care.AIM To create a multiparametric MRI-based predictive model for assessing chemotherapy efficacy in colorectal cancer patients with gene mutations.METHODS This retrospective study was conducted in a tertiary hospital,analyzing 157 colorectal cancer patients with gene mutations treated between August 2022 and December 2023.Based on chemotherapy outcomes,the patients were categorized into favorable(n=60)and unfavorable(n=50)response groups.Univariate and multivariate logistic regression analyses were performed to identify independent predictors of chemotherapy efficacy.A predictive nomogram was constructed using significant variables,and its performance was assessed using the area under the receiver operating characteristic curve(AUC)in both training and validation sets.RESULTS Univariate analysis identified that tumor differentiation,T2 signal intensity ratio,tumor-to-anal margin distance,and MRI-detected lymph node metastasis as significantly associated with chemotherapy response(P<0.05).Multivariate Logistics regression confirmed these four parameters as independent predictors.The predictive model demonstrated strong discrimination,with an AUC of 0.938(sensitivity:86%;specificity:92%)in the training set,and 0.942(sensitivity:100%;specificity:83%)in the validation set.CONCLUSION We established and validated a multiparametric MRI-based model for predicting chemotherapy response in colorectal cancer patients with gene mutations.This model holds promise for guiding individualized treatment strategies. 展开更多
关键词 Colorectal cancer RAS gene mutation Multiparametric magnetic resonance imaging CHEMOTHERAPY Predictive model
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Congenital Intracranial Tumors:Prenatal Diagnosis by Fetal Magnetic Resonance Imaging 被引量:1
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作者 Jing-Ya Ren Hui Ji +1 位作者 Ming Zhu Su-Zhen Dong 《iRADIOLOGY》 2025年第3期203-208,共6页
Fetal intracranial tumors are rare,accounting for approximately 0.5%–1.9%of all pediatric tumors,though the true incidence may be underestimated.These tumors often present with distinct histopathological features,ima... Fetal intracranial tumors are rare,accounting for approximately 0.5%–1.9%of all pediatric tumors,though the true incidence may be underestimated.These tumors often present with distinct histopathological features,imaging characteristics,and clinical behavior compared to their postnatal counterparts.This review summarizes the current understanding of the prenatal diagnosis and characterization of fetal brain tumors,with a particular focus on the role of fetal magnetic resonance imaging(MRI).We discuss the advantages of advanced MR sequences in enhancing lesion detection and anatomical delineation following suspicious findings on obstetric ultrasound.Common tumor types encountered in utero—including teratomas,as-trocytomas,medulloblastomas,choroid plexus papillomas,and craniopharyngiomas—are reviewed in terms of imaging fea-tures,differential diagnosis,and clinical implications.Furthermore,the review addresses the diagnostic challenges,prognostic considerations,and the potential role of fetal MRI in guiding perinatal management and parental counseling. 展开更多
关键词 BRAIN CONGENITAL FETUS magnetic resonance imaging TUMOR
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Value of Magnetic Resonance Spectroscopy for Examining Fetal Brain Development in Mid-to Late Pregnancy 被引量:1
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作者 Dejuan Shan Yi Zhang +3 位作者 Maobo Wang Yanyan Liu Yudong Wang Lianxiang Xiao 《iRADIOLOGY》 2025年第3期209-213,共5页
Background:Magnetic resonance spectroscopy(MRS)represents a significant advancement in the noninvasive assessment of brain metabolism.MRS can provide valuable metabolic information and facilitate more accurate diagnos... Background:Magnetic resonance spectroscopy(MRS)represents a significant advancement in the noninvasive assessment of brain metabolism.MRS can provide valuable metabolic information and facilitate more accurate diagnoses of intrauterine fetal brain development than was previously possible.To obtain information regarding normal intrauterine fetal brain metabolism and to establish gestational age-specific reference values for normal fetal brain metabolites for subsequent use in MRS,we conducted MRS scans of normal fetal brains during mid-to late-term pregnancies,along with related processing.Methods:In this prospective study,MRS scans were conducted on 109 fetuses,with a total of 54 normal fetal brains enrolled on the basis of specific inclusion and exclusion criteria.We analyzed metabolic ratios,including the sum of N-acetylaspartate(NAA)and total N-acetylaspartate(tNAA),total choline(tCho),inositol(Ins),and total creatine(tCr),in relation to gestational age.Results:Gestational age was significantly correlated with specific metabolic ratios(Ins/tCr:r=-0.75,p<0.0001;tCho/tCr:r=-0.50,p<0.0001),especially tNAA/tCho(tNAA/tCho:r=0.54,p<0.0001)and tNAA/Ins(r=0.56,p<0.0001),providing a baseline for fetal brain metabolic assessment.Linear regression analysis was used to calculate regression lines for fetal brain metabolite ratios.Slopes were tested at p of 0.05.Conclusions:The current findings confirmed a significant correlation between fetal brain metabolites and gestational age,supporting the feasibility of establishing standard values for these metabolites in fetal brain assessment. 展开更多
关键词 CHOLINE CREATINE fetal brain metabolism magnetic resonance spectroscopy N-ACETYLASPARTATE
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Predictive value of magnetic resonance imaging parameters combined with tumor markers for rectal cancer recurrence risk after surgery 被引量:1
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作者 Lei Wu Jing-Jie Zhu +2 位作者 Xiao-Han Liang He Tong Yan Song 《World Journal of Gastrointestinal Surgery》 2025年第2期161-172,共12页
BACKGROUND An increasing number of studies to date have found preoperative magnetic resonance imaging(MRI)features valuable in predicting the prognosis of rectal cancer(RC).However,research is still lacking on the cor... BACKGROUND An increasing number of studies to date have found preoperative magnetic resonance imaging(MRI)features valuable in predicting the prognosis of rectal cancer(RC).However,research is still lacking on the correlation between preoperative MRI features and the risk of recurrence after radical resection of RC,urgently necessitating further in-depth exploration.AIM To investigate the correlation between preoperative MRI parameters and the risk of recurrence after radical resection of RC to provide an effective tool for predicting postoperative recurrence.METHODS The data of 90 patients who were diagnosed with RC by surgical pathology and underwent radical surgical resection at the Second Affiliated Hospital of Bengbu Medical University between May 2020 and December 2023 were collected through retrospective analysis.General demographic data,MRI data,and tumor markers levels were collected.According to the reviewed data of patients six months after surgery,the clinicians comprehensively assessed the recurrence risk and divided the patients into high recurrence risk(37 cases)and low recurrence risk(53 cases)groups.Independent sample t-test andχ2 test were used to analyze differences between the two groups.A logistic regression model was used to explore the risk factors of the high recurrence risk group,and a clinical prediction model was constructed.The clinical prediction model is presented in the form of a nomogram.The receiver operating characteristic curve,Hosmer-Lemeshow goodness of fit test,calibration curve,and decision curve analysis were used to evaluate the efficacy of the clinical prediction model.RESULTS The detection of positive extramural vascular invasion through preoperative MRI[odds ratio(OR)=4.29,P=0.045],along with elevated carcinoembryonic antigen(OR=1.08,P=0.041),carbohydrate antigen 125(OR=1.19,P=0.034),and carbohydrate antigen 199(OR=1.27,P<0.001)levels,are independent risk factors for increased postoperative recurrence risk in patients with RC.Furthermore,there was a correlation between magnetic resonance based T staging,magnetic resonance based N staging,and circumferential resection margin results determined by MRI and the postoperative recurrence risk.Additionally,when extramural vascular invasion was integrated with tumor markers,the resulting clinical prediction model more effectively identified patients at high risk for postoperative recurrence,thereby providing robust support for clinical decision-making.CONCLUSION The results of this study indicate that preoperative MRI detection is of great importance for predicting the risk of postoperative recurrence in patients with RC.Monitoring these markers helps clinicians identify patients at high risk,allowing for more aggressive treatment and monitoring strategies to improve patient outcomes. 展开更多
关键词 Rectal cancer Magnetic resonance imaging RECURRENCE Prediction model Tumor markers
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Renal angiomyolipomas:Typical and atypical features on computed tomography and magnetic resonance imaging 被引量:1
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作者 Andres Labra Giancarlo Schiappacasse +1 位作者 Diego Constenla Joaquin Cristi 《World Journal of Radiology》 2025年第2期11-20,共10页
Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is... Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is to discuss computed tomography(CT)and magnetic resonance imaging findings for both typical and atypical renal AMLs,along with their associated complications.AMLs are typically defined as solid triphasic tumors composed of varying amounts of dysmorphic and tortuous blood vessels,smooth muscle components and adipose tissue.In an adult,a classical renal AML appears as a solid,heterogeneous renal cortical mass with macroscopic fat.However,up to 5%of AMLs contain minimal fat and cannot be reliably diagnosed by imaging.Fat-poor AMLs can appear as hyperattenuating masses on unenhanced CT and as hypointense masses on T2WI;other AMLs may be isodense or exhibit cystic components.Hemorrhage is the most common complication,and AMLs with hemorrhage can mimic other tumors,making their diagnosis challenging.Understanding the variable and heterogeneous nature of this neoplasm to correctly classify renal AMLs and to avoid misdiagnosis of other renal lesions is crucial. 展开更多
关键词 Kidney neoplasms ANGIOMYOLIPOMA Classic angiomyolipoma-fat poor angiomyolipoma Tomography X-ray computed Magnetic resonance imaging
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High-resolution direct magnetic resonance imaging fistulography with hydrogen peroxide for diagnosing anorectal fistula: A preliminary retrospective study 被引量:1
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作者 Can-Can Chang Long-Hu Qiao +5 位作者 Zhen-Qi Zhang Xiao Tian Yu Zhang Wen-Wen Cheng Xia Wang Qing Yang 《World Journal of Radiology》 2025年第1期32-40,共9页
BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)i... BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes. 展开更多
关键词 Key fistula-in-ano Magnetic resonance imaging Hydrogen peroxide Perianal abscess Fistulography
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Effects of plasma screening on the^(1)P^(o)(n=3,n=4)resonance states of H-and He using the stabilization method
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作者 仲子鑫 吕柄宽 +2 位作者 姜子实 KAR Sabyasachi HO Yew Kam 《黑龙江大学自然科学学报》 2025年第4期469-487,共19页
The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wav... The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wave functions.Two plasma mediums,namely,the Debye plasma and quantum plasma environments are considered.The screened Coulomb potential(SCP)obtained from Debye-Hückel model is used to represent Debye plasma environments and the exponential cosine screened Coulomb potential(ECSCP)obtained from a modified Debye-Hückel model is used to represent quantum plasma environments.The resonance parameters(resonance positions and widths)are presented in terms of the screening parameters. 展开更多
关键词 quantum plasma Debye plasma P-wave resonance states correlated exponential wave functions stabilization method
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Prenatal Ultrasound and Magnetic Resonance Imaging Features and Postnatal Outcomes of Congenital Hepatic Hemangioma:A Retrospective Analysis 被引量:1
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作者 Luyao Yang Jianbo Teng Xinhong Wei 《iRADIOLOGY》 2025年第3期214-221,共8页
Background:Congenital hepatic hemangioma(CHH)is a rare benign vascular tumor that occurs prenatally.However,only a few cases have been summarized and evaluated for the prenatal and postnatal imaging features of CHH,an... Background:Congenital hepatic hemangioma(CHH)is a rare benign vascular tumor that occurs prenatally.However,only a few cases have been summarized and evaluated for the prenatal and postnatal imaging features of CHH,and no studies have conducted long-term follow-up on it.This study aimed to explore the ultrasound and magnetic resonance features,growth patterns,and clinical outcomes of CHH.Methods:Thirty-six pregnancies with a prenatal fetal diagnosis and postnatal diagnosis of CHH were studied.CHHs were grouped into those with a diameter≥4 cm and those with a diameter<4 cm according to the largest diameter.Fisher's exact test was used to compare the imaging characteristics between the groups.The volume of CHHs was measured at each follow-up visit to plot the growth pattern of the tumors,and the volume of CHHs was compared before and after birth using a rank sum test analysis.Results:Thirty-three cases of CHHs were confirmed by postnatal imaging,and three were confirmed by a biopsy.Mixed echoes were more common in the diameter≥4 cm group than in the diameter<4 cm group(p=0.026).Complications were more likely to occur in the large-diameter group.Eighteen(54.5%)cases were classified as rapidly involuting congenital hemangioma,nine(27.3%)as partially involuting congenital hemangioma,and two(6.1%)as noninvoluting congenital hemangioma.A new type of CHH was identified in which four(12.1%)cases continued to proliferate after birth and spontaneously subsided in subsequent months.The CHH volume decreased with age and was significantly decreased at 9 months postnatal compared to birth(p=0.001).Conclusion:This study showed the imaging features of CHH were associated with the lesion size.Based on postnatal follow-up,a new type of CHH was identified.If there are no complications at birth in CHH cases,a good prognosis is indicated. 展开更多
关键词 congenital hepatic hemangioma magnetic resonance imaging prognosis ULTRASONOGRAPHY
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Magnetic resonance imaging bias field correction improves tumor prognostic evaluation after transcatheter arterial chemoembolization for liver cancer 被引量:1
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作者 Ke Liu Jun-Biao Li +1 位作者 Yong Wang Yan Li 《World Journal of Gastrointestinal Surgery》 2025年第4期207-220,共14页
BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evalu... BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evaluate accurately using conventional two-dimensional imaging criteria due to the tumor’s diffuse and multifocal growth pattern.Volumetric imaging,especially enhanced tumor volume(ETV),offers a more comprehensive assessment.Nonetheless,bias field inhomogeneity in magnetic resonance imaging(MRI)poses challenges,potentially skewing volumetric measurements and undermining prognostic evaluation.AIM To investigate whether MRI bias field correction enhances the accuracy of volumetric assessment of infiltrative hepatocellular carcinoma treated with TACE,and to analyze how this improved measurement impacts prognostic prediction.METHODS We retrospectively collected data from 105 patients with invasive liver cancer who underwent TACE treatment at the Affiliated Hospital of Xuzhou Medical University from January 2020 to January 2024.The improved N4 bias field correction algorithm was applied to process MRI images,and the ETV before and after treatment was calculated.The ETV measurements before and after correction were compared,and their relationship with patient prognosis was analyzed.A Cox proportional hazards model was used to evaluate prognostic factors,with Martingale residual analysis determining the optimal cutoff value,followed by survival analysis.RESULTS Bias field correction significantly affected ETV measurements,with the corrected baseline ETV mean(505.235 cm^(3))being significantly lower than before correction(825.632 cm^(3),P<0.001).Cox analysis showed that the hazard ratio(HR)for corrected baseline ETV(HR=1.165,95%CI:1.069-1.268)was higher than before correction(HR=1.063,95%CI:1.031-1.095).Using 412 cm^(3) as the cutoff,the group with baseline ETV<415 cm^(3) had a longer median survival time compared to the≥415 cm^(3) group(18.523 months vs 8.926 months,P<0.001).The group with an ETV reduction rate≥41%had better prognosis than the<41%group(17.862 months vs 9.235 months,P=0.006).Multivariate analysis confirmed that ETV reduction rate(HR=0.412,P<0.001),Child-Pugh classification(HR=0.298,P<0.001),and Barcelona Clinic Liver Cancer stage(HR=0.578,P=0.045)were independent prognostic factors.CONCLUSION Volume imaging based on MRI bias field correction can improve the accuracy of evaluating the efficacy of TACE treatment for invasive liver cancer.The corrected ETV and its reduction rate can serve as independent indicators for predicting patient prognosis,providing important reference for developing individualized treatment strategies. 展开更多
关键词 Invasive liver cancer Transcatheter arterial chemoembolization Magnetic resonance imaging Bias field correction Volume imaging
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Agricultural and environmental significance of soil organic matter and plant biomass:Insight from ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry 被引量:1
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作者 Zhongqi HE 《Pedosphere》 2025年第1期3-7,共5页
Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)is an advanced instrument capable of separating and determining molecular mass-to-charge ratios with sub-ppm level accuracy.A ... Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)is an advanced instrument capable of separating and determining molecular mass-to-charge ratios with sub-ppm level accuracy.A typical FT-ICR MS spectrogram can identify hundreds to thousands of formulas in a complex sample.This perspective briefly examines the application of FT-ICR MS to soil organic matter and plant biomass studies,highlighting their significant contributions to sustainable agriculture and environment. 展开更多
关键词 soil mass resonance
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Resonance analysis of^(159)Tb(n,γ)reaction based on the CSNS Back-n experiment 被引量:1
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作者 De-Xin Wang Su-Ya-La-Tu Zhang +14 位作者 Wei Jiang Jie Ren Mei-Rong Huang Jing-Yu Tang Xi-Chao Ruan Hong-Wei Wang Long-Xiang Liu Xue Li Dan-Dan Niu Guo Li Gu-Fu Meng Yong-Shun Huang Zhi-Long Wang Yu Bai Xue Yang 《Nuclear Science and Techniques》 2025年第3期85-94,共10页
The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were... The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were performed for the neutron capture cross sections of 159Tb measured at the China Spallation Neutron Source(CSNS)backscattering white neutron beamline(Back-n)facility.The resonance parameters were extracted from the R-Matrix code SAMMY and fitted to the experimental capture yield up to the 1.2 keV resolved resonance region(RRR).The average resonance parameters were determined by performing statistical analysis on the set of the resonance parameters in the RRR.These results were used to fit the measured average capture cross sections using the FITACS code in the unresolved resonance region from 2 keV to 1 MeV.The contributions of partial waves l=0,1,2 to the average capture cross sections are reported. 展开更多
关键词 Statistical analysis resonance parameters ^(159)Tb(n γ)cross section γ
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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging
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作者 Holly Flyger Samantha J.Holdsworth +2 位作者 Alistair J.Gunn Laura Bennet Hamid Abbasi 《Neural Regeneration Research》 SCIE CAS 2025年第11期3144-3150,共7页
Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental disability.Detailed asse... Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental disability.Detailed assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and electroencephalography.At present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic encephalopathy.This review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent articles.This review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic accuracy.Many challenges limit the timing consistency,particularly the need for intensive care and clinical monitoring.Conversely,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after birth.This suggests that in the future it will be important to explore a wider range of times after hypoxic-ischemic encephalopathy to fully understand the optimal timing for predicting long-term outcomes. 展开更多
关键词 magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia
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