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Predictors of prognosis in Alzheimer’s disease: The role of cognitive dysfunction, immune abnormalities, and advanced neuroimaging
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作者 Hafsa Arshad Raja Abdulqadir J Nashwan 《World Journal of Clinical Cases》 SCIE 2024年第27期6004-6006,共3页
Alzheimer’s disease(AD)is a grave illness that results in cognitive and social issues.A recent study examined the association between neuroimaging results,cognitive dysfunction,atypical cellular immune function,and p... Alzheimer’s disease(AD)is a grave illness that results in cognitive and social issues.A recent study examined the association between neuroimaging results,cognitive dysfunction,atypical cellular immune function,and poor prognostic factors in AD patients who demonstrated poor prognosis.Poor prognosis was associated with abnormal cellular immune function,extrapyramidal symptoms,altered consciousness,abnormal electroencephalogram,modified Rankin scale,increased neutrophil lymphocyte ratio,and severe pneumonia.The impaired cellular immune function characterized by a reduction in the blood T lym-phocytes’proportion predicted poor prognosis as an independent risk factor in AD.Early initiation and maintenance of AD medications is associated with better outcomes. 展开更多
关键词 Amyloid beta peptide Alzheimer's disease DEMENtIA Cellular immunity PROGNOSIS t lymphocytes magnetic resonance spectroscopy
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Transcraneal Magnetic Stimulation Improves Sleep Parameters in Patients Affected with Imsomnia Associated to Electroencephalographic Abnormalities 被引量:3
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作者 Oscar Sánchez-Escandón Yoaly Arana-Lechuga +6 位作者 Guadalupe Terán-Pérez ángel Ruiz-Chow Enrique Esqueda-Leon Rosa Obdulia González-Robles Paul Shkurovich-Bialik Miguel ángel Collado-Corona Javier Velázquez-Moctezuma 《Neuroscience & Medicine》 2014年第1期72-77,共6页
Insomnia is one of the most frequently observed sleep disorders, affecting nearly 10% of the general population. It has multiple etiological factors. Recently, it has been reported that EEG abnormalities are associate... Insomnia is one of the most frequently observed sleep disorders, affecting nearly 10% of the general population. It has multiple etiological factors. Recently, it has been reported that EEG abnormalities are associated with insomnia in patients previously diagnosed as idiopathic insomniacs. In addition, transcranial magnetic stimulation (TMS) has shown to be effective in the treatment of disorders characterized by neural hyper-excitability. Method: In the present study, patients with insomnia and EEG abnormalities were submitted to slow repetitive trans-cranial magnetic stimulation, for 15 minutes daily during 10 days. Polysomnographic recordings were performed before and after TMS. Results: The results indicate that the presence of EEG abnormalities significantly decreased after TMS. In addition, most of the sleep parameters showed significant improvement. Conclusions: These data support the notion that TMS is a reliable therapeutic tool for patients affected with abnormalities linked to neuronal hyper-excitability. 展开更多
关键词 INSOMNIA transcraneal magnetic Stimulation EEG abnormalities HYPEREXCItABILItY SLEEP Architecture Polysomnographic
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Correlative factors of poor prognosis and abnormal cellular immune function in patients with Alzheimer’s disease 被引量:2
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作者 Hua Bai Hong-Mei Zeng +2 位作者 Qi-Fang Zhang Yue-Zhi Hu Fei-Fei Deng 《World Journal of Clinical Cases》 SCIE 2024年第6期1063-1075,共13页
BACKGROUND Alzheimer’s disease(AD)is a serious disease causing human dementia and social problems.The quality of life and prognosis of AD patients have attracted much attention.The role of chronic immune inflammation... BACKGROUND Alzheimer’s disease(AD)is a serious disease causing human dementia and social problems.The quality of life and prognosis of AD patients have attracted much attention.The role of chronic immune inflammation in the pathogenesis of AD is becoming more and more important.AIM To study the relationship among cognitive dysfunction,abnormal cellular immune function,neuroimaging results and poor prognostic factors in patients.METHODS A retrospective analysis of 62 hospitalized patients clinical diagnosed with AD who were admitted to our hospital from November 2015 to November 2020.Collect cognitive dysfunction performance characteristics,laboratory test data and neuroimaging data from medical records within 24 h of admission,including Mini Mental State Examination Scale score,drawing clock test,blood T lymphocyte subsets,and neutrophils and lymphocyte ratio(NLR),disturbance of consciousness,extrapyramidal symptoms,electroencephalogram(EEG)and head nucleus magnetic spectroscopy(MRS)and other data.Multivariate logistic regression analysis was used to determine independent prog-nostic factors.the modified Rankin scale(mRS)was used to determine whether the prognosis was good.The correlation between drug treatment and prognostic mRS score was tested by the rank sum test.RESULTS Univariate analysis showed that abnormal cellular immune function,extrapyramidal symptoms,obvious disturbance of consciousness,abnormal EEG,increased NLR,abnormal MRS,and complicated pneumonia were related to the poor prognosis of AD patients.Multivariate logistic regression analysis showed that the decrease in the proportion of T lym-phocytes in the blood after abnormal cellular immune function(odd ratio:2.078,95%confidence interval:1.156-3.986,P<0.05)was an independent risk factor for predicting the poor prognosis of AD.The number of days of donepezil treatment to improve cognitive function was negatively correlated with mRS score(r=0.578,P<0.05).CONCLUSION The decrease in the proportion of T lymphocytes may have predictive value for the poor prognosis of AD.It is recommended that the proportion of T lymphocytes<55%is used as the cut-off threshold for predicting the poor prog-nosis of AD.The early and continuous drug treatment is associated with a good prognosis. 展开更多
关键词 Alzheimer’s disease Cellular immunity PROGNOSIS t lymphocytes magnetic resonance spectroscopy
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Abnormality of Magnetic Behavior and Resistivity of La_(0.7-x)Dy_x Sr_(0.3)MnO_3 (0.00≤x≤0.30)System at Low Temperature
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作者 刘宁 徐素军 +1 位作者 童伟 严国清 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期173-177,共5页
By measuring M-T curves, ρ-T curves and MR-T curves of the samples under different temperatures, the influence of Dy doping (0.00 ≤ x ≤0.30) on the magnetic and electric properties of La0.7-xDyxSr0.3MnO3 has been... By measuring M-T curves, ρ-T curves and MR-T curves of the samples under different temperatures, the influence of Dy doping (0.00 ≤ x ≤0.30) on the magnetic and electric properties of La0.7-xDyxSr0.3MnO3 has been studied. The experimental results show that, with the increase of the Dy content, the system undergoes a transition from long range ferromagnetic order to the cluster-spin glass state and further to antiferromagnetic order. For the samples with x=0.20 and 0.30, their magnetic behaviors are abnormal at low temperature, and their resistivities at low temperature have a minimum value. These peculiar phenomena not only come from the lattice effect induced by doping, but also from extra magnetic coupling induced by doping. 展开更多
关键词 MANGANItE abnormality of resistivity at low temperature Lattice effect Extra magnetic coupling
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Hepatic abnormal perfusion visible by magnetic resonance imaging in acute pancreatitis 被引量:5
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作者 Wei tang Xiao-Ming Zhang +1 位作者 Zhao-Hua Zhai Nan-Lin Zeng 《World Journal of Radiology》 CAS 2013年第12期491-497,共7页
AIM:to study the prevalence and patterns of hepatic abnormal perfusion(HAP)visible by magnetic resonance imaging(MRI)in acute pancreatitis(AP).METHODS:Enhanced abdominal MRI was performed on 51 patients with AP.these ... AIM:to study the prevalence and patterns of hepatic abnormal perfusion(HAP)visible by magnetic resonance imaging(MRI)in acute pancreatitis(AP).METHODS:Enhanced abdominal MRI was performed on 51 patients with AP.these patients were divided into two groups according to the MRI results:those with signs of gallstones,cholecystitis,common bile duct(CBD)stones or dilatation of the CBD on MRI and those without.the prevalence,shape and distribution of HAP in the two groups were analyzed and compared.the severity of AP was graded using the MR severity index(MRSI).the correlation between the MRSI and HAP was then analyzed.RESULTS:Of the 51 patients with AP,32(63%)showed at least one sign of gallbladder and CBD abnormalities on the MR images,while 19(37%)showed no sign of gallbladder or CBD abnormalities.Nineteen patients(37%)had HAP visible in the enhanced images,including strip-,wedge-or patch-shaped HAP distributed in the hepatic tissue adjacent to the gallbladder and left and right liver lobes.there were no significant differences in the prevalence of HAP(χ2=0.305,P=0.581>0.05)or HAP distribution in the liver(χ2=2.181,P=0.536>0.05)between patients with and without gallbladder and CBD abnormalities.there were no significant differences in the MRSI score between patients with and without HAP(t=0.559,P=0.552>0.05).HAP was not correlated with the MRSI score.CONCLUSION:HAP is common in patients with AP and appears strip-,patch-or wedge-shaped on MRI.HAP on MRI cannot be used to indicate the severity of AP. 展开更多
关键词 PANCREAtItIS HEPAtIC abnormAL PERFUSION magnetic resonance imaging GALLBLADDER
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Stress induced magnetic field abnormality 被引量:1
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作者 李路明 黄松岭 +2 位作者 王晓凤 李双寿 施克仁 《中国有色金属学会会刊:英文版》 CSCD 2003年第1期6-9,共4页
Residual stresses in ferromagnetic material affect the direction and structure of domains and generate magnetic field abnormality on the surface. In the formation of stress induced magnetic field, the influence of geo... Residual stresses in ferromagnetic material affect the direction and structure of domains and generate magnetic field abnormality on the surface. In the formation of stress induced magnetic field, the influence of geomagnetic field is unclear. Residual stress specimen was produced by tight matching of a round ring and a peg. The magnetic fields of contrast specimens, which were produced in geomagnetic field or in shielding geomagnetic field, were inspected with 8 mm lift-off. The results show that mean amplitude of magnetic field of the specimen produced in geomagnetic field is 0.85% larger than that of specimen produced in shielding geomagnetic field. So the formation of stress induced magnetic field abnormality above the surface of inspected ferromagnetic material geomagnetic field gives little contribution. 展开更多
关键词 非正态性磁场 残余应力 地磁场 铁磁体
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Effect of Mirror Magnetic Field on Abnormal Glow Discharge of Four-Anode Device
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作者 袁忠才 时家明 +1 位作者 许波 马柳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期446-449,共4页
Abstract In the four-anode device, the mirror magnetic field affects the characteristics of charged particles motion, so that the current-voltage relations of glow discharge are changed. Firstly, the discharge device ... Abstract In the four-anode device, the mirror magnetic field affects the characteristics of charged particles motion, so that the current-voltage relations of glow discharge are changed. Firstly, the discharge device is introduced, and the distribution of mirror magnetic field generated by the loops surrounding the discharge chamber is presented. Both the discharge current-voltage characteristics and the radial distributions of electron density are measured, respectively, with/without the magnetic field. When the discharge occurs in a 99.99% helium with a pressure ranging from 100 Pa to 800 Pa without magnetic field, the voltage, sustaining a certain abnormal glow discharge current, decreases with the increase in gas pressure. With a mirror magnetic field of certain intensity, the discharge voltage increases with the current in a rate slower than that without the magnetic field. Moreover, when the magnetic field intensity increases, the discharge voltage first decreases then increases. Simultaneously, the mirror magnetic field affects the moving characteristics of charged particles, and causes a more inhomogeneous electron density. 展开更多
关键词 current-voltage relations abnormal glow discharge four-anode device mirror magnetic field
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7T超高场磁共振颅内血管壁成像在缺血性脑卒中病因分型中的研究进展
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作者 张强 许晓泉 吴飞云 《磁共振成像》 CAS CSCD 北大核心 2024年第9期157-161,共5页
缺血性脑卒中的病因分型对临床治疗决策和预后判断有重要价值。近年来,随着高分辨率磁共振血管壁成像(high-resolution vessel wall magnetic resonance imaging,HR-VW-MRI)在脑卒中临床研究和实践中的应用增加,7 T MRI以其更高信噪比... 缺血性脑卒中的病因分型对临床治疗决策和预后判断有重要价值。近年来,随着高分辨率磁共振血管壁成像(high-resolution vessel wall magnetic resonance imaging,HR-VW-MRI)在脑卒中临床研究和实践中的应用增加,7 T MRI以其更高信噪比和更优图像质量,可发现脑血管早期、细微的病理变化,为深入了解各种脑血管疾病的病理机制提供了新思路。然而,超高场强也存在B1场不均、扫描时间长等技术挑战。本文就7 T HR-VW-MRI在缺血性卒中病因分型及临床应用中的进展进行综述,深入分析7 T HR-VW-MRI在提升临床诊断精确性与指导临床治疗中的潜在价值,为临床实践与科研探索提供参考。 展开更多
关键词 缺血性脑卒中 7 t 超高场 高分辨率磁共振血管壁成像 磁共振成像
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rTMS技术治疗对儿童孤独症谱系障碍合并睡眠障碍患者异常行为及睡眠状况的影响分析
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作者 苏静 苏秀琼 曾坤山 《中外医疗》 2024年第19期61-64,共4页
目的 研讨重复经颅磁刺激(Repetitive Transcranial Magnetic Stimulation, rTMS)技术治疗对孤独症谱系障碍(Autism Spectrum Disorder, ASDs)合并睡眠障碍患儿异常行为及睡眠状况的影响。方法 单纯随机选取2021年3月—2023年8月泉州市... 目的 研讨重复经颅磁刺激(Repetitive Transcranial Magnetic Stimulation, rTMS)技术治疗对孤独症谱系障碍(Autism Spectrum Disorder, ASDs)合并睡眠障碍患儿异常行为及睡眠状况的影响。方法 单纯随机选取2021年3月—2023年8月泉州市儿童医院收治的60例ASDs合并睡眠障碍的患儿为研究对象,结合随机数字表法分为两组,各30例。对照组接受常规康复治疗,观察组在对照组的基础上予以rTMS技术治疗,比较两组患儿不同治疗阶段的异常行为以及睡眠状况。结果 治疗后,观察组孤独症异常行为量表各项目得分、儿童睡眠习惯问卷(Children's Sleep Habits Questionnaire, CSHQ)各项目得分均低于对照组,差异有统计学意义(P均<0.05);观察组CSHQ总分为(43.02±4.19)分,低于对照组的(45.72±4.85)分,差异有统计学意义(t=2.307,P=0.024)。结论 rTMS技术用于ASDs合并睡眠障碍患儿的治疗,可辅助减轻患儿异常行为,改善其睡眠状况。 展开更多
关键词 儿童孤独症谱系障碍 睡眠障碍 重复经颅磁刺激 异常行为 睡眠状况
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飞利浦Ingenia 3.0 T磁共振成像仪射频系统故障三例
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作者 邵晓宁 吕佩颖 +1 位作者 刘良 程敬亮 《中国医疗设备》 2024年第6期178-182,共5页
磁共振成像无电离辐射且软组织成像效果较好,已成为常规体检和疾病诊断非常重要的医学影像诊疗技术之一。磁共振设备结构复杂,维修及维护成本较高,长期高负荷的运转会导致磁共振设备故障率增加。本文总结了本院飞利浦Ingenia 3.0 T磁共... 磁共振成像无电离辐射且软组织成像效果较好,已成为常规体检和疾病诊断非常重要的医学影像诊疗技术之一。磁共振设备结构复杂,维修及维护成本较高,长期高负荷的运转会导致磁共振设备故障率增加。本文总结了本院飞利浦Ingenia 3.0 T磁共振设备射频系统故障三例,包括de-tuned印刷电路板故障、射频放大器故障及体线圈故障。文中对三例飞利浦磁共振设备射频系统故障的表现进行了描述,对故障产生的原因进行了分析并介绍了故障排除过程,包括观察外观、提取后台日志参数、测量疑似受损部件指标、更换受损部件以及系统测试。通过深入分析射频系统故障案例,分享维修经验,以期提高设备使用率。 展开更多
关键词 3.0 t磁共振成像仪 射频系统 射频放大器 体线圈
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异常表达CD20的结外NK/T细胞淋巴瘤病理特点分析并文献复习 被引量:1
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作者 王红 任新瑜 贾丛伟 《诊断病理学杂志》 2024年第3期213-216,共4页
目的探索异常表达CD20的结外NK/T细胞淋巴瘤的病理形态特点、诊断要点及鉴别诊断。方法分析3例异常表达CD20的结外NK/T细胞淋巴瘤,结合病理形态特点、免疫表型及与其他形态学特点和免疫表型类似的淋巴瘤的鉴别诊断,并进行文献复习。结... 目的探索异常表达CD20的结外NK/T细胞淋巴瘤的病理形态特点、诊断要点及鉴别诊断。方法分析3例异常表达CD20的结外NK/T细胞淋巴瘤,结合病理形态特点、免疫表型及与其他形态学特点和免疫表型类似的淋巴瘤的鉴别诊断,并进行文献复习。结果异常表达CD20的结外NK/T细胞淋巴瘤形态学特点与普通型结外NK/T细胞淋巴瘤类似,免疫表型表现为部分T细胞标记阳性、CD56、细胞毒标记物、EBER ISH阳性、CD20弱-中等阳性,其余B细胞标记物CD79a、PAX-5均为阴性。其中2例肿瘤细胞阳性表达CD8。结论异常表达CD20的结外NK/T细胞淋巴瘤是一种罕见免疫表型的NK细胞源性淋巴瘤,需要综合分析抗体表达情况及和其他淋巴瘤进行鉴别诊断,免疫组织化学染色阳性模式以及多抗体联合应用对于明确诊断有重要作用。 展开更多
关键词 NK/t细胞淋巴瘤 异常表达 CD20 免疫组化
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Role of magnetic resonance cholangiopancreatography in diagnosing choledochal cysts: Case series and review 被引量:17
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作者 Vikas Y Sacher James S Davis +1 位作者 Danny Sleeman Javier Casillas 《World Journal of Radiology》 CAS 2013年第8期304-312,共9页
AIM:To determine the merits of magnetic resonance cholangiopancreatography(MRCP) as the primary diagnostic test for choledochal cysts(CC’s).METHODS:Between 2009 and 2012,patients who underwent MRCP for perioperative ... AIM:To determine the merits of magnetic resonance cholangiopancreatography(MRCP) as the primary diagnostic test for choledochal cysts(CC’s).METHODS:Between 2009 and 2012,patients who underwent MRCP for perioperative diagnosis were identified.Demographic information,clinical characteristics,and radiographic findings were recorded.MRCP results were compared with intraoperative findings.A PubMed search identified studies published between 1996-2012,employing MRCP as the primary preoperative imaging and comparing results with either endoscopic retrograde cholangiopancreatography(ERCP) or operative findings.Detection rates for CC’s and abnormal pancreaticobiliary junction(APBJ) were calculated.In addition detection rates for clinically related biliary pathology like choledocholithiasis and cholangiocarcinomas in patients diagnosed with CC’s were also evaluated.RESULTS:Eight patients were identified with CC’s.Six patients out of them had typeⅣCC’s,1 had type I and 1 had a new variant of choledochal cyst with confluent dilatation of the common bile duct(CBD) and cystic duct.Seven patients had an APBJ and 3 of those had a long common-channel.Gallstones were found in 2 patients,1 had a CBD stone,and 1 pancreatic-duct stone was also detected.In all cases,MRCP successfully identified the type of CC’s,as well as APBJ with ductal stones.From analyzing the literature,we found that MRCP has 96%-100% detection rate for CC’s.Additionally,we found that the range for sensitivity,specificity,and diagnostic accuracy was 53%-100%,90%-100% and 56%-100% in diagnosing APBJ.MRCP’s detection rate was 100% for choledocholithiasis and 87% for cholangiocarcinomas with concurrent CC’s.CONCLUSION:After initial ultrasound and computed tomography scan,MRCP should be the next diagnostic test in both adult and pediatric patients.ERCP should be reserved for patients where therapeutic intervention is needed. 展开更多
关键词 magnetic resonance CHOLANGIOPANCREAtOGRAPHY Choledochal CYSt abnormAL pancreaticobiliary JUNCtION DIAGNOStIC test CHOLEDOCHOLItHIASIS Cholangiocarcinomas
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Characterization of the Elastic-plastic Region Based on Magnetic Memory Effect 被引量:3
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作者 LENG Jiancheng XU Minqiang +1 位作者 LI Jianwei ZHANG Jiazhong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期532-536,共5页
Detecting stress concentration, especially critical stress state leading to structure damage or failure, is one of the most important tasks of equipment diagnosis. Metal magnetic memory technique needs further researc... Detecting stress concentration, especially critical stress state leading to structure damage or failure, is one of the most important tasks of equipment diagnosis. Metal magnetic memory technique needs further research to evaluate stress concentration quantitatively due to ambiguous physical mechanism, though it has potential to detect early defects in ferromagnetic materials. Mild Q235 steel defective specimens in demagnetization state were loaded in tension up to visible necking, with magnetic memory signals measurement made at increasing stress levels. Magnetic signals varied greatly under first several loadings and subsequently tended to stability in the elastic region, which showed that the magnetization always approaches the anhysteretic magnetization curve and was explained by the theory of magnetomechanical effect. In the plastic stage, an abnormal wave occurred in the stress concentration zone and its height value was sensitive to plastic deformation levels and dependent on the distance between the probe and defect, in accordance with the simulation results based on the magnetic dipole model. Different magnetic signal characteristics in the elastic-plastic region indicate that the magnetic memory technique can identify macroyielding and early damage, which is of profound significance for ensuring safe operation of equipment in service. 展开更多
关键词 metal magnetic memory plastic deformation magnetomechanical effect magnetic dipole model abnormal wave
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Magnetic Resonance Imaging and Histopathological Analysis of Experimental Muscle Injuries in a Rabbit 被引量:7
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作者 YAN Dong ZHANG Jing +4 位作者 LIANG Wei SUN Jing LIU Bao Yue TIAN Wei CHENG Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第10期841-848,共8页
Objective To investigate the correlation of magnetic resonance imaging (MRI) with histopathologica changes, and to evaluate T2 mapping in assessing muscle trauma in a rabbit model of muscle injury. Methods We divide... Objective To investigate the correlation of magnetic resonance imaging (MRI) with histopathologica changes, and to evaluate T2 mapping in assessing muscle trauma in a rabbit model of muscle injury. Methods We divided 35 rabbits into seven groups that each represented a different time point after intramuscular hemorrhage and muscle injury. Hemorrhage was created by injecting autologous blood into the left legs, and muscle injury was created by scalpel incision of the biceps femoris of the right legs. At different time points, the rabbits underwent Tl-weighted imaging and T2-weighted imaging (TzWl and T2Wl) and T2 mapping. T2 relaxation times were measured, and the corresponding samples were evaluated for pathological changes. Results After 2 h, the intramuscular hemorrhage model demonstrated an increased signal intensity on both TlWl and T2Wl. Histological examination showed erythrocytes within the muscle bundle. On days 1 and 3, the MRI signals were decreased, and there were no significant changes after day 7. From 2 h to 3 days, the muscle-injury model showed a high signal on both TzWl and T2Wl. Corresponding pathological changes included rupture and edema of muscle fibers, and inflammation. The abnormal signals were reduced on day 7. After day 14, the T2Wl intensity remained high. TlWl showed no abnormal changes, but some models showed a high signal, representing fresh bleeding and fatty tissue. T2 relaxation times were significantly different between the central and marginal regions, and between the marginal and normal regions. Conclusion MRI clearly demonstrates intramuscular hemorrhage and muscle injury, which correlate well with histopathological changes. Tz mapping is useful in assessing the extent of injury. 展开更多
关键词 Muscle injury Intramuscular hemorrhage magnetic resonance imaging t2 mapping
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T2* magnetic resonance imaging of the liver in thalassemic patients in Iran 被引量:8
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作者 Farhad Zamani Sara Razmjou +3 位作者 Shahram Akhlaghpoor Seyyedeh-Masoomeh Eslami Azita Azarkeivan Afsaneh Amiri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第4期522-525,共4页
AIM: To investigate the accuracy of T2*-weighted magnetic resonance imaging (MRI T2*) in the evaluation of iron overload in beta-thalassemia major patients. METHODS: In this cross-sectional study, 210 patients with be... AIM: To investigate the accuracy of T2*-weighted magnetic resonance imaging (MRI T2*) in the evaluation of iron overload in beta-thalassemia major patients. METHODS: In this cross-sectional study, 210 patients with beta-thalassemia major having regular blood transfusions were consecutively enrolled. Serum ferritin levels were measured, and all patients underwent MRI T2* of the liver. Liver biopsy was performed in 53 patients at an interval of no longer than 3 mo after the MRIT2* in each patient. The amount of iron was assessed in both MRI T2* and liver biopsy specimens of each patient. RESULTS: Patients’ ages ranged from 8 to 54 years with a mean of 24.59 ± 8.5 years. Mean serum ferritin level was 1906 ± 1644 ng/mL. Liver biopsy showed a moderate negative correlation with liver MRI T2* (r = -0.573, P = 0.000) and a low positive correlation with ferritin level (r = 0.350, P = 0.001). Serum ferritin levels showed a moderate negative correlation with liver MRI T2* values (r = -0.586, P = 0.000). CONCLUSION: Our study suggests that MRI T2* is a non-invasive, safe and reliable method for detecting iron load in patients with iron overload. 展开更多
关键词 t2*-weighted magnetic resonance imaging LIVER Iron overload Major thalassemia FERRItIN
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磁共振多序列成像在结肠癌T分期中的诊断性能探究
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作者 于庆 杨春英 靳海英 《中国CT和MRI杂志》 2024年第9期137-139,共3页
目的探讨磁共振多序列成像(magnetic resonance imaging,MRI)在结肠癌(colon cancer,CC)T分期的诊断性能。方法回顾性收集河南大学淮河医院于2022年1月至2022年12月收治的结肠癌患者32例。所有结肠癌患者术前均接受MRI检查。依次使用T2... 目的探讨磁共振多序列成像(magnetic resonance imaging,MRI)在结肠癌(colon cancer,CC)T分期的诊断性能。方法回顾性收集河南大学淮河医院于2022年1月至2022年12月收治的结肠癌患者32例。所有结肠癌患者术前均接受MRI检查。依次使用T2加权成像快速自旋回波序列(T2 weighted imaging,T2WI)快速自旋回波序列(冠状面、轴面、矢状面)、扩散加权成像序列(diffusion weighted imaging,DWI)序列(轴面)及对比增强T1加权成像(T1 weighted imaging,T1WI)序列(冠状面)完成对全腹部和肝脏的扫描。分别对肿瘤的位置、肠壁浸润深度及是否侵犯浆膜层进行记录,并与术后病理结果进行比较。采用受试者工作(receiver operating characteristic,ROC)曲线分析MRI中T2WI序列、对比增强T1WI序列对术前CC患者T分期的诊断效能。结果MRI中T2WI序列对结肠癌患者T分期的准确性、敏感性、特异性分别为81.25%,84.21%,66.67%。此外,MRI中增强T1WI序列的准确性、敏感性、特异性分别为93.75%,94.12%,75%。结论MRI是结肠癌患者术前T分期检测的一种潜在的和有价值的影像学方法,且T1WI具有更高的诊断价值。 展开更多
关键词 结肠癌 核磁共振成像 t分期
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Cutting edge clinical applications in cardiovascular magnetic resonance 被引量:1
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作者 Carlo N De Cecco Giuseppe Muscogiuri +1 位作者 Akos Varga-Szemes U Joseph Schoepf 《World Journal of Radiology》 CAS 2017年第1期1-4,共4页
Today, the use of cardiovascular magnetic resonance(CMR) is widespread in clinical practice. The increased need to evaluate of subtle myocardial changes, coronary artery anatomy, and hemodynamic assessment has prompte... Today, the use of cardiovascular magnetic resonance(CMR) is widespread in clinical practice. The increased need to evaluate of subtle myocardial changes, coronary artery anatomy, and hemodynamic assessment has prompted the development of novel CMR techniques including T1 and T2 mapping, non-contrast angiography and four dimensional(4D) flow. T1 mapping is suitable for diagnosing pathologies affecting extracellular volume such as myocarditis, diffuse myocardial fibrosis and amyloidosis, and is a promising diagnostic tool for patients with iron overload and Fabry disease. T2 mapping is useful in depicting acute myocardial edema and estimating the amount of salvageable myocardium following an ischemic event. Novel angiography techniques, such as the selfnavigated whole-heart or the quiescent-interval singleshot sequence, enable the visualization of the great vessels and coronary artery anatomy without the use of contrast material. The 4D flow technique overcomes the limitations of standard phase-contrast imaging and allows for the assessment of cardiovascular hemodynamics in the great arteries and flow patterns in the cardiac chambers. In conclusion, the future of CMR is heading toward a more reliable quantitative assessment of the myocardium, an improved non-contrast visualization of the coronary artery anatomy, and a more accurate evaluation of the cardiac hemodynamics. 展开更多
关键词 Cardiac magnetic resonance t1 mapping magnetic resonance angiography t2 mapping Four dimensional flow
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A decomposition method of nuclear magnetic resonance T2 spectrum for identifying fluid properties 被引量:4
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作者 ZHONG Jibin YAN Ronghui +3 位作者 ZHANG Haitao FENG Yihan LI Nan LIU Xingjun 《Petroleum Exploration and Development》 2020年第4期740-752,共13页
Based on analysis of NMR T2 spectral characteristics,a new method for identifying fluid properties by decomposing T2 spectrum through signal analysis has been proposed.Because T2 spectrum satisfies lognormal distribut... Based on analysis of NMR T2 spectral characteristics,a new method for identifying fluid properties by decomposing T2 spectrum through signal analysis has been proposed.Because T2 spectrum satisfies lognormal distribution on transverse relaxation time axis,the T2 spectrum can be decomposed into 2 to 5 independent component spectra by fitting the T2 spectrum with Gauss functions.By analyzing the free relaxation response characteristics of crude oil and formation water,the dynamic response characteristics of the core mutual drive between oil and water,the petrophysical significance of each component spectrum is clarified.T2 spectrum can be decomposed into clay bound water component spectrum,capillary bound fluid component spectrum,micropores fluid component spectrum and macropores fluid component spectrum.According to the nature of crude oil in the target area,the distribution range of T2 component spectral peaks of oil-bearing reservoir is 165-500 ms on T2 time axis.This range can be used to accurately identify fluid properties.This method has high adaptability in identifying complex oil and water layers in low porosity and permeability reservoirs. 展开更多
关键词 nuclear magnetic resonance free relaxation t2 spectrum decomposition method fitted t2 spectrum component spectrum fluid identification
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Quantitative multiparametric magnetic resonance imaging can aid non-alcoholic steatohepatitis diagnosis in a Japanese cohort 被引量:2
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作者 Kento Imajo Louise Tetlow +14 位作者 Andrea Dennis Elizabeth Shumbayawonda Sofia Mouchti Timothy J Kendall Eve Fryer Shogi Yamanaka Yasushi Honda Takaomi Kessoku Yuji Ogawa Masato Yoneda Satoru Saito Catherine Kelly Matt D Kelly Rajarshi Banerjee Atsushi Nakajima 《World Journal of Gastroenterology》 SCIE CAS 2021年第7期609-623,共15页
BACKGROUND Non-invasive assessment of non-alcoholic steatohepatitis(NASH)is increasing in desirability due to the invasive nature and costs associated with the current form of assessment;liver biopsy.Quantitative mult... BACKGROUND Non-invasive assessment of non-alcoholic steatohepatitis(NASH)is increasing in desirability due to the invasive nature and costs associated with the current form of assessment;liver biopsy.Quantitative multiparametric magnetic resonance imaging(mpMRI)to measure liver fat(proton density fat fraction)and fibroinflammatory disease[iron-corrected T1(cT1)],as well as elastography techniques[vibration-controlled transient elastography(VCTE)liver stiffness measure],magnetic resonance elastography(MRE)and 2D Shear-Wave elastography(SWE)to measure stiffness and fat(controlled attenuated parameter,CAP)are emerging alternatives which could be utilised as safe surrogates to liver biopsy.AIM To evaluate the agreement of non-invasive imaging modalities with liver biopsy,and their subsequent diagnostic accuracy for identifying NASH patients.METHODS From January 2019 to February 2020,Japanese patients suspected of NASH were recruited onto a prospective,observational study and were screened using noninvasive imaging techniques;mpMRI with LiverMultiScan®,VCTE,MRE and 2DSWE.Patients were subsequently biopsied,and samples were scored by three independent pathologists.The diagnostic performances of the non-invasive imaging modalities were assessed using area under receiver operating characteristic curve(AUC)with the median of the histology scores as the gold standard diagnoses.Concordance between all three independent pathologists was further explored using Krippendorff’s alpha(a)from weighted kappa statistics.RESULTS N=145 patients with mean age of 60(SD:13 years.),39%females,and 40%with body mass index≥30 kg/m2 were included in the analysis.For identifying patients with NASH,MR liver fat and cT1 were the strongest performing individual measures(AUC:0.80 and 0.75 respectively),and the mpMRI metrics combined(cT1 and MR liver fat)were the overall best non-invasive test(AUC:0.83).For identifying fibrosis≥1,MRE performed best(AUC:0.97),compared to VCTE-liver stiffness measure(AUC:0.94)and 2D-SWE(AUC:0.94).For assessment of steatosis≥1,MR liver fat was the best performing non-invasive test(AUC:0.92),compared to controlled attenuated parameter(AUC:0.75).Assessment of the agreement between pathologists showed that concordance was best for steatosis(a=0.58),moderate for ballooning(a=0.40)and fibrosis(a=0.40),and worst for lobular inflammation(a=0.11).CONCLUSION Quantitative mpMRI is an effective alternative to liver biopsy for diagnosing NASH and non-alcoholic fatty liver,and thus may offer clinical utility in patient management. 展开更多
关键词 Corrected t1 Fibro-inflammation Non-invasive imaging Non-alcoholic steatohepatitis Multiparametric magnetic resonance imaging Non-alcoholic fatty liver disease
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基于颗粒酶B启动子的磁共振报告基因成像监测CAR-T细胞激活状态
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作者 倪晓英 秦勇 +5 位作者 贺小娅 黄杰 张湘敏 祝慧如 胡倩 蔡金华 《陆军军医大学学报》 CAS CSCD 北大核心 2024年第17期1959-1968,共10页
目的利用颗粒酶B(granzyme B,GB)启动子控制铁蛋白(ferritin heavy chain,FTH1)报告基因表达,探讨通过磁共振成像(magnetic resonance imaging,MRI)监测嵌合抗原受体T细胞(chimeric antigen receptor T cells,CAR-T细胞)激活状态的可行... 目的利用颗粒酶B(granzyme B,GB)启动子控制铁蛋白(ferritin heavy chain,FTH1)报告基因表达,探讨通过磁共振成像(magnetic resonance imaging,MRI)监测嵌合抗原受体T细胞(chimeric antigen receptor T cells,CAR-T细胞)激活状态的可行性。方法通过Ficoll密度梯度离心法以及流式分选得到细胞毒性T淋巴细胞(cytotoxic T lymphocytes,CTLs)。将GB启动子和FTH1基因连接,连同二唾液酸神经节苷脂(disialoganglioside 2,GD2)嵌合抗原受体(chimeric antigen receptor,CAR)以慢病毒为载体转入CTLs,构建GD2-CAR-T/pGB-FTH1细胞,以GD2-CAR-T/pCMV-FTH1、GD2-CAR-T和T细胞为对照。CytoTox96@非放射性细胞毒性检测各组细胞与人神经母细胞瘤细胞(SK-N-SH)共培养后的杀伤效果,ELISA检测共孵育因子以及GB分泌量,Western blot、普鲁士蓝染色、细胞MRI检测共培养后FTH1基因的表达。结果成功获得CTLs并构建GD2-CAR-T/pGB-FTH1、GD2-CAR-T/pCMV-FTH1、GD2-CAR-T细胞,3组细胞对肿瘤细胞杀伤效果、共孵育因子以及GB分泌量均显著高于T细胞组,GB表达水平在与SK-N-SH细胞共培养后1 d最高,3 d和7 d依次降低。GD2-CAR-T/pGB-FTH1组FTH1相对表达量以及铁含量变化趋势与GB表达一致,MRI信号呈逐渐升高趋势。GD2-CAR-T/pCMV-FTH1组FTH1相对表达量、铁含量及MRI信号在各时间点均无显著差异。GD2-CAR-T和T细胞组无明显FTH1表达及聚铁效应。结论基于GB启动子的MRI报告基因成像可实时反映CAR-T细胞的GB表达水平和肿瘤杀伤作用,为CAR-T治疗提供了一种监测细胞激活状态的可视化手段。 展开更多
关键词 颗粒酶B 铁蛋白 报告基因 磁共振成像 嵌合抗原受体t细胞 二唾液酸神经节苷脂
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