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1.
目的 探讨痉挛型偏瘫患儿手节区(HKR)形态学变化的MRI征象。方法 回顾性病例对照研究。纳入2016年3月—2019年7月西安交通大学第一附属医院儿科确诊并行头颅MR检查的痉挛型偏瘫患儿14例为病例组,其中男8例、女6例,年龄(3.9±2.1)岁;MRI主要表现为脑室周围白质软化11例,脑灰质损伤4例,其中1例白质灰质均有损伤。另纳入28例健康儿童作为对照组,其中男16例、女12例,年龄(4.1±2.0)岁,其年龄、性别构成和双侧半球HKR类型均与病例组相匹配。基于MR 3D-T1WI数据,在HKR的最佳评估层面(以在T1WI轴位影像上观察到双侧额上沟位于双侧半球前中部、中央沟深达同侧半球内1/3处,同时可良好观察到HKR形态的层面为最佳评估层面)测量及计算2组受试者两侧半球HKR皮层厚度、高度、基底宽度、白质高度、高度与皮层厚度之比和高度与基底宽度之比等形态学指标。采用配对t检验、独立样本t检验或秩和检验,对各指标观察结果进行组内、组间统计学分析比较。采用组内相关系数检验观察者间、观察者内测量的一致性。结果 2组儿童年龄、性别和双侧HKR类型等基线资料比较,差异均无统计学意义(P值均>0.05)。病例组患儿受累侧HKR高度/皮层厚度(3.41±1.03)和HKR白质高度/皮层厚度(2.41±1.03)均小于未受累侧半球HKR(分别为3.96±1.17和2.96±1.17),差异均有统计学意义(t=2.49、2.49,P值均<0.05);其余各指标组内比较,差异无统计学意义(P值均>0.05)。病例组患儿受累侧半球HKR高度(7.13±1.40)mm、HKR白质高度(4.89±1.47)mm、HKR高度/皮层厚度(3.41±1.03)和HKR白质高度/皮层厚度(2.41±1.03)均小于对照组相对应一侧[(8.65±1.01) mm,(6.77±0.99) mm,4.70±0.79和3.70±0.79],差异有统计学意义(t=2.91、3.58、3.71、3.71,P值均<0.05);其余各指标组间比较,差异无统计学意义(P值均>0.05)。结论 痉挛型偏瘫患儿受累侧半球HKR皮层厚度、基底宽度改变不明显,但白质高度减小。  相似文献   
2.
视觉通路包括视神经、视交叉、视束、视放射及视皮质。常规磁共振检查技术难以发现视路损伤后白质纤维微结构改变,眼科学检查也存在一定的局限性及主观性,且不能探测后视路的变化。弥散张量成像(diffusion tensor imaging,DTI)作为一种新兴的磁共振成像技术,通过各种后处理分析方法结合不同的参数进行分析,可提供组织的微结构信息,并能够直观显示活体白质纤维束,在无创地探索疾病的神经病理机制、评估预后方面起着重要的作用。近年来随着DTI后处理方法的不断创新,其在视路损伤中的研究越来越多。本文在介绍DTI的主要参数及常见脑白质微结构分析方法的同时,阐述了其在视路损伤研究中的应用,并进一步对各种分析方法的优缺点进行总结。  相似文献   
3.
IntroductionExchange transfusion (ECT) is one of effective treatments for rapid reduction of the bilirubin serum levels. The main purpose of this study was to offer greater insights into the effects of ECT on the hematologic factors and bilirubin in neonatal hyperbilirubinemia.MethodsThis cross-sectional study was performed on 380 neonates over 35 gestational weeks, and 2–14 days old with a bilirubin of above 17 mg/dl who had undergone ECT at Ghaem Hospital of Mashhad in Iran from 2011 to 2021. Blood samples were examined before, immediately after, 6 h and 60 h after ECT for complete blood cell count (CBC), platelet count and bilirubin serum level analysis.ResultsIn this study, the mean age of neonates was 5.21 ± 3.55 days with a mean birth weight of 2810 ± 710 gr. The mean platelet count (PLT), white blood cell (WBC) and the serum level of bilirubin were estimated at 260,000/mm2, 12,400/mm2, 23 mg/dl before ECT and 97,000/mm2, 7370//mm2 and 12.6 mg/dl immediately after ECT, respectively (P-value <0.001).ConclusionThe results indicated that the mean serum levels of bilirubin, platelets, and leukocytes dropped to 55%, 30%, and 60% of their baseline levels before ECT, respectively, but they all spiked after ECT.  相似文献   
4.
《Indian heart journal》2022,74(6):474-477
Background and objectivesAmbulatory blood pressure (BP) monitoring has become useful in the diagnosis and management of hypertensive individuals. In this study we tried to know the role of office and ambulatory BP in treated hypertensive patients.Methods and patientsProspective cohort of 561 treated hypertensive patients were enrolled in the study. Hypertension definitions were according to JNC 8 classification. Office BP and ambulatory BP monitoring was done according to defined protocol.ResultsFrom a subgroup of 158 treated hypertensive patients, 91(16.2%) patients were having white coat hypertension (p value 0.00 by Pearson chi square test). In a subset of 403 patients who were having controlled BP on the day of enrolment as well as on the day of attaching ambulatory BP monitor; 98 (17.4%) patients were having masked uncontrolled hypertension (MUCH). In addition there was very significant percentage of non-dippers and reverse dippers. In our study we found that office BP has a moderate to low specificity and sensitivity and low negative predictive value for overall control in treated hypertensive patients.ConclusionAmbulatory BP monitoring should be included in the management protocol of treated hypertensive patients, for the optimal BP control.  相似文献   
5.
Severe postnatal systemic infection is highly associated with persistent disturbances in brain development and neurobehavioral outcomes in survivors of preterm birth. However, the contribution of less severe but prolonged postnatal infection and inflammation to such disturbances is unclear. Further, the ability of modern imaging techniques to detect the underlying changes in cellular microstructure of the brain in these infants remains to be validated. We used high-field ex-vivo MRI, neurohistopathology, and behavioral tests in newborn rats to demonstrate that prolonged postnatal systemic inflammation causes subtle, persisting disturbances in brain development, with neurodevelopmental delays and mild motor impairments. Diffusion-tensor MRI and neurite orientation dispersion and density imaging (NODDI) revealed delayed maturation of neocortical and subcortical white matter microstructure. Analysis of pyramidal neurons showed that the cortical deficits involved impaired dendritic arborization and spine formation. Analysis of oligodendrocytes showed that the white matter deficits involved impaired oligodendrocyte maturation and axonal myelination. These findings indicate that prolonged postnatal inflammation, without severe infection, may critically contribute to the diffuse spectrum of brain pathology and subtle long-term disability in preterm infants, with a cellular mechanism involving oligodendrocyte and neuronal dysmaturation. NODDI may be useful for clinical detection of these microstructural deficits.  相似文献   
6.
Disrupted blood–brain barrier (BBB) in patients with ischemic stroke plays a critical role in malignant middle cerebral artery infarction (MMI) development.Cerebral white matter changes (WMC), particularly in the deep subcortical area or in severe one, may be also underlain by disrupted BBB. It is unclear whether the presence of WMC with potential premorbid disruption of BBB makes patients susceptible to MMI. Therefore, this study aimed to clarify any putative relationship between the MMI and WMC in terms of their severity and locations.In this case–control study, patients with infarction in the middle cerebral artery territory were retrospectively reviewed. Brain magnetic resonance images were analyzed according to Fazekas scale, and identified WMC were divided into periventricular WMC (PV-WMC) and deep subcortical WMC (deep-WMC). Patients were scored as having WMC, PV-WMC, deep-WMC, severe PV-WMC, and severe deep-WMC according to the severity and locations. Patients were defined as having MMI if either a progressive conscious disturbance or signs of uncal herniation was recorded in combination with a midline shift >5 mm identified on the follow-up computed tomography.Among 297 patients admitted between July 2009 and February 2015, 92 patients were eligible for final analysis. Compared to patients without MMI, patients with MMI had a higher score of National Institutes of Health Stroke Scale, a larger infarct volume, and an increasingly greater proportion of severe PV-WMC, deep-WMC, and severe deep-WMC, respectively. After adjustment for sex, age, infarct volume, and history of hypertension, severe deep-WMC (odds ratio [OR] = 6.362, 95% confidence interval [CI] = 1.444–28.023, P = .0144) and severe PV-WMC (odds ratio = 5.608, 95% confidence interval = 1.107–28.399, P = .0372) were significantly associated with MMI development.MMI and WMC are significantly associated such that MMI development is more likely when PV-WMC or deep-WMC is more severe. We hypothesize that Fazekas scale-defined severe deep-WMC and PV-WMC may be considered as clinically approachable predictors of MMI development. These findings support that the WMC with potential premorbid disrupted BBB may make patients susceptible to MMI, and further prospective study should be conducted to clarify this hypothesis.  相似文献   
7.
糖尿病寒热错杂、虚实兼夹,可分为湿热蕴脾证、肝郁气滞证、肝胃郁热证、胃热阴虚证、肠道湿热证、血脉瘀滞证等证型,治疗当运用和法辛开苦降、疏肝理气、清泻热结、滋阴清热、清热利湿、活血化瘀,选用半夏泻心汤、四逆散、大黄黄连泻心汤、大柴胡汤、白虎加人参汤、葛根芩连汤、桃核承气汤以调整气机、平调寒热、补虚泻实,并在药物治疗的基础上注重饮食、运动,调和身心。使机体恢复"阴平阳秘"的状态,"阴阳自和者必自愈"。  相似文献   
8.
目的通过meta分析评价颞极和外囊白质高信号(white matter hyperintensities,WMHs)对诊断伴皮质下梗死和白质脑病的常染色体显性遗传脑动脉病(cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy,CADASIL)患者的临床价值。方法检索PubMed、Cochrane、Embase、维普中文科技期刊数据库、中国生物医学文献数据库、中国知网、万方数据服务平台等数据库,收集颞极和外囊WMHs诊断CADASIL患者的相关文献,检索时限均从建库至2020年4月1日。使用诊断准确性研究质量评价工具QUADAS-2进行文献质量评价。采用Stata 15.1软件进行统计分析,拟合综合受试者工作特征(summary receiver operating characteristic,SROC)曲线,合并诊断效应量,评估颞极和外囊WMHs对CADASIL的诊断价值。结果纳入9篇文献共10项研究,累计880例患者。颞极和外囊WMHs的合并敏感性分别为0.67[95%置信区间(confidence interval,CI)0.54~0.78]和0.84(95%CI 0.72~0.91),合并特异性分别为0.64(95%CI 0.47~0.78)和0.44(95%CI 0.36~0.53),合并阳性似然比分别为1.9(95%CI 1.4~2.6)和1.5(95%CI 1.2~1.8),合并阴性似然比分别为0.51(95%CI 0.42~0.63)和0.37(95%CI 0.20~0.69),合并诊断优势比分别为4(95%CI 3~5)和4(95%CI 2~9),SROC曲线下面积分别为0.71(95%CI 0.66~0.74)和0.62(95%CI 0.58~0.66)。结论颞极和外囊WMHs对CADASIL的诊断价值有限,在临床诊断过程中需要综合考虑其他因素。  相似文献   
9.
Diffusion magnetic resonance imaging (dMRI) provides indirect measures of white matter microstructure that can be used to make inferences about structural connectivity within the brain. Over the last decade, a growing literature of cross-sectional and longitudinal studies have documented relationships between dMRI indices and cognitive development. In this review, we provide a brief overview of dMRI methods and how they can be used to study white matter and connectivity and review the extant literature examining the links between dMRI indices and executive functions during development. We explore the links between white matter microstructure and specific executive functions: inhibition, working memory and cognitive shifting, as well as performance on complex executive function tasks. Concordance in findings across studies are highlighted, and potential explanations for discrepancies between results, together with challenges with using dMRI in child and adolescent populations, are discussed. Finally, we explore future directions that are necessary to better understand the links between child and adolescent development of structural connectivity of the brain and executive functions.  相似文献   
10.
Language acquisition is of central importance to child development. Although this developmental trajectory is shaped by experience postnatally, the neural basis for language emerges prenatally. Thus, a fundamental question remains: do structural foundations for language in infancy predict long-term language abilities? Longitudinal investigation of 40 children from infancy to kindergarten reveals that white matter in infancy is prospectively associated with subsequent language abilities, specifically between: (i) left arcuate fasciculus and phonological awareness and vocabulary knowledge, (ii) left corticospinal tract and phonological awareness, and bilateral corticospinal tract with phonological memory; controlling for age, cognitive, and environmental factors. Findings link white matter in infancy with school-age language abilities, suggesting that white matter organization in infancy sets a foundation for long-term language development.  相似文献   
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