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11.
Subacute sclerosing panencephalitis (SSPE) is a rare, slowly progressing but invariably fatal disease that is related to a prior measles virus infection and most commonly affects paediatric patients. Magnetic resonance (MR) imaging is the modality of choice for determining such changes in white matter. SSPE typically demonstrates bilateral but asymmetric periventricular and subcortical white matter involvement. We herein report a rare case of unilateral white matter involvement in a 13-year-old boy with SSPE that closely simulated Rasmussen’s encephalitis. To the best of our knowledge, this is the first report of an atypical presentation on MR imaging in which SSPE was a rare cause of unilateral brain parenchymal involvement in a patient with intractable seizures.  相似文献   
12.
目的:探究超脉冲CO2点阵激光联合富血小板血浆(PRP)治疗面部痤疮凹陷性瘢痕的疗效。方法:72例面部痤疮凹陷性瘢痕患者,随机分为观察组(36例)和对照组(36例)。对照组采用超脉冲CO2点阵激光治疗,观察组采用超脉冲CO2点阵激光联合PRP治疗。比较两组患者的灰度差异、时间指标、瘢痕程度、疼痛、不良反应及视觉评估。结果:观察组的并发症发生率为11.11%,低于对照组的36.11%,差异具有统计学意义(P<0.05)。治疗后,两组患者的灰度差异率均减小,且观察组患者的灰度差异率显著低于对照组,差异具有统计学意义(P<0.05)。治疗后,观察组的炎性渗出时间、红肿时间、愈合时间、停工时间及瘢痕程度评分均低于对照组,差异均具有统计学意义(P<0.05);但疼痛度评分组间比较,差异无统计学意义(P>0.05)。结论:超脉冲CO2点阵激光联合PRP治疗面部痤疮凹陷性瘢痕效果较好,可有效降低瘢痕程度,减少治疗时间及并发症的发生,帮助患者迅速回归正常工作与生活,值得临床推广使用。  相似文献   
13.
目的 比较枸橼酸咖啡因和氨茶碱对早产儿神经行为发育的影响,为早产儿早期合理干预提供临床依据。方法 选择2014年6月-2018年6月在中国西电集团医院新生儿科住院接受枸橼酸咖啡因治疗的原发性呼吸暂停(AOP)早产儿62例作为研究组;2011 年 12 月-2014年5月同在中国西电集团医院新生儿科住院采用氨茶碱治疗的AOP患儿69例作为对照组。出生3~8 d及矫正胎龄40周时分别行头颅MRI检查,评估脑白质损伤(WMD)并进行两组比较;6个月及12个月时应用Gesell婴幼儿发育量表测试比较两组神经行为发育水平。结果 两组患儿在性别、出生胎龄及体重、产前孕母糖皮质激素应用及分娩方式、5 min Apgar评分、辅助通气和表面活性物质的应用等方面差异均无统计学意义(P>0.05)。首次头颅MRI显示两组患儿WMD差异无统计学意义(P>0.05)。矫正胎龄40周时头颅MRI显示,咖啡因组WMD较氨茶碱组明显改善,差异有统计学意义(P<0.05);且6个月及12个月时Gessell婴幼儿发育量表测试,随访至校正6月龄时,咖啡因组患儿的大运动、精细运动及个人-社交评分均高于氨茶碱组(P<0.05);随访至校正12月龄时,咖啡因组患儿的大运动、精细运动、语言、适应性评分均高于氨茶碱组(P<0.05)。结论 枸橼酸咖啡可明显改善AOP患儿6个月及12个月时的神经行为发育。  相似文献   
14.
BACKGROUND: Although pedophilia is of high public concern, little is known about underlying neural mechanisms. Although pedophilic patients are sexually attracted to prepubescent children, they show no sexual interest toward adults. This study aimed to investigate the neural correlates of deficits of sexual and emotional arousal in pedophiles. METHODS: Thirteen pedophilic patients and 14 healthy control subjects were tested for differential neural activity during visual stimulation with emotional and erotic pictures with functional magnetic resonance imaging. RESULTS: Regions showing differential activations during the erotic condition comprised the hypothalamus, the periaqueductal gray, and dorsolateral prefrontal cortex, the latter correlating with a clinical measure. Alterations of emotional processing concerned the amygdala-hippocampus and dorsomedial prefrontal cortex. CONCLUSIONS: Hypothesized regions relevant for processing of erotic stimuli in healthy individuals showed reduced activations during visual erotic stimulation in pedophilic patients. This suggests an impaired recruitment of key structures that might contribute to an altered sexual interest of these patients toward adults.  相似文献   
15.
Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons.  相似文献   
16.
Neurochemical studies on the mesolimbic circuitry of antinociception   总被引:1,自引:0,他引:1  
Previous studies using the technique of microinjection into brain nuclei indicated that the periaqueductal gray (PAG), nucleus accumbens, habenula and amygdala play an essential role in pain modulation and that these nuclei possibly act through a ‘mesolimbic neural loop‘ to exert an analgesic effect, in which Met-enkephalin (MEK) and β-endorphin (β-EP) have been implicated as the two major opioid peptides involved in antinociception. In the present study performed in rabbits, intracranial microinjection was supplemented with push-pull perfusion and radioimmunoassay to determine whether the release of enkephalins (ENK) and β-EP was increased in these nuclei when the putative neural circuit was activated by morphine administered into one of the nuclei. The results showed: (1) microinjection of morphine into the PAG increased the release of ENK and β-EP in the N. accumbens, and vice versa; (2) microinjection of morphine into the N. accumbens increased the release of ENK and β-EP in the amygdala, and vice versa; (3) morphine microinjected into the PAG caused an increase in the release of ENK and β-EP in the amygdala and vice versa, although the release of ENK in PAG was statistically not significant. These results indicate that PAG, N. accumbens and amygdala are connected in a network served by a positive feedback circuitry.  相似文献   
17.
Acetylcholinesterase inhibitors may improve myelin integrity.   总被引:2,自引:0,他引:2  
Recent clinical trials have revealed that cholinergic treatments are efficacious in a wide spectrum of neuropsychiatric disorders that span the entire human lifespan and include disorders without cholinergic deficits. Furthermore, some clinical and epidemiological data suggest that cholinergic treatments have disease modifying/preventive effects. It is proposed that these observations can be usefully understood in a myelin-centered model of the human brain. The model proposes that the human brain's extensive myelination is the central evolutionary change that defines our uniqueness as a species and our unique vulnerability to highly prevalent neuropsychiatric disorders. Within the framework of this model the clinical, biochemical, and epidemiologic data can be reinterpreted to suggest that nonsynaptic effects of cholinergic treatments on the process of myelination and myelin repair contributes to their mechanism of action and especially to their disease modifying/preventive effects. The ability to test the model in human populations with safe and noninvasive imaging technologies makes it possible to undertake novel clinical trial efforts directed at primary prevention of some of the most prevalent and devastating of human disorders.  相似文献   
18.
HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white matter hyperintensities. METHODS: In the Leukoaraiosis And DISability in the elderly (LADIS) study, we investigated the relationships between DM, hypertension, blood pressure and MTA in 582 subjects, stratified by white matter hyperintensity severity, using multinomial logistic regression. MTA was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95% CI: 1.1-7.8) compared with an MTA score of 0 (no atrophy). The odds ratio for MTA score 2 was not significantly increased (OR 1.8; CI: 0.9-4). Systolic and diastolic blood pressure and a history of hypertension were not associated with MTA. There was no interaction between DM and hypertension. Stratification on white matter hyperintensities (WMH) did not alter the associations. CONCLUSION: Our study strengthens the observation that MTA is associated with DM, independently of the amount of small vessel disease as reflected by WMH.  相似文献   
19.
Alzheimer's disease (AD) generally begins with mild memory problems which occur in an insidious manner and progresses to the development of multiple cognitive impairments. There is a ‘gray’ area between what is classified as ‘normal’ and what is classified as ‘dementia’, currently called mild cognitive impairment (MCI). In this article, a case of MCI is described, and the diagnosis, assessment, subclassification (pre‐Alzheimer type and white matter lesion type) and future therapeutic plans for MCI are reviewed.  相似文献   
20.
BACKGROUND: Consistent evidence has indicated that air pollution increases the risk of cardiovascular diseases. The underlying mechanisms linking air pollutants to increased cardiovascular risk are unclear. OBJECTIVES: We investigated the association between the pollution levels and changes in such global coagulation tests as the prothrombin time (PT) and the activated partial thromboplastin time (APTT) in 1218 normal subjects from the Lombardia Region, Italy. Plasma fibrinogen and naturally occurring anticoagulant proteins were also evaluated. METHODS: Hourly concentrations of particulate (PM10) and gaseous pollutants (CO, NO2, SO2, and O3) were obtained from 53 monitoring sites covering the study area. Generalized additive models were applied to compute standardized regression coefficients controlled for age, gender, body mass index, smoking, alcohol, hormone use, temperature, day of the year, and long-term trends. RESULTS: The PT became shorter with higher ambient air concentrations at the time of the study of PM10 (coefficient = -0.06; P < 0.05), CO (coefficient = -0.11; P < 0.001) and NO2 (coefficient =-0.06; P < 0.05). In the 30 days before blood sampling, the PT was also negatively associated with the average PM(10) (coefficient = -0.08; P < 0.05) and NO2 (coefficient = -0.08; P < 0.05). No association was found between the APTT and air pollutant levels. In addition, no consistent relations with air pollution were found for fibrinogen, antithrombin, protein C and protein S. CONCLUSIONS: This investigation shows that air pollution is associated with changes in the global coagulation function, suggesting a tendency towards hypercoagulability after short-term exposure to air pollution. Whether these changes contribute to trigger cardiovascular events remains to be established.  相似文献   
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