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91.
Preclinical studies demonstrate that chronic stress modulates the effects of oestradiol (E2) on behaviour through the modification of the amygdala and the medial prefrontal cortex (mPFC) neuronal structure. Clinical studies suggest that alterations in amygdala functional connectivity (FC) with the mPFC may be associated with stress‐related phenotypes, including mood and anxiety disorders. Thus, identifying the effects of stress and E2 on amygdala‐mPFC circuits is critical for understanding the neurobiology underpinning the vulnerability to stress‐related disorders in women. In the present study, we used a well‐validated rhesus monkey model of chronic psychosocial stress (subordinate social rank) to examine effects of E2 on subordinate (SUB) (i.e. high stress) and dominant (DOM) (i.e. low stress) female resting‐state amygdala FC with the mPFC and with the whole‐brain. In the non‐E2 treatment control condition, SUB was associated with stronger left amygdala FC to subgenual cingulate (Brodmann area [BA] 25: BA25), a region implicated in several psychopathologies in people. In SUB females, E2 treatment strengthened right amygdala‐BA25 FC, induced a net positive amygdala‐visual cortex FC that was positively associated with frequency of submissive behaviours, and weakened positive amygdala‐para/hippocampus FC. Our findings show that subordinate social rank alters amygdala FC and the impact of E2 on amygdala FC with BA25 and with regions involved in visual processing and memory encoding.  相似文献   
92.
目的探讨老年高级别胶质瘤患者的临床特点和治疗方案。方法回顾性分析2012年4月至2017年8月中国医学科学院,北京协和医院神经外科连续收治的32例老年高级别胶质瘤患者的临床资料,总结其临床表现、术前Karnofsky功能状态评分(KPS)、合并症情况(查尔森合并症指数)、肿瘤病理学分型、治疗方法以及患者的总生存期。所有患者均行手术切除肿瘤或活组织检查术,术后辅以放化疗、单纯化疗或靶向治疗。采用Kaplan-Meier法探讨手术方式、合并症情况以及术前KPS对患者总生存期的影响。结果32例患者中,男21例,女11例;年龄为(71.9±6.9)岁(65~79岁);其中世界卫生组织(WHO)Ⅳ级(胶母细胞瘤)22例(68.7%),Ⅲ级10例(31.3%);术前中位KPS(范围)为78.1分(40~90分);中位查尔森合并症指数(范围)为5.7(4~8)。32例患者中,行病灶切除术21例(65.6%),行活组织检查术11例(34.4%)。术后行标准Stupp方案治疗7例,行替莫唑胺辅助化疗9例,行靶向治疗1例,未行进一步治疗11例。失访4例。32例患者的总生存期为1.2~73.3个月,中位值为15.8个月。生存分析结果表明,手术方式、术前KPS以及查尔森合并症指数并非患者总生存期的影响因素(均P>0.05)。结论老年高级别胶质瘤患者的一般情况较差,合并症多,通过采用手术、放化疗等综合治疗后生存期仍较短。在进行治疗方案的选择时,应根据患者的具体情况选择相对有利的治疗方案。  相似文献   
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95.
目的 基于静息态脑电图探索卒中后抑郁(post-stroke depression,PSD)脑网络特征异常改变,提取 客观生物标志物。 方法 回顾性分析深圳市人民医院脑电数据库中缺血性卒中慢性期患者病例资料,收集静息态 脑电图与汉密尔顿抑郁量表(Hamilton depression scale,HAMD)、MMSE及NIHSS评分资料。以HAMD评分 ≥20分为分界值,并通过病灶位置及体积匹配将患者分为PSD组和卒中后非抑郁(post stroke nondepression, PSND)组。脑电图数据预处理后,分别基于相干性虚部及能量包络在皮层源层面建立不同 频段功能连接矩阵,采用基于网络的统计方法分析两组间差异。 结果 与PSND组比较,PSD组患者①基于相干性虚部的脑网络连接在δ频段减弱,以顶叶脑区连接 减弱更明显;θ频段减弱,以左侧额顶颞枕、边缘叶及右侧额叶连接减弱更明显;γ频段增强,以左 侧额叶、边缘叶及右侧顶叶脑区连接增强更明显;②基于能量包络的脑网络连接在α频段增强,以双 侧顶枕叶脑区连接增强更明显。 结论 PSD患者脑网络发生异常改变,静息态脑电图是揭示这种改变的有效工具。  相似文献   
96.
Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis.  相似文献   
97.
BackgroundAim of this study was to assess the accuracy of ventricular septal defects (VSD) using high pitch computed tomography angiography (CTA) of the chest in children below 1 year of age, compared to the intraoperative findings and echocardiography.MethodsOut of 154 patients that underwent Dual-Source CTA of the chest using a high-pitch protocol at low tube voltages (70–80 kV), 55 underwent surgical repair of a VSD (median age 8 days, range 1–348 days). The margins of the VSDs and their relation to the surrounding structures were reproduced by en-face views using multiplanar reformations (MPR). Absolute diameter, normalized area and relative area compared to the aortic valve annulus were used for discrimination between restrictive and non-restrictive defects. Localization was classified into four subtypes. The results were compared to two-dimensional echocardiography and intraoperative findings.ResultsMedian absolute size of VSDs did not differ significantly between CTA-measurements (10.8 mm, range 2.8–18.1 mm) and intraoperative findings (12.0 mm, 3.0–25.0 mm, p = 0.09). Echocardiographic values were significantly lower (9.6 mm, 3.0–18.5 mm, both p < 0.01). The classification of the location and orientation matched the intraoperative situs in 96.4% of all cases using CT and in 87.3% using echocardiography. Echocardiography missed the relation to valves in 11% of all cases. Pre-interventional sensitivity and specificity for detection of a VSD were 97.2/98.9% compared to echocardiography. Median radiation dose was 0.32 mSv (range 0.12–2.00 mSv) and differed significantly between second and third generation Dual-Source CT (0.43 vs. 0.22 mSv, p = 0.003).ConclusionSize and subtype of VSDs can be accurately assessed by CTA of the chest in patients with complex congenital heart defects at a very low radiation dose.  相似文献   
98.
BackgroundSpasticity management in severely brain-injured patients with disorders of consciousness (DOC) is a major challenge because it leads to complications and severe pain that can seriously affect quality of life.ObjectivesWe aimed to determine the feasibility of a single session of transcranial direct current stimulations (tDCS) to reduce spasticity in chronic patients with DOC.MethodsWe enrolled 14 patients in this double-blind, sham-controlled randomized crossover pilot study. Two cathodes were placed over the left and right primary motor cortex and 2 anodes over the left and right prefrontal cortex. Hypertonia of the upper limbs and level of consciousness were assessed by the Modified Ashworth Scale (MAS) and the Coma Recovery Scale-Revised (CRS-R). Resting state electroencephalography was also performed.ResultsAt the group level, spasticity was reduced in only finger flexors. Four responders (29%) showed reduced hypertonicity in at least 2 joints after active but not sham stimulation. We found no behavioural changes by the CRS-R total score. At the group level, connectivity values in beta2 were higher with active versus sham stimulation. Relative power in the theta band and connectivity in the beta band were higher for responders than non-responders after the active stimulation.ConclusionThis pilot study highlights the potential benefit of using tDCS for reducing upper-limb hypertonia in patients with chronic DOC. Large-sample clinical trials are needed to optimize and validate the technique.  相似文献   
99.
高迁移率族蛋白A2(HMGA2)是一种非组蛋白,本身不具有转录活性,但它可通过与染色质结合改变其结构,继而调节其他基因的转录,从而促进肿瘤的侵袭和转移。相关RNA基因能够调控HMGA2在肿瘤中的作用,同时肿瘤的侵袭性与上皮间质转化密切相关,可以通过靶向HMGA2基因治疗相关肿瘤。文章主要介绍HMGA2与肿瘤之间关系的研究进展。  相似文献   
100.
This article is the first in a series of three, dedicated to the history and functions of what is known as a UMD in France: Unités pour Malades Difficiles, or “Units for Difficult Patients”. This particular article focuses on the oldest such secure structure, UMD Henri Colin, created in 1910 in Villejuif as a quartier de sûreté, or a “secure ward”. The article aims to detail evolutions in treatment and the types of patient treated over more than one hundred years, parallel to social change. Four distinct chronological periods are examined, for their perspective on professional practice as much as for the reasons given for patients’ admission and the psychopathological profiles of “dangerous” patients. Clinical vignettes are used to illustrate this historical evolution.  相似文献   
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