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11.
Patients with temporomandibular disorder (TMD) perform poorly in neuropsychological tests of cognitive function. These deficits might be related to dysfunction in brain networks that support pain and cognition, due to the impact of chronic pain and its related emotional processes on cognitive ability. We therefore tested whether patients with TMD perform poorly in cognitive and emotion tasks and whether they had abnormal task-evoked brain activity. Seventeen female subjects with nontraumatic TMD and 17 age-matched healthy female subjects underwent functional magnetic resonance imaging while performing counting Stroop tasks comprising neutral words, incongruent numbers, or emotional words, including TMD-specific words. Group differences in task-related brain responses were assessed. Connectivity between 2 pairs of coupled brain regions during the cognitive and emotional tasks (prefrontal-cingulate and amygdala-cingulate) was also examined. The patients had sluggish Stroop reaction times for all Stroop tasks. Furthermore, compared to controls, patients showed increased task-evoked responses in brain areas implicated in attention (eg, lateral prefrontal, inferior parietal), emotional processes (eg, amygdala, pregenual anterior cingulate), motor planning and performance (eg, supplementary and primary motor areas), and activation of the default-mode network (medial prefrontal and posterior cingulate). The patients also exhibited decoupling of the normally correlated activity between the prefrontal and cingulate cortices and between the amygdala and cingulate cortex. These findings suggest that the slow behavioral responses in idiopathic TMD may be due to attenuated, slower, and/or unsynchronized recruitment of attention/cognition processing areas. These abnormalities may be due to the salience of chronic pain, which inherently requires attention.  相似文献   
12.
目的 分析黄柏、关黄柏粗皮及药材中盐酸小檗碱的分布情况.方法 采用HPLC法分别测定黄柏、关黄柏粗皮部分,去粗皮部分和原药材的盐酸小檗碱的含量,比较液相色谱图中色谱峰的差异.结果 盐酸小檗碱在粗皮中含量低,粗皮部位的色谱图与药材的色谱图不全相同.结论 粗皮成分应进一步分析,黄柏和关黄柏应严格按照药典的加工要求去除粗皮部位.  相似文献   
13.
Previous fMRI studies of sensorimotor activation in schizophrenia have found in some cases hypoactivity, no difference, or hyperactivity when comparing patients with controls; similar disagreement exists in studies of motor laterality. In this multi-site fMRI study of a sensorimotor task in individuals with chronic schizophrenia and matched healthy controls, subjects responded with a right-handed finger press to an irregularly flashing visual checker board. The analysis includes eighty-five subjects with schizophrenia diagnosed according to the DSM-IV criteria and eighty-six healthy volunteer subjects. Voxel-wise statistical parametric maps were generated for each subject and analyzed for group differences; the percent Blood Oxygenation Level Dependent (BOLD) signal changes were also calculated over predefined anatomical regions of the primary sensory, motor, and visual cortex. Both healthy controls and subjects with schizophrenia showed strongly lateralized activation in the precentral gyrus, inferior frontal gyrus, and inferior parietal lobule, and strong activations in the visual cortex. There were no significant differences between subjects with schizophrenia and controls in this multi-site fMRI study. Furthermore, there was no significant difference in laterality found between healthy controls and schizophrenic subjects. This study can serve as a baseline measurement of schizophrenic dysfunction in other cognitive processes.

Graphical Abstract

相似文献   
14.

Background:

Recent clinical and preclinical studies have suggested that deep brain stimulation (DBS) can be used as a tool to enhance cognitive functions. The aim of the present study was to investigate the impact of DBS at three separate targets in the Papez circuit, including the anterior nucleus of thalamus (ANT), the entorhinal cortex (EC), and the fornix (FX), on cognitive behaviors in an Alzheimer''s disease (AD) rat model.

Methods:

Forty-eight rats were subjected to an intrahippocampal injection of amyloid peptides 1-42 to induce an AD model. Rats were divided into six groups: DBS and sham DBS groups of ANT, EC, and FX. Spatial learning and memory were assessed by the Morris water maze (MWM). Recognition memory was investigated by the novel object recognition memory test (NORM). Locomotor and anxiety-related behaviors were detected by the open field test (OF). By using two-way analysis of variance (ANOVA), behavior differences between the six groups were analyzed.

Results:

In the MWM, the ANT, EC, and FX DBS groups performed differently in terms of the time spent in the platform zone (F(2,23) = 6.04, P < 0.01), the frequency of platform crossing (F(2,23) = 11.53, P < 0.001), and the percent time spent within the platform quadrant (F(2,23) = 6.29, P < 0.01). In the NORM, the EC and FX DBS groups spent more time with the novel object, although the ANT DBS group did not (F(2,23) = 10.03, P < 0.001). In the OF, all of the groups showed a similar total distance moved (F(1,42) = 1.14, P = 0.29) and relative time spent in the center (F(2,42) = 0.56, P = 0.58).

Conclusions:

Our results demonstrated that DBS of the EC and FX facilitated hippocampus-dependent spatial memory more prominently than ANT DBS. In addition, hippocampus-independent recognition memory was enhanced by EC and FX DBS. None of the targets showed side-effects of anxiety or locomotor behaviors.  相似文献   
15.
通过市场调查和文献研究,了解厚朴药材商品状况;同时采集样品进行分析,结合生产实际,制定新的厚朴商品规格等级标准。现行的规格等级标准中,将厚朴药材按来源划分为温朴与川朴2个品别,再按取皮部位划分为4种规格,每一种规格又按长度和质量划分若干等级;判断厚朴药材质量优劣的依据主要是性状特征(外观质量)。在新制定的厚朴商品标准中,等级的划分则是以厚度、厚朴酚与和厚朴酚含量为依据,即综合外观性状与药效成分(内在品质),科学评价药材质量。由于温朴与川朴的商品性状特征基本一致,外观难以区分,不再划分品别;又因蔸朴与耳朴部位重叠,规格简化为筒朴(含枝朴)、根朴、蔸朴等3种;其中,筒朴分为3个等级,根朴、蔸朴不分等(统货)。  相似文献   
16.
目的:建立黄柏生品、酒炙品和盐炙品的HPLC指纹图谱,比较不同产地黄柏及其炮制品指纹特征的差异。方法:采用HPLC比较10批黄柏生品、酒炙品和盐炙品的指纹图谱,流动相乙腈(A)-水(含0.3%磷酸和0.3%二乙胺,B)梯度洗脱(0~10 min,10%~14%A;10~20 min,14%~25%A;20~45 min,25%A;45~50 min,25%~65%A;50~55 min,65%~70%A;55~60 min,70%~75%A;60~70 min,75%~100%A),流速0.8 m L·min-1,柱温40℃,检测波长284 nm,分析时间70 min。结果:酒黄柏、盐黄柏与生黄柏的指纹图谱基本一致,但各成分间的相对含量存在差异,对其中的绿原酸、黄柏碱、木兰花碱、药根碱、小檗红碱、盐酸巴马汀、盐酸小檗碱、黄柏内酯进行了归属。10批黄柏生品、酒炙品和盐炙品共有模式色谱峰相似度均0.9。结论:建立的指纹图谱具有很好的精密度、重复性和稳定性,可作为黄柏及其炮制品质量评价的依据。  相似文献   
17.
【目的】基于像素的形态学测量(VBM )法分析颞叶癫痫患者脑区灰质密度和体积的差异,探讨VBM对常规M RI未发现病灶的颞叶癫痫患者的检测准确性。【方法】选择本院收治的30例常规M RI未发现病灶的颞叶癫痫患者(颞叶癫痫组),其中男13例,女17例;选择同期本院体检健康者30例(对照组),其中男16例,女14例。采用磁化预备快速梯度回波序列进行高分辨率全脑结构像扫描两组研究对象脑部,通过VBM分析其全脑灰质体积及密度变化。【结果】①颞叶癫痫患者组的左侧枕叶、楔叶,右侧小脑山顶脑区的灰质密度较对照组降低,差异有显著性意义;双侧壳核、外侧苍白球、左侧颞下回、右侧额下回脑区的灰质密度较对照组升高,差异有显著性意义;②颞叶癫痫患者组双侧岛叶,右侧中央前回、颞上回、楔叶、楔前叶、枕中回、缘上回,左侧颞中回、角回、舌回、颞横回、中央后回、中央旁小叶、海马旁回、梭状回的脑灰质体积较正常对照组降低,差异有显著性;未发现灰质体积升高的脑区。【结论】颞叶癫痫患者不仅颞叶灰质存在异常,而且颞叶外脑区也存在广泛的灰质异常,对于常规M RI未发现病灶的颞叶癫痫患者,进行VBM 分析可发现广泛的脑结构异常。  相似文献   
18.
目的:探讨桑白皮的潜在功能。方法:通过考察桑白皮在古代本草文献、古代含桑白皮方剂和《中华人民共和国药典》(简称《中国药典》) 2010版一部收载和显示的功用,以及现今药效学研究与临床经验,比较分析桑白皮业已失传的潜在功能。结果:确认古本草中记载桑白皮的核心功用和古代方剂配伍应用,与《中国药典》记录基本一致。而由本草文献总结出来的补虚益气、活血化瘀、生津止渴、化痰、止血、通淋、止痛、祛风、驱虫等潜在功能,以及《普济方》数据库中含桑白皮复方所治虚劳、疮疡痈疽、伤寒、跌打损伤、中风、消渴、淋泌、痹病、痰饮、出血、诸痛、寄生虫病、毒虫咬伤、风瘙痒、痘疹等病症,并未被《中国药典》收录。结论:结合实验研究和当今临床应用,可以确认补虚益气、活血化瘀、生津止渴、祛痰、止痛是桑白皮的潜在功用。  相似文献   
19.
目的:为了探究采用黄连附子汤治疗后的十二指肠溃疡患者的临床效果。方法:选取2014年12月—2015年4月来我院治疗的十二指肠溃疡患者40例,为该实验的探究对象,将患者进行分组,用随机数字方法,将患者分为观察组与对照组,每组设为20例,对照组采用枸檬酸铋钾与阿莫西林和奥美拉唑一起口服,而观察组患者则口服自制的黄连附子汤,经治疗后,观察和比较两组患者治疗后的溃疡愈合率与腹部疼痛消失率。结果:观察组患者在服用黄连附子汤后的溃疡愈合率与腹部疼痛消失率明显低于对照组患者的,两组比较具有统计学意义,(P0.05)。结论:观察组患者在该院服用黄连子附子汤后,大大地提高了患者十二指肠溃疡的康复程度,提高了溃疡愈合程度,减轻了患者腹部的疼痛感,对于康复过程是有明显效果的,值得医疗界引进及推广使用该治疗手段。  相似文献   
20.
《Medical image analysis》2015,19(8):1349-1360
Current neuroimaging investigation of the white matter typically focuses on measurements derived from diffusion tensor imaging, such as fractional anisotropy (FA). In contrast, imaging studies of the gray matter oftentimes focus on morphological features such as cortical thickness, folding and surface curvature. As a result, it is not clear how to combine findings from these two types of approaches in order to obtain a consistent picture of morphological changes in both gray and white matter.In this paper, we propose a joint investigation of gray and white matter morphology by combining geometrical information from white and the gray matter. To achieve this, we first introduce a novel method for computing multi-scale white matter tract geometry. Its formulation is based on the differential geometry of curve sets and is easily incorporated into a continuous scale-space framework.We then incorporate this method into a novel framework for “fusing” white and gray matter geometrical information. Given a set of fiber tracts originating in a particular cortical region, the key idea is to compute two scalar fields that represent geometrical characteristics of the white matter and of the surface of the cortical region. A quantitative marker is created by combining the distributions of these scalar values using Mutual Information. This marker can be then used in the study of normal and pathological brain structure and development. We apply this framework to a study on autism spectrum disorder in children. Our preliminary results support the view that autism may be characterized by early brain overgrowth, followed by reduced or arrested growth (Courchesne, 2004).  相似文献   
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