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11.
大鼠皮质神经元的体外培养和纯化 总被引:8,自引:2,他引:6
目的:探讨大鼠皮质神经元分离纯化的有效方法。方法:取胎鼠大脑皮质细胞,分别在不同的培养液中进行原代培养,利用相差显微镜对培养的细胞进行动态观察;并以免疫细胞化学技术对神经元进行染色。结果:在相差显微镜下可见加用N2添加剂和胎牛血清培养的神经元生长良好,胞体形态多样,突起数目多,长度长,与邻近神经元的胞体或突起形成接触,而胶质细胞则大量死亡,神经元纯化率达94%以上,未加用N2添加剂培养的神经元胶质细胞大量存在,神经元纯化率达50%左右。结论:N2添加剂和胎牛血清联合应用可使大鼠皮质神经元得到良好的生长和有效纯化。 相似文献
12.
T. L. Naneishvili M. G. Dashniani G. I. Machavariani 《Neuroscience and behavioral physiology》1987,17(1):49-55
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985. 相似文献
13.
Nonlinear sensory cortex response to simultaneous tactile stimuli in writer's cramp. 总被引:1,自引:0,他引:1
Terence D Sanger Alvaro Pascual-Leone Daniel Tarsy Gottfried Schlaug 《Movement disorders》2002,17(1):105-111
Writer's cramp is a task-specific dystonia that leads to involuntary hand postures during writing. Abnormalities of sensory processing may play a pathophysiological role in this disorder. Electrophysiology studies in a monkey model of focal dystonia have revealed de-differentiation of sensory maps and the existence of single cells in hand regions of area 3b with enlarged receptive fields that extend to the surfaces of more than one digit. These changes may lead to abnormal processing of simultaneous sensory inputs. To study abnormal processing of simultaneous sensory information in adult humans with writer's cramp, we used functional magnetic resonance imaging to compare the response in primary sensory cortex with simultaneous tactile stimulation of the index and middle finger, with the response to stimulation of each finger alone. We tested five patients with writer's cramp and seven unaffected (normal) subjects. In the normal subjects, a linear combination of the activation patterns for individual finger stimulation predicts the pattern of activity for combined stimulation with 12% error. In writer's cramp patients, the linear combination predicted the combined stimulation pattern with 30% error. Results indicate a nonlinear interaction between the sensory cortical response to individual finger stimulation in writer's cramp. This altered interaction may contribute to the motor abnormalities. 相似文献
14.
Francisco Jose Martinez-Guijarro Eduardo Soriano Jose Antonio del Rio Carlos Lopez-Garcia 《Brain research》1991,547(2)
An antibody against the calcium binding protein parvalbumin selectively labels a set of neurons in the cerebral cortex of lizards. Golgi-like immunostained bipolar, multipolar and pyramid-like neurons appear mainly located in the inner plexiform layers. Parvalbumin-immunoreactive (PARV-IR) puncta are concentrated in the cell layer of the dorsal and dorsomedial cortices showing a basket-like distribution. The morphology and distribution of PARV-IR neurons and puncta overlap GABA-immunostaining in the cerebral cortex of lizards. Thus, it is likely that PARV-IR neurons are a subset of the cortical GABAergic neurons of lizards. 相似文献
15.
目的利用血氧水平依赖性功能性磁共振成像(BOLD-fMR I)技术,探索人类近视性屈光参差是否对大脑皮层功能和结构造成影响。方法采用无磁MR I专用眼镜纠正屈光不正,以1.5T磁共振成像系统采集8例近视性屈光参差者枕叶视皮层兴趣区BOLD-fMR I数据,比较双眼皮层激活部位及范围的不同,及视力较差眼屈光纠正前后皮层激活情况的变化,分析其改变特点及机制。结果矫正屈光基础上,近视性屈光参差者双眼激活范围没有明显差异(P>0.05);视力较差眼屈光矫正前后皮层激活范围有明显差异(P<0.05)。结论人类近视性屈光参差可能没有发生明显的皮层功能损害及优势眼的转移;配镜可明显提高视力较差眼的皮层激活,应尽早配镜或手术矫正。 相似文献
16.
Israel Liberzon Stephan F Taylor K Luan Phan Jennifer C Britton Lorraine M Fig Joshua A Bueller Robert A Koeppe Jon-Kar Zubieta 《Neuropsychopharmacology》2007,61(9):1030-1038
BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD. 相似文献
17.
Genetic variation in serotonin transporter alters resting brain function in healthy individuals. 总被引:1,自引:0,他引:1
Hengyi Rao Seth J Gillihan Jiongjiong Wang Marc Korczykowski Geena Mary V Sankoorikal Kristin A Kaercher Edward S Brodkin John A Detre Martha J Farah 《Neuropsychopharmacology》2007,62(6):600-606
BACKGROUND: Perfusion functional magnetic resonance imaging (fMRI) was used to investigate the effect of genetic variation of the human serotonin transporter (5-HTT) gene (5-HTTLPR, SLC6A4) on resting brain function of healthy individuals. METHODS: Twenty-six healthy subjects, half homozygous for the 5-HTTLPR short allele (s/s group) and half homozygous for the long allele (l/l group), underwent perfusion functional and structural magnetic resonance imaging during a resting state. The two genotype groups had no psychiatric illness and were similar in age, gender, and personality scores. RESULTS: Compared with the l/l group, the s/s group showed significantly increased resting cerebral blood flow (CBF) in the amygdala and decreased CBF in the ventromedial prefrontal cortex. The effect of functional modulation in these regions by 5-HTTLPR genotype cannot be accounted for by variations in brain anatomy, personality, or self-reported mood. CONCLUSIONS: The 5-HTTLPR genotype alters resting brain function in emotion-related regions in healthy individuals, including the amygdala and ventromedial prefrontal cortex. Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression. 相似文献
18.
Ayman Agha Gabriel Glockzin Matthias Woenckhaus Wolfgang Dietmaier Igors Iesalnieks Hans J. Schlitt 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):671-677
Background Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with
an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore,
in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer.
Materials and methods The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma—8 patients with insular, 11 patients
with follicular, and 21 patients with papillary thyroid carcinomas—was compared. Disease-free survival and disease-specific
death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic
factors.
Results At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among
those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid
carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%).
Conclusion Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage
who have follicular or papillary thyroid carcinoma. 相似文献
19.
Understanding the mechanisms of food intake and obesity 总被引:2,自引:1,他引:1
E. T. Rolls 《Obesity reviews》2007,8(S1):67-72
20.
益气复智颗粒对多发脑梗死性痴呆模型大鼠脑组织细胞凋亡的影响 总被引:1,自引:0,他引:1
目的 观察益气复智颗粒对多发脑梗死性痴呆模型大鼠脑皮质形态学、细胞凋亡的影响。方法 采用颈内动脉注射血栓的方法,复制多发梗死性痴呆大鼠模型,观察益气复智颗粒12.42g/kg分别于手术前、手术前后、手术后灌胃对实验动物脑皮质形态学、细胞凋亡的影响。结果 益气复智颗粒能使脑缺血后脑内神经细胞凋亡数目下降。结论 益气复智颗粒具有较好的保护脑神经元,阻断脑缺血致神经细胞死亡病理过程的作用。 相似文献