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71.
脑缺血大鼠海马超微结构的形态定量研究 总被引:4,自引:0,他引:4
对大鼠双侧颈总动脉夹闭2小时,经透射电镜观察海马,用Weibel氏形态定量法分别测量了海马1区和3区的线粒体和突触的表面积密度(Svi)、表面积—体积比(Si/Vi),并与对照组进行了比较。结果表明:缺血时海马1区受损较严重,表现为线粒体体积缩小,数量减少,Svi下降;突触数量有增多的趋势,但突触的Svi与Si/Vi变化不明显。缺血组海马3区受损较轻,线粒体和突触的结构基本正常,其Svi、Si/Vi与对照组差别不显著,提示了3区对缺血有较强的耐受性。 相似文献
72.
本文对296例小儿热性惊厥脑电图进行分析。结果:小儿热性惊厥脑电图(EEG)异常率48.65%,主要以阵性高幅慢波为主(77.78%)。小儿癫痫脑电图异常率(89.61%)。主要以阵发性棘慢波和局灶性改变为主(62.78%)。二周后EEG复查热性惊厥EEG大部分恢复正常(83.35%)。而小儿癫痫EEG未有恢复正常的。热性惊厥发作次数愈多,发作持续时间愈长EEG改变愈明显,二周后脑电图恢复正常的愈少。这对小儿热性惊厥的诊断和预后判定有重要价值。 相似文献
73.
74.
Xiao Liu Xiaohong Meng Lizhu Yang Yanling Long Yu Fujinami‐Yokokawa Jiayun Ren Toshihide Kurihara Kazuo Tsubota Kazushige Tsunoda Kaoru Fujinami Shiying Li East Asia Inherited Retinal Disease Society Study Group 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(3):694-707
Stargardt disease 1 (STGD1) is the most prevalent retinal dystrophy caused by pathogenic biallelic ABCA4 variants. Forty‐two unrelated patients mostly originating from Western China were recruited. Comprehensive ophthalmological examinations, including visual acuity measurements (subjective function), fundus autofluorescence (retinal imaging), and full‐field electroretinography (objective function), were performed. Next‐generation sequencing (target/whole exome) and direct sequencing were conducted. Genotype grouping was performed based on the presence of deleterious variants. The median age of onset/age was 10.0 (5–52)/29.5 (12–72) years, and the median visual acuity in the right/left eye was 1.30 (0.15–2.28)/1.30 (0.15–2.28) in the logarithm of the minimum angle of resolution unit. Ten patients (10/38, 27.0%) showed confined macular dysfunction, and 27 (27/37, 73.7%) had generalized retinal dysfunction. Fifty‐eight pathogenic/likely pathogenic ABCA4 variants, including 14 novel variants, were identified. Eight patients (8/35, 22.8%) harbored multiple deleterious variants, and 17 (17/35, 48.6%) had a single deleterious variant. Significant associations were revealed between subjective functional, retinal imaging, and objective functional groups, identifying a significant genotype–phenotype association. This study illustrates a large phenotypic/genotypic spectrum in a large well‐characterized STGD1 cohort. A distinct genetic background of the Chinese population from the Caucasian population was identified; meanwhile, a genotype–phenotype association was similarly represented. 相似文献
75.
Yamamoto N Yang M Jiang P Xu M Tsuchiya H Tomita K Moossa AR Hoffman RM 《Clinical & experimental metastasis》2003,20(7):633-638
We have established stable, bright green fluorescent protein (GFP)- or red fluorescent protein (RFP)-expressing HT-1080 human
fibrosarcoma clones. These cell lines showed similar cell proliferation rates and high-frequency experimental lung metastasis.
The HT-1080-GFP and -RFP clones enable simultaneous real-time dual-color imaging in the live animal. HT-1080 cells were transduced
with retroviral vectors containing GFP or RFP and the neomycin resistance gene. Stable transformants were selected stepwise
with G418 up to 800 μl/ml. Subsequently, high GFP- or RFP-expressing clones, HT-1080-GFP or HT-1080-RFP, respectively, were
selected. 3×106 cells from each clone were mixed and injected into the tail vein of SCID mice. The cells seeded the lung at high frequency
with subsequent formation of pure green and pure red colonies as well as mixed yellow colonies with different patterns visualized
directly on excised lungs. The lung metastases were also visualized by external fluorescence imaging in live animals through
skin-flap windows over the chest wall. Lung metastases were observed on the lung surface of all mice. SCID mice well tolerated
multiple surgical procedures for direct-view imaging via skin-flap windows. Real-time metastatic growth of the two different
colored clones in the same lung was externally imaged with resolution and quantification of green, red, or yellow colonies
in live animals. The color coding enabled determination of whether the colonies grew clonally or were seeded as a mixture
with one cell type eventually dominating, or whether the colonies grew as a mixture. The simultaneous real-time dual-color
imaging of metastatic colonies described in this report gives rise to the possibility of color-coded imaging of clones of
cancer cells carrying various forms of gene of interest.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
76.
Morphological and functional plasticity of olfactory ensheathing cells 总被引:12,自引:0,他引:12
In the primary olfactory pathway, olfactory ensheathing cells (OECs) extend processes to envelop bundles of olfactory axons
as they course towards their termination in the olfactory bulb. The expression of growth-promoting adhesion and extracellular
matrix molecules by OECs, and their spatially close association with olfactory axons are consistent with OECs being involved
in promoting and guiding olfactory axon growth. Because of this, OECs have been employed as a possible tool for inducing axonal
regeneration in the injured adult CNS, resulting in significant functional recovery in some animal models and promising outcomes
from early clinical applications. However, fundamental aspects of OEC biology remain unclear. This brief review discusses
some of the experimental data that have resulted in conflicting views with regard to the identity of OECs. We present here
recent findings which support the notion of OECs as a single but malleable phenotype which demonstrate extensive morphological
and functional plasticity depending on the environmental stimuli. The review includes a discussion of the normal functional
role of OECs in the developing primary olfactory pathway as well as their interaction with regenerating axons and reactive
astrocytes in the novel environment of the injured CNS. The use of OECs to induce repair in the injured nervous system reflects
the functional plasticity of these cells. Finally, we will explore the possibility that recent microarray data could point
to OECs assuming an innate immune function or playing a role in modulating neuroinflammation. 相似文献
77.
研究了磺化聚醚砜吸附柱对血浆中亚甲蓝的吸附效果,并检测了流经吸附柱的牛血清白蛋白随时间变化的规律以及过柱前后血浆中主要生化指标的变化情况.结果:磺化聚醚砜对亚甲蓝的吸附效果明显优于聚醚砜对亚甲蓝的吸附效果;其对白蛋白的吸附较小;对血浆中主要生化指标的影响可以忽略不计. 相似文献
78.
Kushiro K Zakir M Sato H Ono S Ogawa Y Meng H Zhang X Uchino Y 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,131(4):406-415
Saccular and utricular organs are essential for postural stability and gaze control. Although saccular and utricular inputs are known to terminate on vestibular neurons, few previous studies have precisely elucidated the origin of these inputs. We investigated the saccular and utricular inputs to single vestibular neurons in whole vestibular nuclei of decerebrated cats. Postsynaptic potentials were recorded from vestibular neurons after electrical stimulation of the saccular and utricular nerves. Ascending and descending axonal projections were examined by stimulating the oculomotor/trochlear nuclei and the cervical segment of the spinal cord, respectively. After each experiment, locations of recorded neurons were identified. The recorded neurons (140) were classified into vestibulo-spinal (79), vestibulo-oculo-spinal (9), and vestibulo-ocular (3) neurons based on antidromic responses; 49 other vestibular neurons were unidentified. The majority of recorded neurons were mainly located in the lateral vestibular nucleus. Most of the otolith-activated vestibular nuclei neurons seemed to participate in vestibulospinal reflexes. Of the total 140 neurons recorded, approximately one third (51) received saccular and utricular inputs (convergent neurons). The properties of these 51 convergent neurons were further investigated. Most (33/51) received excitatory postsynaptic potentials (EPSPs) after saccular and utricular nerve stimulation. These results implied that most of the convergent neurons in this study additively coded mixed information for vertical and horizontal linear acceleration. Based on the latencies of convergent neurons, we found that an early integration process for vertical and horizontal linear acceleration existed at the second-order level. 相似文献
79.
80.
CT三维重建在侧颅底的应用研究 总被引:6,自引:0,他引:6
目的 探讨CT三维重建在侧颅底的应用价值。方法 15例健康成人在Picker5000全身CT机上行连续轴位扫描,将扫描获得的原始数据输入Voxel Q图像后处理工作站,采用表面阴影法(surface shaded display,SSD)进行三维重建。结果 侧颅底CT三维重建能清楚显示正常侧颅底孔、裂和重要的骨性标志。重建的结构可整体显示或切割后单独显示,两均可在三维空间绕任意轴旋转任意角度。结论 三维CT能立体而直观的显示侧颅底骨性结构,有利于侧颅底外科手术方案的设计。 相似文献