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71.
Morphological changes of the soleus motoneuron pool in chronic midthoracic contused rats 总被引:1,自引:0,他引:1
This study investigated the morphological features of the soleus motoneuron pool in rats with chronic (4 months), midthoracic (T8) contusions of moderate severity. Motoneurons were retrogradely labeled using unconjugated cholera toxin B (CTB) subunit solution injected directly into the soleus muscle of 10 contused and 6 age- and sex-matched, normal controls. Morphometric studies compared somal area, perimeter, diameter, dendritic length, and size distribution of labeled cells in normal and postcontusion animals. In normal animals, motoneurons with a mean of 110.4 +/- 5.2 were labeled on the toxin-injected side of the cord (left). By comparison, labeled cells with a mean of 93.0 +/- 8.4 (a 16% decrease, P = 0.006) were observed in the chronic spinal-injured animals. A significantly smaller frequency of very small (area, approximately 100 microm2) and medium (area, 545-914 microm2) neurons, and a significantly higher frequency of larger (area, >914 microm2) neurons was observed in the labeled soleus motoneuron pools of injured animals compared with the normal controls. Dendritic bundles in the contused animals were composed of thicker dendrites, were arranged in more closely aggregated bundles, and were organized in a longitudinal axis (rostrocaudal axis). Changes in soleus motoneuron dendritic morphology also included significant decrease of total number of dendrites, increased staining, hypertrophy of primary dendrites, and significant decreased primary, secondary, and tertiary branching. The changes in size distribution and dendritic morphology in the postcontusion animals possibly resulted from cell loss and transformation of medium cells to larger cells and/or injury-associated failure of medium cells to transport the immunolabel. 相似文献
72.
Walhovd KB Fjell AM Reinvang I Lundervold A Fischl B Salat D Quinn BT Makris N Dale AM 《Neuropsychologia》2005,43(5):704-713
The rationale for the present study was to investigate the relationship between cortical volume, the latency of the ERP component P3a (as a measure of speed-of-processing), and performance intelligence (not adjusted for age differences). Seventy-one participants aged 20-88 years underwent a visual 3-stimuli oddball ERP task, an MRI-scan, and intelligence testing. P3a latency and cortical volume shared 9% variance (p<.05) and both were significantly related to performance intelligence (R2=.26 and .40, respectively). The amount of explained variance increased significantly (to R2=.51) when both measures were used as simultaneous predictors. When a path diagram was constructed including age as an exogenous variable, P3a latency and cortical volume both significantly predicted performance intelligence, but were no longer related to one another. The main conclusion from the study is that speed and size are complementary in prediction of performance intelligence, and the theoretical implications are discussed. 相似文献
73.
Morphometric ultrastructural analysis of satellite cells in denervated rat soleus muscle 总被引:1,自引:0,他引:1
Morphometric analysis of the ultrastructural changes of satellite cells (SCs) of rat soleus muscle 7, 14, and 36 days post denervation was performed. Denervation caused decrease of surface area cross-section of SCs and their nuclei, volume fractions of nucleus and Golgi complex elements and ribosomes number. In contrast, the increase of surface area/volume ratio of SCs and nucleus, volume fraction and number of endosome/lysosome-like structures, and number of caveolae-like structures was noticed. Ultrastructural changes of SCs in denervated muscles strongly suggest decline of cell activity accompanied by increased processes of degradation of material of endo-, and/or egzogenous origin. 相似文献
74.
An ultrastructural and quantitative study of age-related changes in the capillaries of the dorsal lateral geniculate nucleus was carried out using male Wistar rats aged 3, 24, and 28 months. The most important structural changes were found in the basal lamina: thickenings either homogeneously distributed or in specific points; spurs towards the astrocyte sheath; and osmiophilic membrane-like inclusions located within the basal lamina. Endothelial cells and pericytes showed an increase in inclusions and dense bodies in the cytoplasm. The quantitative study showed that the most pronounced alteration was the thickening of the basal lamina, which existed at 24 months. Later, at 28 months, thinning of the endothelial cells was observed together with an increase in mitochondria size and the number of pinocytic vesicles. These changes could be an endothelial cell response to compensate for the increasing transport difficulties caused by the thickening of the basal lamina. The progressive age-related changes observed in the structure of the capillaries might have an effect on the regulation of blood and brain tissue exchanges, and thus might contribute to the development of degenerative alterations in surrounding aging neurones. 相似文献
75.
Morphometry of the anterior third ventricle region as a guide for the subfrontal (translaminaterminalis) approach 总被引:1,自引:0,他引:1
The anterior third ventricle region acquires clinical significance in benign and malignant tumors and cyst formations, of
which craniopharyngiomas and gliomas are the most common. The subfrontal approach is one of the most preferred approaches
for removing these tumors. In this study, the microsurgical anatomy of 81 Turkish, adult cadaveric hemispheres was examined
to provide morphometric data of the region. These measurements from the anterior third ventricle region serve as a guide for
neurosurgeons during surgical approach for removing anterior third ventricle tumors. 相似文献
76.
77.
Cullen TJ Walker MA Parkinson N Craven R Crow TJ Esiri MM Harrison PJ 《Schizophrenia Research》2003,60(2-3):157-166
Four studies have reported that the mediodorsal nucleus of the thalamus (MD) is smaller and contains fewer neurons in schizophrenia. The MD is a key node in a circuit proposed to be dysfunctional in the disorder. However, one study did not find a MD volume loss in schizophrenia, and all the studies to date are relatively small. Given the importance of establishing unequivocally the presence of MD pathology, we have carried out a study of the volume and number of neurons in the left and right MD in 21 patients with schizophrenia and 27 healthy comparison subjects. We also measured the size of MD neurons, and estimated total thalamic volume. We found no difference in the volume of the MD, the number of MD neurons, or the size of MD neurons in either hemisphere in schizophrenia. Neither was total thalamic volume altered. There are no obvious methodological or clinical factors to explain our failure to replicate the finding of MD involvement in schizophrenia. Hence our negative observations, in the largest sample yet investigated, cast doubt on the robustness and/or the generalisability of MD neuropathology in schizophrenia. 相似文献
78.
应用图像分析研究卵巢浆液性囊腺肿瘤形态学变化 总被引:2,自引:0,他引:2
目的:应用日本产Luzex-F型图像分析仪,对40例卵巢浆液性囊腺肿瘤与5例正常卵巢上皮组织进行了形态定量测定、比较分析,旨在探寻形态定量指标在鉴别诊断中的价值。方法:应用DNA特异染色(Feulgen染色),测量每例50 ̄70个细胞核的面积、周长、最大直径、等效圆直径、核形状因子5项参数。经统计学分析。结果:上述各参数在各组之间具有非常显著性差异(P〈0.01),交界性细胞核最大,恶性细胞核形状 相似文献
79.
One hundred and twenty-five small intestinal biopsies from children with coeliac disease (CD), cow's milk protein intolerance (CMPI) and controls were compared by morphometric analysis, by counting intraepithelial lymphocytes (IEL) and by quantitative evaluation of immunoglobulin-containing cells of lamina propria. The double-stain immunofluorescent technique of Brandtzaeg and Baklien [2] was used, based on defined mucosal tissue units. A patchy enteropathy was found in 60% of CMPI, and in 14% of nonspecific changes, but never in CD. There was a significant difference in crypt depth between CD (360±80 m) and CMPI (217±92 m), even when lesions of equal grade were compared (P<0.015). IEL counts per 1000 epithelial cells showed even better discrimination between the groups (CD: 793±173, CMPI: 320±143, P<0.001). In CD, there was a relatively greater increase of IgM-cells (x4.9) and of IgG-cells (x4.2) than of IgA-cells (x2.6). Ig-cell changes outlasted the morphological lesion in CD on a gluten-free diet. In CMPI, IgM-cells (x2.3), IgG-cells (x2.5), and IgA-cells (x1.7) were proportionately increased, compared to controls. A special increase of IgE-cells in CMPI could not be substantiated.By computerized stepwise discriminant analysis based upon crypt depth, villus/crypt-ratio, IEL-count, and counts of IgM-, IgG-, IgA-containing cells of lamina propria, accurate classification of patient groups was accomplished, even when only the initial biopsy data were analysed.Supported by Deutsche Forschungsgemeinschaft Gr 278/6 and Ste 305/1 相似文献
80.