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51.
Elemental composition and water content of myelinated axons and glial cells in rat central nervous system 总被引:1,自引:0,他引:1
The distribution of elements (e.g. Na, Cl, K) and water in CNS cells is unknown. Therefore, electron probe X-ray microanalysis (EPMA) was used to measure water content and concentrations (mmol/kg dry or wet weight) of Na, Mg, P, S, Cl, K and Ca in morphological compartments of myelinated axons and glial cells from rat optic nerve and cervical spinal cord white matter. Axons in both CNS regions exhibited similar water content ( 90%), and relatively high concentrations (wet and dry weight) of K with low Na and Ca levels. The K content of axons was related to diameter, i.e. small axons in spinal cord and optic nerve had significantly less (25–50%) K than larger diameter axons from the same CNS region. The elemental composition of spinal cord mitochondria was similar to corresponding axoplasm, whereas the water content (75%) of these organelles was substantially lower than that of axoplasm. In glial cell cytoplasm of both CNS areas, P and K (wet and dry weight) were the most abundant elements and water content was approximately 75%. CNS myelin had predominantly high P levels and the lowest water content (33–55%) of any compartment measured. The results of this study demonstrate that each morphological compartment of CNS axons and glia exhibits a characteristic elemental composition and water content which might be related to the structure and function of that neuronal region. 相似文献
52.
53.
本文报告了4例涉及椎体及其后部结构的全椎骨肿瘤的外科治疗,介绍了全椎骨切除术的手术方法及手术注意事项。手术采用后路附件切除,上下椎体Steffee钢板内固定,前路椎体切除自体髂骨植骨融合,初步效果满意。本手术难度大、出血多、危险性高,术中采用控制性低血压,以减少出血。 相似文献
54.
Z. Lackovi M. Jakup
evi A. Bunarevi I. Damjanov M. Relja I. Kostovi 《Brain research》1988,443(1-2):199-203
The content of serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and norepinephrine (NE) was analysed in 71 human spinal cords obtained post-mortem. The highest content of 5-HT, 5-HIAA and NE was found in the lumbar enlargement of the spinal cord. 5-HT and 5-HIAA content increased from fetal to adult spinal cord whereas the content of NE decreased. Characteristic segmental distribution of measured monoamines was present in adult spinal cord only. In two patients spinal cord lesion led to the reduction in spinal cord content of 5-HT, 5-HIAA and NE and loss of characteristic segmental distribution of these substances. These results are in general agreement with observations on spinal cord of different animal species. 相似文献
55.
颈脊髓压迫模型的建立及意义 总被引:1,自引:0,他引:1
目的 :旨在探索、建立颈脊髓压迫损伤的动物模型 ,并观察、研究其病理学改变过程 ,为临床治疗颈脊髓损伤提供理论依据。 方法 :通过在犬C4 、C5椎间孔置入不锈钢螺钉压迫脊髓 ,成功建立起一种新型不完全性颈脊髓压迫损伤的动物模型 ,并通过光镜和电镜研究创伤后不同时间脊髓的病理改变。 结果 :损伤后动物表现为不完全性瘫痪 ,随时间的推移运动功能逐渐恢复。病理改变结果可分三期 :早期脊髓内出血、水肿及神经元和神经纤维变性 ;中期神经元和神经纤维变性达到高峰 ,胶质细胞增生 ;晚期出现机化和修复 ,部分神经元和神经纤维恢复正常形态。 结论 :颈脊髓不完全性压迫损伤后脊髓功能有恢复的可能 ,临床应进行早期治疗。 相似文献
56.
A. Rimmelin P. L. Clouet S. Salatino P. Kehrli D. Maitrot M. Stephan J. L. Dietemann 《Neuroradiology》1997,39(3):203-206
Extradural arachnoid cysts are uncommon expanding lesions in the spinal canal which may communicate with the subarachnoid
space. Usually in the lower thoracic spine, they may cause symptoms by compressing the spinal cord or nerve roots. We report
cases of thoracic and lumbar arachnoid cysts studied by cystography, myelography, CT and MRI. These techniques showed extradural
cystic lesions containing cerebrospinal fluid, with variable communication with the subarachnoid space, causing anterior displacement
and flattening of the spinal cord.
Received: 3 November 1995 Accepted: 16 April 1996 相似文献
57.
58.
狗脊髓截除自体隐神经大网膜移植的初步观察 总被引:3,自引:0,他引:3
实验用6只狗于T13处切除脊髓8mm,局部用隐神经、大网膜移植。对照组6只狗单纯切除脊髓8mm。术后3个月、6个月实验组动物全部恢复到C/Ⅲ级功能,组织学切片见移植神经有不同程度存活,可记录到股四头肌、胫前肌电位。对照组动物仅达到0/0~A/I织功能,组织学切片见脊髓缺损处为结缔组织,诱电位波形消失。分析了影响脊髓神经功能恢复的原因。 相似文献
59.
胸腰椎稳定性重建方法的改进 总被引:2,自引:2,他引:0
为了改进胸腰椎脱位的治疗方法,更好地重建脊柱稳定性,设计了一种新的脊柱固定器械,由滚花钉及连接板构成,并通过椎弓根进行的一种脊柱后路短节段固定方法,脊柱固定范围限制在两个椎体间。1989年~1995年,临床应用这种新器械矫正胸腰椎脱位12例,经1~4年随访,畸形矫正满意,固定牢固。结果表明:该器械具有手术方法简单、固定牢固和手术创伤小等优点。认为,该项技术适用于胸腰椎稳定性的重建。 相似文献
60.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization. 相似文献