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21.
Aims: Extra-adrenal paragliomas are neoplasms which have been the subject of much debate regarding parameters to establish their biological behaviour. This study describes the clinicopathological and immunohistochemical features of 30 cases of spinal paragliomas. Methods and results: There were 15 male and 15 female patients. The median age at diagnosis was 46 years (range 20–74 years). Fourteen patients presented with back pain, two with numbness of the lower extremities, one with difficulty in walking and one with spinal cord compression. Nineteen tumours were located in the lumbar region, six in the cauda equina, two in the filum terminale, two in the thoracic region and one in the cervical region. All patients underwent gross total excision. The size of the tumours ranged from 10 to 50 mm. Histologically, 18 neoplasms showed alveolar (Zellballen) pattern, seven a spindle component, two eosinophilic granular cells suggestive of oncocytic metaplasia, two melanin pigment and one ganglion cells. Positive immunohistochemical results include: neuron-specific enolase 23/23 (100%), synaptophysin 21/23 (91%), S100 protein 22/23 (95%, sustentacular cells), leu-enkephalin 11/23 (47%), somatostatin 8/23 (34%), focal glial fibrillary acidic protein 7/23 (30%), focal keratin 5/23 (21%), neurofilament proteins 3/23 (13%) and adrenocorticotrophic hormine (ACTH) 1/23 (4%). Follow-up information obtained in 20 patients show 17 patients alive over a period of 6–216 months. One patient had bone metastases. Two patients died of unrelated causes, including one of congestive heart failure and one of myocardial infarction. Conclusions: In our experience, spinal paragangliomas behave as slow-growing tumours susceptible to potential cure by total excision. We agree with the current World Health Organization (WHO) classification as grade I tumours. Less than 1% may be locally aggressive. Spinal paragangliomas immunoreact not only for conventional neuroendocrine markers but also for peptides including somatostatin and ACTH and focally for the epithelial marker keratin.  相似文献   
22.
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   
23.
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   
24.
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   
25.
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   
26.
Although relatively high CO2 laser energies have been shown to sterilize root canals, the response of several bacterial strains to decreasing exposures of CO2 laser energy remains unknown. Freshly grown bacterial cells were irradiated on glass microscope coverslips. A comparison of equivalent energy exposures with differing parameters was made on the bacterial viability. No statistically significant difference was found in the energy required to kill closely related bacterial species. However, the energy density required to kill greater than 99.5% of the bacteria is less than 200 J/cm2, much less than that shown to sterilize in a previous study.  相似文献   
27.
本文通过200例成人颅颈静脉窝的观察与测量,对颈静脉窝的形态、位置及其与颅后窝、面神经管垂直部、鼓环的局部解剖关系进行研究,为临床应用及体质调查提供资料。  相似文献   
28.
脊髓手术中体感诱发电位监测的临床研究   总被引:3,自引:0,他引:3  
报告30例脊髓手术中体感诱发电位(SEP)连续监测的临床研究结果。SEP记录包括脊髓SEP(SSEP)和皮层SEP(SCEP)。麻醉药物对SEP有一定程度影响,SCEP相对较大。认为,至少术中SEP潜伏期延长不超过8%和波幅降低不超过50%,不会引起术后并发症,超过该范围由于病例较少,尚不能肯定与预后的关系,需进一步探讨。  相似文献   
29.
后天性外耳道狭窄的手术治疗   总被引:1,自引:0,他引:1  
目的探讨后天性外耳道狭窄的手术治疗方法及效果。方法对26例(27耳)外耳道狭窄行外耳道成形术或厢乳突根治鼓室成型术,取大腿内侧自体游离中厚皮片植皮,碘仿纱条压迫并扩张耳道。结果26例病人27耳随访6个月至8年,24耳外耳道宽敞,无再狭窄;3耳出现轻度狭窄,发生率11.1%(3/27),效果满意。结论对后天性外耳道狭窄的治疗可根据狭窄的原因、部位及程度等不同情况采用外耳道成形、游离中厚皮片移植或同时进行乳突根治鼓室成型术等手术治疗,术后局部换药,即能取得较好效果。  相似文献   
30.
显微内窥镜下治疗腰椎间盘突出症和腰椎管狭窄症   总被引:1,自引:1,他引:0  
目的探讨显微内窥镜(MED)治疗腰椎间盘突出症和腰椎管狭窄症的临床效果。方法MED下切除增生内聚的关节突、肥厚的黄韧带及突出的椎间盘,彻底解除对硬膜、神经根的压迫。结果随访324例,按中华骨科学脊柱学组腰背痛手术评定标准,优297例,良14例,差13例,疗效优良率达96.0%,结论MED损伤小、恢复快、疗效好。  相似文献   
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