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81.
82.
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
83.
扩大的椎板间开窗治疗腰椎间盘突出伴侧隐窝狭窄(附140例报告) 总被引:1,自引:0,他引:1
本组采用的扩大的椎板开窗术治疗腰椎间盘突出合并侧隐窝狭窄140例。结果全部优良,与适应症严格选择和手术损伤小有关。强调切除卡压神经根的侧隐窝后壁外侧,即上关节突的冠状面.不失其脊椎三柱系统的三角结构。俯卧位头低足高,可减少硬膜囊张力避免负损伤。切除棘突下椎板时,用神经拉勾代替神经剥离器易于分离黄韧带,用90度的椎板咬骨钳斜向棘突方向,可满意地切除该部份椎板黄韧带,并可刮切椎板内层。神经根周围滴入醋酸炎舒松A2-3ml,术后疼痛锐减。减压窗口置盖明胶海绵有其争议,作者实践体会放置害处不大,要求病人有“护腰”意识。 相似文献
84.
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
85.
Shaping ability of the M4 handpiece and Safety Hedstrom Files in simulated root canals 总被引:1,自引:0,他引:1
A. LLOYD A. JAUNBERZINS A. DHOPATKAR S. BRYANT P. M. H. DUMMER 《International endodontic journal》1997,30(1):16-24
The aim of this study was to assess the shaping ability of the M4 reciprocating handpiece and Safety Hedstrom files in simulated canals. A total of 40 simulated canals of various angles and positions of curvature were prepared with an M4 handpiece using Safety Hedstrom files oriented with the ground, flattened surface towards the inner aspect of the curve. A standard regimen was adopted throughout. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount and location of resin material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Preparation time varied significantly (P<0.001) between the canal types; overall, 20° canals were prepared more quickly than 40° canals. Zips and elbows were observed in 16 out of the 40 canals with most (11) being created in 40° specimens. Ledges were found in 19 canals and perforations in only 1. There were no significant differences between canal shapes for these aberrations. Excessive removal of material from the inner aspect of the canal at the curve to create a danger zone was found in 20 canals, but only in those with 40° curves. Significant differences in total canal width between the canal types were seen at the zips (P<0.05), elbows (P<0.05) and danger zones (P<0.001). Transportation at the danger zones varied significantly (P<0.001) between canal types. Under the conditions of this study, the M4 handpiece and Safety Hedstrom files created hour-glass preparations in a substantial proportion of canals. In reality, the Safety Hedstrom file with its one flattened surface was ineffective at reducing removal of material along the inner aspect of canal curves in severely curved specimens and clearly has the potential to create strip perforations in teeth. 相似文献
86.
Peter R. McNally DO John C. Lemon MD John S. Goff MD Stephen R. Freeman MD 《Digestive diseases and sciences》1993,38(2):369-373
Summary A case of a 31-year-old female with congenital esophageal stenosis presenting with symptoms of chest pain caused by esophageal dysmotility is described. The involved segment in congenital esophageal stenosis has a characteristic thickening of the muscularis propria layer, as seen by EUS examination. In these patients, symptoms of dysphagia can be managed with esophageal dilation and noncardiac esophageal chest pain responds to pharmacotherapy with diltiazem.The opinions and assertions contained herein are the private ones of the authors and are not to be construed as official policy or reflecting the views of the Army or the Department of Defense. 相似文献
87.
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
88.
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
89.
90.
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