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11.
正枕骨、寰椎和枢椎共同构成了枕颈部活动的结构功能单位,即枕颈交界区~([1-2])。炎症、创伤、肿瘤及畸形等因素会导致枕颈交界区失稳,从而引起颈脊髓或神经根的损伤、麻痹及难以忍受的疼痛,甚至危及生命~([3-4])。后路内固定融合技术是治疗枕颈部失稳的重要手段,目前常用术式为枕骨螺钉技术,该技术较钢丝固定技术有更好的生物力学稳定  相似文献   
12.
Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat.  相似文献   
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14.
脊髓损伤大鼠的阴茎海绵体肌电图研究   总被引:2,自引:0,他引:2  
目的探讨海绵体肌电图诊断脊髓性勃起功能障碍的价值。方法将24只成年雄性SD大鼠(300~400 g)分成:对照组、T9和L6损伤组(每组8只)。损伤脊髓1周后,用肌电图仪采集注射阿朴吗啡前后阴茎肌电数据,采集频率20~3 000 Hz、扫描速度5 ms/d、灵敏度10 μV/d。用t检验方法分析统计数据。结果对照组使用阿朴吗啡10 min均方根振幅为(5.60±0.89)μV, 大于T9损伤组(3.60±1.14)μV(P<0.05);使用阿朴吗啡前、使用后5 min和10 min高/低功率比均为0.05±0.03,小于L6损伤组0.13±0.04、0.15±0.07、0.13±0.07(P<0.05)。T9损伤组使用阿朴吗啡后5 min和10 min平均频率分别为(122.40±47.99)、(151.80±76.42)Hz,较L6损伤组(278.83±118.66)、(265.00±81.35)Hz低(P<0.05)。结论海绵体肌电图对脊髓性勃起功能障碍有诊断价值。  相似文献   
15.
后路椎体间融合术后融合器脱出的原因及其翻修术   总被引:3,自引:0,他引:3  
目的:探讨后路椎体间融合术后融合器脱出的原因及其翻修方法。方法:10例后路椎体间融合术后融合器脱出行翻修术的病例,其中腰椎滑脱症5例,腰椎管狭窄症3例,腰椎间盘突出症2例。手术节段为L4/54例,L5/S1 3例,L4/5+L5/S1 3例;融合器应用BAK(旋入型)7例,聚醚醚酮矩形融合器(PEEK)2例,钛金属矩形融合器1例。于首次术后1~90d内行翻修术。就其脱出原因,再次手术方法及疗效进行分析。结果:融合器脱出的原因:矩形融合器中2例型号太小,1例放置位置偏后;旋入型融合器1例定位错误,其余大都因两枚融合器之间发生碰撞挤压所致。翻修术后获得完整随访资料者8例,随访时间10-36个月,平均17个月,均得到融合,无融合器再次移位或脱出以及内同定的断裂,1例伴有足下垂者遗留患足背伸肌力减弱,其余病例神经症状消除。结论:后路腰椎椎体间融合术后融合器脱出的可能原因有融合器型号偏小导致椎间隙撑开不够,放置位置偏后,两枚融合器不对称或距离太近发生碰撞等。早期、积极的手术翻修能取得较好的疗效。  相似文献   
16.
Several studies have demonstrated that a descending dopaminergic pathway innervates the dorsal and the intermediate gray matter of the spinal cord and have suggested that this pathway is involved in pain modulation and in the control of autonomie functions. Other studies have also demonstrated the presence of dopamine (DA) and DA metabolites as well as of DA receptors in the ventral cord. There is also evidence for the implication of DA in the control of motor functions at the spinal level. The occurrence of a dopaminergic innervation in the ventral horn has been, however, disputed until recently. But recent work has demonstrated that the motoneural cell groups in the ventral horn (lamina IX) are a target for descending dopaminergic fibers. In addition, the possibility that DA is a mediator of primary afferent fibers has also been postulated. Finally, the occurrence of dopaminergic cell bodies has been suggested in the spinal cord. This indicates that DA is probably implicated in a complex manner in spinal functions. In the present paper the possible involvement of DA in sensory and in motor functions at spinal level will be discussed in view of neurochemical observations made in polyarthritic rats, in which pain-related behavior and reduction of locomotor activity associated with a marked decrease in mobility, are observed.  相似文献   
17.
Summary Two contrasting cases of cervical intramedullary cavernous angioma in young female patients are reported. One patient had a 3-year course of step-wise progressive tetraparesis; at each of the five events intramedullary bleeding from a cryptic vascular malformation at C6–7 level was diagnosed by MRI. The other patient presented with one episode which led to MRI diagnosis of a vascular malformation at the C2 level. Both patients eventually underwent complete surgical excision of the angioma with subsequent steady improvement of the neurological deficit.  相似文献   
18.
BACKGROUND CONTEXT: There is limited information describing the correlation between the initial quantitative measurements on magnetic resonance imaging (MRI) scans of disc herniation area, canal cross-section areas, percent canal compromise, and disc herniation location to the need for surgery. PURPOSE: Our aim is to determine if the size of disc herniation area, canal cross-section area, percent canal compromise, and disc herniation location taken from MRI images of patients with symptomatic single-level lumbar herniated intervertebral discs upon initial presentation to a spine surgeon, were predictive of the need for surgical treatment. STUDY DESIGN/SETTING: This is a retrospective case matched study of patient MRI images in the senior author's private practice. PATIENT SAMPLE: From a pool of 332 patients with sciatica caused by lumbar intervertebral disc herniations at our institution, 65 patients had surgery, of which MRI images were available and analyzed on 44 patients. Forty-four additional patients were randomly selected from the remaining 267 original group as nonoperative controls. METHODS: The axial MRI image showing the largest canal compromise by the herniated disc was selected for measurements. Using T1- and T2-weighted images, the areas of interest were digitally scanned at high resolution. The canal area and disc herniation area measurement were calculated from the total number of pixels per cross-sectional area, multiplied by a scan correction factor, mm(2) /pixel. Disc herniation locations were classified into either central or paracentral. The percent canal compromise was obtained by disc herniation area divided by canal cross-section area and multiplied by 100. RESULTS: The surgical group's overall mean herniated disc area was 219.6 square millimeter (mm(2)), 179.8 at L4-5, and 267.4 at L5-S1. The nonoperative group's overall mean herniated disc area was 178.4 mm(2), 135.1 at L2-3, 160.3 at L4-5, and 207.4 at L5-S1. The surgical group's overall mean canal cross-sectional area was 471.8 mm(2), 418.6 at L4-5, and 535.6 at L5-S1. The nonoperative group's overall mean canal cross-sectional area was 541.3 mm(2), 518.1 at L2-3, 446.8 at L4-5, and 669.9 at L5-S1. The overall percent canal compromise ratio in the surgery group was 46.7%, 44.1% at L4-5, and 49.8% at L5-S1. The overall percent canal compromise in the nonoperative group was 34.2%, 34.1% at L2-3, 36.1% at L4-5, and 31.8% at L5-S1. The percent canal compromise in central herniations at L4-5 level was 53.0% in the surgical group, and 32.8% in the nonoperative group; at the L5-S1 level surgical group percent canal compromise was 64.1% and in the nonoperative group canal compromise was 27%. L4-L5 level paracentral herniations canal compromise was 36.7% in the surgical group compared with 42.5% canal compromise in the nonoperative group. At the L5-S1 level the canal compromise was 45% in the surgical group and 34.8% in the nonoperative group. CONCLUSIONS: Our findings show a trend for patients treated with surgery to have larger disc herniation areas and smaller canal cross-section areas, corresponding to larger percent canal compromise than the nonoperative group. Centrally located herniations followed this trend closely at all levels studied. However, the paracentral herniation at the L4-5 level does not follow this trend, possibly because paracentral disc herniation clinical course is determined more by herniation location rather than the overall herniation size.  相似文献   
19.
特殊部位异位妊娠的临床分析   总被引:1,自引:0,他引:1  
目的探讨特殊部位异位妊娠的临床特点,误诊原因及治疗原则。方法对1996年1月至2003年12月诊治的256例特殊部位异位妊娠进行回顾性分析。结果特殊部位异位妊娠发生率占同期异位妊娠的3.36%,术前诊断率48.4%,所有的患者均行手术。视术中情况进行不同的处理,所得标本均经病理切片证实,全部患者愈后良好。结论特殊部位异位妊娠的临床表现不典型,容易漏诊误诊,一旦怀疑本病应尽早住院,及时明确诊断并手术,患者愈后良好。  相似文献   
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