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101.
102.
目的:探讨背根神经节(DRG)内P物质(SP)、降钙素基因相关肽(CGRP)免疫阳性神经元与阴茎包皮系带感觉信息传递之问的关系。方法:通过荧光金(FG)逆行标记对大鼠阴茎包皮系带内神经末梢的来源作追踪定位,并结合SP、CGRP免疫荧光标记法,研究大鼠DRG内FG标记阳性神经元中SP、CGRP免疫阳性神经元的形态和分布。结果:FG逆行标记结果发现,大鼠阴茎包皮系带内的神经末梢起源于第6腰髓对应的背根神经节(L6-DRG)和第1骶髓对应的背根神经节(S1-DRG)的神经元。对这些神经元分别作SP、CGRP免疫荧光标记后发现,标记细胞大小不等,分别呈深红色和深绿色,沿神经束成行排列或散在分布。FG/SP、FG/CGRP双标记阳性细胞均为中小型,其数量分别占FG逆行标记阳性细胞总数的1/3和1/2,FG/SP/CGRP三标记阳性细胞占FG逆行标记阳性细胞总数的1/5。结论:大鼠L6-DRG和S1-DRG内的SP、CGRP免疫阳性神经元可能参与阴茎包皮系带感觉信息的传递。  相似文献   
103.
BACKGROUND AND OBJECTIVE: To compare the effectiveness of antimicrobial photodynamic therapy (PDT), standard endodontic treatment and the combined treatment to eliminate bacterial biofilms present in infected root canals. STUDY DESIGN/MATERIALS AND METHODS: Ten single-rooted freshly extracted human teeth were inoculated with stable bioluminescent Gram-negative bacteria, Proteus mirabilis and Pseudomonas aeruginosa to form 3-day biofilms in prepared root canals. Bioluminescence imaging was used to serially quantify bacterial burdens. PDT employed a conjugate between polyethylenimine and chlorin(e6) as the photosensitizer (PS) and 660-nm diode laser light delivered into the root canal via a 200-micro fiber, and this was compared and combined with standard endodontic treatment using mechanical debridement and antiseptic irrigation. RESULTS: Endodontic therapy alone reduced bacterial bioluminescence by 90% while PDT alone reduced bioluminescence by 95%. The combination reduced bioluminescence by >98%, and importantly the bacterial regrowth observed 24 hours after treatment was much less for the combination (P<0.0005) than for either single treatment. CONCLUSIONS: Bioluminescence imaging is an efficient way to monitor endodontic therapy. Antimicrobial PDT may have a role to play in optimized endodontic therapy.  相似文献   
104.
目的设计颈椎前路椎管扩大术式并探讨该术式的可行性,为颈椎管多节段狭窄症提供新的手术方法。方法标本实验:选用4具C1~T1尸体颈椎标本,去除前方肌肉,保留后侧肌肉及固有韧带,解剖出横突孔,沿椎动脉走行,穿入直径3mm橡胶管,注入造影剂。沿C4~6椎体前正中纵行劈开,依次横向撑开3、6、9、12mm,并用木块填塞,三维CT下观察椎管前后径、横径、截面积、两侧椎动脉的直径、间距,神经根管变化。动物实验:用4只成年绵羊,麻醉后暴露出C3,4颈椎前方,将C3,4椎体纵向劈开,横向撑开9mm,取同侧胫骨9mm×9mm×15mm骨块植入撑开区。术后观察四肢运动恢复情况。结果标本在撑开3、6、9mm后,椎管前后径平均增加1.14%、3.53%、5.15%,横径增加7.92%、14.62%、22.74%,截面积增加8.52%,17.99%,25.01%;在撑开3、6、9mm时,两侧椎动脉走行间距平行,撑开12mm时,在C3,4和C6,7椎间椎动脉间距相差2mm,但走行无折屈、受压。撑开前后神经根管各径及长度无变化。标本在撑开3、6、9mm时未见骨折,撑开12mm时2具左侧、1具右侧椎板靠近棘突部骨折,均为裂纹骨折,无移位。4只绵羊术后第2d四肢可以自由行走,无神经、血管损伤征兆。结论经前路颈椎体纵向劈开扩大术,可以增加椎管容积、不影响脊柱三柱稳定结构。动物实验表明椎体横向撑开一定范围内(≤9mm)对颈髓及周围组织无损伤迹象。实验结果初步证实经前路颈椎椎管扩大术安全有效。  相似文献   
105.
退变性症状性腰椎侧凸的手术治疗   总被引:2,自引:1,他引:2  
[目的]探讨后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术式治疗退变性症状性腰椎侧凸的临床效果。[方法]1999年1月-2006年4月,采用经后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术式治疗退变性症状性腰椎侧凸37例,男21例,女16例;年龄51—82岁,平均62.6岁。所有病例拍摄腰椎正侧位片及Bending片,常规备CT和MRI。根据患者下肢症状行全椎板或半椎板减压,神经根扩大,椎间植骨融合及椎弓根螺钉间断固定。[结果]本组病例均获随访(1—6年,平均2年零7个月),术后临床症状均明显缓解,按JOA评分,手术疗效优良率91.9%,侧凸平均矫正率54.8%。随访期间无明显矫正度数及椎间隙高度丢失,术后3个月、1年复查X片内置物无松动及断裂,植骨融合时间平均11.6周。[结论]对于退变性症状性腰椎侧凸患者:(1)采取个体化治疗,年龄不是绝对手术禁忌证,病程长短不是决定手术疗效的重要指标;(2)后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术是安全有效的理想术式。  相似文献   
106.
目的:评价头灯辅助下小切口手术治疗腰椎间盘突出并神经根管狭窄症的优点及临床疗效。方法:采用冷光源头灯(Heine3S LED headlight)辅助下小切口手术治疗腰椎间盘突出并神经根管狭窄症45例,男32例,女13例;年龄36~68岁,平均53.6岁;病程6~72个月,平均29.5个月。结果:28例患者术后次日原有腰腿痛症状消失,17例症状明显减轻。经6~14个月(平均8个月)的随访,依据JOA29分法进行疗效评分,由术前7~15分(平均11.6分)改善至术后26~29分(平均28.2分),平均改善率为93.1%。结论:冷光源头灯辅助下小切口手术治疗腰椎间盘突出并神经根管狭窄症具有损伤小、操作方便、直视视野清晰、不影响脊柱的稳定性、减压彻底、疗效确实等优点。  相似文献   
107.
Summary When there is significant loss of spinal dura mater, dural substitution with synthetic or allogenic materials is essential. In the case of laminectomy, mechanical protection and reformation of the dorsal spinal canal may be useful. This is a report on a patient with total dura loss through tumour atrophy of the dura and laminae. In order to reconstruct the dorsal face of the spinal canal a polylactide sheet was cut and shaped to fit the physiological contour. A bovine dura substitute was firmly attached and sutured to the inner surface of the polylactide shield. The implant was wedged in between the pedicles and the facet joints and resulted in a water-tight dura substitute maintaining the shape of the spinal canal and protecting it against mechanical forces and intradural scar formation.  相似文献   
108.
Activation of spinal N-methyl-D-aspartate (NMDA) receptors and then the nitric oxide and the arachidonic acid pathways is important in pain transmission. This study assessed the effects of the NMDA receptor channel blocker ketamine, the nitric oxide synthase inhibitor L-NAME, and the cyclooxygenase inhibitor ketoprofen in nociceptive transmission using an in vitro neonatal rat spinal cord preparation. Supramaximal electrical stimulation of the dorsal root evoked the A-fibre- and C-fibre-mediated high intensity excitatory postsynaptic potential (EPSP) in the ipsilateral ventral root. Low intensity stimulation evoked the A-fibre-mediated monosynaptic compound action potential (MSR) superimposed on the low intensity EPSP. Both the low intensity EPSP and the high intensity EPSP contain NMDA-receptor-mediated components. Only ketamine and ketoprofen depressed the synaptic responses. Ketamine depressed all three spinal reflexes with IC(50) values (with 95% CI) of 10.80 microM (5.97 to 19.54 microM) for the MSR, 8.29 microM (4.53 to 14.17 microM) for the low intensity EPSP, and 5.35 microM (3.05 to 9.40 microM) for the high intensity EPSP. Ketoprofen depressed the low intensity EPSP and the high intensity EPSP only; IC(50) values (with 95% CI) were 354.5 microM (217.5 to 576.8 microM) and 302.7 microM (174.0 to 526.7 microM), respectively. Reflexes recovered after drug washout. These data demonstrated that ketamine and ketoprofen, but not L-NAME, depressed NMDA-mediated nociceptive transmission in spinal cord preparations from neonatal rats.  相似文献   
109.
Herniated intervertebral disc causes in a great number of cases of lumbar nerve root compression, especially in the segment L5/S1. Other reasons responsible for stress to the lumbar spinal root are the spinal canal stenosis and the postdiscotomy syndrome. For patients without neurological deficiencies, the conservative treatment includes different epidural injection techniques. Steroids are often applied. A specific injection technique needing only a small drug amount is the epidural perineural approach using a special two-needle technique. The anatomical spaces of the nerve roots have received little attention in therapy. We have determined the anterolateral epidural space nerve volume of the nerve root L5/S1, and compared the data collected in an anatomical study with operative measurements during discectomy. The volume determination in the human cadavers was performed with liquid silicone filling the anterolateral space after dissection. The in vivo measurements were performed during surgery at the site of the anterolateral space after discectomy. The anatomical studies showed us a mean value volume of 1.1 ml. The surgical volume determinations result in a mean volume of 0.9 ml. A better understanding of the anterolateral epidural space may allow a reduction of the injection volume in the conservative nerve root compression treatment, especially using the epidural perineural technique, avoiding the risk of side effects of high doses of steroids.  相似文献   
110.
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