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61.
Idiopathic spinal cord herniation is a rare spinal cord disorder caused by spinal cord prolapse through a adural defect. It is a curable disease, so early detection is of particular importance. We report a 38-year-old woman with Brown-Sequard syndrome which was caused by the thoracic spinal cord herniation. Her weakness was almost completely resolved after surgical management, which emphasizes the importance of early diagnosis and surgical management in this rare disease entity.  相似文献   
62.
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger, was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612 hours later.  相似文献   
63.
Summary The effect of brainstem stimulation was studied on neurones recorded intracellularly in the superficial and deeper laminae of the lumbosacral dorsal horn of the spinal cord in anaesthetised cats. Stimulation in the nucleus locus coeruleus (LC) produced a hyperpolarisation in 4/13 multireceptive neurones and produced a biphasic action consisting of a hyperpolarisation which was followed by a depolarisation in 3/13 neurones. These actions were produced irrespective of whether the multireceptive neurone was located in the superficial or deeper laminae of the dorsal horn. Stimulation failed to produce postsynaptic potentials in the remaining 6/13 multireceptive neurones. The amplitude of hyperpolarisation was increased by the passage of depolarising pulses through the recording microelectrode and decreased by hyperpolarising pulses. Stimulation in other brainstem areas such as, the lateral (FTL), paralemniscal (FTP) and central (FTC) divisions of the tegmental field and the nuclei raphe magnus (NRM) and reticularis magnocellularis (RMc) also hyperpolarised neurones in the dorsal horn. The polarity of hyperpolarisation evoked from some brainstem areas (FTP, FTC, RMc) could be reversed to depolarisation by the passive diffusion of ions from the recording microelectrode containing 3M-KCl. Brainstem (LC, NRM, FTP, FTL) stimulation generated long lasting (700 ms) hyperpolarisation on 4/4 selectively nocireceptive neurones of lamina I. There was, however, no effect on the activity of 5/5 neurones recorded in laminae I/II which in addition to receiving excitatory cutaneous inputs were inhibited by heat stimuli. Stimulation in LC also produced dorsal root potentials (DRPs) and reduced the amplitude of simultaneously recorded excitatory postsynaptic potentials (EPSPs) generated by the activation of primary afferent fibres in 3 multireceptive neurones. It is concluded that inhibition of nociceptive transmission in the spinal cord from LC and other brainstem areas may involve both pre- and postsynaptic mechanisms.  相似文献   
64.
65.
丹参注射液椎管内局部灌注对急性脊髓损伤的保护作用   总被引:7,自引:3,他引:4  
目的 探讨丹参对急性脊髓损伤的防治作用。方法 以改良Allen's法造成兔不完全性脊髓损伤的模型,硬膜下插管。随机分成丹参治疗组和对照组。术后按每天0.3ml/kg体重的总量分4次从硬膜下导管推入丹参注射液,对照组推入生理盐水。损伤后8、72h对脊髓损伤区进行过氧化物歧化酶(SOD)、丙二醛(MDA)、组织形态学观察、神经元凋亡、bcl-2等进行评价。结果 丹参组SOD含量高于对照组(P<0.01),MDA含量低于对照组(P<0.01)。细胞凋亡数目TUNEL法丹参组低于对照组(P<0.01),流式细胞术检测凋亡丹参组低于对照组(P<0.05)。bcl-2的表达丹参组高于对照组(P<0.05)。神经元及神经纤维变性、坏死轻于对照组。结论 丹参能改善损伤脊髓微循环,抑制和减轻脊髓损伤后的两种死亡方式坏死和凋亡。  相似文献   
66.
目的 总结 17例胸椎骨折患者的特点与诊疗情况 ,为提高此类合并胸外伤患者的疗效提供有效的治疗方案。方法 分析了 17例胸椎骨折患者的临床特点、诊疗经过、近远期随访结果。结果  14例 (82 .4 % )合并肋骨骨折 ,11例 (6 4 .7% )合并血气胸 ,10例 (5 8.8% )合并严重脊髓伤 ,3例 (30 % )远期脊髓伤为有用恢复。结论 胸椎骨折常合并肋骨骨折、血气胸、严重脊髓损伤 ,预后较差 ,为此应重视合并胸外伤的胸椎骨折的围手术期处理  相似文献   
67.
小干扰RNA干扰大鼠神经元Nogo受体mRNA表达的实验研究   总被引:2,自引:2,他引:0  
目的观察大鼠Nogo受体(NgR)特异性小干扰RNA(small interfering RNA,siRNA)在原代神经元干扰其mRNA表达的效果。方法体外培养大鼠原代皮层和海马细胞,应用阳离子脂质体转染试剂转染4对化学合成的大鼠NgR特异性siRNA,72h后提取细胞总RNA,实时荧光定量RT-PCR检测NgR mRNA表达情况。结果4对siRNA均能够下调靶基因NgR的mRNA表达水平,siNgR199、siNgR562、siNgR772和siNgR964等干扰后,NgR mRNA的表达分别为对照siRNA干扰组的6.5%、62.4%、15.2%和6.86%,与对照siRNA干扰组比较有统计学意义(P<0.05)。结论化学合成的NgR特异性siRNA能够有效的干扰大鼠原代皮层和海马细胞内NgR基因mRNA的表达水平。  相似文献   
68.
血清和精浆抑制素B在无精子症诊断中的应用研究   总被引:4,自引:1,他引:3  
目的:评价血清和精浆抑制素B浓度在诊断梗阻性和非梗阻性无精子症中的应用价值。方法:测定25例正常生育者(正常对照组),37例梗阻性无精子症以及33例非梗阻性无精子症者的血清卵泡刺激素(FSH)、血清和精浆抑制素B浓度,对无精子症者行睾丸病理Johnsen评分。结果:精浆和血清抑制素B浓度比值在正常对照组和非梗阻性无精子组分别为2.17和3.63,差异无显著性(P=0.29);在梗阻性无精子症组两者比值为0.18,与正常对照组和非梗阻性无精子症组比较显著降低(P<0.01)。结论:精浆和血清抑制素B浓度比值可用于临床诊断梗阻性和非梗阻性无精子症。  相似文献   
69.
皮下环精索封闭疗法治疗急性附睾-睾丸炎疗效观察   总被引:2,自引:0,他引:2  
目的评价急性附睾-睾丸炎皮下环精索封闭疗法的疗效.方法对80例急性附睾-睾丸炎病例随机分为两组,对照组给予传统治疗方法,而治疗组除了传统疗法外,加用皮下环精索封闭治疗.结果治疗组所有患者1~3d内发热、疼痛症状缓解,4~6 d内附睾睾丸肿胀明显减退,97.5%的病例2周内治愈;而对照组40%的患者1~3d内发热、疼痛症状缓解,75%的患者4~6d内附睾睾丸肿胀减退,80%患者2周内治愈,治疗组疗效优于对照组.结论皮下环精索封闭疗法可以迅速缓解临床症状,缩短病程,提高治愈率,是治疗急性附睾-睾丸炎的有效方法.  相似文献   
70.
目的 评价控制性降压是否增加脊髓对牵拉损伤的易感性。材料与方法健康成年杂种犬6只,随机分为常压和控制性降压脊髓牵拉损伤组。观察常压及控制性降压水平下相同程度牵拉损伤后脊髓血流(SCBF)、体感诱发电位(SEP)、神经源性运动诱发电位(NMEP)改变的差异。结果 外周血有创动脉压(MABP)平均下降幅度为40.5%。经SSPS统计软件独立样本t检验,不同牵拉水平下,常压组及低压组的SCBF(%)、SEP波幅(Asep)(%)及NMEP波幅(%)无显著差异。结论 尼卡地平控制性降压不增加脊髓对牵拉损伤的易感性。  相似文献   
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