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41.
目的:探讨家兔阴茎感觉神经来源。方法:健康成年雄性新西兰白兔12只,随机均分为两组:每组6只,A组在左侧脊神经上记录,B组在右侧脊神经上记录。对家兔阴茎施加不同大小的机械刺激,用神经单纤维记录技术,在同侧S1~S4脊神经上记录单纤维放电。结果:通过对家兔阴茎施加各种不同机械刺激,在同侧S2~S3脊神经上能记录到放电,S1、S4脊神经上未能记录到放电。左侧脊神经放电纤维数量分别为:S2:39.67±3.14,S3:21.00±2.19;右侧脊神经放电纤维数量分别为:S2:40.00±3.16,S3:19.67±2.58,左右侧差异无显著性(P>0.05)。结论:家兔阴茎皮肤感觉来源于S2~S3脊神经。  相似文献   
42.
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   
43.
目的研究两种不同脊柱后路减压方法治疗胸腰段骨折脱位合并脊髓损伤的手术治疗效果。方法回顾分析本院1996年3月~2002年6月收治的胸腰段骨折脱位并脊髓损伤患者76例,按不同减压方法将其分为两组:切除一侧或两侧椎板、椎弓根或部分关节突行侧前方环状减压AF内固定者40例,为直接减压组;体位复位结合AF器械矫正复位36例,为间接减压组。统计学分析,两组资料具有可比性。对术后神经功能恢复情况,按ASIA神经功能评定标准进行评定。中晚期并发症,根据是否有腰背痛,下肢根性痛、麻木无力,两便功能障碍进行评定。生活能力按FIM评定。结果两组病例获6个月~5年随访,结果表明,术前脊髓完全性损伤,术后均无恢复;术前脊髓不完全性损伤,术后两组间比较差异无显著性。中晚期并发症发生,直接减压组高于间接减压组;术后生活自理能力,间接减压组好于直接减压组。结论间接减压手术方法治疗胸腰段骨折脱位合并脊髓损伤不失为一种早期治疗的首选方法。  相似文献   
44.
The purpose of this study was to determine if changes in hindlimb motoneuron membrane electrical properties occur 4–6 months after spinal transection in the adult animal. Eight acute and nine chronic animals were spinalized at T12. Intracellular recordings from motoneurons innervating the triceps surae were performed. Membrane electrical properties, including resting potential, action potential peak amplitude, afterhyperpolarization duration, rheobasic current, input resistance and axonal conduction velocity were measured. There were no statistical differences found between group means or frequency distributions in the membrane properties of motoneurons assessed from acute and chronic spinal animals. Thus, alteration of motoneuron membrane properties does not appear to be a major contributing factor to the hyperexcitable hindlimb reflex activity demonstrated by chronic spinal animals.  相似文献   
45.
同种异体骨与自体骨移植治疗青少年脊柱侧凸的比较研究   总被引:3,自引:1,他引:2  
[目的]观察同种异体骨移植与自体骨移植治疗青少年脊柱侧凸的临床效果.[方法]对1996~2006年本科收治的63例青少年脊柱侧凸患者的临床资料,采用回顾性"病例-对照"研究方法进行分析,A组(同种异体骨移植组)32例,10~15岁,平均12.2岁;Cobb's角38°~113°,平均62°;B组(自体髂骨移植组)31例,年龄9~14岁,平均12.4岁;Cobb's角41°~105°,平均54°.所有患者均选择中华长城椎弓根内固定系统经后路矫正,术后定期随访并对临床效果进行评估.[结果]出院后2个月即开始随访,随访时间18~24个月,平均26个月;亦无严重并发症发生;A组的手术时间、失血量较B组患者减少,组间具有统计学意义(P<0.01).[结论]两组患者具有相似的临床效果,在严格掌握适应证,充分术前准备、正确手术操作、及时术后处理的前提下,同种异体骨移植能够有效替代自体髂骨移植治疗青少年脊柱侧凸.  相似文献   
46.
Naloxone, an opioid peptide antagonist, has been reported to facilitate voiding in neurologic bladder disorders, but its effects on the neural micturition reflex arc are poorly understood. We studied the effect of naloxone in 34 male adult cats, spinalized at C5-C6 level 7 to 119 days previously. Each cat served as its own control. The following tests were performed: Urethral pressure profiles, cystosphincterograms with the urethro-vesical junction opened and closed and mechanograms of the detrusor, and the circular and longitudinal urethral muscles. The study included (1) the effects of anesthesia of the bladder and pelvic nerve, as well as that of the urethral and pudendal nerves; (2) the action of naloxone; and (3) the action of oxymorphone. Our results demonstrated that naloxone (1) increased somatic (osteotendinous and nociceptive) reflexes and aggravated spasticity; (2) increased vegetative micturitional and sexual reflexes, in particular the urethra-urethral contraction reflex, aggravating the spasmodic contractions of the external sphincter; and (3) increased the frequency and intensity of the mass reflex. In consequence, we suggest that naloxone is contraindicated in cases of spinal cord lesions with detrusor-sphincter dyssynergia syndrome.  相似文献   
47.
双节段人工腰椎间盘置换术的疗效与探讨   总被引:1,自引:0,他引:1  
[目的]观察采用以双段SB Charite Ⅲ人工椎间盘置换术治疗退变性腰椎间盘疾病的l临床结果并探讨其可行性。[方法]自2000年10月至2006年8月,对22例L4-S1退变的病例采用双节段人工腰椎间盘置换术,男16例,女6例;年龄43~54岁,平均48岁;均获得随访,随访时间10—61个月(平均37.4个月),分别于手术前后对患者的情况进行JOA评分和影像学对比。[结果]术后病例JOA评分较术前显著提高(P〈0.05)。按FRANKLE标准,JOA评分改善率1年后优12例,良7例,可3例;3年后共获得随访18例,其中优10例,良5例,可3例。术后X线片显示人工椎间盘位置正确,椎间隙高度恢复正常,椎间活动度得到维持。15例患者返回原工作,2例变换工作,1例退休。所有病例无假体功能并发症发生,无假体松动、半脱位、下沉。[结论]在严格适应证的前提下,双节段人工椎间盘置换术是可以获得满意临床疗效的,可在有条件的医院积极开展。  相似文献   
48.
Objective: Severe scoliosis refers to scoliosis with serious and stiff curve. It always combins with trunk imbalance in coronal and sagittal contour. Besides complex pathological changes, cardiopulmonary deficits and other concomitant diseases increase treatmental difficulties. So the treatment of severe scoliosis is always a great challenge to spine surgeon. Methods :Thirty-six patients with severe scoliosis received one stage posterior correction followed by anterior release during July 1997 to January 2003, including 9 males and 27 females. Mean age was 17.2 years. Of them, 33 was idiopathic scoliosis and 3 was neurofibromatosis scoliosis( Cobb angle: 85-116 degree); 20 cases were abnormal in sagital plane. Three-dimensional devised instrumentation were applied such as CD, CD-Horizon, TSRH or Isola in posterior procedure followed by anterior release during the same anesthesia. 31 cases of this group received thorac icplasty. Results: The correction in the frontal plane achieved an average of 48.5%. In the sagittal plane, the pathological shape of the spine was reduced and distinctly ameliorated. 80. 6% of the patients maintained or achieved balance of sagittal plane. There were no complications of severe neurological deficit, hook displacement, rod broken, and deep infection at follow-up. One case occurred traumatic pleurisy after operation and another appeared pseudarthrosis 2 years later. One case demonstrated imbalance 11 months after operation. One patient was presented loss of correction more than 10 degree at one year follow-up and 5.2 degree in average. Conclusion:The study indicates that the one stage posterior correction combined with anterior release in treatment of severe scoliosis can achieve satisfactory correction. Appropriate choice of cases, preoperational detailed assessment and application of SEP and wake-up test during operation can possibly reduce severe complication. The long-term outcomes still need further observation.  相似文献   
49.
We present a case of acute bowel obstruction in an immunocompromised child, who also had lobar pneumonia and a giant unilateral pneumatocele. She was successfully managed with subarachnoid anaesthesia for exploratory laparotomy to relieve a colonic obstruction. This proved to be a safe alternative to general anaesthesia with tracheal intubation in this patient and should be considered in infants and children in selected cases whenever a contraindication to general anaesthesia exists.  相似文献   
50.
Nociceptin (Orphanin FQ) is a newly discovered endogenous heptadecapeptide substrate for the opioid-receptor-like 1 receptor, a G protein coupled receptor that bears striking amino acid sequence homology to opiate receptors. In rats, intrathecal (i.t.) administration of nociceptin is without effect on basal thresholds for responsiveness to electric foot shock. However, during either late gestation or its hormonal simulation, when nociceptive thresholds are elevated by approximately 70%, i.t. nociceptin substantially attenuates jump thresholds in a dose-dependent fashion. This hypoalgesic effect of nociceptin is not limited to attenuating the gestational or sex steroid-induced increment in pain thresholds. Following the highest i.t. dose of nociceptin employed (20 nmol), the gestational or sex steroid-induced increment in jump thresholds is not only abolished but a significant hyperalgesia is observed. These results underscore the importance of the hormonal milieu to nociceptin hypoalgesic sensitivity. The potential contribution of spinal nociceptive pathways that utilize nociceptin to the etiology of extraordinary painful pregnancy and labor should not be ignored.  相似文献   
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