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11.
12.
用5只猫于左侧颈部食管壁内注入 HRP 溶液,通过 HRP 逆行追踪法研究颈部食管的交感神经支配,结果表明:1.长轴突型交感节前神经元直接分布到食管壁内,其标记细胞位于双侧脊髓的胸1~3节段,以胸2节段最多(占标记细胞总数的66.45%),注射侧占优势。标记细胞主要位于中间带外侧核(约占95.02%),其次为侧索、中介核、前角腹后外侧核。其细胞形态不一,以中小型细胞为主(占标记细胞总数的90.4%)。2.支配颈部食管的交感节后神经元主要位于星状神经节(约占61.99%),余者位于双侧颈前、中和2~5胸交感节内、以小细胞最多。  相似文献   
13.
To compare nerve regeneration in young adult and aging mice, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two weeks later, both groups of mice were perfused with an aldehyde solution, and, after additional fixation, the sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. The same level was sectioned in unoperated contralateral nerves; these nerves served as controls. Electron micrographs and the Bioquant Image Analysis System IV were used to measure areas of posterior tibial fascicles and count the number of myelinated axons, the number of unmyelinated axons, and their frequency in Schwann cell units. In aging mice, the total number of regenerating myelinated axons was significantly reduced, but totals of regenerating unmyelinated axons in aging and young adults did not differ significantly. In aging mice, the frequency of Schwann cells that contained a single unmyelinated axon was greater, suggesting that before myelination began, Schwann cell ensheathment of axons also was slowed. After axotomy by a crush injury, the area of the posterior tibial fascicle was less than that in young adults and the distal disintegration of myelin sheath remnants also appeared to be retarded. The results indicate that responses of neurons, axons, and Schwann cells could be important in slowing the regeneration of myelinated fibers found in sciatic nerves from aging mice.  相似文献   
14.
Femoral and lateral cutaneous nerve of the thigh blocks have been performed in a group of 50 children; the method has not previously been described in paediatric practice. The technique was judged to have been successful in 48 (96%) of the children. There were no early or late complications. It is concluded that these blocks are easy to perform, even in small children and infants, and that they can produce reliable postoperative analgesia for a variety of orthopaedic and plastic procedures.  相似文献   
15.
The pattern evoked electroretinogram (PERG) was investigated in 11 patients with unilateral optic nerve disease and in a series of age-matched controls. The visually evoked potential (VEP) was also measured. The PERG showed a similar reduction to the VEP in optic nerve disease. Serial studies indicate that the PERG may not be affected immediately in some instances but may show a gradual decline over several months.  相似文献   
16.
目的 探讨实验性内听动脉阻断与术后听力改变的关系及术中听觉监控的方法。方法 实验兔乙状窦后进路暴露小脑桥脑角,下压小脑暴露内听道及第Ⅷ神经复合体,分辨出内听动脉,予阻断不同时间,分别行蜗神经直接复合动作电位(DCAP)和畸变产物耳声发射记录(DPOAE)。结果对照组DCAPN1波潜伏期值无明显改变。内耳血供阻断10s和30s组在压迫开始后3min,DCAPN1波潜伏期值均恢复为初始值。内耳血供阻断1min组在压迫开始后3h,DCAPN1波潜伏期值未恢复为初始值假手术组DPOAE幅值无明显改变,内耳血供阻断10s、30s对DPOAE幅值无影响,内耳血供阻断1min使得DPOAE幅值下降结论兔内耳血供阻断1min可能造成兔听觉不可逆损伤。DCAP、DPOAE能有效、持续地监控内耳血供阻断,是耳神经外科手术中实用的听觉监测手段。  相似文献   
17.
周围神经端侧动脉套接后神经再生的研究   总被引:6,自引:2,他引:4  
目的研究周围神经端侧动脉套接后神经再生的可能性及其特点. 方法取SD大鼠75只,在股骨中下段切断腓神经,将近断端逆转90度包埋于肌肉中.随机分为5组.A组:将截取的左颈总动脉套接于右侧正常胫神经侧方与腓总神经远端2 mm距离之间,缝合部胫神经外膜不予切除;B组:在胫神经套接部外膜开窗1.0 mm;C组:腓总神经切断14天后再予动脉套接,余同B组;D组:同B组,且于动脉套接部注入神经生长因子(neural growth factor, NGF)1 ml;E组:将腓总神经远端以端侧缝合形式直接缝合于胫神经的一侧,外膜开窗1.0 mm.术后4、8和12周分别行组织学、电镜和神经纤维计数等检查. 结果 4周时C、D及E组周边区域有神经纤维轴突和髓鞘再生,A组则无神经纤维生长; 8周时C、D及E组再生神经纤维较B组多,E组神经纤维较C、D组多,差异有统计学意义(P<0.05); 12周时C、D及E组神经纤维多于B组,差异有统计学意义(P<0.05);C组及D组有较丰富的神经再生,与神经端侧直接吻合的E组差异无统计学意义(P>0.05). 结论神经端侧2 mm距离动脉套接可作为修复周围神经损伤的一种可行方法.  相似文献   
18.
Abstract 10 embalmed cadaver forearms and wrists were dissected to determine the anatomical course of the superficial branch of the radial nerve in the distal forearm. The superficial radial nerve bifurcated in two branches at a mean of 54,7 mm proximal to the radial styloid. From the styloid process of the radius, the mean distance to the closest dorsal branch of the superficial radial nerve was 3,5 mm and the mean distance to the closest volar branch was 9,8 mm. The mean distance between the closest branch of the superficial radial nerve and Lister?s tubercle was 16,4 mm. The crossing point between the nerve and the cephalic vein was located at a mean of 54,3 mm proximal to the styloid process. At the level of styloid process the mean distance between the closest dorsal branch of the superficial radial nerve and the first dorsal compartment was 15,2 mm and between the closest volar branch and the first dorsal compartment 4,4 mm. Detailed knowledge of anatomic characteristics of the superficial branch of the radial nerve may help prevent injury during operations and treat traumatic lesions of the nerve. Because of great variations in the course of the superficial radial nerve we could not define an absolute safe zone for surgical procedures on the distal forearm. Iatrogenic lesions of the superficial radial nerve are described complications of percutaneous procedures. Therefore open surgical approaches are recommended. Daniela Klitscher and Lars Peter Müller contributed equally to this work.  相似文献   
19.
PURPOSE: To determine the effect of an interposition nerve graft on sexual function after radical prostatectomy. METHODS: This study includes 64 patients, without hormonal therapy, who underwent a radical prostatectomy and intraoperative electrophysiological confirmation of cavernous nerve preservation. Twelve patients underwent a unilateral interposition sural nerve graft (UNG) for the resected neurovascular bundle. Twenty-one and 31 patients underwent bilateral nerve-sparing (BNS) and unilateral nerve-sparing (UNS) surgery without a nerve graft, respectively. As the age of patients was significantly younger in the UNG group than in the other groups, age-matched analysis also was conducted. Sexual function, evaluated by a self-administered questionnaire using the University of California Los Angeles-Prostate Cancer Index, was compared statistically among the three groups. RESULTS: In the age-matched analysis, the postoperative sexual function (SXF) score of the UNG group showed an intermediate level of recovery between those of the BNS and UNS groups at 12 months and reached the same level as the score at 12 months of the BNS group at 18 months postoperatively. The difference in the SXF score between the UNG and UNS groups began to appear after 6 months postoperatively and increased steadily with time. However, the background factors, such as the baseline SXF score, the usage rate of phosphodiesterase 5 inhibitors, and the rate of comorbidities were different between the UNG and UNS groups. CONCLUSIONS: The difference of the SXF score between the UNG and UNS groups increased with time after 6 months postoperatively. However, it might be difficult at present to attribute a better recovery of the SXF score to the nerve graft because of the difference in the background factors between the groups.  相似文献   
20.
目的:探讨小儿腮腺炎并发中枢神经系统感染的临床特点.方法:对52例小儿腮腺炎并发中枢神经系统感染的临床资料进行回顾性总结分析.结果:3~7月份为小儿腮腺炎并发中枢神经系统感染的发病高峰季节(92.31%).发病年龄以6~12岁为主(82.69%),多发生于腮腺肿痛3天以上伴有持续发热者(78.85%),少数患者同时有其它脏器的损害,一般治疗疗效较好.结论:腮腺炎极易并发中枢神经系统感染,年长儿发生率高,应推广接种流腮活疫苗降低发病率.  相似文献   
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