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51.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization.  相似文献   
52.
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process.  相似文献   
53.
脊髓手术中体感诱发电位监测的临床研究   总被引:3,自引:0,他引:3  
报告30例脊髓手术中体感诱发电位(SEP)连续监测的临床研究结果。SEP记录包括脊髓SEP(SSEP)和皮层SEP(SCEP)。麻醉药物对SEP有一定程度影响,SCEP相对较大。认为,至少术中SEP潜伏期延长不超过8%和波幅降低不超过50%,不会引起术后并发症,超过该范围由于病例较少,尚不能肯定与预后的关系,需进一步探讨。  相似文献   
54.
The case of a child injured by a knitting needle penetrating transorbitally and intracranially, resulting in carotid cavernous fistula and pontine injury, is reported. After receiving medical and endovascular treatment, the only remaining abnormal neurological manifestation was right peripheral facial nerve palsy. The clinical sequences of events and the demonstration of a pontine lesion leading to peripheral facial palsy are presented. Facial nuclear injury with a penetrating trauma is an extremely rare condition. It is important to identify the anatomical regions injured in penetrating traumas. The lesions must be identified by computerized tomography, magnetic resonance imaging, clinical and laboratory investigation.  相似文献   
55.
目的寻求健侧C7神经根移位治疗全臂丛神经根性撕脱伤手术中尺神经与桡神经的最佳吻合部位。方法在10具20侧福尔马林固定的成人尸体上肢标本上观察桡神经及其肱三头肌肌支的解剖学特征;尺神经的解剖学特征;尺神经不同水平与对侧颈根部的距离。结果桡神经从后侧束发出部位到发出肱三头肌长头的第一支肌支之间的距离为(8.2±1.4)cm,从发出长头的第一个肌支部位到外侧头最后一个肌支发出部位之间的距离为(4.8±0.7)cm。尺神经肘部以上几乎无分支,尺神经在发出部位的直径为(6.7±0.6)mm;在肘部的直径为(6.3±0.5)mm;在腕部的直径为(4.0±0.4)mm;从锁骨下尺神经发出部位到肘部的长度为(29.0±2.6)cm;从锁骨下尺神经发出点到对侧颈根部的距离为(18.0±1.8)cm。结论健侧C7神经根移位修复桡神经,尺神经与桡神经的最佳吻合部位是锁骨下区,在此部位吻合不但能保证肱三头肌功能恢复,而且大大缩短桥接神经的长度。  相似文献   
56.
Summary BACKGROUND: Sacral nerve stimulation (SNS) is an option for the treatment of fecal incontinence in patients with morphologically intact, but weak external anal sphincter. METHODS: In ten patients a percutaneous test-SNS was performed. Two patients suffered from fecal incontinence after surgery, one patient after incomplete leg palsy after traumatic spine injury and seven patients from idiopathic incontinence. Incontinence score, anorectal manometry and patient diary were performed before and after test-SNS. RESULTS: Intraoperative response (Bellows action) could be achieved in 90% of patients. Test-SNS was successful in 50% of patients. In these patients, resting pressure was increased by 100.1% and squeeze pressure by 84.5%. CONCLUSIONS: SNS is an effective therapy in a subset of patients with fecal incontinence. Fifty percent of patients tested are eligible for implantation of a permanent stimulation device.   相似文献   
57.
小脑延髓池的显微外科解剖研究   总被引:1,自引:1,他引:0  
目的研究小脑延髓池的显微外科解剖特征,探讨其临床意义.方法选择经10%福尔马林固定成人头颈标本15例,显微镜下(5~25倍)模拟枕下极外侧入路、颈-乳突入路和耳前颞下窝入路的手术操作,分别自后、侧和前方显露小脑延髓池内结构,详细观测其神经血管结构的形态特征.结果小脑延髓池位于延髓外侧,上至桥延沟,下达枕骨大孔,侧方沿枕骨形成蛛网膜袖套进入颈静脉孔和舌下神经管.舌咽神经、迷走神经和副神经的根丝自上而下起自橄榄体背侧、延髓和脊髓的后外侧沟,根丝逐级汇合后分别进入舌咽神经道和迷走神经道.椎动脉于小脑延髓池的下端入颅后经该池行向前上内进入延髓前池.小脑下后动脉(PICA)可分为延髓前段、延髓侧段、扁桃体延髓段、脉络膜扁桃体段和皮质段.主要的静脉有小脑延髓裂内静脉、延髓静脉、小脑岩面下组静脉和岩下桥静脉.结论小脑绒球和Luschka孔脉络丛复合体及颈静脉孔硬膜返折可作为辨认舌咽神经脑池段的解剖标志,深刻认识小脑延髓池的蛛网膜界限对手术处理累及小脑延髓池的不同性质病变,保护重要神经功能意义重大.  相似文献   
58.
目的 为研究皮肤疾病和损伤提供皮神经构筑资料。方法 用S 10 0蛋白免疫组化染色法研究正常成人颈前部胸锁乳突肌前、后缘皮肤各层内皮神经的数量、分布及构筑特点。结果  ( 1)皮肤乳头层内皮神经的小分支多分布在皮突下和乳头内血管丛附近。 ( 2 )真皮网状层内神经多位于小血管附近和汗腺、皮脂腺以及毛囊周围 ,神经分支呈串珠状或波纹形。 ( 3 )皮下组织内神经干和神经网同时存在。结论 皮肤内感觉神经树的分布及构筑特点与血管树相似。  相似文献   
59.
Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.  相似文献   
60.
目的:通过在神经缺损处局部回输体外分离培养纯化的淋巴细胞,了解此种方法促进面神经损伤修复的效果。方法:将20只Wistar大鼠的面神经颊支剪断并立即缝合(其余3支反折缝合)制成面神经损伤模型大鼠,将其分成淋巴细胞组和对照组,每组10只,每组再分成2周组和8周组。淋巴细胞组局部回输体外分离培养的外周血淋巴细胞,对照组作对照。于2周和8周测定面神经颊支-触须肌复合动作电位传导速度,辣根过氧化物酶(HRP)神经逆行示踪测定面神经核团的神经元阳性数目。结果:淋巴细胞组面神经颊支-触须肌复合动作电位传导速度8周时为0.64±0.07,与对照组(0.56±0.07)相比,差异有统计学意义(P<0.05)。HRP神经逆行示踪测定面神经核团神经元阳性数目,淋巴细胞组2周及8周与对照组同时间段相比差异均无统计学意义(均P>0.05)。结论:体外分离培养纯化的淋巴细胞在局部应用于神经损伤处对面神经再生修复可起一定的促进作用。  相似文献   
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