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91.
The study aimed to compare the longitudinal assessment of autonomic nerve function by computerized infrared pupillometry and standard cardiovascular tests in adolescents with diabetes. Adolescents (n = 150) were assessed at two time points (T1 and T2). The median time interval between assessments was 1.5 (range 0.9–3) years. At T1 the median age was 14.5 (range 8.3–19.5) years and the median duration was 6.5 (range 1.1–16) years. The pupillary variables assessed included the resting pupil diameter, the maximum constriction velocity, and the reflex amplitude of constriction. Heart rate reflexes were assessed in response to deep breathing, the Valsalva manoeuvre, and on standing from a lying position (30/15 ratio). Between visits there was a significant decrease in maximum constriction velocity (6.0 mm s?1 vs 6.3 mm s?1, p = 0.0001) and resting pupil diameter (6.2 mm vs 6.3 mm, p = 0.001). At reassessment pupillary abnormalities increased from 32 (21 %) to 45 (30%), with 17 (54 %) of the initial abnormalities persisting. Adolescents with abnormally slow maximum constriction velocity compared to those with normal maximum constriction velocity had a higher glycated haemoglobin (HbA1c%) at T2 (p = 0.02) and between assessments (p = 0.01). Cardiovascular test abnormalities did not increase between visits and the persistence of initial abnormalities was low (21 %). In summary, pupillometry appears a more sensitive test of autonomic nerve dysfunction in adolescents with diabetes than assessment of cardiovascular reflexes.  相似文献   
92.
Lyme disease is a cause of illness involving multiple organ systems, including, in 10–15 % of cases, the nervous system. Peripheral radiculoneuritis, cranial neuritis, encephalitis and myelitis are among the neurological manifestations found in the second and third stages. We present the MRI findings in isolated oculomotor nerve involvement by Lyme disease and discuss the differential diagnosis. Received: 14 June 1995 Accepted: 16 January 1996  相似文献   
93.
狗脊髓截除自体隐神经大网膜移植的初步观察   总被引:3,自引:0,他引:3  
实验用6只狗于T13处切除脊髓8mm,局部用隐神经、大网膜移植。对照组6只狗单纯切除脊髓8mm。术后3个月、6个月实验组动物全部恢复到C/Ⅲ级功能,组织学切片见移植神经有不同程度存活,可记录到股四头肌、胫前肌电位。对照组动物仅达到0/0~A/I织功能,组织学切片见脊髓缺损处为结缔组织,诱电位波形消失。分析了影响脊髓神经功能恢复的原因。  相似文献   
94.
神经移位修复臂丛神经根性撕脱伤   总被引:3,自引:2,他引:1  
1987年7月~1994年6月,对21例臂丛神经根性撕脱伤采用神经移位修复。其中复合移位4组神经(膈神经、副神经、颈丛运动支、肋间神经)者1例,3组(膈神经、副神经、颈丛运动支)者6例,2组(膈神经、副神经)者9例,1组(膈神经或颈丛运动支或肋间神经)者5例。术中发现臂丛神经变异1例,对4例合并锁骨下动脉损伤者,在神经移位的同时进行血管修复,促进患肢的血液循环,有利于神经的康复。随访到19例,随访时间为8个月~6年2个月,优良率达73.7%。认为,神经移位术是修复神经根性撕裂伤的常规方法,合并血管损伤者也应同时修复,对促进神经功能恢复有利  相似文献   
95.
54只大白鼠随机分三组,用不同方法修复坐骨神经缺损,术后60天和90天取材,作电生理、组织学和电镜观察的比较,结果表明:游离神经移植+血管植入方法和带血管蒂神经移植效果同样好,二者均显著优于单纯游离神经移植。  相似文献   
96.
本工作观察了乙酰胆硷(Ach)和电刺激迷走神经对0.6N HCl引起的胃粘膜出血性损伤的保护作用,发现皮下注射50μg/kg的氯化Ach和电刺激膈下迷走神经5min,可明显降低HCl引起的胃粘膜出血量,这一作用可被消炎痛及阿托品所阻断。提示这种保护作用是通过依赖于M-受体的内源性前列腺素。  相似文献   
97.
Summary Nerve regeneration was studied in a model of centrocentral anastomosis (CCA) performed on the sciatic nerve of the rat. Experimental CCA was made by suturing the proximal end of the peroneal branch on the proximal end of the sural branch, placing between them a peroneal nerve graft (Group I, 20 rats) or a silicone chamber (Group II, 12 rats). Nerve grafts had a length of 5mm and silicone chambers 7 mm. In six silicone chambers an 1 mm nerve graft was placed in the centre of the tube. In group I animals anterograde degeneration was studied by cutting the graft 60 days after surgery. In group II, nerve regeneration was studied 2, 4 and 8 weeks after surgery. Results indicate that in CCA: 1) regenerated axons coming from one nerve end grow into the graft but do not cross the contralateral suture line; 2) regeneration is poorer in silicone chambers than in nerve grafts; and, 3) in silicone chambers regeneration is related to time. The reduction in the regenerative capability in CCA seems to be related to the alteration of nerve sprouts aiming for the peripheral targets.  相似文献   
98.
雪旺细胞源运动神经营养蛋白对周围神经再生的影响   总被引:3,自引:0,他引:3  
目的:研究雪旺细胞源运动神经营养蛋白对周围神经再生的影响。方法:60只SD大鼠均分为3组,A和B组分别在桥接于大鼠右侧坐骨神经断端之间的硅胶管内加入26KD和50KD的雪旺细胞源运动神经营养蛋白,C组加PBS液作为对照。术后1~6月每隔半月测定实验侧坐骨神经功能指数,术后3月测定实验侧坐骨神经的电生理和形态学指标。结果:A和B组实验侧坐骨神经的功能指数、电生理和形态学指标与C组比较,差别有非常显著性。结论:26KD和50KD雪旺细胞源运动神经营养蛋白对周围神经再生有促进作用。  相似文献   
99.
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   
100.
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   
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