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61.
We report on 3 sibs (2 males and one female) with sensorineural deafness. The presence of ovarian dysgenesis in the girl suggested a diagnosis of Perrault syndrome. In addition our patients have a sensory polyneuropathy and amelogenesis imperfecta. Two of the patients have mild mental retardation, fine choreatic movements, and dyspraxia. It is discussed whether these findings are part of a separate clinical entity or should be included within the spectrum of the Perrault syndrome. © 1994 Wiley-Liss, Inc.  相似文献   
62.
 Peripheral nerve biopsy is now an established, valuable investigative procedure, but as it can give rise to significant residual symptoms it should only be undertaken after careful consideration of the indications and with informed consent from the patient. Nerve biopsies should only be processed and evaluated in a laboratory with the relevant particular expertise. It is generally recommended that a sural nerve biopsy be performed in combination with a muscle biopsy but not vice versa (muscle biopsies together with a nerve biopsy). Nerve biopsy is not the only means of sampling peripheral nerve tissue to study the peripheral nervous system. Examination of the innervation of the skin may be informative. The same is likely to be true for motor point muscle biopsy. Nerve biopsy is mainly used for morphology although molecular genetic techniques using fresh or archival nerve biopsies are increasingly available. Chemical analysis is undertaken mainly for research purposes. Received: 10 June 1997 / Accepted: 29 October 1997  相似文献   
63.
A series of substances (designated CTQ compounds) with a guanidine group have been synthesized and tested for their ability to promote neuronal survival and neurite outgrowth. Mouse neuroblastoma clonal cell lines grown in serum-containing medium for 10 days as well as primary cultures of embryonic chicken ganglion neurons grown in serum-free defined medium for 1 or 2 days have been used for the experiments. Among the various CTQ compounds (CTQ1–CTQ20) tested, only CTQ8 exerted positive neurotrophic effects on these peripheral neuronal cells. At a concentration of 10−4 M, CTQ8 enhanced neuritogenesis of neuroblastoma cells. However, the most striking influence of CTQ8 was its promoting effect (6- to 10-fold) on the survival of chicken ciliary and dorsal root ganglionic neurons at concentrations ranging from 10−3 M to 5×10−4 M.  相似文献   
64.
Summary Morphological change of endoneurial and perineurial vessels accompanied severe loss of myelinated axons in peripheral nerves of each of 17 patients with diabetic neuropathy. Vascular mural thickening averaged 18.9±9.9 m2 in diabetic capillaries (n=11) vs. 6.9±4.1 m2 in controls (n=7). Electron microscopy revealed vigorous endothelial proliferation as well as thickening and reduplication of basal lamina in each instance. Particular attention was paid to vessels which penetrate the perineurium en route to the endoneurial intertitium, since they provide a major portion of the endoneurial blood supply. Luminal narrowing and mural thickening of these vessels was compounded by basal laminar thickening of the perineurium. Fenestrated endoneurial capillary endothelium was noted in one case. Both demyelination and axonal degeneration were observed with intra-axonal glycogen accumulation in some axons. Morphometric analysis revealed extensive myelinated nerve fiber loss in diabetic nerves. These morphological findings emphasize the impact of diabetic microangiopathy on specialized endothelium and suggest that local anatomic factors in the perineurial sheath render the nerve vulnerable to chronic ischemia.Supported in part by the National Institute for Communicative Disorders and Stroke NS-14162 and by the Veterans Administration Research Service  相似文献   
65.
Summary Two cases of trigeminal neuropathy with tissue loss are described, one in a Spillane-Wells syndrome, the other in a Riley-Day syndrome. Although the etiology was different, nose-picking led in both cases to a typical punchedout lesion of the skin and cartilage of nose tip, columella and alae nasi. Reconstruction was performed only in the first case, after resolution of the neuropathy. Reconstruction should not be considered for cases with persistant anaesthesia.Head: M. Lejour  相似文献   
66.
Aim: To investigate the effect of normalizing vitamin B12 (B12) levels with oral B12 (methylcobalamin) 1000 μg/day for one year in patients with diabetic neuropathy (DN). Patients and methods: In this prospective, double-blind, placebo-controlled trial, 90 patients with type 2 diabetes on metformin for at least four years and both peripheral and autonomic DN were randomized to an active treatment group (n = 44) receiving B12 and a control group (n = 46) receiving a placebo. All patients had B12 levels less than 400 pmol/L. Subjects underwent measurements of sural nerve conduction velocity (SNCV), sural nerve action potential (amplitude) (SNAP), and vibration perception threshold (VPT), and they performed cardiovascular autonomic reflex tests (CARTs: mean circular resultant (MCR), Valsalva test, postural index, and orthostatic hypotension). Sudomotor function was assessed with the SUDOSCAN that measures electrochemical skin conductance in hands and feet (ESCH and ESCF, respectively). We also used the Michigan Neuropathy Screening Instrument Questionnaire and Examination (MNSIQ and MNSIE, respectively) and questionnaires to evaluate quality of life (QoL) and level of pain (pain score). Results: B12 levels increased from 232.0 ± 71.8 at baseline to 776.7 ± 242.3 pmol/L at follow-up, p < 0.0001, in the active group but not in the control group. VPT, MNSIQ, QoL, pain score, SNCV, SNAP, and ESCF significantly improved in the active group (p < 0.001, p = 0.002, p < 0.0001, p < 0.000, p < 0.0001, p < 0.0001, and p = 0.014, respectively), whereas CARTS and MNSIE improved but not significantly. MCR, MNSIQ, SNCV, SNAP, and pain score significantly deteriorated in the control group (p = 0.025, p = 0.017, p = 0.045, p < 0.0001, and p < 0.0001, respectively). Conclusions: The treatment of patients with DN with 1 mg of oral methylcobalamin for twelve months increased plasma B12 levels and improved all neurophysiological parameters, sudomotor function, pain score, and QoL, but it did not improve CARTS and MNSIE.  相似文献   
67.
显微外科技术治疗周围神经嵌压症   总被引:2,自引:0,他引:2  
目的 :为探讨显微外科技术治疗周围神经嵌压症的疗效。方法 :采用显微外科技术对各部位周围神经嵌压症 2 5例进行神经内外松解术。结果 :2 5例周围神经嵌压症患者术后症状、体征及肌电图检查均较术前明显改善 ,疗效满意。结论 :显微外科技术是治疗周围神经嵌压症的一种有效方法。  相似文献   
68.
目的 探讨银杏黄酮甙和甲基B12 对糖尿病周围病变的治疗效果。方法 将 14 9例糖尿病周围神经病变患者随机分为 4组 ,分别为常规治疗组 (对照组 )、银杏黄酮甙组 (第 1组 )、甲基B12 组 (第 2组 )、银杏黄酮甙与甲基B12 联合组(第 3组 )。疗程为 8周。观察治疗前后自觉症状、腱反射和神经传导速度。结果 第 3组总有效率为 95 % ,显著高于对照组 (17% ) (P <0 .0 0 5 )。第 1组和第 2组 ,总有效率分别为 6 9%和 72 % ,与对照组比较均有显著差异 (P <0 .0 1)。第 3组神经传导速度治疗后较冶疗前显著改善 (P <0 .0 1) ,而且显著优于对照组 (P <0 .0 1)、第 1组 (P <0 .0 5 )和第 2组 (P <0 .0 5 )。结论 银杏黄酮甙和甲基B12 联合治疗糖尿病周围神经病变较单独应用更为有效。  相似文献   
69.
目的:探究桃红四物汤对糖尿病周围神经病变(DPN)大鼠炎症反应及对Toll样受体4(TLR4)/髓样分化因子88(MyD88)/核转录因子kappan B(NF-κB)通路的影响。方法:从45只SD大鼠中随机选取10只为对照组,其余35只大鼠建立DPN模型,3只大鼠建模失败,其余随机分为模型组,桃红四物汤低、高剂量组及α-硫辛酸组,每组各8只。桃红四物汤低、高剂量组分别给予4.5、18 g/(kg·d)的桃红四物汤,α-硫辛酸组给予α-硫辛酸20 mg/(kg·d),对照组及模型组给予等量的0.9%氯化钠溶液,均灌胃给药。连续给药8周后,检测大鼠血清炎症因子、血糖及血脂指标及神经传导情况,观察坐骨神经病理学变化,检测TLR4相关通路蛋白表达情况。结果:与对照组比较,模型组血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)及白细胞介素-6(IL-6)水平升高,血糖、糖化血红蛋白(HbA1c)、甘油三酯(TG)及血清总胆固醇(TC)水平升高,感觉神经传导速度(SNCV)及运动神经传导速度(MNCV)水平降低,TLR4、MyD88、NF-κB蛋白表达上调(P<0.05)...  相似文献   
70.
A 40-year-old woman presented with progressive lower leg pain and spontaneous toe movement. The EMG showed a posterior tibial nerve mononeuropathy and continuous myokymic discharges in posterior tibial-innervated muscles. The MRI revealed a markedly enlarged posterior tibial nerve. Toe movements and myokymia were unaffected by the proximal transection of the lesion but ceased abruptly when the distal end of the fusiform "tumor" was resected, suggesting that spontaneous electrical foci may have been located along the nerve lesion. The markedly enlarged nerve segment contained edematous, swollen fascicles with marked Schwann cell onion-bulb lesions and angiocentric, lymphocytic, and lymphofollicular infiltration. This nerve lesion is an example of a newly recognized entity called hypertrophic mononeuritis.  相似文献   
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