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991.
目的:研究伪随机复合频率旋转电磁场的驱、灭鼠效果。方法:将60只成年KM种小白鼠(雌雄各半)随机分成散养辐射组A、圈养辐射组B和对照组C。散养辐射组A放置在一半有电磁场辐射、一半没有电磁场辐射的大空间环境中,并提供一定的活动空间;圈养辐射组B放置在有伪随机复合频率旋转电磁场辐射的环境中,24h受电磁场辐射;对照组安排在无辐射区,饲养环境与辐射组B相同。在辐射期间观察小鼠的精神状态和行为活动,持续90天;第91天处死所有小鼠,提取内脏器官和生殖系统组织(包括雌鼠的卵巢和子宫,雄鼠的睾丸和附睾),制成组织切片,利用电子显微镜获取所需图片并对其进行图像处理和数据分析;对小鼠体重变化、行为活动、雄鼠睾丸曲精小管细胞个数及面积进行统计分析。结果:A组小鼠进食尽量远离辐射区;B组小鼠的精神状态较对照C组萎靡,追逐交配行为减少,活动率降低,体重变化差异显著,睾丸曲精小管中细胞个数及面积显著低于对照组(细胞个数:19.17±4.20 VS 44.92±23.60,面积:3497.17±756.84 VS 5026.50±1057.72,P〈0.01)。结论:伪随机复合频率旋转电磁场有明显的驱、灭鼠效果。  相似文献   
992.
We studied three patients who developed left unilateral punctate keratitis after suffering left-sided Wallenberg Syndrome. A complex evolution occurred in two of them. In all cases, neurophysiological studies showed damage in the trigeminal sensory component at the bulbar level. Corneal involvement secondary to Wallenberg syndrome is a rare cause of unilateral superficial punctate keratitis. The loss of corneal sensitivity caused by trigeminal neuropathy leads to epithelial erosions that are frequently unobserved by the patient, resulting in a high risk of corneal-ulcer development with the possibility of superinfection. Neurophysiological studies can help to locate the anatomical level of damage at the ophthalmic branch of the trigeminal nerve, confirming the suspected etiology of stroke, and demonstrating that prior vascular involvement coincides with the location of trigeminal nerve damage. In some of these patients, oculofacial pain is a distinctive feature.  相似文献   
993.
目的初步探讨尺神经前移在肱骨远端髁间骨折治疗中的手术方法及效果。方法 29例C型肱骨髁间骨折患者切开复位内固定后全部进行尺神经预见性前移。结果 29例随访患者中追踪8~38个月,平均18个月,术后2~4个月骨折全部愈合。按照Mayo肘关节功能评分标准,优良率79.3%,尺神经功能情况根据Asami评价标准,优19例(65.5%),良7例(24.1%),一般2例(6.9%),差1例(3.4%),其中3例功能不满意者均为术前既有尺神经损伤症状。结论尺神经前移可作为肱骨远端髁间型骨折手术治疗中的常规治疗方法,可有效避免尺神经麻痹现象发生。  相似文献   
994.
Although most of nerve injuries associated with Monteggia fracture-dislocation in children are neurapraxias and will recover spontaneously after conservative treatment,surgical exploration of the invol...  相似文献   
995.
Neurons choose growth pathways with half hearted reluctance, behavior that may be appropriate to maintain fixed long lasting connections but not to regenerate them. We now recognize that intrinsic brakes on regrowth are widely expressed in these hesitant neurons and include classical tumor suppressor molecules. Here, we review how two brakes, PTEN (phosphatase and tensin homolog deleted on chromosome 10) and retinoblastoma emerge as new and exciting knockdown targets to enhance neuron plasticity and improve outcome from damage or disease.  相似文献   
996.
目的比较不同神经吻合方式修复双侧指固有神经缺损的临床疗效。方法选择70例双侧指固有神经缺损患者按照不同神经吻合方式分成A、B、C 3组:A组24例采用移植神经弓端侧吻合,B组26例采用移植神经弓双端侧吻合,C组20例采用移植神经直接桥接端端吻合。观察3组指关节自主活动度总和(TAM)、感觉恢复情况、两点辨别觉和不良反应发生情况。结果患者均获得随访,时间1~10个月。3组指关节TAM优良率比较差异无统计学意义(P0.05)。A组和B组远节指腹感觉明显高于C组(P0.05),A、B两组比较差异无统计学意义(P0.05)。A组和B组两点辨别觉明显低于C组(P0.05),A、B两组比较差异无统计学意义(P0.05)。3组患者伤口均甲级愈合,未出现伤口感染和皮肤软组织坏死。术后72 h出现血管危象A组1例、B组2例、C组1例,均在肌肉注射盐酸哌替啶+静脉滴注肝素钠后缓解。B组2例术后4~6周用力握物时出现麻木和放射性疼痛等,术后6~12周疼痛自行消失。结论移植神经弓端侧吻合能够有效修复双侧指固有神经缺损,促进指腹感觉的恢复,效果优于移植神经直接桥接端端吻合。  相似文献   
997.
Neurosarcoidosis is seen in 5–15% of patients with systemic sarcoidosis. The most common cranial nerve presentations are optic neuropathy and facial nerve palsy. The authors present a case of sarcoidosis presenting with a pupil-involving third nerve palsy. The patient responded to corticosteroid therapy with resolution of investigations her cranial nerve palsy but progressed to develop cerebellar signs. This is the first documented case of a pupil-involving third nerve palsy occurring as the first presentation of neurosarcoidosis. Although typically a pupil-involving third nerve palsy necessitates urgent neuroimaging to rule out a posterior communicating artery aneurysm, it is important to recognise inflammatory causes in the differential diagnosis.  相似文献   
998.
In this study, we established a rat model of optic nerve crush to explore the effects of erythropoietin on retinal ganglion cell axonal regeneration. At 15 days after injury in erythropoietin treated rats, retinal ganglion cell densities in regions corresponding to the 1/6, 3/6 and 5/6 ratios of the retinal radius were significantly increased. In addition, the number of growth associated protein-43 positive axons was significantly increased at different distances (50, 250 and 500 ?m) from the crush site after erythropoietin treatment. Erythropoietin significantly increased growth associated protein-43 protein levels in the retina after crush injury, as determined by western blot and immunofluorescence analysis. These results demonstrate that erythropoietin protects injured retinal ganglion cells and promotes axonal regeneration.  相似文献   
999.
Previous studies have demonstrated that doublecortin-positive immature neurons exist pre- dominantly in the superficial layer of the cerebral cortex of adult mammals such as guinea pigs, and these neurons exhibit very weak properties of self-proliferation during adulthood under physiological conditions. To verify whether environmental enrichment has an impact on the proliferation and maturation of these immature neurons in the prefrontal cortex of adult guinea pigs, healthy adult guinea pigs were subjected to short-term environmental enrichment. Animals were allowed to play with various cognitive and physical stimulating objects over a period of 2 weeks, twice per day, for 60 minutes each. Immunofluorescence staining results indicated that the number of doublecortin-positive cells in layer II of the prefrontal cortex was significantly increased after short-term environmental enrichment exposure. In addition, these doublecortin-positive cells co-expressed 5-bromo-2-deoxyuridine (a marker of cell prolifera- tion), c-Fos (a marker of cell viability) and NeuN (a marker of mature neurons). Experimental findings showed that short-term environmental enrichment can induce proliferation, activation and maturation of doublecortin-positive cells in layer II of the prefrontal cortex of adult guinea pigs.  相似文献   
1000.
The authors describe the correlation between 3-Tesla magnetic resonance neurography (MRN) and surgical findings in two patients who underwent multiple previous failed ulnar nerve surgeries. MRN correctly localized the site of the abnormality. Prospectively observed MRN findings of perineural fibrosis, ulnar nerve re-entrapment abnormalities, medial antebrachial cutaneous neuroma and additional median nerve entrapment were confirmed surgically.  相似文献   
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