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81.
神经根慢性嵌压损伤的动物模型建立 总被引:3,自引:0,他引:3
目的:建立一种由自身骨性增生造成神经根慢性嵌压损伤的动物模型,为相关实验提供造模方法一方法:30只健康家猫,手术显露右侧C7、C8和L5、L6冲经根及其椎问孔内口,用牙髓钻破坏椎间孔周围骨皮质后,将“V”形松质骨块沿骨壁嵌于神经根通道的骨性管道内及侧隐窝后方,左侧做正常对照。在造模术前和术后第2、4、8、12、24周行磁刺激运动诱发电位(MEP)检测,每次随机选6只,4~5只行影像学检查,以确定神经根通道的狭窄程度和神经根受压状态,6只均做病理组织学检查和椎间孔截面积测量。结果:术后早期实验侧肢体出现行为异常:而后有不同程度肌萎缩;后期部分肢体远端出现溃疡。影像学检查随着嵌压时间延长.实验侧椎间孔骨痂增多,狭窄加重。神经根受压变形,椎间孔骨性截面积8周后明显减小,与对照侧比较有显著性差异。术后2周,神经根组织学检查主要表现为神经束膜、内膜的水肿。髓鞘肿胀;4周后发生节段性脱髓鞘:8周时神经轴突增粗、断裂,远端瓦勒氏变性;12周后变性冲经结构崩解、吸收,形成空洞:24周时整个神经干纤维化。术后4周时实验侧MEP开始出现潜伏期延长;8周时伴有波形分化不清;12周波幅明显下降:24周MEP的引出困难,部分电位消失。结论:采用椎问孔内自体松质骨植入,造成神经根慢性嵌压性损伤模型成功率高,操作简单,适用于脊柱各个节段,其损伤部位和形式与临床更为接近。 相似文献
82.
孙保祥 《山东医大基础医学院学报》2004,18(6):342-343
目的:探讨口腔径路曲安奈德蝶腭神经节封闭治疗变应性鼻炎的效果。方法:变应性鼻炎患者415例,男270例,女145例。用自制封闭针头于口腔径路行曲安奈德蝶腭神经节封闭术。结果:415例中,有效250例,好转63例,总有效率为99.5%。结论:经口腔径路用曲安奈德行蝶腭神经节封闭术是治疗变应性鼻炎的有效疗法。 相似文献
83.
[目的]观察器械侧向压力(load)和根管锉的工作磨损(wear)对超声锉和声波锉切削效力的影响。[方法]在0.245 N或0.490 N侧向压力下,使用新或已经使用1 min的根管锉,利用本院自制的根管器械切削效力测试仪观察声波和超声波根管器械对牛骨片的切削能力。[结果]声波根管器械平均较超声波根管器械切削效力高292%,差异具有统计学意义(P<0.01);侧向压力和锉的磨损对声波根管器械切削效力的影响较超声波器械更明显(P<0.01)。[结论]同超声波器械相比,声波根管器械可能具有更高的临床工作效率,但器械容易磨损;临床使用中应谨慎控制声波根管器械侧向压力的大小,防止根管过度切削。 相似文献
84.
目的 探讨星状神经节阻滞 (stellate ganglion block,SGB)加服药物对偏头痛的治疗作用。方法 2 4 0例偏头痛患者按就诊顺序分为观察组与对照组 ,观察组接受 SGB治疗的同时 ,口服尼莫地平等药物。结果 观察组有效率达89.2 % ,高于对照组 (P<0 .0 5 ) ,其中治疗后完全无痛的病例 5 1.7% ,高于对照组 (P<0 .0 1) ,观察发现病程对于 SGB治疗偏头痛疗效影响较大 (P<0 .0 5 )。结论 SGB加服药物治疗偏头痛具有操作简单 ,起效快 ,疗效确切 ,副作用少等优点 ,值得临床推广应用。 相似文献
85.
Activity labeling was applied to the olfactory systems of the terrestrial slug Limax valentianus using 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG), a fluorescent derivative of glucose. 2-NBDG was incorporated into cultured Limax olfactory interneurons, and this was partially blocked by the presence of a high concentration of glucose in the medium, indicating that a part of the uptake of 2-NBDG is mediated by glucose transporters. Next, in order to map odor-related neuronal activity in the primary olfactory center, tentacular ganglion, we injected 2-NBDG into the body cavities of slugs and exposed them to odors or clean air (control). In the odor-stimulated animals, the cell mass region was strongly stained. The digit-like extensions and the neuropil region were also stained in some animals. The control animals showed no staining. The neurons in the cell mass are thought to be involved in generating oscillating activities in the tentacular ganglion, and their activation may imply modulation of oscillatory activity during odor processing. Our results show that 2-NBDG is useful for mapping neuronal activity in vivo. 相似文献
86.
脊神经节神经元周围突至肾及体壁的分支投射 总被引:1,自引:0,他引:1
实验将快蓝(FB)和核黄(NY)分别注入大鼠左肾纤维膜下及左体壁神经干内,结果在荧光镜下发现左T_(9-13),L1脊神经后根节(DRG)内存在双标记细胞,提示大鼠T_(9-13),L1段DRG内的部分神经元的周围突分支支配肾及体壁,为肾绞痛所致牵涉痛的解释,提供了神经解剖学基础。 相似文献
87.
The antimicrobial effects of a saturated calcium hydroxide solution, and in combination with 10% and 20% detergent, were evaluated on Streptococcus faecalis. Strepto-coccus sanguis, Streptococcus mutans, Streptococcus salivarius, Neisseria sp., diphlheroid, Staphylococcus aureus, Lactobacillus sp., Staphylococcus epidermidis, Bacillus suhtilis and Candida albicans. The saturated calcium hydroxide solution was effective against only four of the 11 microorganisms studied over a 60-min exposure time. The calcium hydroxide solutions con-taining detergent killed all 11 test organisms over a 30-min exposure time. This difference was statistically significant (P<0.01). No statistically significant difference in antimicrobial action was found between the 10% and 20% detergent calcium hydroxide solutions (F>0.01). However, the low surface tension (46.5 × 10?3 Nm?1) and high pH (10.8) of the calcium hydroxide solution with 20% detergent establish it as the more effective solution. 相似文献
88.
从34例牙髓根管感染中共分离出厌氧菌118株,经菌属分类依次为消化链球菌属,拟杆菌属,梭杆菌属,放线菌属,韦荣氏球菌属和珠网菌属,其中前3属为77株,分离率为65.3%,这一结果显示该3属细菌与极管感染有密切关系,是牙髓根管感染的优势菌。 相似文献
89.
The present investigation introduces an in vitro model to study macrophage properties during demyelination. Rat dorsal root ganglia (DRG) were cultured for obtaining myelinated peripheral nerve fibers. These cultures were exposed to non-resident macrophages. In untreated control cultures, there was no indication of myelin removal by the added macrophages. DRG were exposed to enzymatically generated oxygen radicals using the xanthin/xanthin oxidase or the glucose/glucose oxidase system. Assessment of Schwann cell viability and ultrastructural morphology revealed different patterns of cell cytotoxicity and morphological changes in different experiments. High concentrations caused complete tissue necrosis of the DRG, while low concentrations did not affect either cell viability or ultrastructural morphology. Under intermediate experimental conditions, oxygen radicals caused non-lethal Schwann cell damage leading to Schwann cell retraction and myelin sheath rejection. Myelin lamellae were disrupted and decompacted. These changes were followed by a selective macrophage attack on myelin sheats, resulting in demyelination. Axons, Schwann cells and sensory ganglion cells survived this attack. The specificity of the oxygen radical effects was tested in experiments using the oxygen radical scavengers catalase and superoxide dismutase. Catalase prevented the described effects on cell morphology and subsequently blocked demyelination by non-resident macrophages.Supported by a grant from the Deutsche Forschungsgemeinschaft (DFG) (Br 1274/1-1) 相似文献
90.
The superior sagittal sinus (SSS) and the trigeminal ganglion (Vg) of anesthetized cats were stimulated electrically and field potentials in the upper cervical spinal cord and regional cerebral blood flow were recorded. Stimulation of the entire ganglion produced smaller field potential changes in two regions (medioventral area (MVA); dorsolateral area (DLA] of the upper spinal cord than did stimulation of the sagittal sinus (Vg/SSS response ratio = 17% for the MVA and 48% for the DLA). Stimulation of the trigeminal ganglion increased blood flow in only the frontal and parietal cortices (+93% and +33%), whereas stimulation of the sinus produced both larger changes in these areas (+137% and +139%) and also produced changes in regional cerebral blood flow in the thalamus (+122%). 相似文献