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71.
探刊干性型老年黄斑变性(age-related macular deganeration,AMD)的病变发展特征并 寻找监测AMD病情进展的较敏感指标。
方法:用眼底彩色照相和眼底荧光血管造影(FFA)、明视视网膜电囤(ERG)、FM100-hue 色彩试验及视力检查,对60例(111眼)50~80岁、视力≤1.0的干性型AMD患者进行3~74个月(平均30.2个月)的随访观察。
结果:本组68眼经FFA检查、平均25.6个月随访,其中25%的患眼病灶损害有快慢不一的发展.全部111眼视力在平均30.2个月随访中有18%患眼的视力下降2行以下,且与病灶进展相符,FM100-hue 色彩试验的被随访者中,随访2年以后,其总错误分明显的增加(P<0.01).63眼的明视ERG在随访过程中无明显变化。
结论:大部分干性AMD患眼的病灶损害和视力可以在较长时间内维持稳定。FM100—hue的总错误分可能为监测AMD病情进展的较敏感指标.
(中华眼底病杂志,1997,13:150-152) 相似文献
72.
采用现代影像学、电生理学、神经化学和免疫学技术等综合方法,对353例隐原性癫痫的病因进行了研究.研究结果,120例行颅脑CT检查,发现可导致癫痫发作的各种器质性病变35例,占29.17%.81例行体感诱发电位(SEP)与听觉诱发电位(AEP)检查,发现SEP和AEP异常分别为27例,占33.33%.分别对24例行脑脊液3-甲氧基-4-羟基苯乙二醇(MHBG)、5-羟吲哚乙酸(5-HIAA)和高香草酸(HVA)高效液相色谱分析,发现MHBG、5-HIAA和HVA三项指标都有显著改变.100例行血清免疫球蛋白、补体C_3、E玫瑰花环形成率和淋巴细胞转化率检查,结果均有明显改变.脑组织的器质性病变提示隐原性癫痫有其发病的组织学基础.脑诱发电位异常提示脑生物电活动的功能改变,它可由CT所见或难以分辨的脑组织病变所致,也可由局部脑组织代谢障碍所致.MHBG、5-HIAA和HVA的改变提示该病的发作与脑内单胺类神经递质有关.补体C_3的升高,提示该病的发作与补体介导的免疫反应有关. 相似文献
73.
74.
We studied the effects of Wallerian degeneration in the cerebral peduncle shown by magnetic resonance imaging (MRI) following a supratentorial vascular lesion, to identify the somatotopic localisation of the descending cortical tracts. Patients with a lesion involving a large area of a cerebral hemisphere had an area of abnormal signal intensity in the whole cerebral peduncle, suggesting Wallerian degeneration of all the whole descending cortical tracts. With a small lesion confined to the precentral gyrus, corona radiata, or posterior limb of the internal capsule there was an abnormal signal at the centre of the peduncle, suggesting degeneration of the precentrospinal tract. Those with a small lesion confined to the paracentral gyrus had an abnormal area slightly lateral to the centre of the peduncle, suggesting degeneration of the parietospinal tract. Patients with a lesion of the parietal or temporal lobes, not including the paracentral or precentral gyri, corona radiata, or the posterior limb of the internal capsule, had an abnormal area laterally in the peduncle, suggesting degeneration of the parietopontine or temporopontine tract. 相似文献
75.
儿童胫后神经刺激的体感诱发电位正常值及其特点 总被引:4,自引:0,他引:4
探讨儿童体感诱发电位的正常值。对30例8-14岁健康儿童记录和测量了刺激胫扣神经引起的脊髓和皮层SEPs正常值,并计算出胫后神经4 传导速度。结果1.SEPS各波潜伏期与身高均呈高度正线怀相关,与年龄,体重亦呈正相关,而潜伏期与年龄,体重的正相关是由身高引起的。2.P40-N20波间期与身高,年龄,体重均无显著相关关系。结论,SEPS潜伏期正常值应按其与身高的回归方程确定,P40-N20波间期正常 相似文献
76.
Abstract The aim was to measure the effect of gastric electrical stimulation on the frequency of canine antral pacesetter potentials (PPs), the strength of antral contractions, and the rate of gastric emptying while fasting, after feeding and with pentagastrin stimulation. Four conscious dogs with a stimulating electrode placed 10 cm proximal to the pylorus and recording electrodes and strain gauges placed 7, 5 and 3 cm proximal to the pylorus underwent myoelectric and strain gauge recordings while fasting, after feeding (250 ml 5% dextrose labelled with polyethylene glycol), and during pentagastrin infusion (0.5 μg kg?1 min?1) on four separate days. On each day, electrical stimulation was done using one of four stimulation frequencies (0, 6, 30 and 1200 stimuli per minute ***[s.p.m.]). Stimulation at 6 and 30 s.p.m. increased the fasting and fed PP frequency, whereas 1200 s.p.m. stimulation did not. Feeding decreased the maximum driven frequency, and pentagastrin increased it. Neither the motility index nor the gastric emptying rate were consistently changed by stimulation at any frequency. In conclusion, canine proximal antral stimulation at 6 and 30 s.p.m. sped PP frequency during fasting and after feeding, but stimulation over a wide range of frequencies had little effect on gastric contractions and emptying. 相似文献
77.
P. Praamstra A. R. Cools D. F. Stegeman M. W. I. M. Horstink 《Journal of the neurological sciences》1996,140(1-2):67-74
Movement-related potentials were recorded preceding self-paced voluntary movements in patients with Parkinson's disease and in healthy subjects of the same age group. We compared the Readiness Potential preceding joystick movements in a fixed direction and preceding joystick movements in freely selected directions. In normal subjects the Readiness Potential amplitude was higher preceding freely selected movements than preceding movements in a fixed direction. The Readiness Potential in Parkinson patients failed to be modified by the different modes of movement selection. The modulation of the Readiness Potential by different ways of preparing for movement might be due to the supplementary motor area (SMA) being more strongly engaged by tasks requiring internal control of movements than by tasks that are externally structured. The results suggest that this task-dependent variation of SMA activity is reduced in Parkinson's disease. A failing capacity to adapt SMA activity to different task demands has previously been suggested by evidence from positron emission tomography studies using similar tasks. 相似文献
78.
79.
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
80.
S. C. Phillips 《Acta neuropathologica》1987,73(2):171-176
Summary Groups of adult male mice were either fed a thiamine-deficient diet for 10 weeks and thereafter treated with ethanol by making them inhale vapourized cane spirit for 10 weeks, or given both treatments simultaneously. The brains of these mice were then searched for degeneration using both light and electron microscopy. No degenerating nerve cells were observed in any animal in the cerebral cortex, hippocampus, cerebellum, olfactory bulbs, midbrain or hindbrain. However, axon terminal degeneration was seen in the olfactory bulbs and deep cerebellar nuclei in mice given the combined treatment. No cerebellar degeneration was found and only little degeneration was present in the olfactory bulbs of mice given the two treatments at different times. Thus, the combined treatment of alcohol and thiamine deficiency produced more brain damage than the sum of that produced by the two treatments given separately. This represents the first experimental in vivo demonstration of a biochemical interaction between these two factors in alcohol-related brain damage. The findings of long-term animal treatment with models using thiamine antagonists are compared.Supported by the special Research Fund Programme of Monash University (Post-Doctoral Fellowship) 相似文献