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141.
重组人神经营养因子-4/5蛋白抗三氧化二砷神经毒作用 总被引:5,自引:0,他引:5
目的初步观察重组人神经营养因子-4/5(hNT-4/5)蛋白对三氧化二砷毒性的抑制作用。方法利用hNT-4/5蛋白具有抗神经毒性的特点,采用本实验室克隆表达及部分纯化的具有天然hNT-4/5蛋白生物学活性的重组hNT-4/5蛋白,以不同水平的重组hNT4/5蛋白(0-100μl)与不同浓度的As2O3(0-160μmol/L)同时加入各组鸡胚前脑神经细胞和PC12细胞培养液中共同孵育24-48小时,观察其对染毒鸡胚前脑神经细胞存活和PC12细胞突起生长的影响作用。结果在鸡胚前脑神经细胞和PC12细胞中与As2O3共同培养48小时后,对照组与实验组的细胞存活率差异有显著性,而且细胞存活率和突起数目随hNT-4/5浓度增高而提高和增加。结论初步观察到重组hNT4/5蛋白具有抑制As2O3的毒性作用,为从基因工程途径寻找抗环境毒物因子提供了依据。 相似文献
142.
Dr. S. Araki T. Honma S. Yanagihara K. Ushio 《International archives of occupational and environmental health》1980,46(2):151-157
Summary Maximum motor nerve conduction velocities in the median nerve (MCV) and blood lead (PbB) were repeatedly measured in 14 lead exposed workers with an initial PbB from 0.7 to 4.0 mol/kg (median 2.3 mol/kg) for a period from 3 months to 7 years: A certain dose of Calcium Disodium Ethylenediaminetetraacetic Acid (CaEDTA) was injected intravenously into most of the subjects during the period.In seven subjects, MCV improved by more than 4 m/s during the observation period which involved the first two successive measurements of MCV and PbB, but the remaining seven subjects showed the minimal alteration (within ± 4.0 m/s). The initial value of MCV was significantly slower (P < 0.01) and the decrease in PbB was significantly greater (P < 0.05) in the group of subjects having shown the improvement of MCV by more than 4 m/s.The initial value of MCV was significant in determining the alteration in MCV in multiple regression analysis and, together with the change in PbB, explained 31% of the alteration in MCV between the first two successive measurements. The initial level of PbB, dose of CaEDTA, time interval between the measurements and age played no essential part in the alteration in MCV.The alteration in MCV throughout the whole observation period in each subject significantly correlated with the concurrent change in PbB (r=–0.573, P < 0.001). 相似文献
143.
Summary Adrenomyeloneuropathy (AMN) is reported in two kindreds. In the first family, four male patients were affected: two adults with the full clinical picture but with a different chronology of the main symptoms, a third adult with central nervous system involvement and a child who died early with adrenal insufficiency. The second family included two male patients with AMN, one adult with raised ACTH levels and his nephew with normal adrenal function. Two other young males died with adrenoleukodystrophy (ALD), one being subjected to a postmortem study.Clinical, endocrinological, neurophysiological and pathological studies were performed.The following conclusions can be made: (1) AMN and ALD are closely related entities; (2) there exists a considerable intrafamilial variability of the clinical picture; (3) AMN is to be included in the differential diagnosis of myelopathies and, conversely, signs of central nervous system damage must be sought in male patients with adrenal insufficiency; (4) electron microscopy of nerve twigs brings supportive diagnostic evidence pending the more widespread determination of the C26/C22 fatty acids ratios in cultured fibroblasts or plasma.This paper has been financially supported by the Fonds voor Geneeskundig Wetenschappelijk Onderzoek (grant no. 3.0004.81) and by the Baron Charles Bracht Foundation 相似文献
144.
R. O. Murray M.D. F.R.C.P.Ed. F.R.C.R. Janet McCredie M.D. F.R.C.R. F.R.A.C.R. 《Skeletal radiology》1979,4(2):57-71
Melorheostosis is characterised radiologically by hyperostotic linear densities in bone. These densities have a peculiarly segmental distribution which does not correspond with the anatomical course of blood vessels or mixed nerve roots of the limbs. So far this distribution has lacked any valid explanation, although it has been suggested to be a developmental error as a result of an embryonic metameric disturbance. Inman and Saunders in 1944 described a sensory nerve supply to skeletal structures with sclerotomes representing the zones of the skeleton supplied by individual spinal sensory nerves. Radiographs of 30 cases from the Radiological Museum of the Institute of Orthopaedics, London, have been reviewed and an attempt has been made to correlate the sclerosing lesions with the sclerotomes. The investigation was handicapped by paucity of films and clinical information, but in 19 cases the skeletal abnormalities were considered to correspond with a single sclerotome or part thereof. These studies were convincing when films of an affected hand or foot were available. In the remaining 11 cases multiple sclerotomes appeared to be involved and the clinical manifestations were correspondingly more severe. It is proposed that melorheostosis may be the late result of a segmental sensory nerve lesion, to account for its sclerodermal distribution. The association with linear scleroderma is discussed, since it has been suggested that these cutaneous lesions are related to the same nerve segment. Eight cases showed para-articular ossification of soft tissues which may be related to involvement of a corresponding myotome. 相似文献
145.
P. -E. Paulev C. Gry M. Døssing 《International archives of occupational and environmental health》1979,43(1):37-43
Summary No difference was found between the nerve conduction velocities of the ulnar nerve of 32 lead exposed workers in the mill of a lead-zinc mine, compared to that of a control group of 14 persons. The lead exposure period was 2–37 months (mean: 12.9 months).The blood lead of the exposed group was as an average (± SD): 53 ± 16 g per 100 ml compared to 11 ± 4 g per 100 ml for the control group.Further studies are needed to establish a possible dose-time-response relationship for the possible, subclinical neuropathy found by some investigators. 相似文献
146.
R. Papeschi 《Psychopharmacology》1977,55(1):1-7
Behavioral data are reviewed that give evidence for an indiscriminate involvement of brain catecholamines (CA), especially dopamine (DA), in nervefunction, regardless of the time elapsed from their synthesis. Critical analysis of biochemical and pharmacological studies shows that a clear-cut distribution of brain catecholamines in two compartments [newly synthesized (NS) and main storage] is not at all established, and moreover that there is no adequate proof that the difference in turnover rates attributed to these two supposed pools is due to a preferential extraneuronal release of NS-CA during nerve function rather than to a preferential (nonfunctional) intraneuronal deamination of NS-CA, or at least of NS-DA. 相似文献
147.
Summary Serial nerve biopsies were performed at an early, and at an advanced stage of the disease in 2 patients with progressive neural muscular atrophy. The early biopsy showed a complete loss of the large diameter and thickly myelinated fibres, as well as an expansion of the endoneurial interstitium in both cases. Myelinated and unmyelinated fibres exhibited axonal degeneration in all biopsies occasionally. Onion bulb formation, a typical feature of peripheral neuropathy in neural muscular atrophy, was found to be prominent only in the latter biopsies. As regards the formal pathogenesis of hypertrophic neuropathy in neural muscular atrophy, axonal dystrophy and interstitial changes of the endoneurium were regarded as primary phenomena, demyelination and onion bulb formation as secondary. A possible causal relation between axonal dystrophy and interstitial changes, observed in these cases, is discussed in the light of the present literature.
Zusammenfassung Bei 2 Patienten mit progressiver neuraler Muskelatrophie wurden Nervenbiopsien jeweils in einem frühen und in einem fortgeschrittenerem Stadium der Erkrankung entnommen und verglichen. In beiden Fällen zeigten bereits die frühen Biopsien ein völliges Fehlen der großkalibrigen, dickbemarkten Axone. Ebenfalls als frühe Veränderung wurde eine Erweiterung des endoneuralen Interstitiums festgestellt. Eine geringe Anzahl der vorhandenen bemarkten und unbemarkten Axone in allen Biopsien wies degenerative Veränderungen auf. Die für die progressive neurale Muskelatrophie typische Zwiebelschalenbildung der Schwannschen Zellen — möglicherweise eine Reaktion auf wiederholte De-und Remyelinisierungsvorgänge um dystrophische Axone — trat erst in den späteren Biopsien deutlicher hervor. Hinsichtlich der formalen Genese der hypertrophischen Neuropathie bei neuraler Muskelatrophie sind nach diesen Beobachtungen axonale Dystrophie und interstitielle Veränderungen des Endoneuriums als primäre Entmarkung und Zwiebelschalenbildung als sekundäre Phänomene zu betrachten. Die Möglichkeit einer kausalen Beziehung zwischen axonaler Dystrophie und interstitiellen Veränderungen wird an Hand der vorliegenden Befunde und Literatur diskutiert.相似文献
148.
MRI of the intraorbital optic nerve in patients with autosomal dominant optic atrophy 总被引:3,自引:0,他引:3
Votruba M Leary S Losseff N Bhattacharya SS Moore AT Miller DH Moseley IF 《Neuroradiology》2000,42(3):180-183
Measurements of the intraorbital optic nerve were made using high-resolution coronal MRI in 10 adults with autosomal dominant
optic atrophy. Comparisons were made with previous studies of 10 normal adult subjects. The cross-sectional diameters of the
optic nerve and the perineural subarachnoid space were measured and a ratio of there diameters at anterior, mid and posterior
positions along the optic nerve was determined. We found a statistically significant difference in the mean optic nerve: sheath
ratio between the control group and patients with autosomal dominant optic atrophy. At anterior, mid and posterior locations
along the optic nerve it is significantly smaller in patients with optic atrophy. We have demonstrated that the loss of ganglion
cells, previously documented in dominant optic atrophy, is associated with a significant loss of optic nerve tissue and thinning
of the nerve along its length.
Received: 6 July 1999/Accepted: 22 July 1999 相似文献
149.
150.
经皮电刺激与电针治疗纤维肌痛综合征疗效对比 总被引:9,自引:1,他引:9
目的 :对比经皮电刺激与电针治疗纤维肌痛综合征 (FS)的疗效差异。方法 :将 66例患者随机分为经皮电刺激治疗组 (A组 )、电针治疗组 (B组 )、药物对照组 (C组 )进行临床疗效的对比研究。其中A组和B组均采用以FS常见的 1 8个压痛点邻近穴位为刺激点 ,C组采用口服阿米替林为主的西药。结果 :A组及B组的有效率及痊愈显效者 6个月、1 2个月及 2 4个月随访结果同C组比较 ,其差异具有非常显著性意义 (P <0 0 1 ) ,但A组同B组比较 ,差异无显著性意义 (P >0 0 5)。结论 :经皮电刺激或电针刺激穴位治疗纤维肌痛综合征的疗效优于药物组 ,而经皮电刺激是一种无创痛且被患者乐于接受的方法 相似文献