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151.
Niijima H Nagao M Nakajima M Takatori T Iwasa M Maeno Y Koyama H Isobe I 《Forensic science international》2000,112(2-3):171-178
One sarin-like and one soman-like organophosphorus agent [bis(isopropyl methyl)phosphonate, BIMP and bis(pinacolyl methyl)phosphonate, BPMP] were injected intravenously (iv) in rats. An increase in the tyrosine phosphorylation of several proteins in the cytosol fraction of the brain was observed. Activation of c-Jun N-terminal kinase (JNK) and slight activation of mitogen-activated protein kinase (MAPK) in the cytosol were also observed. The activation of these enzymes may be related to the high toxicity of these nerve agents. 相似文献
152.
Gotohda T Tokunaga I Kubo S Morita K Kitamura O Eguchi A 《Forensic science international》2000,113(1-3):233-238
Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure. 相似文献
153.
Nishimura A Sawada S Ushiyama I Yamamoto Y Nakagawa T Tanegashima A Nishi K 《Forensic science international》2000,113(1-3):265-269
Several lectins were used to study the localization of glycoconjugates in brain of elderly people and patients with Alzheimer type dementia (ATD) and Down's syndrome (DS). Five kinds of degenerated or deposited materials stained clearly by lectins specific to GalNAC, Gal, Fuc, and/or Man were recognized much in ATD and DS, less in elderly peoples, in addition to the binding of the lectins to neurons. (i) Round shape deposits called corpora amylacea (CA) which consisted of various sizes of round material, existed mainly on the surface of cerebral cortex and some in white matter of the brain. They were colored by Alcian blue (AB), Aldehyde fucsin (AF) and periodic acid shiff (PAS) and weakly by Hematoxylin (H), but not by Eosin (B). They showed clear reactivity with lectins specific to GalNAC, Gal, Fuc and Gal-GalNAC. (ii) Amorphous and variform amyloid deposits existed around blood vessels in the white matter were stained by thioflavin and lectins specific to GalNAC, Gal and Fuc, but not with Man specific lectins and PAS, AB, AF and HE. (iii) Another kind of amyloid deposits which showed a similar characteristic to the previous one and were recognized mainly in white matter and independent blood vessels. These deposits were stained by thioflavin but not by PAS, AB, AF and HE and showed good reactivity with lectins specific to GalNAC, Gal, Fuc, Gal-GalNAC, Gal-GIcNAc and Man. The reactivity with lectins specific to Gal, Fuc, and Man was seen in senile plaques (iv) and neurofibrillary tangles (v). Although at present we are unable to explain the origin of these deposits, it is clear from this study that the glycoconjugates form an integral part of the degeneration in the brain. The lectin staining with GS-I is useful in the forensic pathology to diagnose brain disorders at postmortem examination, since these lectin were able to detect five types of degeneration changes and/or deposits. 相似文献
154.
近几年来美国把对泰国援助中一部分“贈欵”改为貸欵,泰报认为是援助減少了。作者认为貸欵也是援助,但可能使泰国经济发展計划降低要求或中止,言外之音是希望增加“贈欵”。 相似文献
155.
156.
自从1954年7月日内瓦协定订立之后,南越吴庭艶政府把土地改革存在关键性的问题,下了绝大的决心,付诸实施,特别是在土地转移和定居这两个方面。在实施土改计划上,美国的经济和技术援助起了重要的作用。土改计划的初步阶段,现在将近完成,減租和稳定佃期的计划,现在正在继续施行,并普及到全国佃农的3/4,而土地转移计划预 相似文献
157.
158.
柬埔寨迄今发现的最早的高棉碑铭刻于公元611年,最早的梵文碑铭比它晚刻两年。从公元七世纪起,出现一些用两种文字刻成的可确定其年代的碑铭,给我们展示了柬埔寨社会构成的画面。这种画面与我们从中国资料看到的不同,因为这些碑铭表现的是宗教内容而不是世俗生活。根据碑铭,柬埔寨社会至少非正式地被划分为懂得梵文和仅仅懂得高棉语的两部分人。在好几百年的时间里,梵人被用于直接对神谈话的碑铭中,而高棉语则是柬埔寨 相似文献
159.
这篇文章总结了从1921年到1981年苏联青年研究的成就,引用了六十年中出版的近40部著作和调查材料。在总结和回顾苏联青年研究历史经验的基础上,作者主要分析了七十年代以来苏联青年的兴趣、爱好、需求和政治、职业趋向的发展变化,提出了急待研究和解决的问题。此外,作者还兼论了青年研究中的一些基本概念。所有这些对我国当前的青年研究和青年工作科学化都有一定的参考价值。 相似文献
160.
俄罗斯具有丰富的自然资源和工艺潜力。为了民族的经济福利,需要保护资源,开发其潜力,谨慎地利用自然,人文和智能财富以及合理的经营开发制度。为此国际交换及外国投资问题就成为关键课题之一。 若不深入持久地参与国际劳动分工,不与商品、服务、资金、劳动力及科技信息等的国际动态紧密相联,没有一个国家能在现代世界上立足。为了适应采掘工业的投资服务需求,吸引外国资金已成为全世界的实践活动。现阶段在外国投资者或国际项目范围中,销售科技研究成果已成为常事。在现代化标准基础上要发展民族经济,如没有智能、劳动力的国际交换,不吸引外资,同时出口本国资金及工艺是行不通的,这是在全球范围内都适用的道理。 相似文献