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71.
Lehmann O Jeltsch H Lehnardt O Pain L Lazarus C Cassel JC 《The European journal of neuroscience》2000,12(1):67-79
This study assessed behavioural and neurochemical effects of i.c.v. injections of both the cholinergic toxin 192 IgG-saporin (2 microgram) and the serotonergic toxin 5,7-dihydroxytryptamine (5,7-DHT; 150 microgram) in Long-Evans female rats. Dependent behavioural variables were locomotor activity, forced T-maze alternation, beam walking, Morris water-maze (working and reference memory) and radial-maze performances. After killing by microwave irradiation, the concentrations of acetylcholine, monoamines and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the hippocampus, frontoparietal cortex and striatum. 192 IgG-saporin reduced the concentration of acetylcholine by approximately 40% in the frontoparietal cortex and hippocampus, but had no effect in the striatum. 5,7-DHT lesions reduced the concentration of serotonin by 60% in the frontoparietal cortex and 80% in the hippocampus and striatum. Noradrenaline was unchanged in all structures except the ventral hippocampus where it was slightly increased in rats given 192 IgG-saporin. Cholinergic lesions induced severe motor deficits but had no other effect. Serotonergic lesions produced diurnal and nocturnal hyperactivity but had no other effect. Rats with combined lesions were more active than those with only serotonergic lesions, showed motor dysfunctions similar to those found in rats with cholinergic lesions alone, and exhibited impaired performances in the T-maze alternation test, the water-maze working memory test and the radial-maze. Taken together and although cholinergic lesions were not maximal, these data show that 192 IgG-saporin and 5,7-DHT lesions can be combined to selectively damage cholinergic and serotonergic neurons, and confirm that cholinergic-serotonergic interactions play an important role in some aspects of memory, particularly in spatial working memory. 相似文献
72.
基底节钙化与急性偏瘫综合征的关系 总被引:5,自引:1,他引:5
目的 探讨基底节钙化(BGC)与小儿急性偏瘫综合征(AHS)发病的关系。方法 对34例AHS病例有关,临床资料进行回顾性分析、总结。结果 39.4%AHS患儿有BGC,其中79.8%发病前10d内有明确轻微头部外伤史。临床表现为不同程度的一侧急性偏瘫,部分有惊厥发作,但无意识障碍,颅内压增高不明显。CT扫描显示在一侧或双侧基底节区点或片状钙化,其附近存在类圆形点或片状低密度灶。结论 BGC与外伤后AHS的发生有一定关系,故对年龄小于3岁、外伤后近期有偏瘫或惊厥发作患儿,应注意有BGC的可能。 相似文献
73.
Sperm number and condition affect the number of basal cells and their expression of macrophage antigen in the murine epididymis 总被引:1,自引:0,他引:1
Unilateral ligation of the mid-corpus epididymis, the proximal vas deferens and imposition of an abdominal temperature for 6 days as well as bilateral castration for 3, 6 or 14 days, resulted in a change in epithelial composition of the adult murine epididymis with regard to the number and antigen expression of basal cells. There were fewer basal cells per tubule cross-section with fewer expressing F4/80 antigen when spermatozoa were absent from the proximal lumen following short-term castration. Conversely, more basal cells with more of them demonstrating macrophage antigen expression were evident when more or damaged spermatozoa were in the proximal lumen after corpus ligation and exposure to abdominal temperature or in the cauda after long-term withdrawal of androgen support. By contrast, ligation of the vas deferens did not lead to tubule distension, and hence sperm accumulation, and did not alter the basal cell population in the cauda epididymis. The data suggest that epididymal basal cells respond in number and macrophage antigen expression to the presence of sperm autoantigens in the lumen with little dependence on circulating androgens. These changes may represent responses to minimise the interaction of sperm autoantigens with the immune system and the risk of immunological infertility. 相似文献
74.
Gorlin's syndrome (also known as basal cell nevus syndrome, Gorlin?Goltz syndrome, and nevoid basal cell carcinoma syndrome) is a rare, inherited disorder characterized by multiple basal‐cell epitheliomas, intracranial calcification, keratocysts of the mandible, and unusual and striking skeletal abnormalities. We present the interesting case of a 45‐year‐old woman who was informed that she had fibrous dysplasia of the extremity at another institution before extensive radiological work‐up showed a diffuse skeletal process. The skeletal abnormalities, in conjunction with the patient's history of multiple basal cell carcinomas, is consistent with the diagnosis of Gorlin's syndrome. We describe this unusual case of striking radiological and scintigraphic findings in a patient with Gorlin's syndrome. 相似文献
75.
Patients with xeroderma pigmentosum (XP) are highly sensitive to ultraviolet radiation and prone to develop multiple skin
malignancies. We report two children under 6 years of age with XP who each developed two histologically different types of
malignancies simultaneously. We conclude that it is of importance to be aware of the possibility of multiple malignancies
of different types, even in young children.
Accepted: 16 December 1996 相似文献
76.
Nerve growth factor (NGF) plays a crucial role in synaptic plasticity during brain development and adulthood by activating a dual receptor system composed of TrkA and p75 (p75NTR) receptors. Exogenous NGF modulates the expression of both receptors. Little is known about the ability of endogenous NGF to regulate the expression of these receptors in basal forebrain cholinergic terminals. The ability of glucocorticoids to increase NGF expression in the hippocampus prompted us to investigate whether the synthetic glucocorticoid dexamethasone (DEX) increases TrkA and p75NTR expression in NGF-target cholinergic neurons in developing rats. We first examined the effect of DEX on NGF mRNA by in situ hybridization. DEX given systemically (0.5 mg/kg, sc) for 1 week to 7-day-old rats elicited an increase in NGF mRNA levels in the dentate gyrus of the hippocampus and superficial layers II and III of the cerebral cortex. Immunohistochemical analysis of p75NTR and TrkA levels revealed a dramatic increase in p75NTR immunoreactivity (IR) in both basal forebrain and hippocampus and TrkA IR in the hippocampus. Interestingly, in DEX-treated rats more axonal terminals were immunopositive for p75NTR in the hippocampus and cortex, suggesting an increase in p75NTR IR in cell bodies as well as in terminals. Our data indicate that the endogenously produced NGF elicits biological changes similar to those of the exogenously delivered NGF. We suggest that glucocorticoids might regulate and coordinate cholinergic neuronal maturation by increasing the biosynthesis of NGF. 相似文献
77.
目的 探讨年龄、基础卵泡刺激素(FSH)值对控制性促超排卵(COH)结局的预测价值。方法 对2003年1月至2004年11月在同济医院生殖中心行体外受精(IVF)/单个精子卵母细胞内注射(ICSI)与胚胎移植(ET)助孕术的1252个周期结局进行回顾性分析。结果 随年龄、基础FSH值的上升,获卵数和可移植胚胎数逐渐减少,周期取消率逐渐升高。但在基础FSH值≤18mU/ml时,只有年龄与临床妊娠显著相关,而基础FSH值与临床妊娠无显著相关性。结论 年龄、基础FSH值的上升与COH结果负性相关,而年龄则是妊娠的独立预测因子。 相似文献
78.
“劳倦过度,房室不节”肾阳虚模型小鼠舌象研究 总被引:5,自引:0,他引:5
目的:观察“劳倦过度,房室不节”诱发的肾阳虚模型小鼠舌象变化。方法:选健康雄性昆明种小白鼠45只,随机分为对照组、模型组和治疗组3组,各15只。用强迫小鼠游泳法造成劳倦过度;以Colldege效应诱导雄性小鼠房室不节,建立肾阳虚小鼠模型。用金匮肾气丸作为治疗药物,6周时,观察各组小鼠舌象,做石蜡切片,HE染色,显微镜观察拍片。结果:模型组呈淡白舌,齿痕明显;治疗组基本为淡白舌,齿痕不明显。模型组舌乳头密度、舌分裂相频数较对照组明显下降(P<0.01),上皮层厚度、角质层厚度较对照组显著增加(P<0.05);治疗组较模型组乳头密度显著增加,上皮层厚度显著减小(P<0.05),舌分裂相频数增加,角质层厚度下降,但无统计学意义。结论:肾阳虚模型小鼠舌黏膜病理改变以上皮增殖减慢、代谢降低、萎缩和退变为主要特征。 相似文献
79.
An olfactory span task that required rats to discriminate an olfactory stimulus added to an increasing list of such stimuli (nonmatching-to-sample; NMTS) was employed to assess the role of the basal forebrain cholinergic system in the animals' olfactory working memory capacity. A separate group of animals was trained in a matching-to-sample (MTS) version of this task that did not tax span performance. NMTS animals required significantly more sessions to reach an olfactory span of 18 stimuli than MTS rats. Infusions of the cholino-immunotoxin 192 IgG-saporin into the basal forebrain resulted in decreases of cortical acetylcholinesterase (AChE)-positive fibre density ranging from 80% in frontodorsal and frontoparietal regions to 35% in the pyriform cortex and 24% in the olfactory bulb. Postsurgery span performance was significantly reduced in lesioned NMTS but not MTS animals. Span performance in lesioned NMTS animals recovered following 4 weeks of postoperative training; however, these animals' span remained vulnerable to the effects of increased intertrial intervals. The distribution of errors in lesioned animals indicated a recency effect. In NMTS animals, olfactory span performance during the initial two postoperative weeks correlated significantly with AChE-positive fibre density in neocortical but not olfactory areas. The privileged, automatic processing of olfactory stimuli in rats may have contributed to the transience of the lesion effect. The results support the crucial role of cortical cholinergic input in the mediation of aspects of processing capacity. 相似文献
80.
针当前对药学领域计算机技术应用的特点,对药学类专业计算机基础课程的教学目标作了详细的分析和论述。结合药学类专业的教学的实际情况,对该类专业的计算机基础教学的课程设置提出可行方案,就教学改革中几个值得注意的问题作了分析。 相似文献