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11.
The neurotoxic actions of kainate were examined in incubated slices of adult and immature rat cerebellum using light- and electron-microscopy. In the adult, Purkinje cells and inhibitory interneurones became selectively necrotic at concentrations between 5 micro M and 20 micro M. At 30 micro M, granule cells also became affected. In the immature cerebellum, at an age (8 days after birth) when the parallel fibres (thought to use glutamate as transmitter) are largely yet to be developed, selective toxicity was still evident but Purkinje cells and inhibitory interneurones were about 10-fold, and granule cells about 30-fold, less sensitive to kainate than in the adult. Kainate and other excitotoxins also increased cyclic GMP levels in cerebellar slices, apparently through the activation of excitatory amino acid receptors. In the adult tissue, the dose-cyclic GMP response curve to kainate was biphasic suggesting the presence of two components. The lower concentrations of kainate eliciting the first component mirrored those inducing selective necrosis of Purkinje cells and inhibitory interneurones while the second component correlated with necrosis of granule cells. Similar correlations applied to the immature cerebellum, but here kainate neurotoxicity appeared to be associated with the activation of receptor types different from those evident in the adult. It is suggested that kainate receptors, whose activation is associated with both neurotoxic damage and elevation of cyclic GMP levels, are located on all cell types in the adult cerebellum, with Purkinje cells and inhibitory interneurones displaying a higher sensitivity to kainate than granule cells. The lower sensitivity of immature cerebellum to the neurotoxic effect of kainate is probably due to lower levels of kainate receptors. 相似文献
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蒙药毛勒日—达布斯—4汤中微量元素及氨基酸含量的测定 总被引:1,自引:0,他引:1
目的:测定蒙药毛勒日-达布斯-4汤中微量元素和氨基酸的含量。方法:用原子吸收分光光度计,测定蒙药毛勒日-达布斯-4汤中几种重要的微量元素含量;用氨基酸自动分析仪测定氨基酸的含量。结果与结论:蒙药毛勒日-达布斯-4汤中含有较高的Mn、Fe、Zn和Mg;含有17种氨基酸,包括7种人体必需氨基酸,氨基酸总量为4.615%(mg/g)。 相似文献
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目的:介绍新的更有效的内痔注射方式。方法:用多普勒血流仪引导注射治疗内痔出血与脱出,与单纯注射治疗对照观察。结果:一年后出血复发率治疗组为10%,对照组为119.17%(P〈0.05);内痔脱出复发率治疗组为18.25%,对照组为25%。结论:用多普勒血流仪引导注射治疗内痔能更有效的闭塞痔动脉。 相似文献
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慢性光化性皮炎的病因诊断及治疗 总被引:1,自引:1,他引:0
目的;探讨慢性光化性皮炎(CAD)的病因,诊断及治疗,方法:查阅文献,对引起CAD的光敏物、发病机理及治疗进行分析,结果:约11%的CAD患者有光敏物接触史;62%光敏性隐匿;27%有慢性皮炎病史;结论:CAD发病与光变态反应有关,避光治疗有效。 相似文献
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Informed consent, parental awareness, and reasons for participating in a randomised controlled study
M van Stuijvenberg MH Suur S de Vos GC Tjiang EW Steyerberg G Derksen-Lubsen HA Moll 《Archives of disease in childhood》1998,79(2):120-125
BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent. 相似文献
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植入前诊断是产前诊断非常早的一种方法,目的是放弃携带严重遗传病的胚胎,将健康胚胎植入母体。两种主要的方法是聚合酶链反应(PCR)和荧光原位杂交(FISH)。PCR用于单基因病诊断,FISH用于染色体异常诊断。临床主要应用于存在遗传风险的患者如携带单基因病和染色体易位的患者。随着分子生物学技术的飞速发展,如比较基因组(CGH),全基因组扩增技术(WGA),引物延伸预扩增(PEP),间期核转换技术及DNA芯片技术(DNAchip)等PGD先进检测手段的应用,单细胞用于诊断单基因或多基因突变及染色体疾病,为期不远。 相似文献