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91.
G. Finali M. Piccirilli C. Oliani G. L. Piccinin 《The Italian Journal of Neurological Sciences》1992,13(2):141-148
In a double blind randomized crossover trial lasting 6 months selegiline, a selective MAO-B inhibitor, was tested against placebo for activity on verbal memory performances in Alzheimer-type dementia (DAT). Verbal memory was assessed with the Rey-Auditory-Verbal Learning Test at the start of treatment, at the time scheduled for crossover (90 days) and at the end of the trial (180 days). The results suggest that selegiline possesses significant activity on some memory parameters, which seems to depend on an improvement both in information processing abilities and in learning strategies at the moment of acquisition
Sommario In uno studio doppio cieco cross-over, randomizzato verso placebo della durata di sei mesi, è stata analizzata l'influenza della selegilina, inibitore selettivo delle MAO-B, sulle prestazioni di memoria verbale di 22 pazienti con diagnosi clinica di demenza tipo Alzheimer (DAT). L'esame della memoria verbale è stato effettuato con il Rey-Auditory Verbal Learning test all'inizio del trattamento, dopo 90 giorni, momento previsto per il cross-over, e dopo 180 giorni, al termine della sperimentazione. I risultati suggeriscono una significativa efficacia della selegilina su alcuni parametri di memoria, che sembrano riconducibili ad un miglioramento sia delle capacità di elaborazione delle informazioni, sia delle strategie di apprendimento al momento dell'acquisizione.相似文献
92.
目的观察奥明格健脑口服液对改善小鼠记忆作用的影响。方法断乳小鼠,体重12~14g,每组14~16只。把实验动物随机分为正常对照组、高剂量组、中剂量组和低剂量组,连续给样30d,进行跳台和水迷宫试验,以上试验按同样方法重复一次。结果两次小鼠实验表明,灌胃奥明格健脑口服液1mo后,跳台试验中受电击动物数和错误总数,各试验组均低于对照组,其中高剂量试验组显著低于对照组,而且潜伏期显著延长。水迷宫试验中,动物到达终点所需时间和错误总数,高中剂量组试验组均显著低于对照组。结论奥明格健脑口服液具有改善动物记忆的作用。 相似文献
93.
Primary objective: This study seeks to extend previous findings by documenting memory performance in a sample of 70 children at 5 years post-injury. It was anticipated that increasing injury severity would be associated with decreased performance on working and complex memory tasks. It was also expected that injury severity would significantly predict memory, but that the time from insult to subsequent testing would be associated with an increased relationship to non-injury factors.
Research design: Participants were assessed at 5 years post-injury, aged between 6-14 years, using measures of immediate, working and complex memory.
Methods and procedures: The sample comprised 18 children who had sustained a severe TBI, 24 with a moderate TBI, 11 with a mild TBI and 17 healthy controls, matched for age, gender and socio-economic-status.
Results: Results indicated that severe TBI was associated with decreased complex auditory-verbal memory performance, although children with TBI did not display impairment on immediate, working or complex visual-spatial memory. While injury severity significantly predicted complex memory outcome, non-injury factors failed to significantly predict either working or complex memory performance.
Conclusions: Future research should be engineered towards further clarifying what influences recovery from childhood TBI in the elongated post-injury period. 相似文献
Research design: Participants were assessed at 5 years post-injury, aged between 6-14 years, using measures of immediate, working and complex memory.
Methods and procedures: The sample comprised 18 children who had sustained a severe TBI, 24 with a moderate TBI, 11 with a mild TBI and 17 healthy controls, matched for age, gender and socio-economic-status.
Results: Results indicated that severe TBI was associated with decreased complex auditory-verbal memory performance, although children with TBI did not display impairment on immediate, working or complex visual-spatial memory. While injury severity significantly predicted complex memory outcome, non-injury factors failed to significantly predict either working or complex memory performance.
Conclusions: Future research should be engineered towards further clarifying what influences recovery from childhood TBI in the elongated post-injury period. 相似文献
94.
Illana Gozes John Glowa Douglas E. Brenneman Susan K. McCune Eric Lee Heiner Westphal 《Journal of molecular neuroscience : MN》1993,4(3):185-193
The molecular mechanisms responsible for behavior are largely unknown. A state of the art model, paving the path from genes
to behavior, is offered by transgenic animals. Candidate molecules are classic neuropeptides, such as vasoactive intestinal
peptide (VIP). Transgenic mice harboring a chimeric VIP gene driven by the polyoma promoter were produced. Behavioral studies
revealed learning impairment and prolonged retardation in memory acquisition in the genetically altered animals. Furthermore,
reduced performance was observed when the male transgenic mice were tested for sexual activity in the presence of receptive
females. Surprisingly, radioimmunoassays showed an approx 20% decrease in the VIP content of the transgenic mice brains. To
directly assess genetically reduced VIP content as a cause for learning impairment, transgenic mice carrying diphtheria toxia-encoding
sequences driven by the rat VIP promoter were created. These animals had reduced brain VIP and exhibited deficiencies in learning
abilities, strongly supporting an important neurobiological function for VIP in vivo. 相似文献
95.
Demetrius Moskophidis Elisabeth Laine Rolf M. Zinkernagel 《European journal of immunology》1993,23(12):3306-3311
Antiviral cytotoxic memory CD8+ T cells adoptively transferred to mice which are persistently infected with lymphocytic choriomeningitis virus WE or DOCILE initially proliferated extensively; they either caused the death of the recipient or, alternatively, disappeared within a few days. Apparently, the complete and coordinated induction and stimulation by widely distributed viral antigen caused these memory T cells to die before virus had been eliminated from the host. Thus memory T cells are as susceptible to peripheral exhaustion/deletion as unprimed T cells. These results indicate possible limitations of exclusively CD8+ T cell-mediated adoptive immunotherapy against viral infections or tumors. 相似文献
96.
97.
A. Perio J. P. Terranova P. Worms R. M. Bluthe R. Dantzer K. Biziere 《Psychopharmacology》1989,97(2):262-268
The recognition of an unfamiliar juvenile rat by an adult rat has been shown to imply short-term memory processes. In this study the effect of various psychotropic drugs on this investigatory behaviour was examined. The procedure was as follows: an unfamiliar juvenile rat was placed in the home cage of an adult rat for 5 min. The time spent by the adult rat in investigating the juvenile was recorded. The adult rat was then immediately treated with vehicle or test compounds, and was again exposed for 5 min to the same juvenile 2 h later. At this time point vehicle-treated rats no longer recognized the juvenile rat, i.e. the time of investigation was similar to that observed during the first presentation. Arecoline (1 and 3 mg/kg IP), physostigmine (0.05 and 0.1 mg/kg SC), RS86 (0.5 mg/IP) and nicotine (0.125 and 0.5 mg/kg IP) reduced in a dose-dependent fashion the time spent in investigating the juvenile during the second exposure. This result cannot be attributed to nonspecific effects, since it was not observed when a different juvenile was used for the second exposure. The effect of arecoline was reversed by scopolamine, but not by methylscopolamine. Aniracetam reduced investigatory behaviour at the dose of 50 mg/kg IP. FG 7142 (5 mg/kg IP) and -CCM (0.4 mg/kg IP) were also active and their effect was reversed by Ro 15-1788. dl-Amphetamine (0.5 and 1 mg/kg IP), nomifensine (1.25–10 mg/kg IP) and strychnine (0.25 and 0.5 mg/kg IP) were ineffective or reduced this behaviour unspecifically. Social recognition may therefore represent a useful and simple test to detect compounds which enhance short-term, olfactory, memory and to assess in the same animals the specificity of this activity. 相似文献
98.
Bartholdy C Stryhn A Hansen NJ Buus S Thomsen AR 《European journal of immunology》2003,33(7):1941-1948
DNA vaccination is an efficient way to induce CD8+ T cell memory, but it is still unclear to what extent such memory responses afford protection in vivo. To study this, we induced CD8+ memory responses directed towards defined viral epitopes, using DNA vaccines encoding immunodominant MHC class I-restricted epitopes of lymphocytic choriomeningitis virus covalently linked to beta2-microglobulin. This vaccine construct primed for a stronger recall response than did a more conventional minigene construct. Despite this, vaccinated mice were only protected against systemic infection whereas protection against the consequences of peripheral challenge was limited. Phenotypic analysis revealed that DNA vaccine-primed CD8+ T cells in uninfected mice differed from virus-primed CD8+ T cells particularly regarding expression of very-late antigen (VLA)-4, an adhesion molecule important for targeting T cells to inflammatory sites. Thus, our DNA vaccine induces a long-lived memory CD8+ T cell population that provides efficient protection against high-dose systemic infection. However, viral replication in solid non-lymphoid organs is not curtailed sufficiently fast to prevent significant virus-induced inflammation. Our results suggest that this is due to qualitative limitations of the primed CD8+ T cells. 相似文献
99.
妊娠中晚期暴露于可卡因对子代海马发育的影响 总被引:1,自引:0,他引:1
目的 建立妊娠中晚期暴露于可卡因的小鼠动物模型 ,研究可卡因对子代海马的发育是否具有影响以及这种影响在可卡因诱发的神经行为异常发病机理中可能所起的作用。方法 运用水迷宫方法观察可卡因对子鼠青春期空间辨别能力的影响 ,分别采用甲苯胺蓝染色技术和免疫组织化学结合图象分析技术观察海马中锥体细胞和神经胶质细胞的发育情况。结果 妊娠中晚期暴露于可卡因的小鼠子代在青春期海马锥体细胞极性紊乱 ,发育不良 ,未迁移到正常位置 ;神经胶质细胞数目减少。水迷宫结果显示可卡因可引起子代寻找平台的潜休期延长。结论 妊娠中晚期暴露于可卡因可引起子代青春期海马发育异常 ,这可能在可卡因引起子代空间辨别能力下降的发病机理中起着重要作用。 相似文献
100.
MIA SON JEONG‐OK KONG SANG‐BAEK KOH JAEYOUNG KIM MIKKO HÄRMÄ 《Journal of sleep research》2008,17(4):385-394
We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns. 相似文献