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61.
Yang H  Jin G  Ren D  Luo S  Zhou T 《Brain and cognition》2011,76(1):206-210
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.  相似文献   
62.
为探讨挫折情境下自我肯定对执行功能的影响,创设挫折和非挫折情境,采用价值观自我肯定干预,通过Stroop范式和2-back范式分别测量抑制控制和工作记忆的刷新能力。结果发现,挫折情境下的Stroop任务和2-back任务反应时均高于非挫折情境;挫折情境下自我肯定组在Stroop任务和2-back任务上的反应时均显著低于非自我肯定组,而非挫折情境下两组的反应时没有显著性差异;Stroop效应量在情境与肯定条件上的交互作用不显著。结果表明挫折降低了执行功能的任务表现,自我肯定干预能够改善挫折情境下执行功能相关的任务成绩,促进了个体对工作记忆任务的刷新能力和Stroop任务的认知表现,但对抑制控制能力的改善没有明显作用。  相似文献   
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研究胰岛素样生长因子结合蛋白2(IGFBP-2)及胰岛素样生长因子结合蛋白6(IGFBP-6)在结直肠癌中的表达及临床意义。采用免疫组织化学法及RT-PCR方法检测结直肠癌、结直肠腺瘤及癌旁正常黏膜组织中IGFBP-2及IGFBP-6的蛋白及mRNA的表达情况,结合临床病理资料进行统计学分析。IGFBP-2及IGFBP-6蛋白的阳性表达及mRNA的表达量在三组组织中均存在异常表达情况,且差异有明显的统计学意义(P〈0.05),在结直肠癌组IGFBP-2、IGFBP-6的阳性表达在肿瘤浸润深度、有无淋巴结转移及Duke's分期存在差异,有明显的统计学差异(P〈0.05)。临床可以把二者作为结直肠癌诊断及预后的早期预测指标。  相似文献   
65.
急性应激会增强个体对威胁刺激的注意偏向,但急性应激是增强了对威胁刺激的注意定向还是损害了对威胁刺激的注意解除还不清楚。本研究采用社会评估冷压任务和点探测任务,结合事件相关电位技术,考察急性应激对威胁刺激注意偏向影响的认知机制。在进行社会评估冷压任务后,应激组个体的状态焦虑和皮质醇浓度显著升高。在注意偏向中,应激组对威胁刺激的注意解除比控制组更慢,应激组和控制组在对威胁刺激的注意定向上无显著差异。ERP结果上,威胁刺激诱发应激组比控制组产生了更负的SPCN,在N2pc上没有显著差异。应激组和控制组皮质醇增量的差异和N2pc、SPCN的组间差异均有显著正相关。这些结果说明,急性应激增强对威胁刺激的注意偏向是因为其损害个体对威胁刺激的注意解除,这可能是因为急性应激损害了与注意解除相关的额-顶网络的功能所致。  相似文献   
66.
Depression and anxiety are hightly prevalent among patients with Type 2 Diabetes (T2D), however not commonly related to outcomes, treatment and comorbidities. Eating behaviors could also have an implication. To evaluate the relation between mood and eating behaviors with demographic, physical, treatment, biochemical profiles and chronic comorbidities in T2D we conducted this exploratory cross sectional study in a population from Mexico. Hospital Anxiety and Depression Scale and the Three Factor Eating Questionnaire Revised 21 (TFEQ-R21) were correlated with age, gender, blood pressure, treatment and comorbidities (nephropathy, neuropathy, retinopathy and cardiopathy). Multi-linear regression models and 2k factorial analyses were conducted. Sixty-one patients (31 male) 55 years old (SD 13) with at least 5 years of T2D were included. Anxiety correlated with depression (r = 0.25, p < 0.05). Gender (women) (std B 0.026, p < 0.001), insulin therapy (std B 0.3, p = 0.11), systolic blood pressure (std B 0.263, p = 0.02) and cardiovascular disease (std B 0.232, p = 0.035) predicted depression. Insulin therapy had a positive effect in cognitive restraint. (std B 0.32, p = 0.001). Age (std B 0.37, p = 0.003) and systolic blood pressure (std B 0.237, p = 0.048) predicted positively emotional eating (not previously published). 2k factorial analyses proved additive interaction between complications and insulin therapy with depression. This study supports the relation between mood disorders and eating behaviors with demographic, physical, treatment, biochemical profiles and chronic comorbidities in T2D and the additive interaction between factors and mood disorders.  相似文献   
67.
采用事件相关电位技术,考察内隐多效性选择及其神经机制。被试的任务是认真观看配对的纯色图片刺激,并进行分类按键反应。实验结果发现,在P2上,积极启动刺激比对照刺激激发了更大的P2波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更大的P2波幅,其中右脑的效应最大。在N2上,积极启动刺激比对照刺激激发了更小的N2波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更小的N2波幅,其中右脑的效应最大。在P3上,积极启动刺激比对照刺激激发了更大的P3波幅; 对比对照刺激,积极启动刺激在左脑、大脑中部和后脑诱发了更大的P3波幅,其中右脑的效应最大。研究结果表明当外显目标与内隐目标同时被呈现时,被试趋向于做多效性选择,这可能表明无意识信息加工具有相当大的权重。且右后部脑区可能是加工多效性刺激的核心和关键区域,P3成分可能反应了内隐多效性选择的精细加工过程,能够作为内隐多效性选择的有效的ERPs指标。  相似文献   
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69.
This article tested a model of parenting stress as a mediator between maternal depressive symptoms, emotion regulation, and child behavior problems using a sample of homeless, substance‐abusing mothers. Participants were 119 homeless mothers (ages 18–24 years) and their young children (ages 0–6 years). Mothers responded to questions about their depressive symptoms, emotion regulation, parenting stress, and child behavior problems. A path analysis showed that maternal depressive symptoms were positively associated with child behavior problems through increased parenting stress whereas maternal cognitive reappraisal was negatively associated with child behavior problems through decreased parenting stress. Moreover, maternal expressive suppression was negatively related to child externalizing problems. Findings support the parenting stress theory and highlight maternal parenting stress as a mechanism associated with homeless children's mental health risk. This study has significant implications for understanding the parenting processes underlying child's resilience in the context of homelessness and maternal substance use.  相似文献   
70.
This study examined the intergenerational transmission of fathering among young, African American fathers in rural communities. A sample of 132 African American young men living in the rural South reported on the quality of their relationship with their biological and social fathers in the family of origin, their own involvement with their young children, and relational schemas of close, intimate relationships. Results of path analyses supported the hypothesized mediational model, such that a better relationship with one's biological (but not social) father predicted increased father involvement in the next generation, and this association was partially mediated through positive relational schema after controlling for a range of covariates. Tests of moderated mediation indicated that the link between relational schema and father involvement was significantly stronger among fathers of girls than fathers of boys. Findings highlight the unique influence of close, nurturing father–child relationships for downstream father involvement, and the role of relational schemas as a mechanism for intergenerational transmission among young, rural, African American fathers of girls.  相似文献   
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