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151.
长寿不仅取决于良好的生活习惯,还取决于基因的作用。美国波士顿“衰老研究所”的科学家们,最近通过对137组长寿的兄弟姐妹(共300余人,年龄为91~108岁)的脱氧核糖核酸进行详尽比较和分析,发现长寿者身上果然具有与众不同的所谓“长寿基因”,而且还找到了这些“长寿基因”的大概位置。主持此项研究的波尔斯医生指出,百岁老人十分罕见,在人口中仅占万分之一,但当你在一个家族中发现竟有好几个百岁老人时,你就能相信:长寿不仅取决于培养良好的生活习惯,而且更取决于基因的作用。这就是说,“遗传优势”在决定一个人能活得较长时,起的往往是“主… 相似文献
152.
采用班级整群抽样法选取1847名3~6年级小学生(男生987名;平均年龄10.73±1.16岁)及其家长为被试,采用问卷法考察父母心理控制与小学生欺负行为的关系,同时探讨敌意归因和冷酷无情的中介作用。结果发现:(1)父母心理控制显著正向预测小学生的欺负行为;(2)冷酷无情在父母心理控制与小学生欺负行为间的关系中存在中介作用,敌意归因不发挥中介作用;(3)父母心理控制对小学生欺负行为影响的中介机制不存在显著的性别差异和学段差异。本研究结果表明,冷酷无情是父母心理控制影响小学生欺负行为的重要机制,但敌意归因不是。研究者和实践者应注重对欺负者情感加工能力的关注和干预。 相似文献
153.
154.
荀子"化性起伪"."隆礼重法"的政治思想是建立在他的性恶的人性论基石上的。以礼为本、德法并举、德主刑辅、礼义教化与法律强制相辅相成,是他政治思想的核心内容,也是其对儒家德治思想的创新发展。剔除其封建糟粕,它对我们今天建设和谐小康社会仍可提供有益的启示。 相似文献
155.
不同阶层心理健康观念及需求状况的调查研究 总被引:3,自引:0,他引:3
运用开放式和封闭式问卷调查法 ,对不同阶层共 483人的心理健康观念及心理健康需求状况进行了调查研究。结果表明 :( 1 )不同阶层、不同年龄段的人关于心理健康标准的观念具有显著差异。 ( 2 )人们认为 ,心理健康的人应具有的最典型特征是“处世乐观、热情、诚恳”和“心平气和、与世无争、乐于助人”。 ( 3 )心理不健康的人或心理变态的人所表现的最典型特征是“性格孤僻、与人不合群”和“对生活失去信心、悲观”。 ( 4)虽然不少人认为心理健康与咨询工作者当前最急需开展的工作是“宣传心理健康知识、开展心理卫生服务” ,但只有极少的人能够正视自己的心理健康需求 ,提出自己需要心理健康服务或咨询。 相似文献
156.
A widely adopted approach in cognitive psychology research is to analyze changes in the response time to a stimulus onset
in order to infer information about the cognitive functioning of a subject being tested. But current techniques have inherent
variations in the timing between stimulus activation and stimulus display of up to tens of milliseconds, thereby introducing
significant errors when response time or the latency of neural responses is measured. This article presents a novel yet easy-to-implement
solution for improving resolution in the synchronizing of stimulus activation and stimulus display. Unlike traditional methods
in which the stimulus onset is set as the time at which the routine for displaying the stimulus is called, this approach uses
DirectX to monitor the scan line of CRTs and sets the stimulus onset to the time at which the scan line arrives at the position
where the stimulus is to be drawn. This approach removes the uncertainty involved in having a time delay between the activation
of the display routine and the actual time at which the display occurs, improving the accuracy of response time and latency
period measurements to within 200 μsec. With a specially developed driver, this solution can generate a trigger signal synchronized
precisely with the stimulus onset in all popular Windows systems (including Windows 2000/XP). 相似文献
157.
This study examined the interactive effects of job demands, control, and individual characteristics on upper respiratory illnesses and immune function. Having high job control appeared to lessen the linkage between job demands and poor health among individuals with high self-efficacy and those who perceived that they were not often responsible for negative job outcomes. Conversely, having high job control exacerbated the association between job demands and poor health among inefficacious individuals. Implications for promoting more healthful work environments and facilitating employee coping are discussed. 相似文献
158.
The effectiveness of tetraethylammonium (TEA) and high-frequency stimulation (HFS) in inducing long-term synaptic modification is compared in CA1 and dentate gyrus (DG) in vitro. High-frequency stimulation induces long-term potentiation (LTP) at synapses of both perforant path-DG granule cell and Schaffer collateral-CA1 pyramidal cell pathways. By contrast, TEA (25 mM) induces long-term depression in DG while inducing LTP in CA1. The mechanisms underlying the differential effect of TEA in CA1 and DG were investigated. It was observed that T-type voltage-dependent calcium channel (VDCC) blocker, Ni2+ (50 microM), partially blocked TEA-induced LTP in CA1. A complete blockade of the TEA-induced LTP occurred when Ni2+ was applied together with the NMDA receptor antagonist, D-APV. The L-type VDCC blocker, nifidipine (20 microM), had no effect on CA1 TEA-induced LTP. In DG of the same slice, TEA actually induced long-term depression (LTD) instead of LTP, an effect that was blocked by D-APV. Neither T-type nor L-type VDCC blockade could prevent this LTD. When the calcium concentration in the perfusion medium was increased, TEA induced a weak LTP in DG that was blocked by Ni2+. During exposure to TEA, the magnitude of field EPSPs was increased in both CA1 and DG, but the increase was substantially greater in CA1. Tetraethylammonium application also was associated with a large, late EPSP component in CA1 that persisted even after severing the connections between CA3 and CA1. All of the TEA effects in CA1, however, were dramatically reduced by Ni2+. The results of this study indicate that TEA indirectly acts via both T-type VDCCs and NMDA receptors in CA1 and, as a consequence, induces LTP. By contrast, TEA indirectly acts via only NMDA receptors in DG and results in LTD. The results raise the possibility of a major synaptic difference in the density and/or distribution of T-type VDCCs and NMDA receptors in CA1 and DG of the rat hippocampus. 相似文献
159.
Dong Song Xiaping Xie Zhuo Wang Theodore W. Berger 《Neurobiology of learning and memory》2001,76(3):375
The effectiveness of tetraethylammonium (TEA) and high-frequency stimulation (HFS) in inducing long-term synaptic modification is compared in CA1 and dentate gyrus (DG) in vitro. High-frequency stimulation induces long-term potentiation (LTP) at synapses of both perforant path-DG granule cell and Schaffer collateral-CA1 pyramidal cell pathways. By contrast, TEA (25 mM) induces long-term depression in DG while inducing LTP in CA1. The mechanisms underlying the differential effect of TEA in CA1 and DG were investigated. It was observed that T-type voltage-dependent calcium channel (VDCC) blocker, Ni2+ (50 μM), partially blocked TEA-induced LTP in CA1. A complete blockade of the TEA-induced LTP occurred when Ni2+ was applied together with the NMDA receptor antagonist, D-APV. The L-type VDCC blocker, nifidipine (20 μM), had no effect on CA1 TEA-induced LTP. In DG of the same slice, TEA actually induced long-term depression (LTD) instead of LTP, an effect that was blocked by D-APV. Neither T-type nor L-type VDCC blockade could prevent this LTD. When the calcium concentration in the perfusion medium was increased, TEA induced a weak LTP in DG that was blocked by Ni2+. During exposure to TEA, the magnitude of field EPSPs was increased in both CA1 and DG, but the increase was substantially greater in CA1. Tetraethylammonium application also was associated with a large, late EPSP component in CA1 that persisted even after severing the connections between CA3 and CA1. All of the TEA effects in CA1, however, were dramatically reduced by Ni2+. The results of this study indicate that TEA indirectly acts via both T-type VDCCs and NMDA receptors in CA1 and, as a consequence, induces LTP. By contrast, TEA indirectly acts via only NMDA receptors in DG and results in LTD. The results raise the possibility of a major synaptic difference in the density and/or distribution of T-type VDCCs and NMDA receptors in CA1 and DG of the rat hippocampus. 相似文献
160.
对我院2001年~2005年中标的312项科研课题级别与数量,获经费资助情况,中标科研课题的学科(专业)分布,课题负责人的年龄结构进行系统地统计分析,表明我院承担科研课题的能力在逐年提高,取得了很好的科研成绩。中青年科研人员已成为我院科研发展的主力军,促进了学科的发展。 相似文献