20世纪全球卫生发展的回顾与展望

20世纪人类的健康状况发生了革命性的转变,同时也面临着前所未有的挑战。疾病谱的改变及人口寿命的延长以及医疗费用的上涨仍然是困扰各国决策者的难题,卫生发展与改革任重道远。完善健康保障体系最理想的选择方案是政府为居民“购买”基本卫生服务,由国家财政和居民共同承担保险基金,普及初级卫生保健,鼓励多种形式办医,WHO确定的卫生工作目标是各成员国卫生系统改革与发展的指导方针。     

比喻性成语对文章段落回忆的影响

本研究采用随意学习的实验范式,探讨了结句中是否包含比喻性成语以及被试的工作记忆容量大小对文章段落回忆成绩的影响.实验中所有被试被要求阅读6个说明体的文章段落,然后接受一个有提示的回忆测验.研究发现(1)所有被试对结句中包含比喻性成语的段落回忆成绩比结句中没有比喻性成语的段落好.(2)结句中是否包含比喻性成语和被试工作记忆容量之间存在着交互作用.若结句中包含比喻性成语,段落的回忆成绩不受被试工作记忆容量的制约,反之则会.这些结果可能表明,比喻性成语的某些特点,如形象性或易记性,作为一种辅助手段促进了被试对文章内容的记忆、保持和回忆.     

普通话韵律词重音知觉

实验一研究了韵律词重音的多个声学相关物,及其对韵律词重音知觉贡献的大小,结果表明,按照贡献大小的次序,影响普通话韵律词重音感知的声学参数是：时长、音高、频谱倾斜和平均能量。实验二研究非声学参数因素对普通话韵律词重音知觉的影响,实验结果表明,听者关于普通话韵律词重音方面的语言学知识对韵律词重音的知觉有显著影响。     

对学生学习成绩与社会行为的交叉滞后分析

采用二元交叉滞后回归分析法考察小学四、五年级学生和初中一、二年级学生在21个月中的学校适应与学习成绩之间的关系。结果发现,在同时性测量中,由教师评价获得的中小学生的社交领导能力、定向耐挫能力、果敢性社交技能得分和同伴积极提名分数与他们的学习成绩之间均存在正相关关系,而他们的攻击破坏得分、学习适应不良得分以及小学生的同伴消极提名分均与他们的学习成绩有显著的负相关关系。二元交叉滞后回归分析结果表明,小学生在前测中的社交领导能力得分、攻击破坏得分、定向耐挫得分、学习适应不良得分、果敢性社交技能得分同伴积极和消极提名得分均可以预测21个月后的学习成绩。对中学生来说,这种预测关系只在攻击破坏行为、定向耐挫行为中存在。中小学生的害羞抑制得分和焦虑抑郁得分与他们的学习成绩之间既没有同时性的相关关系,也没有滞后性的预测关系。     

Dichotic Perception of Mandarin Tones by Chinese and American Listeners

The dichotic perception of Mandarin tones by native and nonnative listeners was examined in order to investigate the lateralization of lexical tone. Twenty American listeners with no tone language background and 20 Chinese listeners were asked to identify dichotically presented tone pairs by identifying which tone they heard in each ear. For the Chinese listeners, 57% of the total errors occurred via the left ear, indicating a significant right ear advantage. However, the American listeners revealed no significant ear preference, with 48% of the errors attributable to the left ear. These results indicated that Mandarin tones are predominantly processed in the left hemisphere by native Mandarin speakers, whereas they are bilaterally processed by American English speakers with no prior tone experience. The results also suggest that the left hemisphere superiority for native Mandarin tone processing is similar to native processing of other tone languages.     

连续和同时线索化条件下的返回抑制容量

利用线索-靶子模式进行了返回抑制容量的两个实验。实验一对外周数个位置连续线索化,实验二对外周数个位置同时线索化。结果表明：(1)在连续线索化条件下,当线索化位置是相邻时,返回抑制容量可以达到4个,当线索化位置是间隔时,返回抑制容量只有1个。(2)在同时线索化条件下．当线索化位置是相邻时,返回抑制容量可以达到3个,当线索化位置是间隔时．返回抑制容量只有1个。结果支持认为存在着两种不同的返回抑制的观点,即一种是弥散性的,其容量较大;另一种是集中性的,其容量只有一个。     

儿童角色认同对记叙文记忆与理解影响的研究

通过考查儿童对不同类型记叙文的记忆与理解的情况,探讨儿童角色认同对记叙文理解与记忆的影响。结果表明。角色认同有助于儿童对记叙文的记忆与理解。而且,这种角色认同是已具备基本书面语言能力的儿童在阅读中自然而然地发生的,提示对认同没有重要的影响。     

Differential effect of TEA on long-term synaptic modification in hippocampal CA1 and dentate gyrus in vitro.

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.     

Differential Effect of TEA on Long-Term Synaptic Modification in Hippocampal CA1 and Dentate Gyrus in vitro

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.     

刻板印象的内隐效应与内一外群体效应的实验研究

采用间接测量方法分别探讨刻板印象的内隐效应与内一外群体效应。实验结果表明 :( 1)内隐刻板印象是存在的 ,并且在很大程度上是一种无意识内隐影响的表现 ;( 2 )刻板印象是一个自动化的过程 ;( 3)刻板印象表现出强烈的“内一外群体效应”