三种常用DIF检测方法的比较研究

本研究在对DIF作出新的更为严格的界定、对三种常用的DIF检澍方法进行详细介绍的基础上．以1999年高考英语试卷75道选择题为研究材料,对三种常用的DIF检测方法进行了实证研究。结果表明：MH方法与SIBTEST方法检测的敏感性较STND方法高;MH方法与SIBTEST方法检出的一致性很高;SIBTEST方法具有较好的性能,在实际应用中可以作为首选的方法;在进行DIF检测时,样本容量在1000左右为宜。     

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.     

Neuropsychological findings of extrapontine myelinolysis without central pontine myelinolysis

Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are well recognized syndromes related to the rapid correction of hyponatremia, which are reported to show brain stem signs and various movement disorders. Cognitive dysfunction and neuropsychological findings, however, have seldom been reported. Cognitive manifestations in osmotic myelinolysis may have been underestimated due to the prominent brain stem symptoms and movement disorders. We report a case of EPM without CPM and describe the neuropsychological findings of EPM. The absence of CPM in this case made it possible to test neuropsychological function in the acute stage. Neuropsychological testing showed severe impairment of attention, verbal and visual memory, visuospatial function, and frontal/executive function. Language and language-related functions were normal except naming.     

结直肠癌诊断模式的若干思考

结直肠癌是常见的消化道恶性肿瘤,然而在临床上得到诊断时大多已经到了中晚期,错过了最佳的治疗时机。近年来,随着基因相关技术及生物信息技术的迅猛发展,结直肠癌诊断方法得到不断改进,但早期诊断仍不尽如人意。因此现有的诊断模式值得我们去深思,从哲学意义上探索更为完善的诊断模式。     

十五年来中国男性择偶标准的变化

对《中国妇女》1985年至2000年15年间每隔5年选择一年,并在每一季度中选择一期杂志,统计男性刊登的征婚启事,总共得到332例。采用统计学方法进行定量研究。发现中国男性在15年间对自身的人品、财产、相貌的重视程度显著增高,对自身的婚史和事业的重视程度明显降低;对女方的持家能力的重视程度显著增高,对女方的健康和工作的重视程度显著降低。当代中国男性的择偶标准随时间的推移有了明显的变化,但仍受到中国传统观念的影响。     

稷下学术精神与当代学术发展

稷下学术精神是我国传统学术文化的宝贵遗产,它蕴涵五个基本元素,即学术与政治的和谐互动、学术批评与学术争鸣、学术开放与学术对话、学术人才与学术自由、学术创新与学术实践.这五个元素在学术发展价值意义上起到的是土壤优质、脊梁挺直、血脉涌动、风貌洒脱、动力强劲的良好作用.我们学术界的一个急不可待的任务,是必须克服目前由于经济大潮给人们带来的浮躁心态和狂妄心理,应该沉静下心思来认真发掘和钻研老祖宗、贤人志士们留下的学术的真精神,扎扎实实地做好学术发展的每一个环节、每一件事情.稷下学术精神对当代中国学术发展的启示和借鉴作用是无论如何也不可忽视的.     

经济法试题DIF的参数法检测研究

该研究基于项目反应理论的Samejima等级反应模型(GRM),在MULTILOG软件支持下,应用参数检测方法,对某年度全国性资格考试的某科目试卷中经济法部分的21个项目做了DIF检测分析。结果如下:存在性别DIF的项目一个,存在民族DIF的项目四个,存在工作性质DIF的项目一个。其中项目68在民族层面上表现为一致性DIF,项目64既存在民族DIF又存在工作性质DIF。通过对项目统计量、反应曲线的分析和专家的讨论,文章最后还分析了产生这些DIF的几个可能的原因。     

在国际道德经论坛闭幕式上的致辞

女士们,先生们: 今天,我有幸参加国际道德经论坛闭幕典礼这样一个盛事,感到非常高兴.我对论坛的圆满成功表示热烈祝贺! 崇尚和谐、爱好和平,是中华民族高尚的精神品格.在春秋战国时期,中华民族的先哲们就确立起"和为贵"、"和而不同"、"重生贵和"的价值理念.     

构建社会主义和谐社会中的道德建设新指向

构建社会主义和谐社会的命题,要求实现道德建设"由圣入凡"的转变.这种转变的新指向是:以日常生活批判实现从传统道德向现代道德的转化,把以人为本与现代性"平民化人格"联系起来,以生态和谐观念寻求公德与私德的统一.     

The Role of Leadership and Trust in Creating Structural Patterns of Team Procedural Justice: A Social Network Investigation

We adopt a social network perspective to investigate the distinct structural patterns (i.e., centralization and density) of procedural justice (PJ) in teams and the antecedent factors that create them. Across 2 longitudinal field studies in which we gathered social network data from 1,008 workers on 138 teams (Study 1) in China and 672 workers on 125 teams (Study 2) in the United States, we found that differentiation in leader–member exchange relationships significantly influenced the centralization and density of PJ within a team by affecting the level of intrateam trust. Specifically, the more differentiated leader treatment team members received, the lower the level of trust within a team, which resulted in more concentrated (high centralization) and fewer (low density) social interactions among members regarding team PJ. Furthermore, differentiated leader treatment of team members was especially damaging to intrateam trust and, in turn, the structural patterns of team PJ when team members were in close proximity and highly sensitive to equity issues.