The Specific Role of cGMP in Hippocampal LTP

Previous results have suggested that cGMP is involved in hippocampal long-term potentiation (LTP), perhaps as the presynaptic effector of a retrograde messenger. However, other studies have failed to replicate some of those results, making the role of cGMP uncertain. We therefore reexamined this question and identified several variables that can affect the contribution of cGMP. First, brief perfusion with 8-Br–cGMP before weak tetanic stimulation produced long-lasting potentiation in the CA1 region of hippocampal slices, but more prolonged perfusion with 8-Br–cGMP before the tetanus did not produce long-lasting potentiation. Second, the activity-dependent long-lasting potentiation by cGMP analogs was reduced when NMDA receptors were completely blocked, indicating that NMDA receptor activation contributes to, but is not required for, the potentiation. The amount of reduction of the potentiation differed with different protocols, and in some cases could be complete. Third, LTP produced by strong tetanic stimulation in the stratum radiatum of CA1 (which expresses eNOS) was blocked by inhibitors of soluble guanylyl cyclase or cGMP-dependent protein kinase, but LTP in the stratum oriens (which does not express eNOS) was not. The results of these experiments should help to explain some of the discrepant findings from previous studies, and, in addition, may provide insights into the mechanisms and functional role of the cGMP-dependent component of LTP.     

Selective Abolition of the NMDA Component of Long-Term Potentiation in Mice Lacking mGluR5

The mechanisms underlying the differential expression of long-term potentiation (LTP) by AMPA and NMDA receptors, are unknown, but could involve G-protein-linked metabotropic glutamate receptors. To investigate this hypothesis we created mutant mice that expressed no metabotropic glutamate receptor 5 (mGluR5), but showed normal development. In an earlier study of these mice we analyzed field-excitatory postsynaptic potential (fEPSPs) in CA1 region of the hippocampus and found a small decrease; possibly arising from changes in the NMDAR-mediated component of synaptic transmission. In the present study we used whole-cell patch clamp recordings of evoked excitatory postsynaptic currents (EPSCs) in CA1 pyramidal neurons to identify the AMPAR- and NMDAR-mediated components of LTP. Recordings from control mice following tetanus, or agonist application (IS, 3R-1-amino-cyclopentane 1,3-dicarboxylic acid) (ACPD), revealed equal enhancement of the AMPA and NMDA receptor-mediated components. In contrast, CA1 neurons from mGluR5-deficient mice showed a complete loss of the NMDA-receptor-mediated component of LTP (LTP_NMDA), but normal LTP of the AMPA-receptor-mediated component (LTP_AMPA). This selective loss of LTP_NMDA was seen in three different genotypic backgrounds and was apparent at all holding potentials (−70 mV to +20 mV). Furthermore, the LTP_NMDA deficit in mGluR5 mutant mice could be rescued by stimulating protein kinase C (PKC) with 4β-phorbol-12,13-dibutyrate (PDBu). These results suggest that PKC may couple the postsynaptic mGluR5 to the NMDA-receptor potentiation during LTP, and that this signaling mechanism is distinct from LTP_AMPA. Differential enhancement of AMPAR and NMDA receptors by mGluR5 also supports a postsynaptic locus for LTP.     

对分心物特性抑制中位置因素的排除

本研究以汉语单字词为材料,使用反应时技术,考察在归类住条中分心物的位置因素是否也与分心物特性因素一样,影响被试对探测显示中目标的反应时间（RTDT）。结果表明,RTDT不随分心物位置数目变化而变化,只随着分心物特性数目变化而变化．由此得出,象归类这种属于语义表征的、与位置无关的任务中被试并不抑制分心物出现的位置,并可进一步推论,分心物抑制可能是一种灵活机制。     

4—9岁儿童逻辑推理能力的研究——对J.Piaget某些实验的验证

本文是对皮亚杰“物体守恒”实验的验证。从而探讨了4—9岁儿童在形成守恒概念中的逻辑思惟发展过程,为编制智力测验量表提供了有关参考数据。     

从产业经济发展的角度考证我国古代职业教育的发源

职业技术教育是随产业的产生而产生、随产业的发展而发展的,这是职业技术教育产生与发展的原始动因和持续动力,也是我们考证职业教育何时形成的重要判断依据。在我国奴隶社会之前,社会经济文化的发展还没有导致社会经济产业化的形成,人们之间的社会分工还没有达到专门的职业化。那时,技术技能的学习与传授是在日常生活和日常劳动中实现的,是偶然的、分散的、带有一定随机性的,没有专门的教育场所和教育人员。夏商周三代,少数脑力劳动者成为专门掌管文化及农业、手工业、商业等行业的官吏,实行“子习父学”的职官教育,奴隶和平民没有接受专业技术教育的权利。春秋桓、管时期,社会生产力进一步发展,产业分工越来越细致化、专职化,产业经济的发展要求具备相应的职业教育;齐桓公为称霸诸侯任用管仲为相,推行“四民分业定居制度,从而最早产生了我国历史上真正意义的职业教育。     

从“孔子学院”看汉语和中国教育的国际化认同

教育无国界是有识之士的共识,也是不可逆转的潮流。中国采取在世界各地建立孔子学院的形式加大吐人对汉语和中国的教育的认识,文章从孔子学院在世界各地的运作形式,阐述了孔子学院发展近四年多来对世界的影响和世界对汉语和中国教育的国际化认同以及对有关的问题进行了反思。     

Soccer player's and closed-skill athletes' execution of a complex motor skill

The main purpose of this study was to investigate possible differences in speed and accuracy of motor execution among female soccer players in an Expert Soccer group, a Novice Soccer group, and a Closed-skill Athlete group. There were two main findings. Firstly, both soccer groups performed better than the Closed-skill Athletes on speed and accuracy of motor execution. Secondly, there were no significant differences between Expert and Novice soccer players in the speed and accuracy of motor execution.     

发掘情感策略的实验研究

将对内含隐性情感因素的教材内容实施情感性处理的一种策略——发掘情感策略运用于语文教学,进行现场的教学实验研究。研究结果表明：在内含隐性情感因素的文科教材内容中,可以运用发掘情感策略来对其进行情感性处理;这对促进学生的认知学习和情感发展、提高课堂教学质量是有效的。     

Neural substrates of word generation during stroke recovery: the influence of cortical hypoperfusion

Several studies have demonstrated reorganization of cognitive and motor function caused by stroke. This study examined the influence of hypoperfused brain regions, in addition to the area of the infarct itself, on reorganization of the cognitive processes underlying word generation in stroke patients. In addition, we also sought to determine the influence of hypoperfusion on the blood oxygen level dependent/(BOLD) effect. Subjects with left and right subacute or chronic subcortical strokes, along with normal controls, were imaged while performing a verbal fluency task (word generation). The study population included six normal subject and six stroke patients with subcortical infarcts and cortical hypoperfusion in the middle cerebral artery territory who had recovered or improved markedly in word fluency. While normal subjects displayed a left-lateralized fronto-temporo-parietal and bilateral cingulo-striatal-thalamic-cerebellar network, the activation pattern of stroke patients was determined both by the hypoperfused regions and infarcted areas of the brain. Specifically, patients showed diminished BOLD effect in the cortical regions that were hypoperfused, even though their infarcts were subcortical, and showed increased BOLD effect in the homologous regions of the normal hemisphere. This finding raises the possibility that cortical hypoperfusion in the absence of infarct can cause shift of language functions to the opposite, intact hemisphere. However, reduced BOLD effect in the task relative to rest was found in hypoperfused regions in two patients, raising the possibility that regional function persisted, even though vascular reactivity was impaired. Results illustrate the complexities of functional imaging studies of recovery in patients with vascular lesions.     

论唯识学的第八识及其种子

本文着重讨论了佛家唯识学是如何通过建立第八识及其种子学说,以解决众生的生死轮回与觉悟解脱等等问题。