治疗血浓度下抗癫(癎)药对未成熟脑发育影响的实验研究

目的 探讨抗癫(癎)药物(AEDs)在治疗血浓度下对未成熟脑发育的影响.方法 以AEDs血浓度达到临床治疗稳态血浓度为实验剂量,设立健康幼鼠及成年SD大鼠氯硝西泮(CNP)、苯巴比妥(PB)、丙戊酸(VPA)、托吡酯(TPM)实验组及正常对照组(各18只).AEDs灌胃5周,于停药后次日、2周及1个月末,行Morris水迷宫及穿梭箱测试.停药当天记录体重、脑重,海马及额叶组织行苏木素-伊红(HE)、尼氏染色及电镜观察.结果 (1)停药后次日及2周的穿梭箱实验,幼鼠CNP和PB组逃避潜伏期明显长于对照组.即使停药后1个月,幼鼠CNP[(6.05±2.04)s]及PB组[(5.81±1.75)s]与对照组的差异仍有统计学意义[(4.75±2.43)s,P＜0.01].而停药后2周,成年鼠各AEDs组与对照组已无差异;(2)Morris水迷宫实验,分别于停药后次日、2周及1个月,幼鼠CNP和PB组登平台潜伏期均长于对照组.而成年鼠各组登平台潜伏期于停药后2周已无差异;(3)幼鼠CNP组脑重(1.67±0.04)g,PB组脑重(1.66±0.04)g,较对照[(1.75±0.06)g]轻;(4)神经元广泛变性坏死,神经细胞数[CNP组为(76.87±18.60)个/200倍视野,PB组(72.60±17.26)个/200倍视野]较对照少[(109.13±33.73)个/200倍视野,P＜0.01];(5)停药1个月后,PB组幼鼠神经元超微结构仍异常.结论 长期服用PB、CNP可引起未成熟脑学习记忆功能及脑组织病理学持续异常,PB对未成熟脑的损伤存在可能是不易恢复的.     

多巴胺受体的结构和功能

多巴胺是大脑中含量最丰富的儿茶酚胺类神经递质。多巴胺作为神经递质调控中枢神经系统的多种生理功能。多巴胺系统调节障碍涉及帕金森病，精神分裂症，Tourette综合征，注意力缺陷多动综合征和垂体肿瘤的发生等。本文综述了多巴胺受体的共同特征和各个受体的独特特征，以及它们在中枢神经系统的分布和功能，重点强调了多巴胺受体与学习记忆的关系。     

妊娠压力对大鼠子代早期空间学习记忆能力的影响

【目的】探索妊娠期精神压力对大鼠子代早期空间学习、记忆能力的影响。【方法】实验采取产前束缚压力,建立妊娠期大鼠精神压力暴露模型。然后对子代进行Morris水迷宫测试,分析妊娠期压力对子代早期学习和记忆的影响及性别间的差异,同时检测实验前、后子鼠的血清肾上腺酮的变化。【结果】①在隐蔽平台试验中,对照组的平均潜伏期较实验组短,但差异无显著性(F=0.599,P>0.05)。②在保持力试验中,对照组在原平台所在象限逗留的时间大于实验组,差异有显著性(F=4.588,P<0.05)。③子代血清肾上腺酮的测定结果表明:水迷宫测试前,实验组和对照组相比,差异无显著性(F=0.169,P>0.05);实验后,实验组血清肾上腺酮比对照组高,差异具有显著性(F=6.098,P<0.05)。【结论】①妊娠压力可导致子代学习,记忆能力的改变;②妊娠压力造成子代在应激情况下血清肾上腺酮的过度分泌。③妊娠压力对子代的影响没有明显性别差异。     

Effects of haloperidol on the multitrial partial reinforcement extinction effect (PREE): evidence for neuroleptic drug action on nonreinforcement but not on reinforcement

Two experiments investigated the effects of haloperidol (0.1 mg/kg) on the partial reinforcement extinction effect (PREE). In experiment 1 two groups of rats were trained to run in a straight alley using six trials/day with an intertrial interval (ITI) of 5–8 min. The continuously reinforced (CRF) group received food reward on every trial. The partially reinforced (PRF) group was rewarded on a quasi-random 50% schedule. All animals were then tested in extinction. Haloperidol was administered in a 2 × 2 design, i.e., drug-no drug in acquisition and drug-no drug in extinction. In experiment 2 two groups of rats were trained to press a lever in an operant chamber using a discrete trial procedure of ten trials/day with an ITI of 60 s. The CRF group was rewarded on each trial and the PRF group was rewarded on a quasi-random 50% schedule. Haloperidol was administered for 22 days prior to the start of the PREE procedure as well as throughout acquisition and extinction. The PREE, i.e., increased resistance to extinction of PRF as compared to CRF animals, was obtained in both experiments in all drug conditions. In both experiments haloperidol increased the rate of extinction. Experiment 1 revealed that this effect was entirely dur to the administration of the drug in extinction, independently of the drug condition in acquisition. In contrast to previous results in a one trial/day procedure, the administration of haloperidol to CRF animals did not increase resistance to extinction, failing to support the notion that neuroleptics attenuate the rewarding properties of reinforcement.     

Organization and physiology of thesubstantia nigra

Summary A comprehensive review of the literature on the anatomy, electrophysiology and pharmacology of thesubstantia nigra is presented. A diagram is developed taking into account the interneuronal interactions of neurotransmitters and receptors that control firing rates and neurotransmitter releases. The central features of the diagram are a positive dopaminergic feedforward process and a positive feedback mechanism mediated by extrasynaptic substance P diffusing from striatal terminals to dopaminergic dendrites of thezona compacta neurons. This loop can enhance the transmission of information from thestriatum through thepars reticulata output neurons. The loop is controlled at the level of zona compacta neurons by a negative feedback supported by the dendritic release of dopamine and boosted by pedunculopontine activation mediated by muscarinic receptors. The output of the loop is controlled by two negative feedforward processes, both involving GABAergic striatonigral afferents. Application of the model to pharmacological studies of diverse behaviors including seizures, turning, and conditioned behaviors reveals unforseen relationships and may offer insights into, and directions for, further analysis of the mechanisms and functions involved.     

Experiences and perceived roles of occupational therapists working with children with special learning needs during transition to school: A pilot study

Occupational therapists provide support to children with special learning needs and their families during the child's transition from early childhood to mainstream school. Little has been documented regarding the role and experiences of occupational therapists working with children, families and teachers during transition in an Australian context. Six paediatric occupational therapists from one geographical area in New South Wales were interviewed and asked to relay their role and experiences when providing a service to children with special learning needs during their transition to school. Participants described their role to include: preparing the child for school; working with school personnel; and providing parental support. Although participants described both positive and negative experiences, among the negative experiences were: limited time to provide a service; recommendations to school personnel not being followed; school personnel not being supportive; feeling uncomfortable in the classroom; and limited involvement in planning. Participants described a role which is consistent with current school-based occupational therapy practice; however, in the participants' experience, there was a gap between the ideal service and what participants were able to provide. This included limited collaboration with teachers.     

对构建特色医院文化的思考

21世纪的医院是文化的医院,21世纪医院的竞争是文化的竞争,谁能构建出具有特色的医院文化,谁就能赢得竞争主动权。构建特色医院文化,核心是形成共同的理想和精神支柱;关键是打造“学习型”医院组织;根本是树立以人为本、诚信求实的服务理念;目标是树立良好的医院形象;基础是加快医院信息化建设。     

Effectiveness of an intensive stress intervention workshop for senior managers

This study investigates the efficacy of an intensive, integrated approach to stress reduction and coping enhancement directed towards an educated, upper level management population. Ninety‐five US governmental senior managers participated in a 35‐h stress management retreat held over a 3.5‐day period. The retreat combined didactic and experiential activities that were designed to increase participants' knowledge of stress liabilities and coping skills. Participants were encouraged to make positive lifestyle changes and to create specific action plans for the year following the workshop. Evaluations of participant satisfaction were completed at the close of the workshop. Eighty‐three participants completed baseline and follow‐up Stress and Coping Inventory (SCI) assessments in order to identify durable changes in these measures. Across 10 months, participants showed significant improvements in their overall Global Balance scores, psychological symptoms, depression symptoms, and all major coping scales, including Health Habits, Social Support, Responses to Stress and Life Satisfactions. Therefore, an intensive, multifaceted approach to stress intervention is a viable option for encouraging sustained behavioural change. Copyright © 2003 John Wiley & Sons, Ltd.     

Learning and retention of movement sequences in Parkinson's disease.

The purpose of this study was to examine motor learning and retention given extensive practice in two fundamentally different movement sequences. One sequence was a memory-driven task (performing a series of whole body positions from memory) and the other a context-driven task (buttoning). Practice took place over 3 weeks, with performance measured weekly; retention was measured weekly for 3 weeks after practice. There were 7 people with Parkinson's disease (PD) and 7 age-matched neurologically healthy people who participated in this study. Both groups improved performance on both tasks with practice, with the majority of the change for the PD group occurring between 1 and 2 weeks of practice. Although those with PD did not necessarily perform as well as age-matched controls, they learned both sequences in a manner similar to age-matched controls, and exhibited retention across the 3-week retention interval. If people with PD are given sufficient practice they can learn and retain both memory-based and context-driven movement sequences as well as age-matched controls. The results provide support for maintaining physical activity and for intervention through movement therapy.     

Undergraduate and postgraduate dental students''reflection on learning'': a qualitative study

The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described.