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141.
由于受到千百年来传统家庭观念及患者认知能力的影响,同时,由于辅助生殖技术(ART)的专业性、复杂性,ART技术应用的局限性、结果的不确定性以及诊治周期长、费用高等因素的存在,ART知情同意过程面临着困境.ART伦理管理落实真实知情同意的体现在对患者进行充分、全面、如实的信息告知,取得其配偶的同意和支持,完善的、个案化的文书签定,是ART伦理管理落实真实知情同意的体现.  相似文献   
142.
墨西哥近年的医疗卫生改革取得了巨大的成就.通过简要地描述墨西哥人群健康状况、医疗卫生资源现状、卫生系统绩效以及与中国的比较,分析了墨西哥三轮卫生改革的特点、存在的问题以及面临的挑战,旨在提出墨西哥卫生系统与医疗保障体系改革对我国医疗卫生改革的启示和借鉴.  相似文献   
143.
考察解题反思对数学学业优生和差生解题结果及所用策略的不同影响。选取初一至初三年级的数学学业优生和差生为被试,以一套连加数问题为实验材料,进行一对一的测试,前后进行两次测试。对反思组优差生(优生12人,差生10人)和无反思组优差生(优生14人,差生14人)解题过程的比较,发现:1)解题后立即进行反思能够提高差生的解题正确率,但是延长解题时间;2)先前的解题反思对优生和差生后续解题时的正确率和解题时间均不产生明显影响;3)解题后立即进行反思能够促进优生和差生使用高效策略,放弃低效策略;4)先前的解题反思在后续解题中仍然促进学生使用高效策略,对优生的促进作用比对差生更明显。  相似文献   
144.
Since the brain neurotransmitter changes characterising panic disorder remain uncertain, we quantified brain noradrenaline and serotonin turnover in patients with panic disorder, in the absence of a panic attack. Thirty-four untreated patients with panic disorder and 24 matched healthy volunteers were studied. A novel method utilising internal jugular venous sampling, with thermodilution measurement of jugular blood flow, was used to directly quantify brain monoamine turnover, by measuring the overflow of noradrenaline and serotonin metabolites from the brain. Radiographic depiction of brain venous sinuses allowed differential venous sampling from cortical and subcortical regions. The relation of brain serotonin turnover to serotonin transporter genotype and panic disorder severity were evaluated, and the influence of an SSRI drug, citalopram, on serotonin turnover investigated. Brain noradrenaline turnover in panic disorder patients was similar to that in healthy subjects. In contrast, brain serotonin turnover, estimated from jugular venous overflow of the metabolite, 5-hydroxyindole acetic acid, was increased approximately 4-fold in subcortical brain regions and in the cerebral cortex (P < 0.01). Serotonin turnover was highest in patients with the most severe disease, was unrelated to serotonin transporter genotype, and was reduced by citalopram (P < 0.01). Normal brain noradrenaline turnover in panic disorder patients argues against primary importance of the locus coeruleus in this condition. The marked increase in serotonin turnover, in the absence of a panic attack, possibly represents an important underlying neurotransmitter substrate for the disorder, although this point remains uncertain. Support for this interpretation comes from the direct relationship which existed between serotonin turnover and illness severity, and the finding that SSRI administration reduced serotonin turnover. Serotonin transporter genotyping suggested that increased whole brain serotonin turnover most likely derived not from impaired serotonin reuptake, but from increased firing in serotonergic midbrain raphe neurons projecting to both subcortical brain regions and the cerebral cortex.  相似文献   
145.
The hippocampal theta rhythm is a prominent oscillation in the field potential observed throughout the hippocampus as a rat investigates stimuli in the environment. A recent computational model [Hasselmo, M. E., Bodelon, C., & Wyble, B. P. (2002a). A proposed function for hippocampal theta rhythm: separate phases of encoding and retrieval enhance reversal of prior learning. Neural Computation, 14, 793-817. Neuromodulation, theta rhythm and rat spatial navigation. Neural Networks, 15, 689-707] suggested that the theta rhythm allows the hippocampal formation to alternate rapidly between conditions that promote memory encoding (strong synaptic input from entorhinal cortex to areas CA3 and CA1) and conditions that promote memory retrieval (strong synaptic input from CA3 to CA1). That model predicted that the preferred theta phase of CA1 spiking should differ for information being encoded versus information being retrieved. In the present study, the spiking activity of CA1 pyramidal cells was recorded while rats performed either an odor-cued delayed nonmatch-to-sample recognition memory test or an object recognition memory task based on the animal's spontaneous preference for novelty. In the test period of both tasks, the preferred theta phase exhibited by CA1 pyramidal cells differed between moments when the rat inspected repeated (match) and non-repeated (nonmatch) items. Also in the present study, additional modeling work extended the previous model to address the mean phase of CA1 spiking associated with stimuli inducing varying levels of retrieval relative to encoding, ranging from novel nonmatch stimuli with no retrieval to highly familiar repeated stimuli with extensive retrieval. The modeling results obtained here demonstrated that the experimentally observed phase differences are consistent with different levels of CA3 synaptic input to CA1 during recognition of repeated items.  相似文献   
146.
人与非人动物嵌合体的研究,作为人类提高自身健康素质的技术工具,以科学技术的形式改变着人们的生活方式和思维方式,寻找遗传性或者难治性疾病的致病基因和治疗新途径,追求个人和社会整体的良好生存状态,有着巨大的医疗价值,符合"行善"的伦理原则,应该允许限制性的开展.考虑到可能引发的伦理和高技术风险,履行审慎的准入制度.进行规范的伦理管理和严格的法规、行政管理是非常必要的.  相似文献   
147.
该研究力图探讨教养及气质因素与失败恐惧的关系,以及失败恐惧对学业成绩的影响及其机制。对427名高一学生施测失败表现评估量表、父母教养方式评价量表、行为抑制/行为激活量表、防御性期望和反思量表、自我阻碍量表,并收集被试期末考试成绩。相关分析、回归分析、路径分析等表明,失败恐惧与教养、气质因素均有密切关系;其对学业成绩具有间接的消极影响。  相似文献   
148.
Weber & Hsee (1998) proposed the “cushion effect” as an explanation of the higher risk taking observed in some East Asian samples, relative to Western samples. Yates, Lee, & Shinotsuka (1992 ) proposed that the overconfidence observed in most Asian countries, relative to Western countries, reflects differences in the number of arguments typically recruited in those countries. This study examined the 2 seemingly separated domains of research: risk taking and overconfidence. It compared individual and collective (both family and group) decisions among Chinese in Singapore. This permitted tests of both the cushion and the argument recruitment hypotheses. The overall results obtained no support for the cushion effect and partial support for the argument recruitment hypotheses.  相似文献   
149.
人工语法范式下内隐学习的脑机制及其教育启示   总被引:1,自引:0,他引:1  
人工语法范式是研究内隐学习实验的重要范式。利用脑成像技术的研究发现:人工语法范式下内隐学习发生时,额叶、枕叶、顶叶以及基底神经节与内隐学习有密切关系。该结果对当前教育教学产生一定启示,即教师要多给学生创造知识迁移的机会;培养学生的动手实践活动;重视学习过程中内隐学习与外显学习的先后顺序和有序结合。  相似文献   
150.
失败恐惧研究述评   总被引:1,自引:0,他引:1  
失败恐惧(Fear of Failure,简写为FF)作为一种消极的情绪体验,近年来越来越多地受到研究者的关注。文章主要介绍了失败恐惧概念结构的演变、测量工具由单维到多维的发展过程、失败恐惧特质形成和预防的心理动力学探讨以及多维测量工具在失败恐惧干预方法中的作用。在此基础上,文章对未来研究进行了展望,比如失败恐惧是否存在跨文化、跨领域的差异,我国经济转型时期失败恐惧研究具有怎样的现实意义等  相似文献   
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