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181.
《Journal of Asia》2021,24(3):749-758
Bitter gourd (Momordica charantia L.) has compounds that repel insect pests. Unlike conventional pesticides, these compounds are eco-friendly and beneficial for human health. However the mechanisms by which these compounds repel insects and affect their physiology remains poorly known. Here we used Drosophila melanogaster (Meigen) to address these issues. We tested a wild strain, and a laboratory bred Canton S strain. Bitter gourd extract reduced the viability of developing flies, but did not affect survival in adults. Flies avoided bitter gourd extract in a food choice assay, and consumed a significantly low amount of food mixed with bitter gourd – indicating that it acts as an antifeedant. Transgenic flies with impaired aversive taste sensitive neurons showed a reduced aversion towards bitter gourd extract showing that these compounds act through the bitter sensitive gustatory neurons. Finally, flies also retained the memory of consuming bitter gourd extract for at least 24 hours, suggesting an additional cognitive mechanism for long term aversion. Our study provides the first evidence of bitter gourd compounds acting as antifeedants and also as potent reinforcers of aversive memory in drosophilids. We suggest that flies can be used to understand the physiological and neural mechanisms underlying the mode of action of other such phyto-extracts with the goal of developing potent but less harmful pest control formulations.  相似文献   
182.
Research to understand human responses to wildlife and wildlife issues has predominantly focused on cognitions. Yet, as emotions are basic human responses to wildlife, emotions are important too. Integrating cognition and emotion concepts could foster the overall understanding of human-wildlife relationships. This study tested the relationships between valence (the pleasant-unpleasant dimension of emotion) regarding wildlife and wildlife value orientations (patterns of basic cognitions in the context of wildlife). Also, this study estimated the additional predictive potential of emotion next to cognition for the acceptability of lethal control and support for wildlife conservation. Analyses showed that valence was associated with wildlife value orientations. Valence had additional explanatory value next to cognition for conservation support. Valence, however, did not have additional predictive potential for acceptability of lethal control. Based on these findings, we recommend integrating cognition and emotion measurements in future research to understand human responses to wildlife issues. Also, wildlife managers could take the emotion of stakeholders into account in their communication and decision-making processes.  相似文献   
183.
Growth hormone (GH) replacement therapy with duration of several years is known to be safe and beneficial in GH-deficient adult patients. However, long-term follow-up data on GH substitution, cognition, and well-being are scarce. The purpose of this study was to investigate whether the benefits of GH replacement in psychological functioning found in previous studies lasting up to 2 years are preserved over a 10-year follow-up period. Twenty-three men (mean age at baseline 28.6 years) with childhood-onset GH deficiency were studied during a 10-year period of GH substitution. Memory tasks, mood questionnaires, and IGF-I values were obtained at baseline and after 0.5, 1, 2, 3, 5, and 10 years of GH substitution. Both mood and memory improved during GH therapy. After 6 months of treatment, anxiety and tension were reduced and vigor had improved. Memory improved after 1 year of substitution. These improvements were maintained during the 10-year follow-up period. Higher intra-subject IGF-I levels were associated with better mood (anxiety, tension, vigor). This study shows that 10 years of GH therapy is beneficial in terms of well-being and cognitive functioning in childhood-onset GH-deficient men. It may be concluded that once the decision to start GH treatment has been taken, this may imply that GH therapy has to be continued for a long period to maintain the psychological improvements and to prevent a relapse.  相似文献   
184.
神经营养因子(NTFs)是近几年神经科学研究的热点,研究显示它在神经系统中发挥独特的作用,尤其是神经生长因子(NGF)、脑源性神经营养因子(BDNF)在脑内功能及其表达调控方面具有重要作用。围绝经期妇女随着雌激素水平的降低会产生认知功能的减退,有研究发现去卵巢动物(OVX)雌激素水平降低可以导致某些NGF、BDNF的丢失。通过启动内源性NGF和BDNF的表达而实现对神经元的保护可能为雌激素替代治疗(ERT)脑保护作用的一种机制。本文就近几年的研究进展做一简要综述。  相似文献   
185.
目的:脑白质病变与老年认知功能障碍关系密切,尤其是深部白质病变更是血管性认知功能损害的常见危险因素,但临床上对于侧脑室旁白质病变与认知功能损害的关系研究较少,本研究旨在探讨侧脑室旁白质病变患者认知功能损害的特点。方法:选取2011年2月.2012年10月住院健康查体者159例,根据有无侧脑室旁白质病变分为脑白质病变组及对照组,根据侧脑室白质病变严重程度分为轻度组及中重度组。所有患者分别进行蒙特利尔认知评估表(MontrealCognitiveAssessment,MoCA)中文版、简易精神状态检查表(MiniMentalStateExamination,MMSE)和画钟测验(clockdrawingtest,CDT)评估。结果:脑白质病变组MMSE量表总分、CDT、MoCA量表总分及视空间、计算力、延迟回忆及空间执行功能分低于对照组,差异有统计学意义(P〈0.05);白质病变中重度组MMSE、MoCA量表总分及计算力得分低于轻度组,差异有统计学意义(P〈0.05)。结论:本研究显示侧脑室旁白质病变患者总体认知功能评分明显低于对照组,中重度患者的计算力下降尤为突出,提示我们侧脑室旁白质病变是导致患者总体认知功能下降及计算力损害的危险因素,临床上应该提高对于侧脑室旁白质病变的重视。  相似文献   
186.
使用工具曾被认为是人类独有的能力,然而,在过去的50年中,学界逐渐认识到工具的使用普遍存在于整个动物界。其中,使用工具最多的类群是哺乳类、鸟类和昆虫。动物使用工具有一定目标性,然而大多数动物仅考虑当前的目标,而非长远目标。动物使用工具的行为受到环境因素和动物自身认知能力、生理特点与进化历史的影响,并可能表现出一定的个体差异。有些动物使用工具的行为是与生俱来的,然而大部分高等动物通过试错学习获得使用工具的能力。通过模仿学习,一些使用工具的行为可以传播和演化,从而在种群中广泛分布。工具的使用是动物认知领域的核心概念之一,开展动物使用工具的研究,能够加深对动物认知能力和行为进化的理解。  相似文献   
187.
目的:了解临床医师对电子病历书写的态度和行为现状以及电子病历管理和对医疗质量的认知等情况,为制定科学的电子病历管理方案提供借鉴。方法:选取两所2所三级甲等和2所三级乙等医院临床医师共计450名进行调查,采用问卷调查医师对电子病例相关知识(如临床医师对电子病例相关法规认知、电子病例监控对电子病历影响及电子病历优点等)的认知和需求。结果:临床医师电子病历总体书写现状调查显示,对于书写电子病历中相似的部分,48.7%(219例)的医师直接复制粘贴再修改;复制粘贴使用比率≥40%占76.7%(345例);电子病历书写出错原因主要为认为责任心不强(38.2%)和病历系统掌握不到位(29.6%);促进临床医师按要求写好病历的主要动力为法律证据(32.9%)和培养临床思维(49.1%);54.9%(247例)医师能对自己的病历进行经常检查;科室负责人对电子病历经常检查的占33.1%(149例);50%左右人员对电子病历系统操作掌握情况一般;79.33%的临床医师认为电子病历的使用有助于提高医疗质量;临床医师认为电子病历对医疗质量的影响主要是提高病历书写速率、病历完成及时性、管理系统性、病历安全性和患者满意度。结论:临床医师在电子病历书写中复制粘贴比例较高,且对相关的法律法规认识一般,对医院电子病历系统掌握不熟悉,应加大相关内容的培训,更有利于医院电子病历的管理。  相似文献   
188.
许多研究认为,不同个体的认知能力存在差异,同一个体的多种认知表现之间可能存在关联。然而,目前对动物认知表现关联的研究结果存在诸多矛盾和争议。本研究以虎皮鹦鹉(Melopsittacus undulatus)为研究对象,通过自我控制、联想学习和反转学习三项认知实验,探究三项表现的联系。实验结果发现,在虎皮鹦鹉中,联想学习表现越好,反转学习亦表现越好。个体对实验装置的新异恐惧(对新环境或新事物的恐惧)越弱,自我控制表现越好。雌、雄个体在三项认知实验中的表现没有显著差异。综上所述,虎皮鹦鹉的一些认知能力存在关联,这暗示了虎皮鹦鹉中可能存在一般认知能力(“g”)。新异恐惧与自我控制表现的强烈相关,说明了勇敢程度可能会影响认知表现。  相似文献   
189.
Diabetic patients are at increased risk to develop cognitive deficit and senile dementia. This study was planned to assess the benefits of chronic carnosine administration on prevention of learning and memory deterioration in streptozotocin (STZ)-diabetic rats and to explore some of the involved mechanisms. Rats were divided into 5 groups: i.e., control, carnosine100-treated control, diabetic, and carnosine-treated diabetics (50 and 100 mg/kg). Carnosine was injected i.p. at doses of 50 or 100 mg/kg for 7 weeks, started 1 week after induction of diabetes using streptozotocin. Treatment of diabetic rats with carnosine at a dose of 100 mg/kg at the end of the study lowered serum glucose, improved spatial recognition memory in Y maze, improved retention and recall in elevated plus maze, and prevented reduction of step-through latency in passive avoidance task. Furthermore, carnosine at a dose of 100 mg/kg reduced hippocampal acetylcholinesterase (AChE) activity, lowered lipid peroxidation, and improved superoxide dismutase (SOD) activity and non-enzymatic antioxidant defense element glutathione (GSH), but not activity of catalase. Meanwhile, hippocampal level of nuclear factor-kappaB (NF-κB), tumor necrosis factor α (TNF-α), and glial fibrillary acidic protein (GFAP) decreased and level of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase 1 (HO-1) increased upon treatment of diabetic group with carnosine at a dose of 100 mg/kg. Taken together, chronic carnosine treatment could ameliorate learning and memory disturbances in STZ-diabetic rats through intonation of NF-κB/Nrf2/HO-1 signaling cascade, attenuation of astrogliosis, possible improvement of cholinergic function, and amelioration of oxidative stress and neuroinflammation.  相似文献   
190.
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