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1.
人际关系影响竞争情境下结果评价的ERP证据   总被引:1,自引:0,他引:1  
为了研究竞争情境下人际关系影响结果评价的认知神经机制,记录16名健康成人进行扑克大小游戏时的脑电波,分析被试与朋友以及与陌生人竞争时输赢反馈的ERP.在竞争情境下,人际关系对与结果评价有关的反馈负波(FRN)和P300两个成分都有影响.和朋友竞争的FRN波幅比和陌生人竞争的FRN波幅大,表明FRN除了反映对结果输赢的快速评价,还可能反映了由竞争所引起的认知冲突,和朋友竞争引发更大的认知冲突.和陌生人竞争的P300波幅比和朋友竞争的P300波幅大,表明P300可能反映了一种晚期和社会性注意分配以及动机/情感有关的自上而下的结果评价过程.  相似文献   

2.
目的应用免疫组化技术和电生理技术记录心肌细胞/胶原复合体对心梗大鼠梗死周边区的有效不应期(ERP)及缝隙连接蛋白43(Cx43)改变,探讨梗死周边区的电偶联网络变化。方法将成年SD大鼠随机分组:假手术组、模型组、移植组。后2组制作心肌梗死动物模型,假手术组仅开胸,不结扎冠状动脉,移植组移植心肌细胞与胶原材料复合组织。结果①左室ERP变化:与假手术组相比,心梗组梗死周边区ERP显著延长(P〈0.01);移植组梗死周边区ERP延长,但较心梗阻ERP缩短,差异无显著性(P〉0.01)。②Cx43免疫组化结果:移植组Cx43阳性蛋白表达高于心梗组。结论移植的心肌细胞/胶原复合体移植可改善大鼠心肌梗死周边区缝隙连接电偶联网络,进而调控心肌细胞/胶原复合体与宿主心肌同步收缩。  相似文献   

3.
采用事件相关电位(ERP)技术探讨了被试完成地震色词Stroop任务(the earthquake color-matching Stroop task)时的脑内时程动态变化.24名被试都亲身经历了汶川大地震(5.12),其中12名被试为成都灾民(成都组:强烈震感),另外12名来自重庆(重庆组:稍有震感).行为结果发现,只有成都组被试对地震相关词颜色判断的反应时显著长于地震无关词,表现出了明显的地震干扰效应(the earthquake interference effect).ERP结果显示,就成都组被试而言,在刺激出现后的350~450ms内,地震相关词比无关词诱发出一个更加正性的ERP成分(P350~450),最强效应出现在大脑中前部;而重庆组没有表现出明显的ERP干扰效应.对差异波(地震相关词一地震无关词)进行偶极子溯源分析,结果显示,P350~450可能起源于海马旁回.本研究结果表明,P350~450可能反映了成都被试对地震词的注意加工偏向(或创伤性事件的自动激活),从而干扰了其对刺激物理颜仁的判断.  相似文献   

4.
图形形状和空间位置知觉的ERP研究   总被引:2,自引:0,他引:2  
研究图形表状和空间位置知觉任务与单纯图形形状知觉任务所诱发的ERP反应,探讨同时注意物体的两种不同特征是与仅注意其中一种特征时的ERP特性与差别。实验结果为:(1)行为数据显示,两种任务的正确率没有显著差别,但形状和空间位置知觉任务的反应时显著低于单纯形状知觉任务;(2)ERP数据显示,两种任务表现出非常相近的ERP波形特征;在大脑后部区域微弱的P1成分,非常显著的N1成分,显著的P2,N2,P3成分;在大脑前部额区显著的P2成分,并且,与单纯形状知觉任务相比,图形形状和空间位置知觉任务表现枕颞区N2波幅的显著减弱,P3潜伏期的显著缩短,额区的P2波幅的显微减弱;(3)脑电表图与分辨率断层成象(LORETA)显示,两种任务的特征波N1成分均来源于双侧的枕颞皮层,表明两种任务均涉及到与物体形状识别相关的视皮层腹侧通路,而差别波dN2成分来源于在侧枕颞区,暗示特征加工的差异主要发生在左侧枕颞区。  相似文献   

5.
目的:探讨头孢曲松通过抑炎通路发挥神经保护作用的机制。方法:45只雄性sD大鼠,随机分为3组(n=15),预处理组在大鼠大脑中动脉阻断(MCAo)前5d每日给予腹腔注射头孢曲松缓冲液(200mg/kg),观察局灶性脑缺血2h再灌注24h后,各组间大鼠神经行为学评分、脑梗死容积变化、小胶质细胞和IL-1β的数量变化。结果:再灌注24h后,头孢曲松预处理组可改善大鼠神经行为学评分和脑梗死面积(P〈0.05),小胶质细胞活化数量减少(P〈0.05),ELISA检测IL-1β分泌数量有显著下降趋势,但无统计学差异(P=0.18)。结论:头孢曲松可以部分抑制小胶质细胞活化,减少IL-1β释放发挥神经保护作用。  相似文献   

6.
目的:探讨7-9岁高功能自闭症儿童面孔加工时事件相关电位(Electrical event-relateds,ERP)的变化及其意义。方法:选择7-9岁自闭症儿童(实验组)与普通儿童(对照组)各15名,以中国人中性面孔及常见物件为刺激材料,记录和比较两类儿童在面孔刺激下的脑电成分。结果:剔除无效数据后,有效被试:实验组12人、对照组14人,两组年龄和性别组成无显著性差异(P〉0.05)。而,自闭症组按键反应时间、面孔反应时间显著长于对照组(按键反应F=9.26,P〈0.05;面孔反应t=5.32,P〈0.05)。在面孔刺激因素下,自闭症组平均波峰明显小于对照组(t=4.62,P〈0.05)。在物件刺激因素下,两组平均波峰无显著差异(t=0.21,P〉0.05)。而两组的潜伏期组别主效应不显著(F=1.63,P〉0.05)。结论:自闭症儿童面孔结构编码过程异常,对面孔的关注度比普通儿童低。本文证实了自闭症儿童知觉/认知缺陷的存在,为更进一步研究提供了理论依据。  相似文献   

7.
目的:观察老年人和年轻人的内源性注意行为学及事件相关电位(ERP)表现,探讨老龄化对内源性注意的影响及其机制。方法:参考Posner的经典的"cue-target"范式设计内源性注意任务,分别记录和分析年轻人和老年人行为学和事件相关电位波形P1、N1,比较老年人和年轻人在内源性注意任务中的不同表现。结果:在内源性注意条件下,年轻人的反应时明显短于老年人(P0.05),对于N1成分的波幅,年龄主效应显著(P0.05),年轻人较老年人诱发更大的N1波幅。对于N1成分的潜伏期,年龄主效应显著(P0.05),年轻人潜伏期明显短于老年人。结论:老龄化对内源性注意的早期阶段有影响,在提高老年人注意力时应当对注意的不同类型进行评估和分类以采取合适的治疗策略。  相似文献   

8.
一体化病证结合帕金森病大鼠模型中医证候属性研究   总被引:1,自引:0,他引:1  
目的探讨6-OHDA帕金森病(PD)大鼠模型的中医证候属性。方法 采用经典的6-羟基多巴胺损毁注射法制作PD模型,随机分为模型组和药物治疗组,并分别采用天麻钩藤饮、桃红四物汤和涤痰汤进行反证治疗,同时设立正常对照组、假手术组。分别观察各组动物的神经行为学、舌象、氧化应激、环核苷酸、血管活性物质等的变化,从症状(行为学和舌象)、药物治疗反证、客观检测指标等方面对6-羟基多巴胺制作的PD模型进行综合分析,评价该模型的中医证候属性。结果(1)舌象:PD模型大鼠显微舌象分析结果为红舌。(2)行为学方面:PD模型大鼠的旋转圈数明显升高,与各药物组比较,差异均有显著性(P〈0.01);天麻钩藤饮与桃红四物汤组、涤痰汤组比较,差异亦均有显著性(P〈0.05),而桃红四物汤组与涤痰汤组差异无显著性(P〉0.05)。(3)客观指标:与正常对照组、假手术组比较,PD模型组MDA、cAMP、ET、TXB2含量明显升高,SOD、GSH、GSH-Px、cGMP、6-keto-PGF1α含量下降(P〈0.01);天麻钩藤饮可明显降低MDA、cAMP、ET、TXB2(P〈0.05或P〈0.01),升高SOD、GSH、GSH-Px、cGMP、6-keto-PGF1α(P〈0.01),桃红四物汤组、涤痰汤可升高SOD、GSH、GSH-Px(P〈0.05,或P〈0.01),降低cAMP(P〈0.05)、ET(P〈0.01)。天麻钩藤饮与涤痰汤组在SOD、GSH、cGMP,与桃红四物汤组在SOD、GSH、GSH-Px、cGMP、6-keto-pgf1α、TXB2,差异有显著性(P〈0.05,或P〈0.01)。涤痰汤组与桃红四物汤组TXB2(P〈0.05),余各指标间差异无显著性(P〉0.05)。结论 6-羟基多巴胺制作的PD大鼠模型的中医证候属性属于阴虚动风证。  相似文献   

9.
摘要 目的:观察低频重复经颅磁刺激(rTMS)联合艾司西酞普兰对广泛性焦虑障碍(GAD)患者生活质量及事件相关电位P300的影响。方法:采用随机数字表法,将2019年2月~2021年1月期间我院收治的120例GAD患者分为对照组(艾司西酞普兰治疗)和研究组(对照组的基础上接受低频rTMS治疗),各为60例。观察并对比两组疗效和不良反应,记录两组生活质量及事件相关电位P300的变化。结果:研究组的临床总有效率高于对照组(P<0.05)。研究组治疗2个月后P300潜伏期短于对照组,P300波幅长于对照组(P<0.05)。研究组治疗2个月后疼痛、生理职能、精神健康、生理功能、躯体精力、情感职能、社会功能、总体健康各维度评分高于对照组(P<0.05)。两组治疗2个月后汉密尔顿焦虑量表(HAMA)评分较治疗前下降,且研究组低于对照组(P<0.05)。两组不良反应发生率对比无统计学差异(P>0.05)。结论:低频rTMS联合艾司西酞普兰治疗GAD患者,可有效改善其焦虑症状,提高生活质量,促进认知功能恢复,具有显著的临床疗效。  相似文献   

10.
目的:探讨雾化吸入糖皮质激素治疗慢性阻塞性肺病急性加重期(AECOPD)的临床效果。方法:60例AECOPD患者随机分为治疗组和对照组,对照组给予抗感染、吸氧、化痰等常规治疗,治疗组在常规治疗的基础上给予糖皮质激素雾化吸入治疗,连续治疗14d后评价临床疗效,观察治疗前后两组患者的临床症状和肺功能改善情况。结果:治疗组临床疗效有效率为96.7%,高于对照组(80.0%),相比较有显著性差异(P〈0.05);治疗组临床症状评分和呼吸困难评分与治疗前和对照组比较显著下降,相比较有显著性差异(P〈0.05);治疗组FEV1、FEV水平与治疗前和对照组比较显著上升,肺功能改善显著,相比较有显著性差异(P〈0.05)。结论:雾化吸入糖皮质激素治疗AECOPD疗效肯定,值得临床推广应用  相似文献   

11.
To study how conserved fundamental concepts of the heat stress response (HSR) are in photosynthetic eukaryotes, we applied pharmaceutical and antisense/amiRNA approaches to the unicellular green alga Chlamydomonas reinhardtii. The Chlamydomonas HSR appears to be triggered by the accumulation of unfolded proteins, as it was induced at ambient temperatures by feeding cells with the arginine analog canavanine. The protein kinase inhibitor staurosporine strongly retarded the HSR, demonstrating the importance of phosphorylation during activation of the HSR also in Chlamydomonas. While the removal of extracellular calcium by the application of EGTA and BAPTA inhibited the HSR in moss and higher plants, only the addition of BAPTA, but not of EGTA, retarded the HSR and impaired thermotoler- ance in Chlamydomonas. The addition of cycloheximide, an inhibitor of cytosolic protein synthesis, abolished the attenu- ation of the HSR, indicating that protein synthesis is necessary to restore proteostasis. HSP90 inhibitors induced a stress response when added at ambient conditions and retarded attenuation of the HSR at elevated temperatures. In addition, we detected a direct physical interaction between cytosolic HSP90A/HSP70A and heat shock factor 1, but surprisingly this interaction persisted after the onset of stress. Finally, the expression of antisense constructs targeting chloroplast HSP70B resulted in a delay of the cell's entire HSR, thus suggesting the existence of a retrograde stress signaling cascade that is desensitized in HSP7OB-antisense strains.  相似文献   

12.
To accommodate two seemingly contradictory biological roles in plant physiology, providing both the rigid structural support of plant cells and the adjustable elasticity needed for cell expansion, the composition of the plant cell wall has evolved to become an intricate network of cellulosic, hemicellulosic, and pectic polysaccharides and protein. Due to its complexity, many aspects of the cell wall influence plant cell expansion, and many new and insightful observations and technologies are forthcoming. The biosynthesis of cell wall polymers and the roles of the variety of proteins involved in polysaccharide synthesis continue to be characterized. The interactions within the cell wall polymer network and the modification of these interactions provide insight into how the plant cell wall provides its dual function. The complex cell wall architecture is controlled and organized in part by the dynamic intracellular cytoskeleton and by diverse trafficking pathways of the cell wall polymers and cell wall-related machinery. Meanwhile, the cell wall is continually influenced by hormonal and integrity sensing stimuli that are perceived by the cell. These many processes cooperate to construct, maintain, and manipulate the intricate plant cell wall--an essential structure for the sustaining of the plant stature, growth, and life.  相似文献   

13.
Citrate synthase has a key role in the tricarboxylic (TCA) cycle of mitochondria of all organisms, as it cata- lyzes the first committed step which is the fusion of a carbon-carbon bond between oxaloacetate and acetyl CoA. The regulation of TCA cycle function is especially important in plants, since mitochondrial activities have to be coordinated with photosynthesis. The posttranslational regulation of TCA cycle activity in plants is thus far almost entirely unexplored. Although several TCA cycle enzymes have been identified as thioredoxin targets in vitro, the existence of any thioredoxin-dependent regulation as known for the Calvin cycle, yet remains to be demonstrated. Here we have investigated the redox regulation of the Arabidopsis citrate synthase enzyme by site-directed mutagenesis of its six cysteine residues. Our results indicate that oxidation inhibits the enzyme activity by the formation of mixed disulfides, as the partially oxidized citrate synthase enzyme forms large redox-dependent aggregates. Furthermore, we were able to demonstrate that thioredoxin can cleave diverse intraas well as intermolecular disulfide bridges, which strongly enhances the activity of the enzyme. Activity measurements with the cysteine variants of the enzyme revealed important cysteine residues affecting total enzyme activity as well as the redox sensitivity of the enzyme.  相似文献   

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15.
The pH of intracellular compartments is essential for the viability of cells. Despite its relevance, little is known about the pH of these compartments. To measure pH in vivo, we have first generated two pH sensors by combining the improved-solubility feature of solubility-modified green fluorescent protein (GFP) (smGFP) with the pH-sensing capabil- ity of the pHluorins and codon optimized for expression in Arabidopsis. PEpHluorin (plant-solubility-modified ecliptic pHluorin) gradually loses fluorescence as pH is lowered with fluorescence vanishing at pH 6.2 and PRpHluorin (plant- solubility-modified ratiomatric pHluorin), a dual-excitation sensor, allowing for precise measurements. Compartment- specific sensors were generated by further fusing specific sorting signals to PEpHluorin and PRpHluorin. Our results show that the pH of cytosol and nucleus is similar (pH 7.3 and 7.2), while peroxisomes, mitochondrial matrix, and plastidial stroma have alkaline pH. Compartments of the secretory pathway reveal a gradual acidification, spanning from pH 7.1 in the endoplasmic reticulum (ER) to pH 5.2 in the vacuole. Surprisingly, pH in the trans-Golgi network (TGN) and mul- tivesicular body (MVB) is, with pH 6.3 and 6.2, quite similar. The inhibition of vacuolar-type H+-ATPase (V-ATPase) with concanamycin A (ConcA) caused drastic increase in pH in TGN and vacuole. Overall, the PEpHluorin and PRpHluorin are excellent pH sensors for visualization and quantification of pH in vivo, respectively.  相似文献   

16.
Aphis gossypii Glover shows obvious host specialization, with cucurbit- and cotton-specialized biotypes or host races in many regions. Because its annual natal hostcrops senesce earlier the cucurbit-specialized biotype may suffer food deficiency. The method this biotype uses to overcome this challenge is still poorly understood. In orderto understand the potential of the cucurbit-specialized biotype aphids in host shift and usage, the performance of this biotype on cotton (Gossypium hirsutum), a common butpoor quality host plant, was explored in this study. The cucurbit-specialized aphids could establish populations on cotton only when these plants had at least nine leaves, and subsequent populations developed rather slowly. The presence of whitefly populations on cotton improved the success rate of cucurbit-specialized aphids. The cucurbit-specialized aphidswere mainly distributed on the older leaves of cotton, with only a few settling on the upper leaves. The cucurbit-specialized aphids reared on cotton for 40, 54 and 61 days stillmaintained strong preference for their natal host plant, cucumber (Cucumis sativus), rather than cotton, and their net reproductive rates and intrinsic rates of natural increase weredramatically lower when they were transferred onto new six-leaf cotton plants or detached leaves. Therefore, we concluded that the cucurbit-specialized aphids have the potentialto utilize mature or whitefly-stressed cotton plants, but that this feeding experience on cotton did not alter their specialization for cucurbits. Some cotton plants could act as atemporary host for the cucurbit-specialized aphids to overcome food deficiency arising from senescing cucurbits.  相似文献   

17.
The development of a plant leaf is a meticulously orchestrated sequence of events producing a complex organ comprising diverse cell types. The reticulate class of leaf variegation mutants displays contrasting pigmentation between veins and interveinal regions due to specific aberrations in the development of mesophyll cells. Thus, the reticulate mutants offer a potent tool to investigate cell-type-specific developmental processes. The discovery that most mutants are affected in plastid-localized, metabolic pathways that are strongly expressed in vasculature-associated tis- sues implicates a crucial role for the bundle sheath and their chloroplasts in proper development of the mesophyll cells. Here, we review the reticulate mutants and their phenotypic characteristics, with a focus on those in Arabidopsis thali- ana. Two alternative models have been put forward to explain the relationship between plastid metabolism and meso- phyll cell development, which we call here the supply and the signaling hypotheses. We critically assess these proposed models and discuss their implications for leaf development and bundle sheath function in C3 species. The characteriza- tion of the reticulate mutants supports the significance of plastid retrograde signaling in cell development and highlights the significance of the bundle sheath in C3 photosynthesis.  相似文献   

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19.
Proper vesicle tethering and membrane fusion at the cell plate are essential for cytokinesis. Both the vesicle tethering complex exocyst and membrane fusion regulator KEULE were shown to function in cell plate formation, but the exact mechanisms still remain to be explored. In this study, using yeast two-hybrid (Y-2-H) assay, we found that SEC6 interacted with KEULE, and that a small portion of C-terminal region of KEULE was required for the interaction. The direct SEC6-KEULE interaction was supported by further studies using in vitro pull-down assay, immunoprecipitation, and in vivo bimolecular florescence complementation (BIFC) microscopy, sec6 mutants were male gametophytic lethal as reported; however, pollen-rescued sec6 mutants (PRsec6) displayed cytokinesis defects in the embryonic cells and later in the leaf pavement cells and the guard cells. SEC6 and KEULE proteins were co-localized to the cell plate during cytokine- sis in transgenic Arabidopsis. Furthermore, only SEC6 but not other exocyst subunits located in the cell plate interacted with KEULE in vitro. These results demonstrated that, like KEULE, SEC6 plays a physiological role in cytokinesis, and the SEC6-KEULE interaction may serve as a novel molecular linkage between arriving vesicles and membrane fusion machin- ery or directly regulate membrane fusion during cell plate formation in plants.  相似文献   

20.
Reactive oxygen species and auxin play important roles in the networks that regulate plant development and morphogenetic changes, However, the molecular mechanisms underlying the interactions between them are poorly understood. This study isolated a mas (More Axillary Shoots) mutant, which was identified as an allele of the mitochondrial AAA-protease AtFtSH4, and characterized the function of the FtSH4 gene in regulating plant development by medi- ating the peroxidase-dependent interplay between hydrogen peroxide (H2Oz) and auxin homeostasis. The phenotypes of dwarfism and increased axillary branches observed in the mas (renamed as ftsh4-4) mutant result from a decrease in the IAA concentration. The expression levels of several auxin signaling genes, including IAA1, IAA2, and IAA3, as well as several auxin binding and transport genes, decreased significantly in ftsh4-4 plants. However, the H202 and peroxidases levels, which also have IAA oxidase activity, were significantly elevated in ftsh4-4 plants. The ftsh4-4 phenotypes could be reversed by expressing the iaaM gene or by knocking down the peroxidase genes PRX34 and PRX33. Both approaches can increase auxin levels in the ftsh4-4 mutant. Taken together, these results provided direct molecular and genetic evidence for the interaction between mitochondrial ATP-dependent protease, H2O2, and auxin homeostasis to regulate plant growth and development.  相似文献   

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