首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 204 毫秒
1.
目的利用AX型连续操作测试(AX-CPT)和事件相关电位(ERP)时空模式探讨上下文加工的任务概率效应及其脑机制。方法在AX-CPT任务中,18名大学生仅要求针对反应线索A后的反应探针X按键,而对抑制线索B后的各类探针X或Y均不反应。设立3组互补的AX型/AY型任务概率:0.55/0.15,0.35/0.35,0.15/0.55;保持BX型和BY型任务概率恒定,均为0.15。行为绩效和ERP数据分别采用单因素重复测量方差分析。结果反应线索A概率愈高,AX型反应愈快且BX型虚警愈多。ERP的F值统计参数映像显示概率效应显著脑区和时段分别是:线索A:顶中央区(300~350 ms)与左枕区(450~500 ms);线索B:右前额(350~500 ms)和左前额(750~950 ms)。AX型探针:右额顶(200~250 ms)、左额极、右背前额及双顶区(300~400 ms)和双顶枕区(400~650 ms);AY型探针:额中央区(350~500 ms)-P3效应;BX型探针:右颞区及左枕区(300~350 ms);BY型探针:左颞区(150~250 ms)。结论任务概率不仅影响反应型线索编码和抑制型线索期待,而且分别调节了四种类型探针加工相关的神经集群。  相似文献   

2.
目的 探讨面孔表情诱发的事件相关电位(ERP)时空模式特点。方法 25名受试者从事简笔画面孔表情识别任务。实验采用单因素(三水平:正性、中性、负性表情)重复测量析因设计和双侧配对t检验进行逐对比较(Bonferroni校正),利用统计参数映像呈现结果。结果 显著的表情效应分别于3个时段出现在不同的头皮区域:后顶区和双枕区(280~340ms),左额区(400~420ms)和右额区(480~500ms)。正性与中性表情的差异分别于4个时段相继出现在不同的头皮区域:右额顶颞区和左前额区(60~80ms),右枕区(120~140ms),左枕区(280~-320ms)和左额顶区(400~440ms)。负性与中性表情的差异分别于5个时段相继出现在不同的头皮区域:右枕区(120~140ms),中央额顶区(220~240ms),中央顶区(280~300ms),左顶和右额颞区(320~340ms)和额顶枕颞区(480~-500ms)。结论 面孔表情加工是涉及广泛脑区的动态演化过程,不同情绪的脑加工通路是不同的。  相似文献   

3.
目的 探讨面孔表情诱发的事件相关电位(ERP)时空模式特点。方法 25名受试者从事简笔画面孔表情识别任务。实验采用单因素(三水平:正性、中性、负性表情)重复测量析因设计和双侧配对t检验进行逐对比较(Bonferroni校正),利用统计参数映像呈现结果。结果 显著的表情效应分别于3个时段出现在不同的头皮区域:后顶区和双枕区(280-340ms).左额区(400-420ms)和右额区(480-500ms)。正性与中性表情的差异分别于4个时段相继出现在不同的头皮区域:右额顶颞区和左前额区(60-80ins),右枕区(120-140ms),左枕区(280-320ms)和左额顶区(400~440ms)。负性与中性表情的差异分别于5个时段相继出现在不同的头皮区域:右枕区(120~140ms),中央额顶区(220~240ms),中央顶区(280-300ms),左顶和右额颞区(320-340ins)和额顶枕颞区(48~500ms)。结论 面孔表情加工是涉及广泛脑区的动态演化过程。不同情绪的脑加工通路是不同的。  相似文献   

4.
目的考察神游的神经机制。方法 10名被试从事持续注意反应任务(SART)。两类视觉刺激分别以罕发与频发概率混合呈现,神游状态出现以罕发刺激的错误反应为依据,比较两种状态(神游有/无)下频发刺激引出的19通道事件相关电位(ERP)和行为绩效。采用(神游状态:有,无)×(罕发/频发概率:0.1/0.9,0.2/0.8,0.3/0.7)两因素重复测量设计。结果反应时间的概率效应显著:0.1/0.9组(460.54±46.46 ms)短于0.2/0.8组(485.42±47.23 ms)与0.3/0.7组(485.99±54.85ms),F(2,18)=14.083,P=0.000;神游的(468.82±48.74 ms)显著短于非神游(485.82±51.53 ms),F(1,9)=38.108,P=0.000。漏报率概率效应显著:0.1/0.9组[(24.61±11.65)%]高于0.2/0.8组[(19.94±9.94)%]与0.3/0.7组[(20.52±9.60)%],F(2,18)=4.924,P=0.020。感受性指标d’无显著概率效应。ERP的F值参数映像显示概率与神游交互效应出现在双侧顶区(500~600 ms);概率效应出现在左前额和右顶区(300~350 ms)以及双额区(800~900 ms);神游效应主要出现在3个时段:感知觉阶段(150~350 ms)双侧枕区和额极(250~300 ms);判断与决策阶段(400~600 ms)的双侧额颞顶区;反应监控阶段(800~900 ms)的双侧额区。结论在神游阶段,外源信息的认知加工活动整体上削弱,反应虽加速但更易出错。神游可能系执行注意系统的监控失败所致。SART的刺激概率结构通过执行注意系统影响外源性信息加工。  相似文献   

5.
目的 考察情绪Stroop实验范式的事件相关电位(ERP)时空模式.方法 13名受试者从事情感词汇的颜色判别任务,同时记录其19通道的ERP,实验采用单因素三水平(情绪词效价:正性、中性、负性)重复测量析因设计,ERP分析结果利用F值的统计参数映像呈现.结果 行为指标反应时间和反应正误率均无显著差异.ERP的F值参数映射示显著情感效应主要出现在3个时段:枕区(200~220 ms);左前额及中央额区(270~300 ms);枕顶区(左560~580 ms、右620~630 ms).结论 任务无关的情绪词加工在不同阶段涉及广泛脑区,ERP在情绪研究和评价方面比行为指标更为敏感.  相似文献   

6.
摘要:目的利用AX型连续操作测试(AX-CPT)和事件相关电位(ERP)时空模式探讨上下文加工的任务概率效应及其脑机制。
方法在AX-CPT任务中,18名大学生仅要求针对反应线索A后的反应探针X按键,而对抑制线索B后的各类探针X或Y均不
反应。设立3组互补的AX型/AY型任务概率:0.55/0.15,0.35/0.35,0.15/0.55;保持BX型和BY型任务概率恒定,均为0.15。行
为绩效和ERP数据分别采用单因素重复测量方差分析。结果反应线索A概率愈高,AX型反应愈快且BX型虚警愈多。ERP
的F值统计参数映像显示概率效应显著脑区和时段分别是:线索A:顶中央区(300~350 ms)与左枕区(450~500 ms);线索B:右
前额(350~500 ms)和左前额(750~950 ms)。AX型探针:右额顶(200~250 ms)、左额极、右背前额及双顶区(300~400 ms)和双顶
枕区(400~650 ms);AY型探针:额中央区(350~500 ms)-P3效应;BX型探针:右颞区及左枕区(300~350 ms);BY型探针:左颞区
(150~250 ms)。结论任务概率不仅影响反应型线索编码和抑制型线索期待,而且分别调节了四种类型探针加工相关的神经集群。
  相似文献   

7.
目的 探索认知灵活性相关脑网络的动态演化.方法 采用交替切换任务范式,23名被试完成数字大小和奇偶判断任务,每3个试次数字颜色改变,提示任务规则切换,3个试次分别对应切换、基线和准备条件.分析3种条件下的行为绩效和19通道事件相关电位统计参数映像的时空模式.结果 切换代价(切换-基线)显著:反应时123.61±83.84 ms;正确率(1.24±3.30)%.事件相关电位统计参数映像(t)显示:切换效应先后出现在额顶网络的右侧和左侧部分,准备效应主要表现为反应前右侧额极和反应后左侧额极的激活.结论 认知灵活性主要依赖于额顶网络的动态激活,而前额极参与任务切换前的跨试次准备过程;背侧额区参与试次内的即时任务切换,且左右两侧额区功能不同.  相似文献   

8.
目的 运用事件相关电位(event-related potentials, ERP)探讨顺序及计数任务加工的脑机制.方法 16名大学生针对呈现的双字母和参考数字图片分别完成字母顺序判断任务和字母间距与参考数字比较的计数任务, 同时记录其19通道ERP.采用2(任务:顺序、计数)×3(字母间距:1、2、3)两因素重复测量析因设计,ERP分析结果利用F值和t值的统计参数映像呈现.结果 顺序任务的反应时间显著短于计数任务[F (1, 15)=502.43,P =0.00],前者正确率显著低于后者[F (1, 15)=52.96,P =0.00].计数任务行为绩效存在显著距离效应:三种字母间距的反应时间[(1710.6±176.6)ms,(2133.2±201.3)ms,(2437.3±198.9)ms]和正确率分别随字母间距加大而延长或降低.ERP统计参数映像显示:顺序任务的右前额颞和左额颞活动(350~800 ms)增强;计数任务的额顶网络活动(200~300 ms)增强,右顶颞活动(860~890 ms)与字母间距线性关联.结论 顺序任务比计数任务执行更快但更易出错.前者ERP效应提示右侧半球提取和利用左侧半球存贮的字母顺序知识,反映了从记忆直接提取答案策略.后者的额顶ERP效应提示工作记忆机制的参与,右顶颞区ERP效应反映字母间距离效应和计数策略的应用.  相似文献   

9.
目的 探讨运动意向的形成、执行和抑制过程的神经相关.方法 记录14名在校大学生在完成意向准备与执行两阶段任务时的19通道事件相关电位(event-related potentials,ERP)和行为反应.首先在意向准备阶段呈现"做什么"(what)线索,分为3类:(1)指令性或(2)自由性意向准备左手或右手按键反应,(3)对照情形无须意向准备.随后在意向执行阶段旱现"是否做"(whether)线索,受试者将(1)强制性或(2)自主性执行或放弃先前的运动意向.结果 平均反应时的"做什么"和"是否做"交互效应显著(F(2,26)=8.262,P=0.002).其中,指令意向条件下的强制反应[(466.60±106.38)ms]显著快于自主反应[(545.35±147.06)ms],自由意向条件下的强制反应[(538.71±127.39)ms]与自主反应[(561.44±146.51)ms]无显著差异,无意向准备(对照)条件下的强制反应[(533.80±81.71)ms]快于自主反应[(589.75±140.81)ms].在意向形成阶段,自由性和指令性的ERP效应主要出现在双额部(150~200ms)、广泛额顶部和右侧颞区(300~700 ms).在意向执行阶段,自主执行与自主抑制的ERP效应出现在左前额及额顶中央区(160~220 ms),右前额顶区(300~550 ms).结论 自由性运动意向产生于前额部,运动意向在额顶网络维持.早期的意向抑制涉及左前额及额顶中央区,而右额顶区与晚期的反应抑制相关.  相似文献   

10.
目的 利用事件相关电位(ERP)时空模式探讨视觉突出性目标加工的神经机制.方法 16名受试者执行视觉搜索任务,按键判定4个项目中是否存在1个目标,其中目标和1个分心物可能具备颜色突出性.行为绩效和ERP数据应用2(分心物突出性:有、无)×3(目标:缺失、低突出性、高突出性)双因素重复测量方差分析.结果 反应时间交互效应显著(F(1.99,29.79)=21.56,P=0.00).低突出性目标的搜索反应时间在分心物突出性存在[ (552.57 ±82.32) ms]和缺乏[(540.47±75.68)ms]条件下差异显著(t(15)=-2.489,P=0.025).高突出性目标的搜索反应时间在分心物突出性存在[(527.14±77.84) ms]和缺乏[(527.77±78.31)ms]条件下无显著差异(l(15)=0.162,P=0.873).ERP的F值统计参数映像提示:在知觉阶段(350 ~450 ms),分心物和目标的突出性效应分别出现在处理刺激新奇性的右额顶颞区和视觉加工相关的顶枕区,两者的交互效应存在于刺激熟悉性加工及分类相关的左颞区(450~ 600 ms).结论 高突出性目标的迅捷加工得益于早期其与分心物的并行处理以及后期左颞区熟悉性网络对其的有效分类.  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…  相似文献   

15.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

16.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

19.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

20.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号