目的采用静息态分数低频振幅(fractional amplitude of low frequency fluctuations,fALFF)技术结合精神运动警觉性实验(psychomotor vigilance task,PVT),探讨高温诱发人脑脑力疲劳的神经活动变化及意义。方法 20名被试按随机交叉顺序...目的采用静息态分数低频振幅(fractional amplitude of low frequency fluctuations,fALFF)技术结合精神运动警觉性实验(psychomotor vigilance task,PVT),探讨高温诱发人脑脑力疲劳的神经活动变化及意义。方法 20名被试按随机交叉顺序先进行生理参数(心率、呼吸率、血压、直肠温度)测量,再进行PVT测试,之后在高温(50℃)与常温(25℃)下暴露1h,并采集功能磁共振(functional magnetic resonance imaging,fMRI)数据,扫描结束后继续监测生理数据,待恢复到正常时再次进行PVT测试。fMRI数据采用fALFF分析,分别对其进行配对t检验。并对fALFF有显著变化的区域与PVT测试反应时做相关分析。结果行为学结果显示高温组实验后的PVT测试反应时较常温组显著延长。fALFF分析显示双侧丘脑、右尾状核、左壳核、左侧岛叶、左侧海马回等脑区fALFF值显著增高而双侧额中回、左侧额上回、右侧扣带回显著降低,其中右侧额中回、右侧扣带回与热暴露后的组间PVT反应时差值显著相关。结论高温后PVT测试反应时的增加,反映了高温诱发人脑脑力疲劳现象的存在,而静息态成像模式变化,进一步揭示了高温下人脑脑力疲劳神经学基础。展开更多
Objective To observe the clinical application value of total free-breathing cardiac MR(CMR)examination preliminarily.Methods Two patients who underwent CMR scanning under free-breathing state,including cine,motion cor...Objective To observe the clinical application value of total free-breathing cardiac MR(CMR)examination preliminarily.Methods Two patients who underwent CMR scanning under free-breathing state,including cine,motion correction T1 and T2 mapping,blood flow imaging,and late gadolinium enhancement scanning were retrospectively enrolled,and the qualities of the above images were evaluated and compared with that of conventional CMR images under breath-holding state.Results No significant difference of imaging quality was found between total free-breathing and conventional breath-holding CMR.The differences of left ventricular ejection fraction,cardiac output,left ventricular end-diastolic volume index and left ventricular mass measured based on CMR images under different breath conditions were limited.Conclusion Total free-breathing CMR was feasible in clinical practice,which could provide"one-stop"evaluation of cardiac structure,function and myocardial histological characteristics,hence having promising clinical prospects.展开更多
文摘目的采用静息态分数低频振幅(fractional amplitude of low frequency fluctuations,fALFF)技术结合精神运动警觉性实验(psychomotor vigilance task,PVT),探讨高温诱发人脑脑力疲劳的神经活动变化及意义。方法 20名被试按随机交叉顺序先进行生理参数(心率、呼吸率、血压、直肠温度)测量,再进行PVT测试,之后在高温(50℃)与常温(25℃)下暴露1h,并采集功能磁共振(functional magnetic resonance imaging,fMRI)数据,扫描结束后继续监测生理数据,待恢复到正常时再次进行PVT测试。fMRI数据采用fALFF分析,分别对其进行配对t检验。并对fALFF有显著变化的区域与PVT测试反应时做相关分析。结果行为学结果显示高温组实验后的PVT测试反应时较常温组显著延长。fALFF分析显示双侧丘脑、右尾状核、左壳核、左侧岛叶、左侧海马回等脑区fALFF值显著增高而双侧额中回、左侧额上回、右侧扣带回显著降低,其中右侧额中回、右侧扣带回与热暴露后的组间PVT反应时差值显著相关。结论高温后PVT测试反应时的增加,反映了高温诱发人脑脑力疲劳现象的存在,而静息态成像模式变化,进一步揭示了高温下人脑脑力疲劳神经学基础。
文摘Objective To observe the clinical application value of total free-breathing cardiac MR(CMR)examination preliminarily.Methods Two patients who underwent CMR scanning under free-breathing state,including cine,motion correction T1 and T2 mapping,blood flow imaging,and late gadolinium enhancement scanning were retrospectively enrolled,and the qualities of the above images were evaluated and compared with that of conventional CMR images under breath-holding state.Results No significant difference of imaging quality was found between total free-breathing and conventional breath-holding CMR.The differences of left ventricular ejection fraction,cardiac output,left ventricular end-diastolic volume index and left ventricular mass measured based on CMR images under different breath conditions were limited.Conclusion Total free-breathing CMR was feasible in clinical practice,which could provide"one-stop"evaluation of cardiac structure,function and myocardial histological characteristics,hence having promising clinical prospects.
