目的:分析术后早期颅内压(ICP)参数预测高血压性脑出血(HICH)手术患者预后的价值。方法:根据术后6个月时的格拉斯哥预后量表(GOS)评分,将69例HICH患者分为预后良好组(出院后6个月GOS评分为4~5分,n=37)和预后不良组(出院后6个月GOS评分为...目的:分析术后早期颅内压(ICP)参数预测高血压性脑出血(HICH)手术患者预后的价值。方法:根据术后6个月时的格拉斯哥预后量表(GOS)评分,将69例HICH患者分为预后良好组(出院后6个月GOS评分为4~5分,n=37)和预后不良组(出院后6个月GOS评分为1~3分或随访期内死亡,n=32),回顾性分析两组患者术后1~3 d的ICP、压力反应指数(PRx)、平均颅内压波幅(MWA)、20 mm Hg阈值下颅内压剂量(Dicp20)。结果:预后不良组患者术后1 d的ICP、PRx、MWA、Dicp20等ICP参数均高于预后良好组(P<0.05)。术后早期ICP参数预测HICH手术患者预后的受试者工作特征曲线下面积(AUC)均有统计学意义(P<0.05),其中PRx的AUC最高,在Cut-off值下,Dicp20的灵敏度最高,Dicp20和MWA的特异度最高。结论:采用有创监测方法测定HICH患者术后早期ICP参数,可辅助预测患者的预后,临床医生应加强对患者术后早期ICP参数的监测和干预,从而达到改善预后的目的。展开更多
原子级分辨率的成像表征对探究材料结构与性质间的联系具有重大意义。应用像差校正的高分辨电子显微成像技术(high⁃resolution transmission electron microscopy,HRTEM)可以实现亚埃尺度分辨率的图像表征,但电子束辐照敏感材料受限于...原子级分辨率的成像表征对探究材料结构与性质间的联系具有重大意义。应用像差校正的高分辨电子显微成像技术(high⁃resolution transmission electron microscopy,HRTEM)可以实现亚埃尺度分辨率的图像表征,但电子束辐照敏感材料受限于辐照引起的结构损伤,无法用常规辐照剂量进行HRTEM成像表征。将出射波重构(exit wave reconstruction,EWR)技术应用于辐照敏感材料,一方面可以解决HRTEM图像中衬度反转的问题并提高图像分辨率至信息极限;另一方面,通过算法实现对信息的充分利用,适合于从低剂量数据中提取有效信息。采用低剂量EWR技术可以实现电子束敏感材料的原子级分辨率图像,为研究电子束辐照敏感材料提供更多可能性,也使针对出射波重构技术的研究具有更大的应用前景与科学意义。展开更多
In this study, we consider the heat-induced withdrawal reflex caused by exposure to an electromagnetic beam. We propose a concise dose-response relation for predicting the occurrence of withdrawal reflex from a given ...In this study, we consider the heat-induced withdrawal reflex caused by exposure to an electromagnetic beam. We propose a concise dose-response relation for predicting the occurrence of withdrawal reflex from a given spatial temperature profile. Our model is distilled from sub-step components in the ADT CHEETEH-E model developed at the Institute for Defense Analyses. Our model has only two parameters: the activation temperature of nociceptors and the critical threshold on the activated volume. When the spatial temperature profile is measurable, the two parameters can be determined from test data. We connect this dose-response relation to a temperature evolution model for electromagnetic heating. The resulting composite model governs the process from the electromagnetic beam deposited on the skin to the binary outcome of subject’s reflex response. We carry out non-dimensionalization in the time evolution model. The temperature solution of the non-dimensional system is the product of the applied power density and a parameter-free function. The effects of physical parameters are contained in non-dimensional time and depth. Scaling the physical temperature distribution into a parameter-free function greatly simplifies the analytical solution, and helps to pinpoint the effects of beam spot area and applied power density. With this formulation, we study the theoretical behaviors of the system, including the time of reflex, effect of heat conduction, biological latency in observed reflex, energy consumption by the time of reflex, and the strategy of selecting test conditions in experiments for the purpose of inferring model parameters from test data.展开更多
文摘目的:分析术后早期颅内压(ICP)参数预测高血压性脑出血(HICH)手术患者预后的价值。方法:根据术后6个月时的格拉斯哥预后量表(GOS)评分,将69例HICH患者分为预后良好组(出院后6个月GOS评分为4~5分,n=37)和预后不良组(出院后6个月GOS评分为1~3分或随访期内死亡,n=32),回顾性分析两组患者术后1~3 d的ICP、压力反应指数(PRx)、平均颅内压波幅(MWA)、20 mm Hg阈值下颅内压剂量(Dicp20)。结果:预后不良组患者术后1 d的ICP、PRx、MWA、Dicp20等ICP参数均高于预后良好组(P<0.05)。术后早期ICP参数预测HICH手术患者预后的受试者工作特征曲线下面积(AUC)均有统计学意义(P<0.05),其中PRx的AUC最高,在Cut-off值下,Dicp20的灵敏度最高,Dicp20和MWA的特异度最高。结论:采用有创监测方法测定HICH患者术后早期ICP参数,可辅助预测患者的预后,临床医生应加强对患者术后早期ICP参数的监测和干预,从而达到改善预后的目的。
文摘In this study, we consider the heat-induced withdrawal reflex caused by exposure to an electromagnetic beam. We propose a concise dose-response relation for predicting the occurrence of withdrawal reflex from a given spatial temperature profile. Our model is distilled from sub-step components in the ADT CHEETEH-E model developed at the Institute for Defense Analyses. Our model has only two parameters: the activation temperature of nociceptors and the critical threshold on the activated volume. When the spatial temperature profile is measurable, the two parameters can be determined from test data. We connect this dose-response relation to a temperature evolution model for electromagnetic heating. The resulting composite model governs the process from the electromagnetic beam deposited on the skin to the binary outcome of subject’s reflex response. We carry out non-dimensionalization in the time evolution model. The temperature solution of the non-dimensional system is the product of the applied power density and a parameter-free function. The effects of physical parameters are contained in non-dimensional time and depth. Scaling the physical temperature distribution into a parameter-free function greatly simplifies the analytical solution, and helps to pinpoint the effects of beam spot area and applied power density. With this formulation, we study the theoretical behaviors of the system, including the time of reflex, effect of heat conduction, biological latency in observed reflex, energy consumption by the time of reflex, and the strategy of selecting test conditions in experiments for the purpose of inferring model parameters from test data.
