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We investigated the influence of processing steps in the estimation of multivariate directed functional connectivity during seizures recorded with intracranial EEG (iEEG) on seizure-onset zone (SOZ) localization. We studied the effect of (i) the number of nodes, (ii) time-series normalization, (iii) the choice of multivariate time-varying connectivity measure: Adaptive Directed Transfer Function (ADTF) or Adaptive Partial Directed Coherence (APDC) and (iv) graph theory measure: outdegree or shortest path length. First, simulations were performed to quantify the influence of the various processing steps on the accuracy to localize the SOZ. Afterwards, the SOZ was estimated from a 113-electrodes iEEG seizure recording and compared with the resection that rendered the patient seizure-free. The simulations revealed that ADTF is preferred over APDC to localize the SOZ from ictal iEEG recordings. Normalizing the time series before analysis resulted in an increase of 25–35% of correctly localized SOZ, while adding more nodes to the connectivity analysis led to a moderate decrease of 10%, when comparing 128 with 32 input nodes. The real-seizure connectivity estimates localized the SOZ inside the resection area using the ADTF coupled to outdegree or shortest path length. Our study showed that normalizing the time-series is an important pre-processing step, while adding nodes to the analysis did only marginally affect the SOZ localization. The study shows that directed multivariate Granger-based connectivity analysis is feasible with many input nodes (>?100) and that normalization of the time-series before connectivity analysis is preferred.  相似文献   
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目的探讨外用糖皮质激素长疗程间歇疗法治疗神经性皮炎的疗效、安全性及复发情况,为指导临床用药提供依据。方法采用随机对照开放试验,选取门诊神经性皮炎患者,外用复方氟米松软膏常规疗法短期治疗。将已短期治愈入选的120例患者随机分为2组,试验组外用复方氟米松软膏进行长疗程间歇治疗,2次/d;对照组外用尿素霜(成分:尿素,羊毛脂,白蜡,凡士林)进行治疗,2次/d。2组每周用药2 d,每次间隔3 d用药,疗程8周。在长疗程治疗4周、8周及停药12周时各随访1次,分别比较2组患者的复发率。结果长疗程治疗8周及停药12周时,试验组SCORAD评分均显著低于对照组(P均〈0.05)。长疗程治疗4周、8周及停药12周时,试验组复发率均显著低于对照组(P均〈0.05)。治疗期间不良反应发生率1.67%,无严重不良事件。结论外用糖皮质激素长疗程间歇治疗神经性皮炎,效果好,不良反应少,有预防症状加重、延缓复发的作用。  相似文献   
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This study aimed to assess the longitudinal validity of the oral impacts on daily performance (OIDP) and to identify psychosocial determinants, in terms of self‐efficacy and depressive symptoms, of the OIDP across time. Following conceptual frameworks of oral health, it was hypothesized that sociodemographic, clinical, and psychosocial factors predict oral impacts across time at both population‐ averaged and person‐specific levels. Whether the effects of sociodemographic and clinical factors were accounted for, totally or in part, by psychosocial factors were also investigated. Self administered questionnaires and oral clinical examinations at baseline (2009) and follow‐up (2011) were completed by 1,714 and 727 secondary school students, respectively. Generalized equalized equations and a random intercept model were used to account for the dependency in repeated observations. Mean OIDP change scores were negative (worsened) among those who reported worsened self‐reported oral health. Psychosocial, clinical, and sociodemographic factors were independently associated with oral impacts at the population‐averaged and person‐specific levels. Mediation of sociodemographic and clinical variables according to psychosocial variables was not observed. Satisfactory longitudinal evaluative properties of the OIDP, and independent effects of psychosocial factors on oral impacts across time, were confirmed among secondary school students in Tanzania.  相似文献   
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主动固定电极在右室流出道间隔部起搏中的应用研究   总被引:14,自引:1,他引:14  
目的评价主动固定电极在右室流出道间隔部起搏应用中的可行性和稳定性。方法160例起搏适应证患者随机分为两组,每组80例,一组采用主动固定电极行右室流出道间隔部起搏(简称主动固定电极组),另一组应用被动固定电极行右室心尖起搏(简称被动固定电极组),观察电极置入时间和心电图QRS波宽度,电极置入后随访观察起搏阈值、感知、阻抗,电极脱位及相关并发症。结果主动固定电极组的置入时间和X线曝光时间均长于被动固定电极(26.34±6.54minvs20.86±4.32min,16.78±5.38minvs8.67±4.52min;P均<0.01)。主动固定电极组电极置入15min时较置入即刻的起搏阈值明显下降(0.76±0.21mVvs1.12±0.25mV,P<0.01)。主动固定电极组起搏的QRS波时限较被动固定电极组短(0.14±0.04msvs0.16±0.03ms,P<0.01)。术后随访1,3,6个月,两组的起搏阈值、感知、阻抗均无差异,未见电极脱位等并发症。结论主动固定电极在右室流出道间隔部起搏中的应用是可行和稳定的。  相似文献   
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Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
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Li  Jia  Xue  Zhixin  Wu  Zhenbiao  Bi  Liqi  Liu  Huaxiang  Wu  Lijun  Liu  Shengyun  Huang  Xiangyang  Wang  Yong  Zhang  Yan  Qi  Wufang  He  Lan  Dai  Lie  Sun  Lingyun  Li  Xiaomei  Shuai  Zongwen  Zhao  Yi  Wang  Yanyan  Xu  Jian  Zhang  Hao  Yu  Hao  Chen  Xiaoxiang  Bao  Chunde 《Clinical rheumatology》2022,41(10):3005-3016
Clinical Rheumatology - To assess the clinical equivalence of TQ-Z2301, a biosimilar of adalimumab, to the reference adalimumab in the treatment of Chinese patients with active ankylosing...  相似文献   
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