基于OA及免费全文链接的期刊影响力指数优势

【目的】 为开放获取政策的制定提供理论参考,给学术搜索引擎免费全文链接的建设提供依据。【方法】 对图书馆、情报与文献学领域的26种中文社会科学引文索引来源期刊的开放获取状况与免费全文链接情况进行调查。根据期刊的开放获取状态和免费全文链接获得程度将期刊分为4类,分别在不同的时间视窗下比较4类期刊的各项评价指标的变化趋势,并进行相关性分析。【结果】 所选的26种期刊的开放获取程度为61.5%,这些期刊在百度学术中平均每篇论文拥有2.17个免费全文链接。开放获取和有高免费全文链接获得程度的期刊在不同时间视窗影响力指数下的表现都较占优势。【结论】 期刊开放获取和有较多的免费全文链接有助于期刊的被引用和影响力的提升。     

Effects of the Anaesthetic-ECT time interval and ventilation rate on seizure quality in electroconvulsive therapy: A prospective randomised trial

BackgroundThe anaesthetic approach adopted in ECT practice has the potential to influence patient outcomes. However, the impact of the time interval between anaesthetic induction and ECT stimulus administration has not been studied prospectively to date. This variable may represent an indirect measure of anaesthetic concentration at the time of stimulation, and therefore may influence the quality of seizures induced.ObjectiveTo examine the impact of the anaesthetic to ECT stimulus time interval, and ventilation rate pre-treatment, on ictal seizure quality.MethodsIn a prospective, crossover trial, 54 depressed participants were randomised to variations in anaesthetic technique at four sequential ECT treatment sessions, in a 2 x 2 design: randomisation to a short or long anaesthetic-ECT time interval, and randomisation to normal ventilation or hyperventilation during anaesthetic induction with thiopentone. Ictal EEG data were collected at each study session and assessed by a blinded rater for ictal quality (seizure amplitude, regularity, post-ictal suppression and general seizure quality), using a quantitative-qualitative structured rating scale. Linear mixed effects models were used to analyse the effect of the anaesthetic-ECT time interval, and that of ventilation rate, on seizure quality indices.ResultsThe anaesthetic-ECT time interval had a significant impact on ictal EEG quality indices (p < 0.01), with longer time intervals producing higher quality seizures. Ventilation rate did not significantly influence quality measures.ConclusionThe time between anaesthetic induction and ECT stimulus administration has a significant impact on ictal EEG seizure quality. Conversely, manipulations of ventilation rate did not significantly affect seizure quality. These results suggest the anaesthetic-ECT time interval should be routinely monitored clinically and potentially optimised for maximising seizure quality with ECT.     

Two types of ictal phase-amplitude couplings in epilepsy patients revealed by spectral harmonicity of intracerebral EEG recordings

ObjectiveSpectral harmonicity of the ictal activity was analyzed regarding two clinically relevant aspects, (1) as a confounding factor producing ‘spurious’ phase-amplitude couplings (PAC) which may lead to wrong conclusions about the underlying ictal mechanisms, and (2) its role in how good PAC is in correspondence to the seizure onset zone (SOZ) classification performed by the epileptologists.MethodsPAC patterns observed in intracerebral electroencephalography (iEEG) recordings were retrospectively studied during seizures of seven patients with pharmacoresistant focal epilepsy. The time locked index (TLI) measure was introduced to quantify the degree of harmonicity between frequency bands associated to the emergence of PAC during epileptic seizures.Results(1) Harmonic and non harmonic PAC patterns coexist during the seizure dynamics in iEEG recordings with macroelectrodes. (2) Harmonic PAC patterns are an emergent property of the periodic non sinusoidal waveform constituting the epileptiform activity. (3) The TLI metric allows to distinguish the non harmonic PAC pattern, which has been previously associated with the ictal core through the paroxysmal depolarizing shifts mechanism of seizure propagation.ConclusionsOur results suggest that the spectral harmonicity of the ictal activity plays a relevant role in the visual analysis of the iEEG recordings performed by the epileptologists to define the SOZ, and that it should be considered for the proper interpretation of ictal mechanisms.SignificanceThe proposed harmonicity analysis can be used to improve the delineation of the SOZ by reliably identifying non harmonic PAC patterns emerging from fully recruited cortical and subcortical areas.     

Association of retrospective time estimation and severity of cognitive impairment

Introduction. Time perception has an important role in everyday life, but is not commonly measured in clinical routine assessment of suspected cognitive impairment, given the complexity of available assessment methods. Furthermore, evidence on the pattern of retrospective time perception in neurodegenerative diseases is contradictory. Method. We asked 321 patients referred to neuropsychological assessment to retrospectively estimate the duration of the neuropsychological assessment session. We calculated the session actual duration, ratio, and accuracy of response. Patients were grouped into three categories: subjective cognitive impairment, mild cognitive impairment, and mild to moderate dementia. Results. We found an overall tendency for underestimation of time, but no significant differences between groups regarding time estimation. There were significant, but weak, associations between time estimation and severity of cognitive impairment in several domains, with slightly different patterns across groups. Conclusions. Regardless of etiology, the majority of patients underestimated time, which was weakly associated with the severity of cognitive impairment. Global retrospective estimation may be clinically informative, particularly in a minority of extreme cases.     

心房颤动对不同时间窗内急性缺血性脑卒中患者静脉溶栓疗效的影响

目的探讨急性缺血性脑卒中合并心房颤动患者不同时间窗内静脉溶栓的疗效差异。方法选取急性缺血性脑卒中行静脉溶栓治疗患者172例,根据发病-溶栓时间窗差异分为3组,时间窗分别为≤3.0 h(观察A组)、>3.0~4.5 h(观察B组)、>4.5 h(观察C组),对其中合并心房颤动者溶栓疗效进行评估分析。结果3组患者溶栓24 h后出血转化结果、溶栓3个月时神经功能结局良好率、病死率均无明显差异(P>0.05);溶栓时间窗>3 h者,心房颤动可显著增加患者发生PH型、HI型出血转化发生率,差异有统计学意义(P<0.05);单因素分析显示,合并心房颤动可造成溶栓时间窗≤4.5 h患者神经功能结局不良发生率增加,差异有统计学意义(P<0.05)。多因素分析显示,合并心房颤动与不同时间窗急性缺血性脑卒中患者静脉溶栓治疗后神经功能结局不良发生情况无明显相关性(P>0.05)。结论溶栓时间窗仍是影响急性缺血性脑卒中患者静脉溶栓疗效的重要因素,对于溶栓时间窗≤3.0 h者,合并心房颤动不会对溶栓疗效造成影响;对于发病-溶栓时间>3 h者,心房颤动可能造成患者溶栓后出血风险增加。