原发性肝癌实时超声造影时间窗的临床研究

目的 探讨原发性肝癌（HCC）超声造影（CEUS）时间窗及影响因素。 方法 经左肘静脉团注造影剂SonoVue 2．4ml后，分别以肝动脉、门脉主干或二、三级分支显影作为动脉相（AP）、门脉相（PVP）的开始，肝实质回声增强达峰值视为实质相（PP）的开始，2min后为延迟相（DP）。 结果 肝癌CEUS各时相出现的早晚及持续时间的长短，主要与HCC血供性质有关，血管间短路亦有一定影响。HCC血供分2种形式，第一型最多见，呈动态变化过程。初期以门静脉供血为主，动脉呈低血供，而后二者均减少，随着瘤体的增大，动脉供血逐渐增加呈等血供，直至高血供。第二型则主要以门静脉供血为主。以动脉供血为主的HCC，AP快速强化，PVP消退，该表现见于大多数HCC。以门静脉供血为主者，AP、PVP均强化，至PP方消退，该现象见于小肝癌（sHCC）。动门瘘时可使AP缩短，PVP提前显影。 结论 以相关血管显影作为时相的起始及时段，能较全面反映肿瘤特征，有助于定性诊断。主供血管的性质将影响时相的起始及长短。     

Optimal time-window duration for computing time/frequency representations of normal phonocardiograms in dogs

The optimal duration of the time-window used to compute the time-frequency representation (spectrogram) of the phonocardiogram was studied in four dogs by using intracardiac and thoracic measurements of the PCG. The power and cross-spectrograms of the intracardiac and thoracic PCGs were computed using a fast Fourier transform algorithm and a sine-cosine window with 10 per cent decaying functions. A coherence spectrogram was also computed for each dog to study the linear relationship between the two signals and determine the optimal time-window duration. Results show that the optimal range of the time-window duration is between 16 and 32 ms. A time-window shorter than 16ms spreads out low-frequency components into the higher frequencies and generates a spectrographic representation with poor frequency resolution (≥62·5 Hz). A window larger than 32 ms increases the frequency resolution but smears the spectrographic representation of the signal in the time domain and thus cannot correctly reflect the time-varying properties of the signal. In both cases, the amplitude of the coherence function computed between the left ventricular and the thoracic phonocardiograms is overestimated.     

水面舰艇长期远航影响舰员生理和心理健康状况的时间窗比较

目的比较研究水面舰艇长期远航影响舰员生理和心理健康状况的时间窗差异,为制定合理的卫勤保健提供依据。方法随舰统计某水面舰艇258名男性舰员远航20周期间的患病情况（两周患病率）;并于出航前第7天和远航第28天、77天、142天采用症状自评量表（Symptom Checklist90,SCL-90）对舰员的心理健康状况进行抽样调查分析。结果出航后舰员的两周患病率急剧升高、并迅速达到高峰,以后逐渐下降。远航8周后的两周患病率趋于稳定和常态化,与出航前比较未见明显差异（P〉0.05）;远航第28天舰员SCL-90总均分和各项因子分值与出航前比较无明显差异（P〉0.05）,但远航第77天舰员的SCL-90总均分和躯体化、敌对性、偏执、其他因子分值明显高于出航前水平（P〈0.05）,其中敌对性因子分值还明显高于军人常模值（P〈0.05）。远航第142天的心理测评中,除其他因子项分值仍显著高于出航前水平（P〈0.05）外,舰员的SCL-90总均分和各因子分值均基本回落至出航前水平（P〉0.05）。结论水面舰艇长期远航影响舰员生理和心理健康状况的时间窗存在明显差异,前者位于远航初期,而后者在航行中期。     

Sensitive and critical periods during neurotypical and aberrant neurodevelopment: A framework for neurodevelopmental disorders

During sensitive and critical periods, the brain undergoes significant plasticity from the level of individual synapses and neuronal networks up to the level of behaviour. Both sensitive and critical periods during neurotypical development of the young animal provide a framework to the early temporally-regulated modifications that occur in the nervous system.In neurodevelopmental disorders (NDD), notably autistic syndromes and intellectual disability, children exhibit developmental delays in motor, social and sensory processes and often miss key developmental milestones. In corresponding genetic NDD mouse models, recent data reveal temporally-regulated and in some cases, transient impairments in many neuronal and behavioural phenotypes during development. However, the mechanisms underlying these impairments in NDDs and their potential links with neurobiological mechanisms governing neurotypical development are not fully investigated. This article highlights the potential for the use of known critical and sensitive periods during vertebrate development to investigate and advance our understanding of the neural bases underlying impairments in these developmental disorders of the nervous system.     

丹参对不同时间窗急性脑梗死中CGRP、ET含量的影响

目的研究丹参对两种时间窗的脑梗死急性期（ACI）患者的作用机制与其降钙素基因相关肽（CGRP）、血管内皮素（ET）血清含量变化的相关性寻找丹参的最佳治疗时间窗。方法依据其入院时的发病时间,40例病例均衡地分为两大组,其中发病24h内入院者为早期组,发病24h～7d入院者为晚期组,每大组又分为观察组和治疗组两小组,每组患者均于入院前、疗程完成时测量CGRP、ET含量。结果疗程完成时测量早期治疗组脑梗死患者CGRP含量高于早期对照组（P〈0.05）,但是ET含量低于早期对照组（P〈0.05）;早期治疗组ET含量也明显低于晚期治疗组（P〈0.05）。结论研究提示丹参治疗脑卒中有时间依赖性,它能影响ET、CGRP含量变化,在早期时间窗丹参能通过抑制ET和升高CGRP起到保护作用。故发病24h入院为其最佳治疗时间窗。     

r-tPA动脉溶栓治疗超时间窗急性脑梗死

目的 研究CT灌注指导下r-tPA动脉溶栓治疗6～9h时间窗内急性脑梗死的疗效与安全性.方法 前瞻对照研究2008年1月至2010年12月厦门大学附属第一医院神经内科收治的脑梗死患者,将63例发病6～9h内CT灌注成像提示存在缺血半暗带的急性脑梗死患者随机(随机数字法)分为A、B两组,A组给予r-tPA动脉接触溶栓,B组给予常规抗血小板等治疗.各组患者在治疗前、治疗后24 h和7d行NIHSS评分,90 d行mRS及BI评分以评定临床预后;A组患者术前、术后行脑血管DSA检查,判定闭塞血管再通情况;两组患者24 h内均复查颅脑CT,观察是否合并脑出血.结果 A组30例,B组33例;治疗前后比较,NIHSS评分差异24 h时A组差异有统计学意义(P＜0.01),B组差异无统计学意义(P＞0.05),7d时两组均有统计学意义(P＜0.01),组间比较显示A组较B组在治疗后24 h、7d时NIHSS评分下降更显著(P＜0.01);治疗后90 d良好预后者A组明显多于B组(P＜0.05);A组溶栓治疗后成功再通20例(66.67％),24h内有2例并发脑出血,与B组比较差异无统计学意义(P＞0.05).结论 CT灌注指导下r-tPA动脉溶栓是治疗6～9h时间窗内急性脑梗死的一种安全有效方法.     

THE VERY ACUTE STROKE TREATMENT: FIBRINOLYSIS AND AFTER

Thrombolytic therapy with rt-PA given within 3?h after stroke onset to patients with ischemic stroke significantly improves outcome after stroke. There are some evidences that thrombolysis may also work up to 6?h after stroke onset in carefully identified patients, but the three most important trials, which used 0–6?h time-windows, combined with CT-scans to define the ischemic areas, failed individually to produce statistical benefits for the rt-PA-treated patients. In order to enlarge the time-window there is a need for additional information about the functionality of the affected brain area. There is a growing interest in the use of Diffusion Weighted (magnetic resonance) imaging (DWI) and Perfusion Weighted (magnetic resonance) imaging (PWI) in the assessment of patients with acute ischemic stroke. These magnetic resonance techniques are powerful methods for identifying the extent and location of early cerebral ischemia.     

Delayed changes of sleep duration after rewarded olfactory discrimination learning in the rat

The aim of this experiment was to determine if a task of associative olfactory learning, based on the ethological repertory of rats and learnt rapidly in 5 successive trials, could modify slow wave sleep (SWS) and/or paradoxical sleep (PS) duration after learning and/or after a retrieval–reactivation test 24 h later. Somnopolygraphic recordings were performed for 20 h per day on trained and control (submitted to a pseudo-learning test) rats. SWS and PS durations were analyzed per 20 h and per 4 h time-periods. Compared to control rats, after learning, trained rats showed a significant increase in SWS duration counterbalanced by a significant decrease in wake duration focused on the 5–8 h post-training time-window and a significant decrease in PS duration during the 17–20 h post-training time-window. After the retrieval–reactivation test trained rats only showed a decreased PS duration compared to control rats submitted to a pseudo-retrieval test. Thus, a rather simple learning task succeeded in eliciting an increase in SWS duration in a limited time-window. As the learning task used can be compared to human associate-paired learning, this result sustains the hypothesis of a link between declarative memory and SWS. In control rats, changes in PS duration might be linked to odorized-environment exposure.     

Neuroprotective action of tacrolimus (FK506) in focal and global cerebral ischemia in rodents: dose dependency,therapeutic time window and long-term efficacy

Tacrolimus (FK506), a potent immunosuppressive drug, is effective in attenuating brain infarction after cerebral ischemia. However, there has been no report characterizing the neuroprotective action and therapeutic time window of tacrolimus systematically using different types of stroke models and extended observation periods. Therefore, we evaluated the neuroprotective effect of tacrolimus in three different animal models of cerebral ischemia: transient and permanent focal ischemia in rats and transient global ischemia in gerbils. Tacrolimus at doses higher than 0.1 mg/kg (i.v.) produced a statistically significant reduction in ischemic brain damage following permanent and transient focal ischemia in rats when administered immediately after the onset of ischemia. Tacrolimus (1 mg/kg, i.v.) demonstrated similar neuroprotective activity even after delayed administration (2 h after permanent or 1 h after transient focal ischemia). The neuroprotective effect of tacrolimus was still present 2 weeks after transient focal ischemia and 1 week after permanent focal ischemia. After transient global ischemia in gerbils, tacrolimus (1 mg/kg, i.v.) given immediately after reperfusion also produced long-lasting neuroprotective effects with a protective time-window of 1-2 h. Taken together, the results clearly indicate that tacrolimus exerts potent, long-term neuroprotective effects with a favorable therapeutic time-window, regardless of the model of cerebral ischemia. These results strengthen the notion that tacrolimus might be of clinical value for the treatment of acute stroke.