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31.
This paper investigates the exponential synchronization of coupled memristor-based chaotic neural networks with both time-varying delays and general activation functions. And here, we adopt nonsmooth analysis and control theory to handle memristor-based chaotic neural networks with discontinuous right-hand side. In particular, several new criteria ensuring exponential synchronization of two memristor-based chaotic neural networks are obtained via periodically intermittent control. In addition, the new proposed results here are very easy to verify and also complement, extend the earlier publications. Numerical simulations on the chaotic systems are presented to illustrate the effectiveness of the theoretical results. 相似文献
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毛健 《中国小儿急救医学》2014,21(10):617-621
早产儿呼吸暂停(apnea of prematurity,AOP)定义一直是缺少充分的临床证据的,以呼吸停止时间≥20S,或〈20S伴有心动过缓、发绀为通常临床定义。目前还没有统一的AOP管理规范,但是反复发作的AOP,导致反复的间隙性缺氧(intermittent hypoxic episodes,IHE)是血氧波动的主要原因,同时,使早产儿发生严重早产儿视网膜病变和神经精神发育障碍的风险增加。当然,IHE的原因不仅局限于AOP,呼吸支持规程中,无论是持续气道正压通气,还是有创通气过程中都有发生IHE的可能。降低IHE是早产儿呼吸管理的核心内容之一,合理目标氧饱和度应是动态变化的,90%~95%的目标有助于减轻IHE和降低病死率,但有可能使早产儿视网膜病变增加。咖啡因是治疗AOP的首选药物,但是对混合型AOP廊注意呼吸支持。减少肺容积和气道阻力。 相似文献
34.
《Brain stimulation》2020,13(5):1211-1217
BackgroundAccelerated intermittent Theta Burst Stimulation (aiTBS) has been shown to be an effective antidepressant treatment. Although neurobiological changes shortly after this intervention have been reported, whether aiTBS results in structural brain changes must still be determined. Furthermore, it possible that rapid volumetric changes are driven by factors other than neurotrophic processes.ObjectivesWe examined whether possible grey matter volumetric (GMV) increases after aiTBS treatment could be driven by increased brain perfusion, measured by Arterial Spin Labeling (ASL).Methods46 treatment-resistant depressed patients were randomized to receive 20 sessions of active or sham iTBS applied to the left dorsolateral prefrontal cortex. All sessions were delivered over 4 days at 5 sessions per day (trial registration: http://clinicaltrials.gov/show/NCT01832805). Patients were scanned the day before starting stimulation and three days after aiTBS.ResultsThere was a significant cluster of increased left hippocampal GMV in the dentate gyrus related to HRSD changes after active aiTBS, but not after sham stimulation. These GMV increases became more pronounced when accounting for changes in cerebral perfusion.ConclusionsActive, but not sham, aiTBS, resulted in acute volumetric changes in parts of the left dentate gyrus, suggesting a connection with adult neurogenesis. Furthermore, taking cerebral perfusion measurements into account impacts on detection of the GMV changes. Whether these hippocampal volumetric changes produced by active aiTBS are necessary for long-term clinical improvement remains to be determined. 相似文献
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Prospective Population-Based Study of Intermittent and Continuous Convulsive Status Epilepticus in Richmond, Virginia 总被引:4,自引:4,他引:0
Elizabeth J. Waterhouse Linda K. Garnett Alan R. Towne Lawrence D. Morton Thomas Barnes Daijin Ko Robert J. DeLorenzo 《Epilepsia》1999,40(6):752-758
PURPOSE: Previous work suggested that there is a lower mortality for convulsive status epilepticus (SE) with intermittent seizures (intermittent SE) as opposed to SE with continuous seizure activity (continuous SE). A plausible hypothesis to explain this difference is that the shorter ictal time in intermittent SE is responsible for the lower mortality in this group. This study investigates the relative contributions of total ictal time and SE duration to the differing mortalities of intermittent and continuous SE. METHODS: Six hundred forty-five cases of prospectively identified convulsive SE were examined. Nonparametric statistical methods were used to compare continuous SE and intermittent SE variables. Multivariate logistic regression analyses were used to determine which factors were most highly associated with mortality. Intermittent SE cases were analyzed to evaluate the relative contributions of ictal time versus SE duration to mortality. RESULTS: Intermittent SE had a significantly lower mortality than continuous SE (19.6 vs. 31.4%; p < 0.001) in adults but not in children. Intermittent and continuous SE durations did not significantly differ in adult cases but did differ in pediatric cases. Ictal time was significantly shorter than SE duration for intermittent SE in both adults and children. After adjusting for age, etiology, and SE duration, SE type (continuous SE vs. intermittent SE) was shown to have an independent effect on mortality in adults. The relative risk of mortality for continuous SE was 1.79 times that of intermittent SE (p = 0.04). After controlling for SE duration, ictal time did not significantly affect mortality in adults. CONCLUSIONS: Intermittent and continuous convulsive SE were common in both pediatric and adult populations. Intermittent SE had a significantly lower mortality than did continuous SE. This difference in mortality was not completely explained by differences in SE duration, total ictal time, etiology, or age. Further research is needed to identify the factor(s) contributing to the significant difference in mortality between intermittent SE and continuous SE. 相似文献
37.
目的 观察间歇性高容量血液滤过(IHVHF)对严重感染和感染性休克患者28 d生存情况的影响.方法 采用回顾性队列研究,收集因急性肾衰竭或多器官功能衰竭(MOF)接受IHVHF的严重感染或感染性休克患者的基础资料、IHVHF治疗方式及治疗期间的相关信息,采用COX风险比例模型分析患者IHVHF治疗后28 d死亡的危险因素.结果 共44例患者纳入本研究,按照患者进行IHVHF的平均剂量分为高剂量组(≥70 ml· kg-1·h-1,17例)和低剂量组(<70 ml·kg-1·h-1,27例).高剂量组和低剂量组患者除体质指数(kg/m2)有明显差异(20.7±3.2比25.3±3.0,P<0.01)外,基础情况及IHVHF治疗方式均无明显差异.44例患者中28 d内死亡17例,患者实际28 d病死率明显低于预期病死率[38.6%比(61.8±21.9)%,P<0.01],且高剂量组28 d病死率显著低于低剂量组[11.8%(2/17)比55.6%(15/27),P=0.004].多因素COX风险比例模型分析发现,IHVHF前高序贯器官衰竭评分(SOFA)可增加28 d死亡风险[相对危险度(RR)=1.279,95%可信区间(95%CI)1.127 ~ 1.452,P<0.001],而高剂量IHVHF (RR=0.149,95%CI 0.032~0.694,P=0.015)及IHVHF总时间长(RR=0.981,95%CI0.966~0.997,P=0.016)可降低28 d死亡风险.结论 对于合并急性肾衰竭或MOF的严重感染和感染性休克患者,高剂量IHVHF(≥70 ml·kg-1·h-1)是减少患者28d死亡的保护性因素,延长IHVHF时间可以降低28 d病死率. 相似文献
38.
目的:探讨驻内蒙古某团患间歇性变应性鼻炎(allergic rhinitis,AR)官兵皮肤点刺试验(skin prick test,SPT)阳性界值对血清特异性IgE(specific IgE,sIgE)诊断价值的影响,并评估SPT与血清sIgE测定值的诊断一致性。方法对驻内蒙古某团66例间歇性AR临床症状和体征的官兵进行23种常见的吸入变应原的SPT,选择阳性变应原数量≥4个和SPT阳性结果等级高者31例进行sIgE检测,采用瑞典Pharmacia的UniCAP100系统检测其血清中艾蒿、苦蒿、三裂叶豚草、葎草、榆树、柳树、桦树和蒲公英的血清sIgE,以临床症状、体征和SPT阳性结果作为诊断AR的参考标准,评价SPT阳性界值“+”和“++”对UniCAP100系统检测血清sIgE诊断价值的影响。评价指标包括灵敏度、特异度、阳性预测值、阴性预测值、一致率,并评价两种检测方法的一致性。结果①蒿属花粉是该驻地官兵间歇性AR的最主要变应原,其SPT阳性率在60%以上,其次依次是向日葵、葎草、豚草、白桦、榆树、柳树,SPT阳性率均在30%以上。②以SPT“+”为阳性界值时,血清sIgE的灵敏度为0.500(葎草)~0.982(蒿属),特异度为0.500(豚草、榆树、桦树)~1.000(蒿属),一致率为0.581(葎草)~0.984(蒿属);以SPT“++”为阳性界值时,血清sIgE的灵敏度为0.524(葎草)~0.982(蒿属),特异度为0.462(豚草)~1.000(蒿属),一致率为0.581(豚草、柳树)~0.984(蒿属),诊断指标无明显变化。③两种检测方法诊断一致性,经Kappa检验显示,蒿属、豚草、葎草、榆树、柳树、桦树Kappa值分别是0.900(P=0.000)、0.131(P=0.447)、0.214(P=0.155)、0.377(P=0.034)、0.209(P=0.242)、0.158(P=0.373)。结论以蒿属花粉为代表的夏秋季杂草花粉和部分春季树花粉是该驻地官兵间歇性AR的主要变应原;SPT阳性界值“+”和“++”对UniCAP100系统检测血清sIgE诊断价值的影响不大;SPT和血清sIgE检测在蒿属花粉和榆树花粉致敏的诊断中具有较好的一致性。 相似文献
39.
《Annales de cardiologie et d'angeiologie》2018,67(1):48-53
IntroductionSeveral cases of sudden deaths are observed among students practicing sport and physical activity (SPA). Just few studies have been carried out on the variation of the QT (interval) and risk of sudden death during sporting exercises.AimTo determine the effect of variable intermittent stress intensity on the variation of QT and the risk of sudden cardiac death.Patients and methodsForm 4, lower sixth and upper sixth students were recruited from a high school in Douala (Cameroon). Each subject was tested; starting with a 2-km walk followed by a sprint race or an endurance race, protocol I (P1) or the reverse; protocol II (P2). Two electrocardiograms were recorded; prior to the beginning of the SPA and 5 minutes after the last race. QT was corrected using four formulas.ResultsForty-one subjects (21 women and 20 men), mean age 18 ± 2 years were recruited. At the end of the exercise, corrected QT increased with Bazzet's formula and decreased with Frahmingam's formula. The difference was not significant with Fridericia and Hodges formulas. The frequency of long QT was higher at the end of the exercise with Bazzet's formula (12.2% vs. 24.4%, P = 0.009) while the difference was not significant for the other formulas.ConclusionThe risk of sudden cardiac death increases significantly after SPA. More studies on large samples are needed. 相似文献
40.
J. L. Carpintero A. Rodriguez Diez M. J. Ruiz Elvira J. A. Benitez A. Perez Rielo 《Intensive care medicine》1980,6(4):217-221
We have treated 30 patients with flail chest, with priority given to associated factors (pain, secretions retention, hemo-/pneumothorax and underlying pulmonary contusion). When this treatment was insufficient IMV+PEEP was instituted; in this group there was a 58.8% incidence of pneumonia, 47.5% of sepsis and 11.7 days average stay in the ICU. These were significantly different when compared to the patients controlled without mechanical ventilatory support (7.7% pneumonia, 0% sepsis, 3.2 days).Surgical fixation was limited to 4 patients who presented with multiple and greatly displaced rib fractures, which made fixation by mechanical ventilation unpredictable. 相似文献