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31.
Tracheal and lung sounds measurements for clinical applications depends on their intrasubject repeatability. Our objectives were to characterize tracheal and lung sounds and to investigate the temporal variability in normal adults. Tracheal sounds were studied in 7 subjects and lung sounds in 10 adults. Acoustic measurements were done in five occasions over a month for tracheal sounds and on seven occasions over a year for lung sounds. Sounds were recorded using contact sensors on the suprasternal notch and on the posterior right lower lobe. Subjects breathed through a pneumotachograph at flows of 0.9–1.1 l/s. Signals were low-pass filtered, amplified and Fourier analysis was applied to sounds within a target flow range. We measured the frequencies below which 25% (F25), 50% (F median), 75% (F75) and 99% (SEF99) of the spectral power between 100 and 2000 Hz. There were no differences between the measurements obtained at different days comparing each subject (P=ns, ANOVA). Our results show that the spectral pattern of tracheal and lung sounds are stable with low intrasubject variability. 相似文献
32.
Atrial fibrillation signal organization predicts sinus rhythm maintenance in patients undergoing cardioversion of atrial fibrillation. 总被引:1,自引:0,他引:1
Fredrik Holmqvist Martin Stridh Johan E P Waktare Anders Roijer Leif S?rnmo Pyotr G Platonov Carl J Meurling 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(8):559-565
AIMS: Electrical remodelling is believed to influence the outcome following cardioversion of patients with persistent atrial fibrillation (AF). However, the results in clinical studies are conflicting. We assessed the hypothesis that non-invasively obtained atrial fibrillatory organization can be used as a predictor of sinus rhythm (SR) maintenance. METHODS AND RESULTS: Fifty-four patients (37 men, age 67+/-11) with persistent AF (median duration 3 months, 1 day to 18 months), without anti-arrhythmic drug treatment, referred for cardioversion were studied. Assessment of the atrial harmonic decay was made by time-frequency analysis of the ECG. At 1-month follow-up, 30 patients had relapsed into AF. The mean harmonic decay at inclusion of those relapsing into AF was 1.5+/-0.3 compared with 1.1+/-0.3 among those maintaining SR (P=0.0004). Using a cut-off value of harmonic decay 相似文献
33.
ObjectiveWe discuss how to handle failure of first-pass non-invasive prenatal screening (NIPS) and investigate the pregnancy outcomes after second-pass failure.MethodsA total of 35,187 pregnant women underwent NIPS in a single center. Those who failed first-pass NIPS were re-tested after a repeat blood draw. Those who failed again were offered genetic counseling. We recorded antenatal data and pregnancy outcomes.ResultsA total of 273 (0.78%) women failed the first test. On re-testing, 220 (80.59%) yielded reliable results and 53 failed the test again. Women with higher total cell-free DNA (cfDNA) levels evidenced a lower NIPS success rate (40%) and a higher incidence of adverse pregnancy outcomes.ConclusionsMost women who failed first-pass NIPS yielded reliable results on repeat testing, especially those with lower fetal fraction. Higher concentrations of cfDNA in maternal plasma were associated with poorer pregnancy outcomes. Such women require special attention, thus early medical intervention, to avoid an adverse prognosis. 相似文献
34.
《Gait & posture》2021
BackgroundDespite advances in pharmacological treatments and surgical processes, the problem of impaired dual-tasking persists in people with Parkinson’s disease (PD). Recently, transcranial direct current stimulation (tDCS) applied to the dorsolateral prefrontal cortex (DLPFC) has shown the potential to improve dual-task walking.Research QuestionCan combining left DLPFC stimulation using tDCS with dual-task performance reduce the cost of dual-tasking in individuals with PD?MethodsWe conducted a sham-controlled, cross-over, and double-blind study to investigate the effect of combining tDCS with the dual-task walk and its sustained effects among people with PD. Twenty participants with PD completed two sessions (anodal or sham tDCS) with at least a 1-week gap. Stimulation involved transferring 2 mA current through the left DLPFC for 30 min. Single- and dual-task gait was assessed before, during, immediately after, 15, and 30 min after stimulation ceased. Phoneme verbal fluency task was given as the cognitive distractor during dual task.Results and ConclusionThe results of this study show that in the dual-task condition, participants walked faster at fifteen minutes (p = 0.017) and thirty minutes (p < 0.01) after anodal tDCS ceased compared to sham. Similarly, participants generated a higher number of words per minute at fifteen minutes (p = 0.017), and thirty minutes (p < 0.01) after anodal tDCS ceased compared to sham. Furthermore, the dual-task cost (DTC) associated with gait speed was significantly lower (p = 0.022) at fifteen minutes after anodal tDCS compared to sham tDCS. However, no significant effect of tDCS was observed on gait and cognitive performance under the single-task condition. In conclusion, left DLPFC stimulation can improve dual-tasking in participants with PD and the peaking of the tDCS effect was observed at fifteen minutes after stimulation ceased. 相似文献
35.
《Clinical neurophysiology》2021,132(2):568-580
ObjectiveFast Oscillations (FO) >40 Hz are a promising biomarker of the epileptogenic zone (EZ). Evidence using scalp electroencephalography (EEG) remains scarce. We assessed if electrical source imaging of FO using 256-channel high-density EEG (HD-EEG) is useful for EZ identification.MethodsWe analyzed HD-EEG recordings of 10 focal drug-resistant epilepsy patients with seizure-free postsurgical outcome. We marked FO candidate events at the time of epileptic spikes and verified them by screening for an isolated peak in the time-frequency plot. We performed electrical source imaging of spikes and FO within the Maximum Entropy of the Mean framework. Source localization maps were validated against the surgical cavity.ResultsWe identified FO in five out of 10 patients who had a superficial or intermediate deep generator. The maximum of the FO maps was localized inside the cavity in all patients (100%). Analysis with a reduced electrode coverage using the 10–10 and 10–20 system showed a decreased localization accuracy of 60% and 40% respectively.ConclusionsFO recorded with HD-EEG localize the EZ. HD-EEG is better suited to detect and localize FO than conventional EEG approaches.SignificanceThis study acts as proof-of-concept that FO localization using 256-channel HD-EEG is a viable marker of the EZ. 相似文献
36.
目的探究基于孕妇外周血胎儿游离DNA的无创产前基因检测(NIPT)和拓展性无创产前基因检测(NIPT-plus)在体外受精-胚胎移植(IVF)胎儿染色体异常筛查中的应用价值。方法收集2017年5月—2019年10月在复旦大学附属妇产科医院接受NIPT及NIPT-plus的孕妇,根据其受孕方式分为通过IVF方式受孕(IVF组)和自然受孕(对照组)。对所有研究对象NIPT、NIPT-plus及产前诊断检测结果进行回顾性分析,评价NIPT、NIPT-plus在IVF胎儿染色体异常,包括染色体非整倍体及拷贝数变异(CNV)筛查中的应用价值。结果IVF组孕妇1312例,年龄(32.83±4.02)岁,进行NIPT及NIPT-plus时平均孕周(15.59±2.16)周,其中单胎妊娠925例,双胎妊娠387例;对照组23031例,年龄(30.62±4.77)岁,进行NIPT及NIPT-plus时平均孕周(16.44±2.73)周,其中单胎妊娠22444例,双胎妊娠587例。IVF组NIPT提示21三体(T21)4例(3.05‰),阳性预测值(PPV)为100%;13三体(T13)3例(2.29‰);性染色体异常17例(12.96‰),PPV为55.56%;CNV 3例(2.29‰);其他染色体异常6例(4.57‰),PPV为33.33%。结论NIPT及NIPT-plus在IVF胎儿染色体非整倍体筛查中具有重要价值,常染色体及性染色体三体高风险结果具有较高参考价值;应用于IVF胎儿染色体单体及CNV筛查高风险结果具有一定的预警作用。 相似文献
37.
《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2021,25(4):421-427
BackgroundThe use of continuous positive airway pressure (CPAP) applied early after birth improves several outcomes when compared with intubation and invasive mechanical ventilation. “Early CPAP” protocols vary in relation to the pressure level, type of interface used, and studied sample.ObjectiveThis study compared intubation rate, exogenous surfactant use, and hospitalization length (among other variables) prior to and after adopting an “early CPAP” protocol in preterm infants with gestational age between 28 and 32 weeks, using intermediate pressures and short binasal prongs.MethodsThis was a retrospective study conducted in a public university hospital in Brazil. All preterm infants with gestational age between 28 and 32 weeks were included in the study. The newborns born between January 2011 and December 2012, prior to the protocol being implemented, were considered the historical control group, and those born after implementation, between February 2013 and August 2014 were considered the intervention group.ResultsThe participants in both groups had similar baseline characteristics (p > 0.05). There were significant reductions in intubation rate (89% versus 73%, p = 0.02), exogenous surfactant use (86% versus 67%, p = 0.02), and median (Q1 - Q3) days of invasive mechanical ventilation [4 (2 - 14) versus 1 (0.15–9), p = 0.01] and length of hospital stay in days [56 (42–77) versus 42 (35–71), p = 0.02].ConclusionsThe findings demonstrate positive outcomes of the early CPAP protocol. This protocol used simple and affordable equipment available in the hospital which could easily be reproduced in other centers, generating better outcomes for preterm infants and reducing hospital expenses. 相似文献
38.
Gabriel Tortella Roberta Casati Luana V M Aparicio Antonio Mantovani Natasha Sen?o Giordano D’Urso Jerome Brunelin Fabiana Guarienti Priscila Mara Lorencini Selingardi Débora Muszkat Bernardo de Sampaio Pereira Junior Leandro Valiengo Adriano H Moffa Marcel Simis Lucas Borrione André R Brunoni 《World Journal of Psychiatry》2015,5(1):88-102
The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry. 相似文献
39.
Saumya Jayakumar Michael S. Middleton Eric J. Lawitz Parvez S. Mantry Stephen H. Caldwell Hays Arnold Anna Mae Diehl Reem Ghalib Magdy Elkhashab Manal F. Abdelmalek Kris V. Kowdley C. Stephen Djedjos Ren Xu Ling Han G. Mani Subramanian Robert P. Myers Zachary D. Goodman Nezam H. Afdhal Rohit Loomba 《Journal of hepatology》2019,70(1):133-141
40.
《The Brazilian journal of infectious diseases》2020,24(1):51-57
IntroductionVaccines are well-established public health interventions with major impact on the prevalence of infectious diseases, but outbreaks are occurring frequently due to primary and secondary failures, despite high coverage. Surveillance of efficacy and duration of induced immunity is a difficult task as it requires invasive blood sampling in children and teenagers. Saliva can be an acceptable alternative source of IgG to assess vaccine efficacy and toxoplasmosis incidence. We investigated IgG response for measles, mumps, rubella, and T. gondii in saliva samples of vaccinated young people.MethodsSaliva was collected from 249 public schools students from São Paulo, Brazil, aged 7 to 13 years old, during an interactive exhibition on hygiene. We used S. aureus protein A solid phase capture assay for IgG reactive to biotinylated purified proteins. Paired saliva and serum (47) were tested from young adults with serum evidence of T. gondii infection and from negative children less than 12 month old for standardization. Reproducibility was greater than 98% and sensitivity and specificity of the saliva assays were greater than 95%, as well as the concordance of paired saliva and serum samples.ResultsSaliva from high school students showed a prevalence of 8.5% (95% CI: 5.0–11.9%) for anti T. gondii IgG; 96.8% (94.6–99%) of anti-measles IgG; 59.1% (53–65%) of anti-rubella IgG, and 57.5% (51.3–63.6%) of anti-mumps IgG.DiscussionThe prevalence of antibodies against mumps and rubella after 6–8 years of vaccination was lower than against measles among students. The findings of this study demonstrate the feasibility of saliva sampling for follow-up of vaccine immune status in teenagers. This useful approach allows for IgG detection for vaccine control or epidemiological studies. 相似文献