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Event‐related potentials (ERPs) are used extensively to investigate the neural mechanisms of attention control and selection. The univariate ERP approach, however, has left important questions inadequately answered. We addressed two questions by applying multivariate pattern classification to multichannel ERPs in two cued visual spatial attention experiments (N = 56): (a) impact of cueing strategies (instructional vs. probabilistic) on attention control and selection and (b) neural and behavioral effects of individual differences. Following cue onset, the decoding accuracy (cue left vs. cue right) began to rise above chance level earlier and remained higher in instructional cueing (~80 ms) than in probabilistic cueing (~160 ms), suggesting that unilateral attention focus leads to earlier and more distinct formation of the attention control set. A similar temporal sequence was also found for target‐related processing (cued target vs. uncued target), suggesting earlier and stronger attention selection under instructional cueing. Across the two experiments: (a) individuals with higher cue‐related decoding accuracy showed higher magnitude of attentional modulation of target‐evoked N1 amplitude, suggesting that better formation of anticipatory attentional state leads to stronger modulation of target processing, and (b) individuals with higher target‐related decoding accuracy showed faster reaction times (or larger cueing effects), suggesting that stronger selection of task‐relevant information leads to better behavioral performance. Taken together, multichannel ERPs combined with machine learning decoding yields new insights into attention control and selection that complement the univariate ERP approach, and along with the univariate ERP approach, provides a more comprehensive methodology to the study of visual spatial attention.  相似文献   
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Background

Lung ultrasound can accelerate the diagnosis of life-threatening diseases in adults with respiratory symptoms.

Objective

Systematically review the accuracy of lung ultrasonography (LUS) for emergency diagnosis of pneumonia, acute heart failure, and exacerbation of chronic obstructive pulmonary disease (COPD)/asthma in adults.

Methods

PubMed, Embase, Scopus, Web of Science, and LILACS (Literatura Latino Americana e do Caribe em Ciências da Saúde; until 2016) were searched for prospective diagnostic accuracy studies. Rutter-Gatsonis hierarchical summary receiver operating characteristic method was used to measure the overall accuracy of LUS and Reitsma bivariate model to measure the accuracy of the different sonographic signs. This review was previously registered in PROSPERO (Centre for Reviews and Dissemination, University of York, York, UK; CRD42016048085).

Results

Twenty-five studies were included: 14 assessing pneumonia, 14 assessing acute heart failure, and four assessing exacerbations of COPD/asthma. The area under the summary receiver operating characteristic curve of LUS was 0.948 for pneumonia, 0.914 for acute heart failure, and 0.906 for exacerbations of COPD/asthma. In patients suspected to have pneumonia, consolidation had sensitivity of 0.82 (95% confidence interval [CI] 0.74–0.88) and specificity of 0.94 (95% CI 0.85–0.98) for this disease. In acutely dyspneic patients, modified diffuse interstitial syndrome had sensitivity of 0.90 (95% CI 0.87–0.93) and specificity of 0.93 (95% CI 0.91–0.95) for acute heart failure, whereas B-profile had sensitivity of 0.93 (95% CI 0.72–0.98) and specificity of 0.92 (95% CI 0.79–0.97) for this disease in patients with respiratory failure. In patients with acute dyspnea or respiratory failure, the A-profile without PLAPS (posterior-lateral alveolar pleural syndrome) had sensitivity of 0.78 (95% CI 0.67–0.86) and specificity of 0.94 (95% CI 0.89–0.97) for exacerbations of COPD/asthma.

Conclusion

Lung ultrasound is an accurate tool for the emergency diagnosis of pneumonia, acute heart failure, and exacerbations of COPD/asthma.  相似文献   
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阳洁  陈宏 《现代肿瘤医学》2020,(7):1209-1213
WT1基因位于人类染色体11p13,在80%的急性髓系白血病(acute myeloid leukemia,AML)患者中高表达,是AML预后不良的分子标志,可作为AML预后评估和微小残留病变(minimal residual disease,MRD)监测的有效指标。由于WT1在AML中均有异常高表达,故认为是一种AML抗原,可作为特异性免疫治疗的新靶点。一些小规模的临床试验证实以WT1为靶点的免疫治疗是有效的、安全的,这些免疫治疗可作为那些有高危复发风险及初始标准化疗失败的AML患者的辅助治疗。本文就近几年WT1与AML的预后及有关以WT1为靶点的主动特异性免疫治疗的研究进展予以综述。  相似文献   
88.
ObjectivesSevere acute kidney injury (AKI) is a known risk factor for infection and mortality. However, whether stage 1 AKI is a risk factor for infection has not been evaluated in adults. We hypothesized that stage 1 AKI following cardiac surgery would independently associate with infection and mortality.MethodsIn this retrospective propensity score–matched study, we evaluated 1620 adult patients who underwent nonemergent cardiac surgery at the University of Colorado Hospital from 2011 to 2017. Patients who developed stage 1 AKI by Kidney Disease Improving Global Outcomes creatinine criteria within 72 hours of surgery were matched to patients who did not develop AKI. The primary outcome was an infection, defined as a new surgical-site infection, positive blood or urine culture, or development of pneumonia. Secondary outcomes included in-hospital mortality, stroke, and intensive care unit (ICU) and hospital length of stay (LOS).ResultsStage 1 AKI occurred in 293 patients (18.3%). Infection occurred in 20.9% of patients with stage 1 AKI compared with 8.1% in the no-AKI group (P < .001). In propensity-score matched analysis, stage 1 AKI independently associated with increased infection (odds ratio [OR]; 2.24, 95% confidence interval [CI], 1.37-3.17), ICU LOS (OR, 2.38; 95% CI, 1.71–3.31), and hospital LOS (OR, 1.30; 95% CI, 1.17-1.45).ConclusionsStage 1 AKI is independently associated with postoperative infection, ICU LOS, and hospital LOS. Treatment strategies focused on prevention, early recognition, and optimal medical management of AKI may decrease significant postoperative morbidity.  相似文献   
89.
目的观察改良俯卧位对俯卧位通气(PPV)临床疗效及并发症的影响。方法将该院呼吸和危重症医学科行PPV的52例患者随机分为对照组和实验组各26例,对照组应用常规方法进行PPV,实验组采用改良俯卧位进行PPV。比较两组患者PPV的临床效果和并发症发生情况。结果两组间俯卧位前和俯卧位后12 h的氧合指数无明显差异(P>0.05);两组患者俯卧位后12 h的氧合指数均较各组俯卧位前明显改善(P<0.05);两组患者气管插管脱出、血流动力学显著波动、误吸和面部水肿的发生率无显著差异(P>0.05);实验组皮肤压疮的发生率明显低于对照组(P<0.05)。结论改良俯卧位对PPV的临床疗效无显著影响,但可以降低皮肤压疮的发生率。  相似文献   
90.
目的总结并归纳护理干预对急性心肌梗死患者负性情绪的影响。方法本文挑选100例医院急性心肌梗死患者(2017年2月—2018年2月)为对象。按建档时间分组,对照组50例患者(常规护理),分析组50例患者(加用人文性护理)。比较两组对疾病的了解程度及护理前后焦虑、抑郁等负性情绪的评分,随访1年,比较两组复发率。结果护理后分析组对疾病了解程度高于对照组(P<0.05);护理前分析组焦虑、抑郁评分同对照组无显著差异(P>0.05),提示可比;护理后,分析组焦虑、抑郁评分低于对照组(P<0.05);护理后分析组1年内复发率(8.00%)低于对照组(24.00%)(P<0.05)。结论在急性心肌梗死患者的护理中,人文性护理干预可显著改善患者负性情绪,改善患者预后,且可有效降低患者复发率。  相似文献   
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