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11.
The self is a multifaceted phenomenon that integrates information and experience across multiple time scales. How temporal integration on the psychological level of the self is related to temporal integration on the neuronal level remains unclear. To investigate temporal integration on the psychological level, we modified a well‐established self‐matching paradigm by inserting temporal delays. On the neuronal level, we indexed temporal integration in resting‐state EEG by two related measures of scale‐free dynamics, the power law exponent and autocorrelation window. We hypothesized that the previously established self‐prioritization effect, measured as decreased response times or increased accuracy for self‐related stimuli, would change with the insertion of different temporal delays between the paired stimuli, and that these changes would be related to temporal integration on the neuronal level. We found a significant self‐prioritization effect on accuracy in all conditions with delays, indicating stronger temporal integration of self‐related stimuli. Further, we observed a relationship between temporal integration on psychological and neuronal levels: higher degrees of neuronal integration, that is, higher power‐law exponent and longer autocorrelation window, during resting‐state EEG were related to a stronger increase in the self‐prioritization effect across longer temporal delays. We conclude that temporal integration on the neuronal level serves as a template for temporal integration of the self on the psychological level. Temporal integration can thus be conceived as the “common currency” of neuronal and psychological levels of self.  相似文献   
12.
Non-invasive prenatal testing (NIPT) is performed worldwide to detect common chromosomal aneuploidies. The analysis of cell-free DNA (cfDNA) in maternal blood for NIPT is highly accurate for the detection of the main fetal trisomies: 21,18, and 13. However, false-positive, false-negative, and non-reportable results can occur, and these can have biological causes. Understanding the causes of unexpected NIPT results is essential to enable clinicians and genetic counselors to counsel patients comprehensively and appropriately, both prior to testing as well as after receiving the test results. The classification of non-reportable results from cfDNA analysis is important in order to provide women with precise information. In addition to technical issues, there are biological reasons for discordant results, which can be either fetal or maternal in origin. Contributing fetal factors include insufficient or absent fetal fraction, fetoplacental mosaicism, and the presence of a vanishing twin. In some pregnant women that test positive for NIPT, multiple chromosome aneuploidy has been reported as a result of suspected malignancy, and cancer has been found. False-positive and false-negative results may be the result of placental biology and not a failure in the actual test platform. Explaining the placental origin of cfDNA provides the patient with a clear view of the abilities and limitations of cfDNA-based prenatal screening.  相似文献   
13.
The optimal management in Oligometastatic (OM) breast carcinoma is not defined.ObjectivesTo identify the prognostic factors influencing OM and the effect of Locoregional treatment (LRT) on survival in OM.MethodologyPatients with ≤5 metastases and each with ≤ 5 cm size were defined as OM. Data of OM were extracted from the Institute Registry between 2012 and 2018. The impact of prognostic factors on survival was analysed by univariate and multivariate Cox regression. The Kaplan Meier survival curves were used to plot PFS and OS.ResultsThere were 170 patients with OM. The median follow-up was 61 months. Median OS was 43.3 months. The median OS was 74 months in OMD vs 22.7 months in Oligorecurrent disease (ORD) with 5year OS rate of 55.3% vs 16.5% respectively. In the multivariate analyses of OMD both Ki67 ≤ 50% and hormone therapy (HT) showed significant favourable survival outcome. While premenopausal status and HT showed significant survival benefits in ORD. The worse survival outcome in ORD could be because of their aggressive biology and deficit in LRT compared to literature review. The prognostic factors were swayed by the uneven distribution of HR status, grade and Ki67.ConclusionThe survival of OM was influenced by OMD, Ki67 ≤ 50%, premenopausal status and HT. The lesser survival rates of OM in the long term suggest the need for curative LRT to metastatic sites and primary tumor. The potential role of HT and targeted therapy with or without LRT need to be assessed in future randomised trials.  相似文献   
14.
《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.  相似文献   
15.
目的:考察黑豆汁炖制时间对制何首乌外观性状及各类有效成分含量变化规律的影响。方法:采用HPLC同时测定不同炮制时间制何首乌样品中二苯乙烯苷、大黄素、大黄素甲醚、大黄素-8-O-β-D-葡萄糖苷、大黄素甲醚-8-O-葡萄糖苷的含量,选择Agilent ZORBAX Extend-C_(18)色谱柱(4. 6 mm×250 mm,5μm),甲醇(A)-水(B)为流动相梯度洗脱(0~30 min,5%~100%A; 30~40 min,100%A),流速1. 0 mL·min~(-1),柱温35℃,检测波长280 nm。结果:随炖制时间的增加,二苯乙烯苷含量逐渐降低,与8 h时相比,至64 h时含量降低76%;大黄素-8-O-β-D-葡萄糖苷和大黄素甲醚-8-O-葡萄糖苷2种蒽醌苷含量先上升后下降,至24 h时达最高值,炖制40 h时降至与8 h近似的水平,之后略有波动;大黄素、大黄素甲醚2种蒽醌苷元含量先上升后下降,炖制32 h时达最大值,之后缓慢降低并趋于稳定。结论:炖制时间对制何首乌中各类成分含量的影响显著,且变化趋势不尽相同,应规范制何首乌饮片的炮制时间;同时,仅以二苯乙烯苷及蒽醌类成分作为制何首乌的指标性成分依据不够充分,应考虑增加多糖类等质量控制指标。  相似文献   
16.
目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)对三阴性乳腺癌的临床预后影响及与Ki - 67表达的关系。方法 回顾性分析2006年1月 - 2012年12月于我院乳腺外科住院治疗的134例三阴性乳腺癌患者。NLR最佳临床分界值采用ROC曲线确定,并依此分NLR<2.64组和NLR≥2.64组。临床独立预后因素采用单因素和多因素Cox回归模型分析。术后生存时间和生存曲线比较采用Kaplan - Meier和log - rank方法。Ki - 67的表达采用免疫组织化学方法检测。结果 NLR是三阴性乳腺癌的独立预后因素,最佳临界值为2.64。NLR<2.64组术后中位DFS为39.10月,中位OS为52.30月;NLR≥2.64组术后中位DFS为27.35月,中位OS为37.35月。2组术后DFS和OS比较,差异具有统计学意义(P<0.05)。NLR低组伴Ki - 67表达阴性的三阴性患者术后中位DFS和OS生存时间显著高于其他情况。结论 NLR是三阴性乳腺癌的关键影响预后因素,具有重复性强、非侵袭性、方便实用等特性,可用于预测三阴性乳腺癌临床预后。  相似文献   
17.
18.
目的:探讨血小板与淋巴细胞比值(platelet to lymphocyte ratio,PLR)对三阴性乳腺癌的临床预后影响及与免疫球蛋白表达的关系。方法:回顾性分析2006年1月至2012年12月于我院乳腺外科住院治疗的134例三阴性乳腺癌患者。临床独立预后因素采用单因素和多因素Cox回归模型分析。术后生存时间和生存曲线比较采用Kaplan-Meier和log-rank方法。结果:PLR是三阴性乳腺癌的独立预后因素,最佳临界值为155.00。PLR<155.00组,术后中位DFS为35.51月,中位OS为55.24月;PLR≥155.00组,术后中位DFS为25.07月,中位OS为35.17月。两组术后DFS和OS比较,差异具有统计学意义(P<0.05)。结论:PLR是三阴性乳腺癌的独立预后因素,具有重复性强、非侵袭性、方便实用等特性,可用于预测三阴性乳腺癌临床预后。  相似文献   
19.
化学药合成过程中水分残留不利于反应的进行,还影响药物及制剂的稳定性、理化性质、溶出及药理作用等,因此水分几乎是大多数药物合成中的必测项目,通过有效除水严格控制反应体系中水分的含量至关重要。本文综述了水分的存在形式,常见除水剂和脱水剂的种类、作用原理与除水能力,以及在药物合成的应用,为药物合成反应中水分的去除提供参考。  相似文献   
20.
目的:分析布鲁菌病患者临床特征,提高对布鲁菌病的认知及诊断水平。方法:回顾性分析2014年1月至2019年3月本院明确诊断的11例布鲁菌病患者的流行病学特点、临床表现、实验室检查和流行病学资料。结果:确诊患者中,有明确牛羊动物及不熟生肉接触史者6例;临床表现为发热10例、关节痛4例、畏寒3例、头晕3例及乏力1例;实验室检查结果显示,11例确诊患者C-反应蛋白、红细胞沉降率结果均增高,谷丙转氨酶升高8例,降钙素原增高7例,血白细胞总数降低7例,淋巴细胞增高6例,血小板总数降低6例,血红蛋白降低5例;血培养送检11例,阳性8例,骨髓培养送检3例,阳性2例;随访结果表明该11例患者经内科积极治疗后均治愈。结论:对长期不明原因发热患者结合流行病学特点应考虑布鲁菌病可能,并应早期送检血培养和骨髓培养,避免漏诊和误诊,同时增强高危人群防护意识,防止暴发流行的可能。  相似文献   
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