Quantile regression and empirical likelihood for the analysis of longitudinal data with monotone missing responses due to dropout,with applications to quality of life measurements from clinical trials

The analysis of quality of life (QoL) data can be challenging due to the skewness of responses and the presence of missing data. In this paper, we propose a new weighted quantile regression method for estimating the conditional quantiles of QoL data with responses missing at random. The proposed method makes use of the correlation information within the same subject from an auxiliary mean regression model to enhance the estimation efficiency and takes into account of missing data mechanism. The asymptotic properties of the proposed estimator have been studied and simulations are also conducted to evaluate the performance of the proposed estimator. The proposed method has also been applied to the analysis of the QoL data from a clinical trial on early breast cancer, which motivated this study.     

知识点模块网格化模型在肾内科实习生带教中的应用

目的 运用知识点模块网格化构建带教模型，观察其在肾内科实习生中的应用效果。方法 根据《内科学》（第八版）肾内科教学大纲要求，结合肾内科病房常见病、多发病的临床特点，精心挑选相关知识点，以理论为支撑点，以服务于实习带教工作为靶目标，各个知识点之间有临床的关联性，最终形成网格化的诊治分 析模型。将血尿、蛋白尿、高血压、水肿、肾小球滤过率为切入点，设定肾病综合征、系统性红斑狼疮、糖尿病肾病和急、慢性肾功能衰竭为临床知识必须掌握点，从病史、症状、体征和实验室检查几方面来培养实习生的诊疗思维，并通过知识点来关联疾病的诊治，从而帮助他们在有限的肾内科实习期间尽可能掌握肾内科临床知识。结果 本研究开展一年以来，对于来肾内科轮转的51 名实习生进行了模块网格化模型训练，实习生普遍反映该模型有很好的学习效果，让他们了解了肾内科临床重点，并能和理论学习的知识点有机融合在一起，开阔了实习生的诊疗视野，也便于对其他科知识点的学习。结论 基于知识点模块网格化，构建模型在肾内科实习生中有很好的带教作用，学生接受肾内科知识点的记忆增强，并能进一步推广到内科其他内容的实习带教中。     

Cardiac Denervation for Arrhythmia Treatment with Transesophageal Ultrasonic Strategy in Canine Models

Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.     

Rural–urban disparities in knowledge,behaviors, and mental health during COVID-19 pandemic: A community-based cross-sectional survey

To examine the knowledge level, behaviors, and psychological status of the Chinese population during the COVID-19 pandemic, and to explore the differences between urban and rural areas.We carried out a cross-sectional survey of the knowledge, behaviors related to COVID-19, and mental health in a probability sample of 3001 community residents in 30 provinces or districts across China from February 16–23, 2020. Convenience sampling and a snowball sampling were adopted. We used General Anxiety Disorder (GAD), the 9-item Patient Health Questionnaire (PHQ-9), and knowledge and behaviors questionnaire of community residents regarding COVID-19 designed by us to investigate the psychological status, disease-related knowledge, and the behavior of Chinese urban and rural residents during the pandemic.The average score of anxiety and depression among urban residents was 9.15 and 11.25, respectively, while the figures in rural areas were 8.69 and 10.57, respectively. There was a statistically significant difference in the levels of anxiety (P < .01) and depression (P < .01). Urban participants reported significantly higher levels of knowledge regarding COVID-19 in all aspects (transmission, prevention measures, symptoms of infection, treatment, and prognosis) (P < .01), compared to their rural counterparts. While a majority of respondents in urban areas obtained knowledge through WeChat, other apps, and the Internet (P < .01), residents in rural areas accessed information through interactions with the community (P < .01). Urban residents fared well in exchanging knowledge about COVID-19 and advising others to take preventive measures (P < .01), but fared poorly in advising people to visit a hospital if they displayed symptoms of the disease, compared to rural residents (P < .01). Regression analysis with behavior showed that being female (OR = 2.106, 95%CI = 1.259–3.522), aged 18 ≤ age < 65 (OR = 4.059, 95%CI = 2.166–7.607), being satisfied with the precautions taken by the community (OR = 2.594, 95%CI = 1.485–4.530), disinfecting public facilities in the community (OR = 2.342, 95%CI = 1.206–4.547), having knowledge of transmission modes (OR = 3.987, 95%CI: 2.039, 7.798), symptoms (OR = 2.045, 95%CI = 1.054–4.003), and outcomes (OR = 2.740, 95%CI = 1.513–4.962) of COVID-19, and not having anxiety symptoms (OR = 2.578, 95%CI = 1.127–5.901) were positively associated with affirmative behavior in urban areas. Being married (OR = 4.960, 95%CI = 2.608–9.434), being satisfied with the precautions taken by the community (OR = 2.484, 95%CI = 1.315–4.691), screening to ensure face mask wearing before entering the community (OR = 8.809, 95%CI = 2.649–19.294), and having knowledge about precautions (OR = 4.886, 95%CI = 2.604–9.167) and outcomes (OR = 2.657, 95%CI = 1.309–5.391) were positively associated with acceptable conduct in rural areas.The status of anxiety and depression among urban residents was more severe compared to those living in rural areas. There was a difference in being positively associated with constructive behaviors between rural and urban areas.     

N-亚硝胺类基因毒性杂质的研究进展

自“缬沙坦事件”之后，N-亚硝胺类基因毒性杂质引起了业界的广泛关注。本文概述了药物中N-亚硝胺类基因毒性杂质和相关检测方法的研究进展，以及近20年来国内外有关药物中基因毒性杂质监管指南的完善历程。N-亚硝胺类基因毒性杂质作为一类高反应活性的基因毒性杂质，主要来源于药物合成过程中发生的副反应，以及药物在储存或者运输过程中发生的氧化或还原等反应。所有的动物实验表明，N-亚硝胺类具有很强的致癌性。在理论上，所有药物都存在N-亚硝胺类杂质或被N-亚硝胺类杂质污染的风险，由于该类化合物在药物中常以痕量形式存在，在分析检测过程中药物基质干扰大，因此建立便捷、高效的分析方法是非常有必要的。     

电阻抗断层成像技术在儿科呼吸系统疾病诊治中的应用

电阻抗断层成像技术(electrical impedance tomography,EIT)作为一项新兴的功能性成像技术,具有无损伤、便携、图像监护等突出特点。肺功能成像是目前EIT最主要的应用领域,可以实现实时动态监测肺通气及血流灌注。本文对肺EIT在儿童呼吸系统疾病及其诊疗过程中的应用基础及临床研究进展进行总结,为未来EIT技术在儿科临床急救领域的推广应用提供帮助。