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101.
Previous studies observed that most COVID-19 infections were transmitted by a few individuals at a few high-risk places (e.g., bars or social gathering venues). These individuals, often called superspreaders, transmit the virus to an unexpectedly large number of people. Further, a small number of superspreading places (SSPs) where this occurred account for a large number of COVID-19 transmissions. In this study, we propose a spatial network framework for identifying the SSPs that disproportionately spread COVID-19. Using individual-level activity data of the confirmed cases in Hong Kong, we first identify the high-risk places in the first four COVID-19 waves using the space-time kernel density method (STKDE). Then, we identify the SSPs among these high-risk places by constructing spatial networks that integrate the flow intensity of the confirmed cases. We also examine what built-environment and socio-demographic features would make a high-risk place to more likely become an SSP in different waves of COVID-19 by using regression models. The results indicate that some places had very high transmission risk and suffered from repeated COVID-19 outbreaks over the four waves, and some of these high-risk places were SSPs where most (about 80%) of the COVID-19 transmission occurred due to their intense spatial interactions with other places. Further, we find that high-risk places with dense urban renewal buildings and high median monthly household rent-to-income ratio have higher odds of being SSPs. The results also imply that the associations between built-environment and socio-demographic features with the high-risk places and SSPs are dynamic over time. The implications for better policymaking during the COVID-19 pandemic are discussed.  相似文献   
102.
ObjectivesTo systematically review and synthesize the evidence on differential associations between antihypertensive medication (AHM) classes and the risk of incident dementia.DesignSystematic review and random effects frequentist network meta-analysis. Embase, MEDLINE, and the Cochrane library were searched from origin to December 2019.Setting and participantsRandomized controlled trials (RCTs) and prospective cohort studies that compared associations of different AHM classes with incident all-cause dementia and/or Alzheimer's disease over at least 1 year of follow-up.MeasuresAll cause dementia and/or Alzheimer's disease.ResultsFifteen observational studies and 7 RCTs were included. Data on AHM classes were available for 649,790 participants and dementia occurred in 19,600 (3.02%). Network meta-analysis showed that in observational studies, treatment with either calcium channel blockers (CCBs) or angiotensin II receptor blockers (ARBs) was associated with lower dementia risks than treatment with other antihypertensives: CCBs vs angiotensin converting enzyme inhibitors (ACE inhibitors) (HR=0.84, 95% CI 0.74-0.95), beta blockers (HR=0.83, 95% CI 0.73-0.95) and diuretics (HR=0.89, 95% CI 0.78-1.01) and ARBs vs ACE inhibitors (HR=0.88, 95% CI 0.81-0.97), beta blockers (HR=0.87, 95% CI 0.77-0.99), and diuretics (HR=0.93, 95% CI 0.83-1.05). There were insufficient RCTs to create a robust network based on randomized data alone.Conclusions and ImplicationsRecommending CCBs or ARBs as preferred first-line antihypertensive treatment may significantly reduce the risk of dementia. If corroborated in a randomized setting, these findings reflect a low-cost and scalable opportunity to reduce dementia incidence worldwide.  相似文献   
103.
目的 了解长沙市大学生男男性行为人群(men who have sex with men, MSM)的社会网络特征与多性伴之间的相关性,为制定更有针对性的艾滋病防治措施提供科学依据。 方法 运用横断面研究设计,于2017年9月—2018年3月,在长沙市通过连续样本抽样及滚雪球抽样法招募大学生MSM,并进行匿名问卷调查。 结果 有效调查214人,共提名800名社交网络成员和430名性网络成员。多性伴MSM占47.6%。社交网络大小、社交网络密度的中位数和四分位数分别为6(3.75, 6)、0.1(0, 0.5)。性网络大小的中位数和四分位数为2(2,3),性网络密度为0。经多因素logistic回归分析发现,做过HIV检测(OR=2.688, 95%CI:1.336~5.407)、有偶然性伴 (OR=2.409, 95%CI=1.619~3.583)、社交网络大于5人(OR=2.163, 95%CI=1.093~4.280)、性网络与社交网络重合程度高者(OR=0.624, 95%CI=0.412~0.945),有2个或以上性伴的可能性大。 结论 大学生MSM多性伴行为普遍,且与部分社会网络特征相关,建议通过同伴进行社会网络干预,预防大学生MSM群体中HIV传播。  相似文献   
104.
按照世界卫生组织医疗器械技术序列《采购流程与资源指南》中医疗器械标准购置流程,以微型卫生技术评估(Mini-HTA)、VAC价值分析评估以及项目评估模型为依据,建立了标准且完整的医疗设备医院层级准入评估模型。该模型主要包括技术评估、效益评估、安全评估以及附件因素评估等四项指标,以实际证据为依据,采用定性、定量相结合的方式对医疗设备进行评估。应用该模型,对医院2019年50万元以上医疗设备进行准入评估,认为可有效优化医院资源配置,为医疗设备购置决策提供依据。  相似文献   
105.
依据《医疗器械临床试验质量管理规范》,参考丹麦卫生技术评估中心制定的Mini-卫生技术评估清单,结合医院实际,建立了医疗器械临床试验准入评估模型。该模型主要包括医院评估、器械评估、患者评估、机构评估及经济评估等5项指标、26项内容。实际应用中,确保了所承接的临床试验能在规定时间节点内顺利完成,并保障了试验质量和受益者权益。  相似文献   
106.
【目的】 检验引文归一化指标RCR与Scopus的FWCI指标及同行评议指标F1000之间的相关性,为引文归一化学科影响力评价实践提供理论支撑。【方法】 选取国际干细胞研究领域的学术论文为研究样本,采用正态性检验及相关性分析法研究论文的RCR指标、FWCI指标及F1000推荐次数、F1000评分之间的相关关系。【结果】 RCR指标与FWCI指标具有较强的相关性,而RCR指标与F1000推荐次数和F1000评分之间仅低度相关。【结论】 作为学科归一化指标,RCR与FWCI指标在论文影响力评价上具有一致性,但与同行评议指标F1000相关性较弱。未来,RCR指标在我国交叉学科期刊评价、建立我国科技期刊影响力评价基准、构建我国科技期刊动态评价系统方面具有较大借鉴意义。  相似文献   
107.
Erectile dysfunction is considered an important health problem that impacts the quality of life of men. Yinyanghuo, also called Epimedium or Horny Goat Weed, is a frequently used Chinese traditional herbal medicine, commonly used in treating erectile dysfunction in China. A network pharmacology method was performed systematically, at a molecular level, to analyse the pharmacological mechanism of Yinyanghuo as erectile dysfunction therapy. The network pharmacology method used in this study primarily includes prescreening of the active compounds, prediction of targets, network analysis and gene enrichment analysis. This network analysis proved that 4 targets (AR, NR3C2, PDE5A and BMP2) could be the targets of Yinyanghuo therapy on erectile dysfunction. Besides, gene enrichment analysis predicted that Yinyanghuo might have a role in erectile dysfunction by regulating 10 molecular functions, 8 cellular components, 10 biological processes and 36 possible targets related to 10 signalling pathways. Our study demonstrated the molecular and pharmacological mechanisms of Yinyanghuo against erectile dysfunction with a holistic approach and demonstrated a powerful method for analysing pharmacological mechanisms and rational utilisation of Traditional Chinese Medicine clinically.  相似文献   
108.
The present study aimed to investigate the molecular mechanism of the Astragalus–Scorpion drug pair in the treatment of prostate cancer (PCa). We employed network pharmacology and molecular docking technology to retrieving the active ingredients and corresponding targets of Astragalus–Scorpion by using TCMSP, BATMAN-TCM, TCMID and Swiss Target Prediction Databases. The targets related to PCa were retrieved through GeneCards. Cytoscape software was used to construct the ‘active ingredient–target disease’ network, and GO and KEGG enrichment analyses were performed on the common targets. Autodock software was used for molecular docking verification. In total, 26 active ingredients, 340 potential targets related to active ingredients and 122 common targets were screened from Astragalus–Scorpion drug pair. The core targets of the protein–protein interaction (PPI) network were JUN, AKT1, IL6, MAPK1 and RELA, whereas the core active ingredients were quercetin, kaempferol, formononetin, 7-o-methylisomucronulatol and calycosin. Nearly 762 GO entries and 154 pathways were obtained by using the pathway enrichment analysis. Molecular docking results revealed that quercetin and kaempferol bind to AKT1 and formononetin binds to RELA, all of which were found to be stable bounds.  相似文献   
109.
110.
目的:使用反向传播(BP)人工神经网络结合正交试验优化荷叶降脂方中药物的提取工艺,为药物的规范化生产和产业化形成提供可靠的研究基础。方法:采用水回流提取法提取,以荷叶碱的含量为评价指标,以正交试验设计筛选提取工艺,并将正交试验层次分析法得到的实验数据作为反向神经网络的输入层,评价指标的综合得分作为网络的输出层,对主要影响因素进行仿真优化,得到最优提取工艺。结果:优化得到的提取工艺条件为12倍量水、提取3次、0.5 h/次。结论:BP人工神经网络结合正交试验方法可用于荷叶降脂方提取工艺的优化,科学合理,稳定可行,符合中药制剂研发的需求。  相似文献   
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