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1.
In clinical and epidemiological studies, there is a growing interest in studying the heterogeneity among patients based on longitudinal characteristics to identify subtypes of the study population. Compared to clustering a single longitudinal marker, simultaneously clustering multiple longitudinal markers allow additional information to be incorporated into the clustering process, which reveals co-existing longitudinal patterns and generates deeper biological insight. In the current study, we propose a Bayesian consensus clustering (BCC) model for multivariate longitudinal data. Instead of arriving at a single overall clustering, the proposed model allows each marker to follow marker-specific local clustering and these local clusterings are aggregated to find a global (consensus) clustering. To estimate the posterior distribution of model parameters, a Gibbs sampling algorithm is proposed. We apply our proposed model to the primary biliary cirrhosis study to identify patient subtypes that may be associated with their prognosis. We also perform simulation studies to compare the clustering performance between the proposed model and existing models under several scenarios. The results demonstrate that the proposed BCC model serves as a useful tool for clustering multivariate longitudinal data.  相似文献   
2.
In this study, 4H-SiC p–n junctions were irradiated with 700 keV He+ ions in the fluence range 1.0 × 1012 to 1.0 × 1015 ions/cm2. The effects of irradiation were investigated by current–voltage (I–V) and capacitance–voltage (C–V) measurements, while deep-level transient spectroscopy (DLTS) was used to study the traps introduced by irradiation defects. Modifications of the device’s electrical performances were observed after irradiation, and two fluence regimes were identified. In the low fluence range (≤1013 ions/cm2), I–V characteristics evidenced an increase in series resistance, which can be associated with the decrease in the dopant concentration, as also denoted by C–V measurements. In addition, the pre-exponential parameter of junction generation current increased with fluence due to the increase in point defect concentration. The main produced defect states were the Z1/2, RD1/2, and EH6/7 centers, whose concentrations increased with fluence. At high fluence (>1013 ions/cm2), I–V curves showed a strong decrease in the generation current, while DLTS evidenced a rearrangement of defects. The detailed electrical characterization of the p–n junction performed at different temperatures highlights the existence of conduction paths with peculiar electrical properties introduced by high fluence irradiation. The results suggest the formation of localized highly resistive regions (realized by agglomeration of point defects) in parallel with the main junction.  相似文献   
3.
BackgroundA bleeding episode may herald cancer in the general population. Oral anticoagulants (OACs), the mainstay treatment for atrial fibrillation (AF), are known to increase the risk of bleeding, and may thus promote an earlier diagnosis of cancer. Data regarding the association of bleeding episodes with cancer in patients with AF on OACs are scarce.MethodsIn this systematic review and meta-analysis, we searched electronic databases (Medline, Scopus, and Central) and gray literature sources for studies of patients with nonvalvular AF under any OAC, from inception until 14 October 2020. The primary outcome was the association of bleeding occurrences with the detection of cancer. A subgroup analysis was performed according to OAC type [NOAC (non-vitamin K oral anticoagulant) versus VKA (vitamin K antagonist)].ResultsOverall, 4 studies were included, accounting for a total of 144,362 patients with AF receiving OAC. During follow-up, 816 (0.57%) cases of cancer were confirmed. The presence of a bleeding event, either major or minor, was associated with a higher risk for cancer detection (odds ratio [OR] 8.79, 95% confidence interval [CI] 4.98-15.51, and I2 85%). Heterogeneity was explained after studies were stratified by the type of OAC (NOACs: OR 6.12, 95% CI 4.47-8.37, I2 0%, VKAs: OR 15.16, 95% CI 12.61-18.23, and I2 0%).ConclusionThe detection of a bleeding event could be an alerting sign of cancer in patients with AF on OACs, particularly in patients receiving VKAs.Registration number (DOI)available in https://doi.org/10.17605/OSF.IO/3948R, DOI: 10.17605/OSF.IO/3948R.  相似文献   
4.
BackgroundIn Ontario, Canada, little is currently known about the extent to which un-immunized children may cluster geographically. Our objectives were to: describe the geographic distribution of fully un-immunized children; identify geographic clusters (hotspots) of un-immunized children; and to characterize the contribution of spatial effects and covariates on hotspots, where found.MethodsOur analytic cohort consisted of Ontario students aged 7–17 years in the 2016–2017 school year. We defined students as un-immunized if they had zero doses of any vaccine and a non-medical exemption recorded in Ontario’s registry. We calculated unadjusted proportions of un-immunized students by Census Subdivision (CSD) and then used a sequential approach to identify hotspots starting first with hotspot identification at the CSD level and then probed identified hotspots further by Dissemination Area (DA) and including covariates. Hotspots were identified using the Besag-York-Mollie Bayesian spatial model and were defined as areas with >95% probability of having two times the proportion of un-immunized students, relative to the province overall.ResultsWe identified 15,208 (0.94%) un-immunized children within our cohort consisting of more than 1.61 million students. Unadjusted proportions of un-immunized students varied greatly by geography, ranging from 0% to 21.5% by CSD. We identified 16 hotspot CSDs which clustered in five distinct areas, all of which were located in southern Ontario. The contribution of covariates and spatial effects on the risk of having un-immunized students varied greatly across hotspot areas.ConclusionsAlthough the provincial proportion (0.94%) of un-immunized students is small, geographical clustering of such students is evident in Ontario and in some areas presents an important risk for future outbreaks. Further qualitative work within these hotspot areas would be a helpful next step to better characterize the factors associated with vaccine refusal in these communities.  相似文献   
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6.
目的 对支气管扩张症的中医证候特征进行探究。方法 基于2 907例支气管扩张症住院患者的电子病历数据,运用Lantern 5.0和SPSS 20.0软件分别进行频次描述性统计、隐结构及系统聚类分析,综合判断潜在证型,为提出支气管扩张症的临床常见中医证型提供依据。结果 纳入的2 907份病历记录中涉及43个证型,其中频率大于5%的有痰热蕴肺证(52%)、痰湿阻肺证(25.5%)、肺气阴两虚证(9.1%)、痰瘀阻肺证(7.8%)、肺脾气虚证(7.1%)、肺肾气虚证(6.6%);共记录有219个症状,将出现频次>30次的67个症状作为显变量,综合聚类成风热犯肺证、痰热蕴肺证、痰湿阻肺证、痰瘀阻肺证、阴虚肺热证、肺肾气虚证、肺脾气虚证、肺气阴两虚证共8个证候;对频次>60次的52个症状进行系统聚类分析,得到风热犯肺证、痰热蕴肺证、痰湿阻肺证、肺气阴两虚证、肺脾气虚兼外感证、阴虚内热兼血瘀证、肺肾气虚证、脾气虚证、兼证络伤咳血证共10个证候。以上3种方法推断出的证型中,重复出现至少两次的证型共有8个,即可认定为支气管扩张症常见证型。结论 支气管扩张症8个常见的证型为风热犯肺证、痰热蕴肺证、痰湿阻肺证、痰瘀阻肺证、阴虚肺热证、肺肾气虚证、肺脾气虚证、肺气阴两虚证。  相似文献   
7.
[摘要] 目的 运用熔解曲线间隔区寡核苷酸分型(melting curve spacer oligonucleotide typing, McSpoligotyping)方法对宜昌地区耐多药结核分枝杆菌进行基因分型,以评价其在结核病流行病学调查中的应用价值。方法 选择2019年1月—2020年12月耐多药菌株77株作为实验组,并以异烟肼和利福平敏感菌株110株作为对照组,运用McSpoligotyping方法进行基因分型,将分型结果与SpolDB4.0数据库进行比对分析。结果 187株菌株中北京基因型116株(62.03%),非北京基因型71株(37.97%)。对照组110株中北京基因型60株(54.55%),其中数量最多的1组国际型别编码(spoligotype inter-national type, SIT)为1的北京基因型共44株(40.00%);非北京基因型50株(45.45%),以T族、Manu族常见。实验组77株中北京基因型56株(72.73%),其中数量最多的1组为 SIT为1的北京基因型共44株(57.14%),非北京基因型21株(27.27%),以T族、Manu2族常见。实验组北京基因型菌株所占比例与对照组差异有统计学意义。实验组成簇率(79.22%)与对照组成簇率(79.09%)差异无统计学意义。结论 北京基因型菌株是宜昌地区结核病的主要流行菌株,在耐多药结核病患者中北京基因型菌株更为流行。耐多药结核菌株有一定的遗传多态性。McSpoligotyping方法操作简单、快速、对于结核病分子流行病学研究具有重要意义。  相似文献   
8.
本文内容来源于2022年7月22日由上海市医师协会、上海市医师协会全科医师分会主办的"第二届海上全科医师论坛",主要包括《基层医疗在整合医疗中的作用》《创建全科医学科为国家临床重点专科》《上海市基层卫生发展趋势》《拥抱变化,更好更强》四部分。其中,《基层医疗在整合医疗中的作用》从整合程度、整合层面、整合方向3个维度阐释了"整合医疗"的概念与内涵,并就整合医疗在制度、管理、支付、服务模式、技术应用5个层面的实现路径做了详细介绍;在分析基层医疗和整合医疗共性特征的基础上,阐释基层医疗在上述5个层面对整合医疗的助推作用。《创建全科医学科为国家临床重点专科》从全科医学科在卫生保健改革、满足居民卫生服务需求中的重要作用出发,阐述了创建全科医学科为国家临床重点专科的必要性,认为创建临床重点专科需做到:提高全科医学科学术地位,推进全科医学人才建设,提升全科医学科区域协同能力,形成全方位全周期健康照护专科特色,加快全科医学科研创新发展。《上海市基层卫生发展趋势》肯定了基层卫生对城市健康发展的贡献,提出在"大健康"的背景下进一步的重点工作为推进健康老龄化和实现出生人口提升计划;上海基层卫生的发展趋势在于创新,而基层卫生高质量发展工作的创新需要由全科医生作为推动者和牵头者,创造出新的健康服务模式。《拥抱变化,更好更强》,认为当前社区卫生服务的"薄弱"之处,并非发展之初的硬件或人员配置不足,而是体现在全科学科建设方面。全科医学领域工作者应主动面对和接纳当前国家健康战略的变化、健康需求的变化、医学模式的变化、自身发展/管理的变化,开展主动健康,应对多病共存,加强全-专结合,关注需方角度的服务评价,以助力全科医学学科建设。  相似文献   
9.
以PubMed收录的药物重定位相关文献为数据来源,提取主要主题词进行频次统计,生成高频主题词-论文矩阵进行聚类分析,结果表明当前药物重定位主要研究热点为基于疾病的药物重定位与基于生物信息学的药物重定位两个方面,具体包括5个主题方向。  相似文献   
10.
目的抑郁症状(MDD)是帕金森病(PD)常见的非运动症状,探讨帕金森病和抑郁症可能具有的共同致病机制。方法通过文本挖掘及转录组数据分析帕金森病与抑郁症共同的致病机制。结果文本挖掘发现63. 8%的MDD基因和32%的PD基因为共有基因及438个共有的生物学过程;转录组筛选出有统计学意义的10个共同差异基因:I类肌球蛋白(MYO1F)、活化免疫球蛋白样受体(LILRA2)、垂体腺苷酸环化酶激活多肽(ADCYAP1)、骨骼肌肌球蛋白轻链激酶(MYLK2)、钙结合蛋白2(CLSTN2)、钙调蛋白依赖性蛋白激酶4(CAMK4)、前蛋白转化酶枯草杆菌蛋白酶1 (PCSK1)、瞬时受体电位阳离子通道5(TRPC5)、钠离子葡萄糖联合转运子(SLC5A1)、酪氨酸酶相关蛋白1 (TYPR1)(P 0. 01);基因功能富集分析发现PD和MDD具有相同的14个生物学过程,6个细胞组成,10个分子功能,并且有3个相同的京都基因与基因组百科全书(KEGG)信号通路(P 0. 05);通过蛋白质网络构建,筛选出4个共同的关键基因(MYO1F、CAMK4、PCSK1、TRPC5);通过对蛋白质网络模块分析后发现关键模块具有共同的生物学过程。结论帕金森病和抑郁症具有共同的致病基因及通路,这为帕金森病和抑郁症伴存现象提供了理论基础。  相似文献   
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