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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   
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Most surgical and anaesthetic mortality and morbidity occurs postoperatively, disproportionately affecting low- and middle-income countries. Various short courses have been developed to improve patient outcomes in low- and middle-income countries, but none specifically to address postoperative care and complications. We aimed to identify key features of a proposed short-course addressing this topic using a Delphi process with low- and middle-income country anaesthesia providers trained as short-course facilitators. An initial questionnaire was co-developed from literature review and exploratory workshops to include 108 potential course features. Features included content; teaching method; appropriate participants; and appropriate faculty. Over three Delphi rounds (panellists numbered 86, 64 and 35 in successive cycles), panellists indicated which features they considered most important. Responses were analysed by geographical regions: Africa, the Americas, south-east Asia and Western Pacific. Ultimately, panellists identified 60, 40 and 54 core features for the proposed course in each region, respectively. There were high levels of consensus within regions on what constituted core course content, but not between regions. All panellists preferred the small group workshop teaching method irrespective of region. All regions considered anaesthetists to be key facilitators, while all agreed that both anaesthetists and operating theatre nurses were key participants. The African and Americas regional panels recommended more multidisciplinary healthcare professionals for participant roles. Faculty from high-income countries were not considered high priority. Our study highlights variability between geographical regions as to which course features were perceived as most locally relevant, supporting regional adaptation of short-course design rather than a one-size-fits-all model.  相似文献   
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目的 分析社区"5+1"糖尿病分阶段达标管理对2型糖尿病患者生存质量的干预效果及其影响因素,为提高患者生存质量提供依据。方法 采用分层整群抽样的方法在山西省、江苏省和宁夏回族自治区选择12个社区卫生服务中心,分别作为干预组(管理方式:社区"5+1"糖尿病分阶段达标管理)、对照组[管理方式:依据《国家基本公共卫生服务规范(2011年版)》的相关要求],进行为期2年的随访观察。采用面对面问卷调查的方式,收集患者的人口学信息等基本信息;采用健康调查简表(SF-36)对患者在干预前后测量生存质量。采用SAS 9.4软件进行双重差分法以及多重线性回归模型分析。结果 基线时共纳入2 467名研究对象,终末时共1 924人接受了为期2年完整的随访管理。干预后,干预组、对照组患者生理健康维度(PCS)、心理健康维度(MCS)评分变化净差值分别为13.6分、29.8分。多重线性回归分析结果显示,影响患者PCS得分的主要因素有年龄、医保类型、基线PCS得分以及所在地区,影响患者MCS得分的主要因素有年龄、医保类型、基线MCS得分、是否合并高血压以及所在地区。结论 社区"5+1"糖尿病分阶段达标管理对2型糖尿病患者生存质量的干预效果较好。  相似文献   
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我院自1989年3月至1995年10月手术治疗21例创伤性膈疝,21例疝愈。 发病机理与胸腹腔压力差、腹腔脏器冲击膈肌及胸腔负压有关。同时简要介绍了创伤性膈疝的诊断和治疗。  相似文献   
6.
中国已婚育龄妇女分娩保健服务的状况与变化研究   总被引:5,自引:0,他引:5  
目的:分析我国已婚育龄妇女分娩保健服务状况及其变化。方法:对全国31个省(直辖市、自治区)抽取的调查前三年有生育史的1962名已婚育龄妇女进行问卷调查,结合1997年全国人口与生殖健康调查资料,对两次调查前三年有生育史妇女最近一次活产的分娩保健服务状况进行比较分析。结果:①与1997年调查前三年相比,2001年调查前三年育龄妇女的入院分娩率增加,家庭分娩的比例明显减少;②农村妇女家庭分娩比例明显降低,由1997年调查时的61·41%降为2001年调查时的40·78%,1998~2000年间,92·54%城镇妇女接受分娩保健服务,农村妇女家庭分娩比例高出城镇7·4倍,为40·78%;③分娩保健服务在各地区发展不平衡,东部和中部地区发展快,西部地区,尤其是西南地区发展相对较慢,1998~2000年间,西部地区妇女中,一半以上在家分娩,西部地区农村家庭分娩妇女一半以上由家人接生,约为东部和中部地区的6倍;④少数民族妇女家庭分娩和由家人接生的比例明显高于汉族妇女;⑤随着文化程度和经济收入的增加育龄妇女对分娩保健服务的利用增加,文盲、经济收入低的妇女家庭分娩比例和由家人接生的比例非常高。结论:我国分娩保健服务状况在改善,但发展极不平衡,西部地区农村的分娩保健服务急待提高。应加强对西部地区分娩保健服务的支持力度,研究制定应对策略,加强对西部农村接生人员的专业技术培训。  相似文献   
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PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
10.
Work stress, burnout, and diminished empathy are prevalent issues for health‐care professionals. Mindfulness meditation (MM) is one commonly used strategy to manage stress. Measuring salivary cortisol allows for the assessment of serum cortisol level, a known stress level indicator. This study evaluated the association of subject‐reported stress symptoms and salivary cortisol in health‐care professionals, in an 8‐week MM program, with data collected prospectively at baseline and 8 weeks after program completion. Questionnaires [Profile of Mood States—Short Form (POMS‐SF), Maslach Burnout Inventory (MBI), and Interpersonal Reactivity Index (IRI)] measured mood, burnout and empathy. A paired t‐test between groups for pre/post‐salivary cortisol yielded no significant change. The POMS‐SF was most sensitive to change (mean increase 12.4; p = 0.020). Emotional exhaustion, measured in the MBI, was also affected by MM (mean decrease 4.54; p = 0.001). Changes in empathy may not have been captured due to either absence of effect of MM on empathy, subject number or scale sensitivity. Baseline and 8‐week correlations between salivary cortisol and survey results, and correlations between changes in these measures, were weak and not statistically significant. Nevertheless, psychometric results present a strong case for additional clinical trials of MM to reduce stress for health‐care professionals. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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