Weighted hurdle regression method for joint modeling of cardiovascular events likelihood and rate in the US dialysis population

We propose a new weighted hurdle regression method for modeling count data, with particular interest in modeling cardiovascular events in patients on dialysis. Cardiovascular disease remains one of the leading causes of hospitalization and death in this population. Our aim is to jointly model the relationship/association between covariates and (i) the probability of cardiovascular events, a binary process, and (ii) the rate of events once the realization is positive—when the ‘hurdle’ is crossed—using a zero‐truncated Poisson distribution. When the observation period or follow‐up time, from the start of dialysis, varies among individuals, the estimated probability of positive cardiovascular events during the study period will be biased. Furthermore, when the model contains covariates, then the estimated relationship between the covariates and the probability of cardiovascular events will also be biased. These challenges are addressed with the proposed weighted hurdle regression method. Estimation for the weighted hurdle regression model is a weighted likelihood approach, where standard maximum likelihood estimation can be utilized. The method is illustrated with data from the United States Renal Data System. Simulation studies show the ability of proposed method to successfully adjust for differential follow‐up times and incorporate the effects of covariates in the weighting. Copyright © 2014 John Wiley & Sons, Ltd.     

The consequences of proportional hazards based model selection

For testing the efficacy of a treatment in a clinical trial with survival data, the Cox proportional hazards (PH) model is the well‐accepted, conventional tool. When using this model, one typically proceeds by confirming that the required PH assumption holds true. If the PH assumption fails to hold, there are many options available, proposed as alternatives to the Cox PH model. An important question which arises is whether the potential bias introduced by this sequential model fitting procedure merits concern and, if so, what are effective mechanisms for correction. We investigate by means of simulation study and draw attention to the considerable drawbacks, with regard to power, of a simple resampling technique, the permutation adjustment, a natural recourse for addressing such challenges. We also consider a recently proposed two‐stage testing strategy (2008) for ameliorating these effects. Copyright © 2013 John Wiley & Sons, Ltd.     

早期2型糖尿病肾病患者社区综合干预效果分析

目的 探讨早期2型糖尿病肾病患者社区综合干预方案的实施效果.方法 对社区2型糖尿病在册管理对象中选择符合早期糖尿病肾病期诊断标准,且自愿参加的患者80例作为研究对象,实施肾病早期综合干预方案.干预12个月后对血压、空腹血糖、糖化血红蛋白、血脂及尿微量白蛋白指标进行效果评价.结果 研究对象经综合干预后其相关检测指标均比干预前有好转,经t检验分析：尿微量白蛋白、TG、HDL和LDL四项指标前后差异有极显著性意义（P＜0.01）;收缩压、舒张压、FBG、HbAlc、TL及BMI六项指标前后差异有显著性意义（P＜0.05）.结论 本研究反映在社区卫生服务中心对糖尿病伴发早期肾病患者开展综合干预是可行有效的,对控制早期糖尿病肾病患者病情的发展具有重要的影响.     

带离心功能的极坐标式移动平台的设计与分析

文章介绍了一款自动化装置的结构设计基本方案,该装置可应用在基于图像的显微病理分析中,能够对体液样本进行离心处理,并在不移动样本的情况下直接降低转速,配合沿样本平台径向直线运动的物镜,对样本进行逐格扫描.为了避免离心运动过后转速降低使得样品恢复原始状态,本文还设计了一款特殊的样本容器.该设计中还提出了一种新型微调平机构解决方案,用以调节旋转平台基准面与聚光镜发出光线的垂直度.最后通过有限元仿真软件对该机构进行模态分析.     

针灸联合康复运动治疗中风后遗症的临床分析

目的：探讨针灸联合康复运动治疗中风后遗症的临床治疗效果。方法：将82例中风后遗症患者,随机分为观察组和对照组各41例。观察组应用针灸联合康复运动治疗,对照组应用康复锻炼治疗。1个疗程为10天,3个疗程后观察患者治疗效果。结果：：两组患者在治疗3个疗程后,观察组治疗总有效率为93%;而对照组治疗总有效率为88%,明显低于观察组（p〈0.05）。结论：：中风后遗症患者治疗过程中,应用针灸联合康复运动进行治疗,具有较好临床疗效。     

脑中风患者肢体麻木康复疗法及护理措施

脑中风发病后导致患者神经不同程度的受损,加之有的患者脑血管存在狭窄等病变,导致肢体麻木。多数患者还伴有全身乏力、头昏、言语不利等并发症,需要接受系统的正规康复治疗。医护人员首先要做好患者及家属的心理护理,情绪稳定,正确对待疾病,增强战胜病魔的信念;严密观察患者各项体征指标,监督患者正常用药配合治疗;同时要做好患者及家属院外康复指导,对患者的早期康复意义重大。     

极端干旱区棉花生育期变化特征及光热条件对其产量的影响

利用敦煌市1983—2012年棉花生育期农业气象观测资料,研究不同播种期棉花的生育天数的变化以及棉花在不同阶段生育天数、气温、光照条件的差异及其对棉花产量的影响;构建了产量与生育天数、日照时数和平均气温的回归方程。结果表明：播种日期的迟早主要影响播种出苗期和苗期的生育天数,播种越迟,这两个阶段的天数越短。各发育阶段天数的变化直接影响着棉花的品质与产量,其中蕾期天数与吐絮期天数相关较好,蕾期天数短,吐絮期天数长,利于棉花的生长发育。近30 a来,日平均和总日照时数均有所增加,气候倾向率分别为0.12 h·10a^-1和96.14 h·10a^-1;平均气温呈上升趋势,气候倾向率达0.29 ℃·10a^-1,近代气候光热条件的变化对喜热植物棉花是十分有利的。在不同生育阶段,棉花对光热条件的需求各异,如吐絮期的日照时数越多、气温越高,则越容易获得高产。根据早熟及抗病为主的品种对发育天数和光热条件的需求,结合当地气候,合理确定播种期,科学地利用气候因子对棉花各生育期的影响,是实现棉花高质高产的有效途径。     

Are patient educational resources effective at deterring stroke survivors from considering experimental stem cell treatments? A randomized controlled trial

ObjectiveTo evaluate whether online resources developed to educate people about the risks associated with experimental stem cell (SC) treatments influence stroke survivors’ attitudes about the safety and effectiveness of these treatments.MethodsAdult stroke survivors who had not previously received SC treatments (N = 112) were recruited from international stroke advocacy/support groups for a prospective, parallel-group randomized controlled trial. Participants indicated whether they were considering SC treatments (yes/no) prior to, immediately following, and 30-days after reading/viewing the International Society for Stem Cell Research booklet or Stem Cell Network video. Participant attitudes regarding the safety, effectiveness, accessibility and affordability of SC treatments were examined on each occasion, and compared to those of a waitlist control group.ResultsSignificantly fewer participants were considering SC treatments immediately after reading the SC research booklet (p =.031), although neither intervention had any impact after 30-days (p >.05). Waitlist and intervention groups reported positive attitudes toward SC treatments at each assessment.ConclusionsStroke survivor attitudes toward SC treatments were initially influenced by the patient booklet, however these changes were not maintained.Practical ImplicationsClinicians are encouraged to initiate discussions about experimental SC treatments during inpatient rehabilitation and to reinforce the risks throughout subsequent care.