Predictive power of various models for longitudinal attachment level change

Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future.     

Embedding Medical Student Computer Tutorials into a Busy Emergency Department

Objectives
To explore medical students' use of computer tutorials embedded in a busy clinical setting; to demonstrate that such tutorials can increase knowledge gain over and above that attributable to the clinical rotation itself.
Methods
Six tutorials were installed on a computer placed in a central area in an emergency department. Each tutorial was made up of between 33 and 85 screens of information that include text, graphics, animations, and questions. They were designed to be brief (10 minutes), focused, interactive, and immediately relevant. The authors evaluated the intervention using quantitative research methods, including usage tracking, surveys of faculty and students, and a randomized pretest-posttest study.
Results
Over 46 weeks, 95 medical students used the tutorials 544 times, for an overall average of 1.7 times a day. The median time spent on completed tutorials was 11 minutes (average [SD], 14 [±12] minutes). Seventy-four students completed the randomized study. They completed 65% of the assigned tutorials, resulting in improved examination scores compared with the control (effect size, 0.39; 95% confidence interval = 0.15 to 0.62). Students were positively disposed to the tutorials, ranking them as "valuable." Fifty-four percent preferred the tutorials to small group teaching sessions with a preceptor. The faculty was also positive about the tutorials, although they did not appear to integrate the tutorials directly into their teaching.
Conclusions
Medical students on rotation in a busy clinical setting can and will use appropriately presented computer tutorials. The tutorials are effective in raising examination scores.     

医院后勤服务社会化实践中的几点思考

就医院后勤服务社会化的实际操作中的几个问题进行了论述,指出实行后勤社会化服务,必须有相应的外部环境;后勤部门实行企业化管理,必须有相配套的政策作保障;实施商品化服务,必须有对等的经济意识;加大后勤服务化的力度,必须有果敢超前的决策意识。     

一种新型人TNFα对人肝癌裸鼠移植瘤的抗瘤作用

用人肝癌Ｂｅｌ７４０２瘤株建立了人肝癌裸鼠移植瘤模型，探讨新型重组人ＴＮＦａ对这种移植瘤的抗瘤作用，结果表明，ｒｈＴＦａＤ１１ａ和原型重组人ＴＮＦａ的抑瘤率在３０％左右时，后者后用的活性产闰数是前者的２倍；两者用量相同时，前者的抑产经比后者提高２３个百分     

HCMV感染动物胃肠组织损伤实验研究

目的 探讨HCMV感染是否引起大鼠和家兔胃肠组织损伤。方法 将人巨细胞病毒(Human Cyto—megalovirus，HCMV)AD168毒株静脉接种大鼠和新西兰兔，大鼠90d、兔30d后，检查动物胃、肠组织的病理变化，用免疫组化方法和原位杂交方法检查组织中的病毒抗原和DNA片段。结果 接种病毒之部分动物出现食量减少、粘液性大便，胃粘膜组织可见淋巴细胞浸润，肠粘膜变性坏死，甚至有穿孔灶；在粘膜细胞中查到病毒抗原或DNA片段。结论 HCMV感染可以侵犯动物胃肠组织并引起该组织病理损伤。     

Morphological analysis of renal cell culture models of calcium phosphate stone formation

Cell culture models of calcium phosphate renal stone formation were established using the MDCK cell line. Renal microliths were detected within pseudocysts in three-dimensional soft agar cultures, and were also observed in the basal region of cells lining the cell sheet, and immediately beneath domes or blisters in monolayers and collagen gel cultures. Light and scanning electron microscopy indicated that these microliths had a similar lamellated and spherical appearance to those in humans. These microliths were first detected microscopically after 21 days of culture, and were found to be composed of calcium phosphate by X-ray and microinfrared spectroscopic analyses. These culture models may provide a powerful new tool to study the pathogenesis of renal stone diseases and/or calcium phosphate stone formation in humans and animals.     

噪声作业工人听力影响因素的因子logistic回归分析

[目的]用因子logistic回归分析的方法探讨噪声作业工人听力的影响因素。[方法]调查某钢铁企业的2 491名噪声作业工人,对可能影响听力结果的13项指标进行研究,找出其公因子再与电测听结果作逐步logistic回归分析。[结果]血压、烟酒嗜好、日均接触时间、噪声接触、心脏功能、症状等6个回归因子对作业工人听力有一定的影响。[结论]噪声作业工人应减少不良嗜好,加强个体防护。     

慢性酒精中毒酒戒断的震颤谵妄发作危险因素探析

目的探讨慢性酒精中毒患者发生震颤谵妄(DT)的高危因素。方法把148例慢性酒精中毒患者按入院后是否出现震颤谵妄分为震颤谵妄组(DT)和非震颤谵妄组(NDT),观察他们的人口学资料(如性别、年龄、民族、婚姻状态等)、饮酒依赖史(饮酒的年限、饮酒品种、饮酒量、戒酒史等)、既往史、个人史、家族史、入院时的体征和症状(包括生命体征、戒断症状等)和身体状况等项目,描绘其临床特征,并对23项变量进行Logistic回归分析,筛选出慢性酒精中毒患者发生震颤谵妄的高危险因素。结果148例慢性酒精中毒患者在住院期间发生震颤谵妄者共28例(占18.92%)。Logistic regression model结果显示慢性酒中毒者入院后发生震颤谵妄的具有显著相关意义的5个解释变量,即入院时观察指标中的急性感染疾病、心动过速、紧张焦虑状态、精神运动性兴奋和肝功能异常。结论出现震颤谵妄的慢性酒精中毒患者与未发生震颤谵妄的慢性酒精中毒患者在入院时的临床特征存在差异,对慢性酒精中毒患者入院时及之后监测急性感染疾病、心动过速、精神运动性兴奋、紧张焦虑状态和肝功能异常等5个高危因素,有利于及时有效的干预。     

静脉内毒瘾者HIV感染的转归及影响因素

对ＨＣＶ血清标记阳性的静脉内毒瘤者进行半年和１５个月随访，并调查影响转归的部分因素。结果显示，静脉内毒瘾者抗－ＨＣＶ自然转阴率分别为１１．０／和３３．３％。单因素和多因素分析均提示转阴率以婚姻状况良好的已婚者较离婚者高、人均年收入高者较低者高，说明婚姻状况和人们的经济水平对毒瘾者抗－ＨＣＶ转阴有一定的影响。