骨重建数值仿真中的控制方程

人体骨组织有着复杂的结构和生理机制,骨重建理论经历了定性分析、定量计算和计算机定量数值模拟三个阶段。目前,存在力学模型和现象模型两类成熟的骨重建模型,力学模型的共性就是表观密度随一定的力学刺激而变化,现象模型由基本多细胞单元的损伤状态和孔隙度变化来决定。大多数股骨重建仿真模型仍然将骨量的分布看作是各向同性的,这就不能完全反映骨组织微构造的本构关系。本文是对骨重建仿真模型的控制方程进行综述。     

多参数信息融合实现非脑电的睡眠结构分期

目前临床睡眠分析的主要手段是多导睡眠图（Polysomnograph,PSG）,用仪器记录被测者整晚的脑电、眼动电和颏肌电等生理参数,计算机进行自动睡眠分期,再由技术人员依据国际标准进行校正.几十年来PSG保持着睡眠分期金标准的地位.提出在不使用脑电的条件下,利用较易获得的心动周期、呼吸、体动等基本生理参数,提取其中与睡眠过程及其变化有关的规律和信息,建立知识规则库,采用不确定推理的证据理论进行多参数睡眠信息融合计算,实现睡眠结构分期.50余例与PSG对照试验结果表明：醒睡的平均符合率达90%以上,基本睡眠结构的平均符合率达75%以上,证明该技术达到了应用的要求.     

A comparison of the Fishbein and Ajzen and the Triandis attitudinal models for the prediction of exercise intention and behavior

The main purpose of the study was to compare the efficiency of the Fishbein and Ajzen and the Triandis models to predict (1) the intention to participate regularly in some physical activities during free time within a 3-week period and (2) the exercise behavior within these 3 weeks among a group of 166 subjects, aged 22 to 65 years. Our results show that the Triandis model was as efficient as the Fishbein and Ajzen model in predicting the exercise behavior. However, the results obtained from the Triandis model demonstrate the importance of the habit of exercising in predicting the exercise behavior. Moreover, the Triandis model was superior to the Fishbein and Ajzen model in explaining behavioral intention. Of particular interest was the salience of the affective, social, and personal belief components of the Triandis model. In addition, from a practical perspective, this comparative study showed that (1) to exercise regularly is perceived as hard work, and (2) individuals believe that it is their own responsibility to exercise or not to exercise.     

任务的呈现方式对孤独症儿童误念理解的影响

目的:探讨一种更适于测试孤独症儿童误念理解能力的方法.方法:2(呈现方式)×2(被试类型)设计,采用经典误念任务,使用计算机多媒体动画呈现方式与传统图片-实物呈现方式,分别测试20名孤独症儿童和言语能力(PPVT-R)匹配的正常儿童.结果:呈现方式的主效应非常显著(P<0.001),动画呈现方式使正常儿童和孤独症儿童的误念理解成绩都有提高,孤独症儿童的提高更大.结论:孤独症儿童的误念理解能力在误念任务的传统呈现方式之下可能被低估了.充分考虑孤独症认知缺陷的多样性,使用恰当的任务方式,可能会更真实地反映他们的心理理论发展水平.     

Childless elderly: Theoretical perspectives and practical concerns

Almost nothing is concretely known about childless elderly in cross-cultural perspective. Few published papers have appeared on this social category in the West, although childless elders make up (at least) 20% of the population of elderly in many Western nations. Little is known about childless elderly in the Third World. This paper provides some theoretical background to the study of childless elderly and articulates some social policy concerns about them. It suggests that there are five important questions to examine concerning the lives of childless elderly. These include, how childless aged are or are not provided for in societies in which a great deal of the care of the aged is undertaken by children; how kinship functions as a matrix for care; how the increasingly common phenomenon of voluntary childless may give meaning to childlessness in late life; how childlessness fits with such social science models such as the developmental cycle; and, the relationship of this phenomenon to changing opportunities for women. The paper further examines how factors such as fertility, systems of caregiving, the social meaning of childlessness, alternatives to childlessness such as adoption, and educational and economic opportunities may affect the lives of childless elders.     

Radiographic quantification of alveolar bone level changes

The "random burst" theory has recently been proposed as an explanation of the pattern of periodontal disease progression. The theory predicts that the progression of bone loss at individual sites is not dependent upon previous bone loss and age. A longitudinal radiographic study was designed to test this hypothesis, and to describe the changes in bone level over 2 years in a group of 180 subjects (18-68 years of age) who were not under systematic periodontal treatment. The results indicated that 94% of the sites did not show significant changes in the alveolar bone level during the observation period. The mean annual bone loss for the total population was 0.11 mm. By regressing longitudinal bone loss upon age, it was shown that the rate of bone loss increased rapidly between 33 and 56 years of age while a different pattern was shown for the age intervals 18-32 and 57-68 years. Also, the rate of bone loss increased with increasing initial bone loss. This was less evident in the oldest age group. It was concluded that the progression of bone loss in the present material is consistent with a "burst" theory. However, the progression did not occur randomly with regard to previous loss of alveolar bone and time.     

Model-independent assessment of accumulation kinetics based on moments of drug disposition curves

Summary The bounds of the accumulation profile can be predicted on the basis of the mean disposition residence time (MDRT) of a drug. The time to reach 90% of the plateau level (t _0.9) is less than 3.7 MDRT. This prediction can be improved if, in addition, the variance of disposition residence time (VDRT, CV _D ² =VDRT/MDRT²), or the terminal exponential coefficient (), is known. For CV _D ² 1 or MDRT1, the time to reach steady state (t_0.9) approaches 2.3 MDRT (limiting case of monoexponential drug disposition curve). Conditions are stated under which can be regarded as the principal determinant of the accumulation rate.     

基于项目反应理论的中国职业人群职业紧张测量核心量表条目分析

目的 利用项目反应理论（item response theory,IRT）对《中国版职业紧张核心量表》质量进行分析与评价,为后期量表使用和修订提供参考依据。方法 采用方便抽样方法,抽取湖北省两家三甲医院和多家一、二级医院共1261名医务人员作为研究对象,应用《中国版职业紧张核心量表》调查其职业紧张情况。采用主成分分析验证量表4个维度的单维性。采用IRT中的Same Jima等级反应模型计算每个条目的区分度、难度系数和信息量,从微观角度评价量表的测量特性。结果 量表4个维度均满足单维性假设。IRT结果显示所有条目的区分度较好,取值范围在0.67~3.10;17个条目中有13个条目的难度系数在-2.78~2.30之间,且不存在难度逆反现象,条目9和11难度过高且难度逆反,条目15和16难度过低过高并存且有难度逆反现象,提示待改进;除了条目9、11和15提供的信息量中等,条目16和17提供的信息量较差以外,其余条目的信息量均较好。结论 《中国版职业紧张核心量表》所有条目的区分度较好。从难度系数和信息量两个角度,条目9、11、15、16、17的测验质量均是有待改进的,其余条目性能良好,建议针对上述分析结果结合专家意见对问题条目进行修订。     

基于经典测量理论与项目反应理论的消化性溃疡生命质量测定量表QLICD-PU(V2.0)条目分析

目的 运用经典测量理论与项目反应理论对消化性溃疡患者生命质量量表QLICD-PU(V2.0)的条目进行分析与评价,为量表的改进与完善提供依据。方法 应用QLICD-PU(V2.0)对170例消化性溃疡患者进行测评,采用经典测量理论中的变异度法、相关系数法、因子分析法、克朗巴赫系数法,同时应用项目反应理论中的Samejima等级反应模型计算每个条目的难度、区分度系数和信息量,来评价QLICD-PU(V2.0)量表条目的质量。结果 经典测量理论结果提示QLICD-PU(V2.0)共性模块中变异法计算在总的41个条目中条目标准差小于0.90的有7个; 在总的41个条目中有9个条目与其所在领域的相关性比较低; 项目反应理论结果显示所有条目的区分度较好,取值范围均在1.01～1.69; 在总的41个条目中33个条目的难度系数取值范围在-3.94～3.70,且随着难度等级(B1→B4)的增加呈现出单调递增的趋势; 共性模块条目的平均信息量均较好,特异模块的平均信息量不太理想。结论 QLICD-PU(V2.0)量表所有条目区分度,大部分条目的难度以及共性模块平均信息量比较好,量表具较好的信度,但仍然有部分条目有待进一步修订并验证效果。     

基于共生理论的国家医联体绩效考核指标分析及优化

基于共生理论,从共生单位、共生环境、共生模式和共生界面4个要素入手,分析国家医联体绩效考核指标中存在问题。国家医联体绩效考核指标的横向可比性有待增强,部分指标标准未统一,指标导向性不强。由此总结出加强医联体绩效考核的导向性作用,强化指标的横向可比性,将医联体文化融合的指标纳入医联体绩效考核四项措施。