能容纳二次应力的J积分断裂参量

在阐述Ｊ积分物理意义的基础上，通过有限元的计算，对多种能用于二次应力情况下的修正Ｊ积分进行了评价，讨论了它们间的相互关系及其适用范围，证明了由Ｂｌａｃｋｂｕｒ提出的Ｊ＾ｎｗ的物理意义最为明确，可作为一种断裂参量。     

Lack of generalizability of sensitivity and specificity with treatment effects

In biomarker development, two types of summary measures are often used to describe marker accuracy. Positive and negative predictive values describe how well a marker predicts clinical states of interest, while sensitivity and specificity describe how well a marker discriminates between the two states. Insofar as predictive values depend heavily on the prevalence of the clinical states and sensitivity and specificity may not, sensitivity and specificity are preferred in early biomarker development.In many applications, an ideal property of a biomarker is fulfillment of the first Prentice criterion. Under this condition, predictive values do not depend on a covariate (such as treatment) because the biomarker captures all relevant information about the clinical state of interest. A similar condition can be defined for sensitivity and specificity which states that these measures do not depend on a covariate (e.g. treatment). This condition, which we refer to as the equal discriminatory accuracy (EDA) condition, is desirable because it allows sensitivity and specificity from one treatment setting (or covariate value) to be applied to a different setting. We demonstrate, however, that the Prentice condition and EDA are incompatible. Further, under a simple proportional hazards model for a time-to-event outcome, EDA will not be satisfied. We present numerical examples as well as examples of a potential marker in late-stage prostate cancer and another for cervical cancer screening. These results demonstrate that evaluating sensitivity and specificity within treatment (or other covariate) groups is necessary even when simple proportional hazards models or the Prentice criterion holds.     

The impact of a misspecified random-effects distribution on the estimation and the performance of inferential procedures in generalized linear mixed models

Estimation in generalized linear mixed models (GLMMs) is often based on maximum likelihood theory, assuming that the underlying probability model is correctly specified. However, the validity of this assumption is sometimes difficult to verify. In this paper we study, through simulations, the impact of misspecifying the random-effects distribution on the estimation and hypothesis testing in GLMMs. It is shown that the maximum likelihood estimators are inconsistent in the presence of misspecification. The bias induced in the mean-structure parameters is generally small, as far as the variability of the underlying random-effects distribution is small as well. However, the estimates of this variability are always severely biased. Given that the variance components are the only tool to study the variability of the true distribution, it is difficult to assess whether problems in the estimation of the mean structure occur. The type I error rate and the power of the commonly used inferential procedures are also severely affected. The situation is aggravated if more than one random effect is included in the model. Further, we propose to deal with possible misspecification by way of sensitivity analysis, considering several random-effects distributions. All the results are illustrated using data from a clinical trial in schizophrenia.     

Implementing a system of quality-of-life diagnosis and therapy for breast cancer patients: results of an exploratory trial as a prerequisite for a subsequent RCT

A system for quality-of-life diagnosis and therapy (QoL system) was implemented for breast cancer patients. The system fulfilled the criteria for complex interventions (Medical Research Council). Following theory and modeling, this study contains the exploratory trial as a next step before the randomised clinical trial (RCT) answering three questions: (1) Are there differences between implementation sample and general population? (2) Which amount and type of disagreement exist between patient and coordinating practitioners (CPs) in assessed global QoL? (3) Are there empirical reasons for a cutoff of 50 points discriminating between healthy and diseased QoL? Implementation was successful: 74% of CPs worked along the care pathway. However, CPs showed preferences for selecting patients with lower age and UICC prognostic staging. Patients and CPs disagreed considerably in values of global QoL, despite education in QoL assessment by outreach visits, opinion leaders and CME: Zero values of QoL were only expressed by patients. Finally, the cutoff of 50 points was supported by the relationship between QoL in single items and global QoL: no patients with values above 50 dropped global QoL below 50, but values below 50 and especially at 0 points in single items, induced a dramatic fall of global QoL down to below 50. The exploratory trial was important for defining the complex intervention in the definitive RCT: control for age and prognostic stage grading, support for a QoL unit combining patient''s and CP''s assessment of QoL and support for the 50-point cutoff criterion between healthy and diseased QoL.     

Evaluation of a data-base

The records of 421 psychiatric patients were analysed by a consistent method, allowing an optimal use of indicant-patterns. It was assumed that such a procedure would give a satisfactory predictive capacity, even for operational criteria as for example choice of treatment, duration of stay in hospital, or a global evaluation of outcome. The study demonstrates, however, that fundamental changes in the data-base are necessary. Problems of reliability, validity, sensitivity and specificity are discussed and some suggestions are offered for the future improvement of psychiatric data-bases.     

人工繁育恒河猴婴猴生长发育指标的测定分析

目的建立人工繁殖恒河猴婴猴生长发育指标的标准数据库。方法随机对90只人工饲养繁殖的恒河猴(从100 d至1周岁)进行体重、身长、尾长、前肢长、后肢长发育指标测定。结果测定后的数据,经统计学分析和绘制生长曲线图,发现人工饲养条件下的恒河猴(1周岁前),其生长发育指标基本均匀一致,只有个别出现发育迟缓或发育不良现象。随时间推移,雄性生长速度要快于雌性。结论所建立的恒河猴婴猴正常生长发育生理指标,为提高人工饲养繁育恒河猴技术和不断改善恒河猴营养与发育健康提供了科学数据。     

儿童单纯性肥胖的诊断和治疗

关于肥胖的诊断国内外并尚无统一的判断标准，WHO认为10岁以下和10岁以上应有不同的评价标准，推荐10岁以下儿童使用身高别体质量，10～24岁采用体质量指数（BMI），国际肥胖问题工作组织（IOTF）认为BMI适宜用来判断儿童青少年超重和肥胖。WHO和IOTF提出的18岁BMI超重、肥胖标准完全一样，分别为25和30kg／m^2，而中国肥胖问题工作组（WGOC）制定的标准较比前二者低，18岁BMI超重和肥胖界值点分别为24和28kg／m^2。儿童肥胖的治疗不同于成人，成人期可使用的手术去脂、药物减肥、饥饿疗法、禁食等，在儿童时期均不宜使用。目前国内外公认儿童肥胖治疗方法包括行为矫正、饮食调整和运动等综合治疗方案。     

药品监督行政执法办案质量评价标准探析

研究和确立药品监督行政执法办案质量评价标准有其积极的现实意义.本文分析了评价的基本标准:执法主体合法、认定事实清楚、证据确凿无疑、适用依据正确、遵循法定程序、符合立法目的.这六项标准构成评价的否决项,执法人员必须谨记.     

新型农村合作医疗建立及对农村居民健康保障研究

合作医疗已成为上海农村的基本医疗保险制度。调查表明，合作医疗制度覆盖人群广，参保人群门诊就医及“小病”的就医基本得到保障。文章提出，建立新型合作医疗制度，政府必须制订刚性的政策，提高基金的缴费标准，加强对定点医院及就医者的管理，并建立区、市住院基金统筹制度，提高合作医疗基金的社会化、信息化的管理水平，提高合作医疗的保障水平。     

小鼠四诊采集项目标准的建议

辨证论治机理实验研究主要采用的是小鼠.通过我们长期的研究和观察,初步建立了小鼠四诊采集项目标准.该标准主要有四部分内容:(1)类似于问诊采集的内容,包括一般情况、始病和治疗经过、饮食情况、脏腑病位;(2)闻诊采集的内容;(3)望诊采集的内容,包括自然望诊、胖瘦、小鼠旷场自主活动计数、爪和尾显微拍照后计算机图像处理等内容,涉及类似望形体状况、望形体虚实、望形体神、望形体寒热、望运动步态、望精力、望毛色虚实、望呼吸状况、望眼神、望耳、望鼻、望唇、望腹、望二阴、望大便、望小便、望爪、望尾、望睡眠、爪和尾显微观察等;(4)切诊采集的内容,包括体温、肿块检测、脉的至数与节律、肤之温凉、肌力等.同时,还对是否可以实现小鼠的四诊以及如何开展四诊进行了理论分析.