Stability and Change in Type A Components and Cardiovascular Reactivity in Medical Students During Periods of Academic Stress1

This study examined the effects of academic stress upon components of Type A behavior and cardiovascular reactivity. In a longitudinal design, heart rate and blood pressure responses to the Type A Structured Interview (SI) and additional laboratory challenges were measured in medical students at three points during an academic semester. Sessions 1 and 3 were scheduled during vacation periods; Session 2 took place during an intensive examination week. Results indicated that three “stylistic” components of Pattern A derived from the SI—loud and explosive speech, short response latency, and potential for hostility—increased significantly during the exam period. Similar increases achieved marginal significance for another stylistic component, rapid and accelerated speech. By contrast, global Type A assessments did not increase with academic demands. Cardiovascular reactivity was significantly but only moderately stable across the three sessions, showing less consistency than has been reported in previous research. In addition, there was little evidence in this study that cardiovascular reactivity was potentiated by academic stress or by Type A behavior. These results demonstrate the influence of naturalistic environmental factors on overt behavioral components that have recently been suggested as coronary risk factors. Therefore, it is advisable for future experimental and epidemiological research to examine the social and environmental context in which these behaviors occur.     

A general linear model for estimating effect size in the presence of publication bias

When the process of publication favors studies with smallp-values, and hence large effect estimates, combined estimates from many studies may be biased. This paper describes a model for estimation of effect size when there is selection based on one-tailedp-values. The model employs the method of maximum likelihood in the context of a mixed (fixed and random) effects general linear model for effect sizes. It offers a test for the presence of publication bias, and corrected estimates of the parameters of the linear model for effect magnitude. The model is illustrated using a well-known data set on the benefits of psychotherapy.Authors' note: The contributions of the authors are considered equal, and the order of authorship was chosen to be reverse-alphabetical.     

Stimulus generalization and the peak shift with movement stimuli

Stimulus generalization is suggested as an alternative method for examination of the "novelty" problem in motor learning. These experiments demonstrated that stimulus generalization occurs using simple movements as stimuli. The phenomenon of the "peak shift" in post-discrimination generalization gradients was also examined. The first experiment demonstrated that a peak shift occurred using linear movements as stimuli and that the magnitude of the peak shift increased as the difference between the training stimuli decreased. The second experiment showed similar results when the stimuli consisted of a range of movements rather than single movement length. The final experiment provided evidence that perception of movement length is influenced by the magnitude of an immediately preceding movement. The relevance of these studies to current motor-learning theory is discussed.     

Categories and particulars: prototype effects in estimating spatial location

A model of category effects on reports from memory is presented. The model holds that stimuli are represented at 2 levels of detail: a fine-grain value and a category. When memory is inexact but people must report an exact value, they use estimation processes that combine the remembered stimulus value with category information. The proposed estimation processes include truncation at category boundaries and weighting with a central (prototypic) category value. These processes introduce bias in reporting even when memory is unbiased, but nevertheless may improve overall accuracy (by decreasing the variability of reports). Four experiments are presented in which people report the location of a dot in a circle. Subjects spontaneously impose horizontal and vertical boundaries that divide the circle into quadrants. They misplace dots toward a central (prototypic) location in each quadrant, as predicted by the model. The proposed model has broad implications; notably, it has the potential to explain biases of the sort described in psychophysics (contraction bias and the bias captured by Weber's law) as well as symmetries in similarity judgments, without positing distorted representations of physical scales.     

The power of statistical tests in meta-analysis

Calculations of the power of statistical tests are important in planning research studies (including meta-analyses) and in interpreting situations in which a result has not proven to be statistically significant. The authors describe procedures to compute statistical power of fixed- and random-effects tests of the mean effect size, tests for heterogeneity (or variation) of effect size parameters across studies, and tests for contrasts among effect sizes of different studies. Examples are given using 2 published meta-analyses. The examples illustrate that statistical power is not always high in meta-analysis.     

传统药物治疗认识误区几点浅析

药物是治疗疾病的物质基础,传统药物治疗认识中的许多误区影响人们对疾病的合理治疗.积极宣传药物治疗新理念,普及现代药学知识和理论,提高广大人民群众对药物治疗的认识水平,是避免出现药物治疗认识误区的主要手段.应加强宣传力度,带领群众走出误区,促进合理用药.     

药物治疗的风险及其处理

造成药物治疗风险的因素包括药物因素、病情因素、患者因素、用药因素及管理因素等。通过对药物进行严格监管,对医药从业人员加强培训和教育,对民众开展科普教学和用药指导,可以降低药物治疗的风险。风险事件主要表现为用药差错、药物不良反应或药物治疗无效。在药物治疗中,首先必须时刻警惕和及时发现风险;其次需要全面评估风险,还要对疾病风险和药物治疗风险进行比较。应尽可能避免药物治疗的风险,对于必须承受的风险,需采取相应措施,减少风险事件发生的概率和严重程度。如果存在较大风险,务必同时设计处理风险事件的预案,并与患者及其家属保持良好的交流和沟通。     

Sources of variability in children’s language growth

The present longitudinal study examines the role of caregiver speech in language development, especially syntactic development, using 47 parent–child pairs of diverse SES background from 14 to 46 months. We assess the diversity (variety) of words and syntactic structures produced by caregivers and children. We use lagged correlations to examine language growth and its relation to caregiver speech. Results show substantial individual differences among children, and indicate that diversity of earlier caregiver speech significantly predicts corresponding diversity in later child speech. For vocabulary, earlier child speech also predicts later caregiver speech, suggesting mutual influence. However, for syntax, earlier child speech does not significantly predict later caregiver speech, suggesting a causal flow from caregiver to child. Finally, demographic factors, notably SES, are related to language growth, and are, at least partially, mediated by differences in caregiver speech, showing the pervasive influence of caregiver speech on language growth.     

论病历所有权归属与所有权行使

在现行法律框架下,通过文献检索、走访调研以及比较法研究方法探讨我国病历的所有权归属与所有权行使问题.本文认为病历具有物的属性,这是本文展开探讨的前提.基于对患者与医疗机构之间的空白病历买卖合同关系、医疗服务合同关系、医疗机构与医务人员之间的雇佣关系等多重法律关系的分析以及出于对患者隐私权等权利保护的考虑,认为病历所有权应归属于患者.同时,在病历私有说的基础上,分析了病历所有权行使、病历所有权的限制以及病历所有权受侵害时的救济等问题.     

女性盆腔脏器脱垂的传统手术治疗

对于女性盆腔脏器脱垂的手术治疗,传统的手术方式包括阴道封闭术、曼氏手术和阴式全子宫切除术.阴道封闭术操作相对简单,适用于无性生活要求的、合并症较多的年老体弱者,但术后可能存在新发压力性尿失禁,并且导致性功能障碍,术中是否切除子宫尚有争议.曼氏手术保留子宫、操作简单,但术后脱垂复发及妊娠后宫颈机能不全问题仍有待研究.阴式全子宫切除术对于POP-Q评分II期及以内的脱垂患者,治疗效果最佳,期别高的患者术后复发仍可使用保守或再次手术治疗补救,本手术方式术后较少出现性交痛.总而言之,选择适当的适应证并积极与患者沟通后,女性盆腔脏器脱垂的传统手术治疗仍为不错的治疗方式.