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781.
Sequential multiple assignment randomized trials (SMARTs) are a useful and increasingly popular approach for gathering information to inform the construction of adaptive interventions to treat psychological and behavioral health conditions. Until recently, analysis methods for data from SMART designs considered only a single measurement of the outcome of interest when comparing the efficacy of adaptive interventions. Lu et al. proposed a method for considering repeated outcome measurements to incorporate information about the longitudinal trajectory of change. While their proposed method can be applied to many kinds of outcome variables, they focused mainly on linear models for normally distributed outcomes. Practical guidelines and extensions are required to implement this methodology with other types of repeated outcome measures common in behavioral research. In this article, we discuss implementation of this method with repeated binary outcomes. We explain how to compare adaptive interventions in terms of various summaries of repeated binary outcome measures, including average outcome (area under the curve) and delayed effects. The method is illustrated using an empirical example from a SMART study to develop an adaptive intervention for engaging alcohol- and cocaine-dependent patients in treatment. Monte Carlo simulations are provided to demonstrate the good performance of the proposed technique.  相似文献   
782.
Many researchers face the problem of missing data in longitudinal research. Especially, high risk samples are characterized by missing data which can complicate analyses and the interpretation of results. In the current study, our aim was to find the most optimal and best method to deal with the missing data in a specific study with many missing data on the outcome variable. Therefore, different techniques to handle missing data were evaluated, and a solution to efficiently handle substantial amounts of missing data was provided. A simulation study was conducted to determine the most optimal method to deal with the missing data. Results revealed that multiple imputation (MI) using predictive mean matching was the most optimal method with respect to lowest bias and the smallest confidence interval (CI) while maintaining power. Listwise deletion and last observation carried backward also scored acceptable with respect to bias; however, CIs were much larger and sample size almost halved using these methods. Longitudinal research in high risk samples could benefit from using MI in future research to handle missing data. The paper ends with a checklist for handling missing data.  相似文献   
783.
Summary

This article presents an overview of the history of efforts to protect human subjects in research. It discusses the establishment of international, national, organizational, and institutional procedures designed to protect human participants. The article provides a detailed summary of the principal ethical codes for research and their origins. It includes discussions of the most frequently encountered ethical issues ranging from the initial decision to undertake the project, through the selection and application of the various research procedures, to the analysis and interpretation of the data.  相似文献   
784.
This research explores the role of three intercultural personality traits—emotional stability, social initiative, and open-mindedness—as coping resources for expatriate couples’ adjustment. First, we examined the direct relationships of expatriates’ and expatriate spouses’ personality trait levels with psychological and sociocultural adjustment. Psychological adjustment refers to internal psychological outcomes such as mental health and personal satisfaction, whereas sociocultural adjustment refers to more externally oriented psychological outcomes that link the individual to the new environment. Second, we examined the association of expatriates’ personality trait levels with professional adjustment, which was defined in terms of job performance and organizational commitment. Cross-sectional analyses among 196 expatriates and expatriate spouses (i.e., 98 expatriate couples) revealed that the three dimensions are each associated with specific facets of adjustment. A longitudinal analysis among a subsample (45 couples) partially confirmed these findings. Furthermore, we obtained evidence for a resource compensation effect, that is, the compensatory process whereby one partner's lack of sufficiently high levels of a certain personality trait is compensated for by the other partner's high(er) levels of this traits. Through this resource compensation effect, the negative consequences of a lack of sufficient levels of a personality trait on adjustment can be diminished. Apparently, in the absence of sufficiently high trait levels, individuals can benefit from personality resources in their partners.  相似文献   
785.
ABSTRACT

This study presents Danish data for the Symbol Digit Modalities Test (SDMT), Color Trails Test (CTT), and a modified Stroop test from 100 subjects aged 60–87 years. Among the included demographic variables, age had the highest impact on test performances. Thus, the study presents separate data for different age groups. For SDMT and CTT1, Danish Adult Reading Test (DART) score also had a significant impact on test performances. The incongruent version of the modified Stroop test was significantly correlated to education. Moderate and significant correlations were found between the three tests. Even though the three tests are commonly used, few normative data for elderly exists. SDMT and CTT performances from this study were in the same range as previously published international norms, but the validity of the result from the modified Stroop test could not be investigated.  相似文献   
786.
The Fuld Object Memory Evaluation (FOME) has considerable utility for cognitive assessment in older adults, but there are few normative data, particularly for the oldest old. In this study, 80 octogenarians and 244 centenarians from the Georgia Centenarian Study completed the FOME. Total and trial-to-trial performance on the storage, retrieval, repeated retrieval, and ineffective reminder indices were assessed. Additional data stratified by age group, education, and cognitive impairment are provided in the Supplemental data. Octogenarians performed significantly better than centenarians on all FOME measures. Neither age group benefitted from additional learning trials beyond Trial 3 for storage and Trial 2 for retention and retrieval. Ineffective reminders showed no change across learning trials for octogenarians, while centenarians improved only between Trials 1 and 2. This minimal improvement past Trial 2 indicates that older adults might benefit from a truncated version of the test that does not include trials three through five, with the added benefit of reducing testing burden in this population.  相似文献   
787.
788.
The rate of discounting future goods is a crucial factor in intertemporal trade-offs, upon which depends not only individual well-being but also that of our planet: How much privation now for a temperate future for our grandchildren? What is the best way to measure how the value of future goods decreases with its delay? The most accurate discount functions involve several covarying parameters, making interpretation equivocal. A universal and robust measure is the area under the discount curve, the AuC. The AuC of a hyperbolic discount function is a logarithmic function of the discount rate, k. The same integral also approximates the area under a hyperboloid function. A simple technique converts each datum into estimates of the discount rate, eliminating rogue data points in the process. These trimmed estimates are converted into areas and tested against data, where they succeed at predicting the AuC and its relation to log(k).  相似文献   
789.
Research has suggested that perfectionism, agreeableness, and neuroticism may influence relationship adjustment; however, these personality variables have not been examined in conjunction when considering relationship adjustment. In a sample of 222 university students (95 male, 126 female), the perfectionism dimensions of concern over mistakes and parental criticism were found to be significantly negatively related to dyadic adjustment. Agreeableness and neuroticism were also significantly negatively related to dyadic adjustment, and accounted for significant variance in explaining dyadic adjustment, while perfectionism dimensions did not. The results suggest that while negative aspects of perfectionism, such as concern over mistakes, have an impact on dyadic adjustment, the personality variables of agreeableness and neuroticism have a more salient impact. The implications of these findings for research in interventions for perfectionism and relationship adjustment are discussed.  相似文献   
790.
Chinese people have held collectivistic values such as obligation, giving to other people, obedience and sacrifice of personal interests for thousands of years. In recent decades, China has undergone rapid economic development and urbanisation. This study investigates changing cultural values in China from 1970 to 2008 and the relationship of changing values to ecological shifts. The conceptual framework for the study was Greenfield's (2009) theory of social change and human development. Changing frequencies of contrasting Chinese words indexing individualistic or collectivistic values show that values shift along with ecological changes (urbanisation, economic development and enrollment in higher education), thereby adapting to current sociodemographic contexts. Words indexing adaptive individualistic values increased in frequency between 1970 and 2008. In contrast, words indexing less adaptive collectivistic values either decreased in frequency in this same period of time or else rose more slowly than words indexing contrasting individualistic values.  相似文献   
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