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991.
The main aim of this paper is to analyze the relationships of involvement in the "botellon" (meetings of youth in public places to drink, chat, etc.) with alcohol/other drug abuse and vandalism in young people. A school survey was performed in centres of Compulsory Secondary School (E.S.O.), high school, professional training and University education in Lugo, NW Spain. The sample (aged 12 to 30) was split into three groups according to alcohol use and botellon involvement; drug abuse, drug-related problems and vandalism were assessed in each group. Results indicate that regular botellon attendants display more problems with alcohol and other drugs, as well as higher involvement in vandalism; this relationship is stronger among young students. The increase in adolescent risk associated with the practice of the botellon is explained by peer group pressure to use drugs and the greater accessibility of alcohol/other drugs in these contexts.  相似文献   
992.
In this study, we analyzed the validity of the conventional 80% power. The minimal sample size and power needed to guarantee non-overlapping (1-alpha)% confidence intervals for population means were calculated. Several simulations indicate that the minimal power for two means (m = 2) to have non-overlapping CIs is .80, for (1-alpha) set to 95%. The minimal power becomes .86 for 99% CIs and .75 for 90% CIs. When multiple means are considered, the required minimal power increases considerably. This increase is even higher when the population means do not increase monotonically. Therefore, the often adopted criterion of a minimal power equal to .80 is not always adequate. Hence, to guarantee that the limits of the CIs do not overlap, most situations require a direct calculation of the minimum number of observations that should enter in a study.  相似文献   
993.
994.
The main purpose of this study is to test if children with cancer receiving chemotherapy show a poorer physical self-concept, less self-esteem and more anxiety and depression than healthy children (with no cancer history) within the same age range (9-16 years old) and social condition. Furthermore, the capacity of self-concept and self-esteem to predict emotional distress is analyzed. The Spanish versions of PSDQ, CDI and STAIC were administered to 30 children with cancer and 90 healthy children. Except for the health and flexibility dimensions in the PSDQ, no significant differences between groups were found. Self-esteem was the best predictor of depression, whereas health and self-concept predicted anxiety.  相似文献   
995.
Using a dual-task methodology, this study examined the involvement of selective attention in spatial localization. Thirty participants located a single, briefly presented, peripheral target stimulus, appearing in one of 50 positions on either side of a central fixation point, with or without the requirement to identify a simultaneously presented central distractor stimulus. Results revealed a robust interference effect in localization performance at short target durations that depended on the number of the to-be-identified distractor items. This outcome provides convergent support for the role of the attentional system in spatial localization.  相似文献   
996.
In two visuospatial working memory (VSWM) span experiments, older and young participants were tested under conditions of either high or low interference, using two different displays: computerized versions of a 3 x 3 matrix or the standard (randomly arrayed) Corsi block task (P. M. Corsi, 1972). Older adults' VSWM estimates were increased in the low-interference, compared with the high-interference, condition, replicating findings with verbal memory span studies. Young adults showed the opposite pattern, and together the findings suggest that typical VSWM span tasks include opposing components (interference and practice) that differentially affect young and older adults.  相似文献   
997.
This study examined the temporal associations of cigarette smoking with prosmoking social influences, academic performance, and delinquency in a cohort of 6,527 adolescents surveyed at ages 13, 16, 18, and 23 years. Prosmoking peer and family influences were risk factors for future smoking throughout adolescence, with family influences perhaps also operating indirectly through the adolescent's exposure to prosmoking peers. There were reciprocal associations of youth smoking with parental approval, peer smoking, and poor grades (but not delinquency), with youth smoking emerging as a stronger antecedent than consequence of these psychosocial factors. Few gender differences in these associations were observed. Implications of these findings for efforts to prevent youth smoking are discussed.  相似文献   
998.
The aim of the present study was to analyze the psychometric characteristics of the Body Image Assessment Software (BIAS), an innovative interactive computer program developed to assess body image disturbances. The program was tested on 252 psychology students at the University of Barcelona and 51 patients with an eating disorder (ED). The subjects filled in the Eating Attitudes Test-26, the Body Shape Questionnaire, the body dissatisfaction scale of the Eating Disorders Inventory-2, and the Body Image Assessment-Revised (a test of silhouettes). Results showed good validity and very high reliability. Furthermore, BIAS was able to discriminate between people who were at risk of an ED and those who were not, as well as between people with and without a history of an ED. Those at risk of having an ED and those with a current ED showed more body image distortion (overestimation of body size) and higher levels of body image dissatisfaction.  相似文献   
999.
This article presents a classification method that makes possible the detection of important decision strategies that people use in nonrisky multiattribute decision tasks. The classification method incorporates a multimethod approach that combines elements of both structural modeling and process tracing. We begin with a discussion of nine common characteristics of decision strategies and then classify 13 decision strategies on the basis of these characteristics. Next, we demonstrate that six of the characteristics can be used to develop one outcome-based and three process-based metrics. In addition, we present an algorithm that shows how to use the metrics. We demonstrate that using our metrics in conjunction with a measure for direction of search allows identification of most of the 13 decision strategies. Finally, we outline the potential of our research for the design of decision support systems such as online shops.  相似文献   
1000.
The purpose of this study was to determine the differences in general health status and quality of life between patients who present “non-normative eating behaviours” (namely, binge eating disorder, night eating syndrome, sweet /fat food cravings and continuous nibbling) and patients without these eating behaviour characteristics. A cohort of 168 women with obesity, all candidates to bariatric surgery, aged between 15 and 65 (M = 39.04; SD = 10.86), with a body mass index ranging between 30.37 and 80.65 (M = 48.79; SD = 8.37), was studied. Participants answered to a clinical interview, to SF-36 and to ORWELL-97, after their informed consent. Results suggest that women with obesity reporting binge eating disorder, night eating syndrome and continuous nibbling show poorer general health status and worst quality of life than those who do not present these “non-normative eating behaviours”. Moreover, the general health status and the quality of life of patients with sweet/fat food cravings do not differ from those who do not report this eating behaviour. Nevertheless, patients reporting the eating behaviours studied do not differ from the others regarding their body mass index.  相似文献   
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