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901.
Aims. This study investigated the effect of simulated visual impairment on the speed and accuracy of performance on a series of commonly used cognitive tests. Methods. Cognitive performance was assessed for 30 young, visually normal subjects (M=22.0±3.1 years) using the Digit Symbol Substitution Test (DSST), Trail Making Test (TMT) A and B and the Stroop Colour Word Test under three visual conditions: normal vision and two levels of visually degrading filters (VistechTM) administered in a random order. Distance visual acuity and contrast sensitivity were also assessed for each filter condition. Results. The visual filters, which degraded contrast sensitivity to a greater extent than visual acuity, significantly increased the time to complete (p<.05), but not the number of errors made, on the DSST and the TMT A and B and affected only some components of the Stroop test. Conclusions. Reduced contrast sensitivity had a marked effect on the speed but not the accuracy of performance on commonly used cognitive tests, even in young individuals; the implications of these findings are discussed.  相似文献   
902.
ABSTRACT Although the role of emotional processing is central to contemporary models of risky decision making, to date the role of trait emotional understanding has not been explored experimentally in this context. The current experiment ( N =326) explores the role of alexithymia with respect to performance on the standard Iowa Gambling Task (IGT) and a version where cumulative financial feedback is obscured. Standard learning on the IGT was observed for those low in alexithymia. Those high in alexithymia learned to avoid disadvantageous decks over the first half of the task. However, over the later trials they showed a change in performance, shifting from advantageous to disadvantageous and back to advantageous decks again (termed an "explore-learn-change-return" strategy). It is argued that this is due to an inability to fully consolidate earlier learning and reduced sensitivity to losses. The absence of cumulative feedback independently resulted in reduced performance.  相似文献   
903.
Few studies examine whether and how parental attitudes towards genetic testing change over time. In this study we interviewed parents of 14 children with newly identified hearing loss at two time points: after referral to genetics and 1 year later. Qualitative analyses of parental narratives indicate that parental attitudes did not change significantly over this time. Parents who perceived genetic testing to be useful continued to value it after testing, while parents who did not perceive it as being useful for their child’s future held the same view a year later. The only parents who changed their views regarding the usefulness of genetic testing for hearing loss were those who reported that their children underwent significant changes in their hearing loss or were faced with other life threatening conditions. Parents were also often unaware of the role of the genetic counselor and how genetic counseling could help address many of their lingering questions and concerns. These emergent themes indicate the need for geneticists and genetic counselors to be aware of and sensitized to the questions and attitudes that bring parents to a genetic evaluation, as well as the reasons why parents may not follow up with genetic testing for hearing loss when recommended.  相似文献   
904.
The ideal elf: identity exploration in World of Warcraft.   总被引:1,自引:0,他引:1  
In this study, we examine the identity exploration possibilities presented by online multiplayer games in which players use graphics tools and character-creation software to construct an avatar, or character. We predicted World of Warcraft players would create their main character more similar to their ideal self than the players themselves were. Our results support this idea; a sample of players rated their character as having more favorable attributes that were more favorable than their own self-rated attributes. This trend was stronger among those with lower psychological well-being, who rated themselves comparatively lower than they rated their character. Our results suggest that the game world allows players the freedom to create successful virtual selves regardless of the constraints of their actual situation.  相似文献   
905.
Traffic research shares a fundamental dilemma with other areas of empirical research in which humans are potentially put at risk. Research is justified because it can improve safety in the long run. Nevertheless, people can be harmed in the research situation. Hence, we need to balance short-term risks against long-term safety improvements, much as in other areas of research with human subjects. In this paper we focus on ethical issues that arise when human beings are directly affected in the performance of research by examining how the ethical requirements in biomedical research can inform traffic research. After introducing the basic ethical requirements on biomedical research, each of the major requirements is discussed in relation to traffic research. We identify the main areas where biomedical research and traffic research differ, and where the ethical requirements from the former cannot easily be transferred to the latter. Finally, we argue that there is a need for systematic studies of the ethics of traffic research and point to some of the issues that need to be addressed.  相似文献   
906.
Young and older adults' ability to retrieve the spellings of high- and low-frequency words was assessed via tests of spelling recognition and production. One of the spelling production tests required participants to write down the correct spellings of auditorily presented words, and accuracy was used to categorize participants in both age groups as good or poor spellers. The results showed that individual spelling ability and word frequency contributed to age differences. Older adults who were poor spellers were less accurate in recognizing and producing correct spelling than young adults who were poor spellers. In contrast, no age differences occurred for good spellers. Furthermore, low-frequency words were especially difficult for young adults and poor spellers, relative to older adults and good spellers. These results indicate that aging alone is not detrimental to the processes underlying recognition or production of spelling but instead compounds existing problems caused by poor spelling.  相似文献   
907.
Examined the age of onset of ADHD symptoms and subtypes using parent ratings of a large sample of elementary school students. Results showed: (1) in children with ADHD-combined type, hyperactive-impulsive symptoms emerged at younger ages than inattention symptoms; (2) about one-fifth of children who met symptom count and impairment criteria for ADHD did not meet the age of onset criterion; (3) Children who did not meet the age of onset criterion consisted primarily of children with inattention problems; and (4) children who did not meet the age of onset criterion had more impaired parent-child relationships, self-esteem, family functioning, and higher overall impairment ratings than children who did meet the criterion. These results raise questions about the validity of the age of onset criterion for ADHD as formulated in DSM-IV.  相似文献   
908.
This study focused on gaining a better understanding of the neuropsychological abilities of preschool-aged children who show elevated levels of hyperactivity and oppositional-defiance. It examined the performance of children aged 48 to 67 months on tests of attention/executive function, language, memory, and sensorimotor abilities, as measured by the NEPSY and Conners' K-CPT. Two hundred thirty-seven children were divided into four subgroups based on mothers' report of behavior using rating scales and a diagnostic interview: hyperactive only (HYP), oppositional-defiant only (OD), hyperactive and oppositional-defiant (HYP/OD), and nonproblem. Children in the HYP/OD group scored significantly worse than nonproblem children on four of nine subtests on the NEPSY, including one test of executive function, one test of language comprehension, and both tests of short-term verbal memory. However, only the test of executive function (Statue) showed significant predictive power, and, while specificity of this subtest was good, sensitivity was poor. On the K-CPT, a continuous performance test, children in both the HYP and HYP/OD groups performed worse than children in the OD and nonproblem groups. When the NEPSY Statue subtest and the K-CPT were used together, overall predictive power was .74. Results suggest that neuropsychological deficits can be observed among preschool children with hyperactivity, particularly when comorbid oppositional-defiance is present; however, moderate predictive power suggests that these tests should be used in conjunction with other methods of assessment.  相似文献   
909.
Animal and human data suggest the existence of a cross-species system of analog number representation (e.g., Cordes, Gelman, Gallistel, & Whalen, 2001; Meeck & Church, 1983), which may mediate the computation of statistical regularities in the environment (Gallistel, Gelman, & Cordes, 2006). However, evidence of arithmetic manipulation of these nonverbal magnitude representations is sparse and lacking in depth. This study uses the analysis of variability as a tool for understanding properties of these combinatorial processes. Human subjects participated in tasks requiring responses dependent upon the addition, subtraction, or reproduction of nonverbal counts. Variance analyses revealed that the magnitude of both inputs and answer contributed to the variability in the arithmetic responses, with operand variability dominating. Other contributing factors to the observed variability and implications for logarithmic versus scalar models of magnitude representation are discussed in light of these results.  相似文献   
910.
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