首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   6131篇
  免费   301篇
  国内免费   2篇
  2023年   51篇
  2022年   48篇
  2021年   81篇
  2020年   123篇
  2019年   155篇
  2018年   199篇
  2017年   217篇
  2016年   298篇
  2015年   140篇
  2014年   178篇
  2013年   693篇
  2012年   330篇
  2011年   360篇
  2010年   213篇
  2009年   196篇
  2008年   299篇
  2007年   268篇
  2006年   251篇
  2005年   194篇
  2004年   214篇
  2003年   206篇
  2002年   164篇
  2001年   111篇
  2000年   95篇
  1999年   78篇
  1998年   67篇
  1997年   66篇
  1996年   72篇
  1995年   79篇
  1994年   65篇
  1993年   51篇
  1992年   55篇
  1991年   51篇
  1990年   48篇
  1989年   34篇
  1988年   46篇
  1987年   34篇
  1986年   25篇
  1985年   47篇
  1984年   42篇
  1983年   33篇
  1982年   50篇
  1981年   30篇
  1980年   25篇
  1979年   42篇
  1978年   24篇
  1977年   35篇
  1975年   27篇
  1974年   34篇
  1970年   20篇
排序方式: 共有6434条查询结果,搜索用时 0 毫秒
981.
This study investigated whether the age-related positivity effect strengthens specific event details in autobiographical memory. Participants retrieved past events or imagined future events in response to neutral or emotional cue words. Older adults rated each kind of event more positively than younger adults, demonstrating an age-related positivity effect. We next administered a source memory test. Participants were given the same cue words and tried to retrieve the previously generated event and its source (past or future). Accuracy on this source test should depend on the recollection of specific details about the earlier generated events, providing a more objective measure of those details than subjective ratings. We found that source accuracy was greater for positive than negative future events in both age groups, suggesting that positive future events were more detailed. In contrast, valence did not affect source accuracy for past events in either age group, suggesting that positive and negative past events were equally detailed. Although ageing can bias people to focus on positive aspects of experience, this bias does not appear to strengthen the availability of details for positive relative to negative past events.  相似文献   
982.
983.
Research among African-Americans indicates this population perceives sickle cell (SCD) to be a serious disease and sickle cell trait (SCT) screening an important intervention. However, studies have consistently demonstrated a lower than desired uptake of SCD education, inadequate knowledge regarding personal and family trait status, and a low perceived susceptibility of giving birth to a child with the disease. We examined general attitudes and beliefs regarding genetics and genetic testing including prenatal testing and newborn screening; we used this information as the foundation to more specifically assess attitudes and beliefs regarding SCD and perceived barriers to SCD education and awareness. Thirty-five African-American adult men and women participated in one of four focus groups. Thematic analysis identified that both prenatal testing and newborn screening are acceptable forms of genetic testing. Based largely on their personal experiences, participants possessed an understanding of the natural progression of SCD but had a limited understanding of the inheritance and probable risk of giving birth to a child with the disease. Barriers to education and greater awareness of SCD were classified as personal, familial, and societal. Community based interventions focused on sharing the stories of individuals with first-hand experiences with SCD should be considered.  相似文献   
984.
The purpose of this phenomenological study was to understand the perceptions of adult male substance offenders who experienced sand tray therapy as an adjunct to their cognitive behavioral rehabilitative treatment. Results indicate a positive experience for participants. Implications for counselors are discussed.  相似文献   
985.
Serial-position curves for targets in short-term recognition memory show modest primacy and marked recency. To construct serial-position curves for lures, we tested orthographic neighbours of study words and assigned each lure to the position of its studied neighbour. The curve for lures was parallel to that for targets. In Experiment 2, only half the lures were neighbours of study words; the other half overlapped a study word by a single letter. The serial-position curve for neighbours of study items was now flatter than the curve for targets. The results are inconsistent with theories in which any factor that benefits targets must hinder lures. Instead, they demand a decision mechanism that assigns a role to item-specific information, as well as to general familiarity information, such as dual-process theory.  相似文献   
986.
We evaluated various forms of hippocampus-dependent learning and memory, and hippocampal synaptic plasticity in THY-Tau22 transgenic mice, a murine tauopathy model that expresses double-mutated 4-repeat human tau, and shows neuropathological tau hyperphosphorylation and aggregation throughout the brain. Focussing on hippocampus, immunohistochemical studies in aged THY-Tau22 mice revealed prominent hyper- and abnormal phosphorylation of tau in CA1 region, and an increase in glial fibrillary acidic protein (GFAP) in hippocampus, but without signs of neuronal loss. These mice displayed spatial, social, and contextual learning and memory defects that could not be reduced to subtle neuromotor disability. The behavioral defects coincided with changes in hippocampal synaptic functioning and plasticity as measured in paired-pulse and novel long-term depression protocols. These results indicate that hippocampal tauopathy without neuronal cell loss can impair neural and behavioral plasticity, and further show that transgenic mice, such as the THY-Tau22 strain, might be useful for preclinical research on tauopathy pathogenesis and possible treatment.  相似文献   
987.
Profile data abound in a broad range of research settings. Often it is of considerable theoretical importance to address specific structural questions with regard to the major pattern as included in such data. A key challenge in this regard pertains to identifying which type of interaction (double ordinal, mixed ordinal/disordinal, double disordinal) most adequately fits the major pattern in a profile data set at hand. In the present article a novel methodology is proposed to deal with this challenge. This methodology is based on constrained and unconstrained versions of a recently introduced 2-mode clustering model, the real-valued hierarchical classes model. The methodology is illustrated using empirical Person × Situation profile data on altruism.  相似文献   
988.
Although infants display preferences for social stimuli early in their lives, we know relatively little about the mechanisms of infant learning about the social world. In the current set of studies, 1-month-old infants underwent an adapted eyeblink conditioning paradigm to examine learning to both 'social' and non-social cues. While infants were asleep, they were presented with either a 'social' stimulus (a female voice) or one of two non-social stimuli (tone or backward voice) followed by an airpuff presented to the eyelid. Infants in the experimental groups displayed increased learning across trials, regardless of stimulus type. However, infants conditioned to the 'social' stimulus showed increased learning compared to infants conditioned to either of the non-social stimuli. These results suggest a mechanism by which learning about the social world occurs early in life and the power of ecologically valid cues in facilitating that learning.  相似文献   
989.
This study examines the relationship between stereotype threat and individual test-taking behaviors. Previous research has examined the impact of stereotype threat on test scores, but little research has examined the impact of stereotype threat on the test-taking behaviors impacting those scores. Using a pre-post experimental design, stereotype threat was manipulated and test-taking behaviors (e.g., time spent per item, response changes) were measured while completing verbal ability items before and after the manipulation. The results indicated that stereotype threat minimally impacted time-related test-taking behaviors, but did impact behaviors related to response changes. Implications of the findings are discussed.  相似文献   
990.
Prospective memory (PM) among older adults has been shown to be influenced by frontal lobe (FL) function. An implementation intention (e.g., 'if situation X occurs, I will do Y') is a mnemonic strategy that may be particularly beneficial for individuals with low-FL function, as it has been suggested that implementation intentions produce heightened accessibility to environmental cues, and automatic triggering of previously formed intentions. The present study investigated the effectiveness of implementation intentions among 32 older adults characterized as possessing high- or low-FL function. Participants were placed into one of two conditions: Read-Only or Implementation Intentions, before being tested on a laboratory prospective memory task. Results indicated that older adults with high-FL composite scores demonstrated better PM than those with low-FL scores, and that those who made implementation intentions outperformed those who simply read task instructions. Of particular interest is the finding that high-FL participants benefited from implementation intentions, suggesting that implementation intentions may improve PM of all older adults regardless of FL function. Theoretical underpinnings of implementation intentions are discussed in the context of FL function.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号