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   2364篇
  免费   62篇
  国内免费   2篇
  2428篇
  2022年   12篇
  2021年   17篇
  2020年   37篇
  2019年   42篇
  2018年   36篇
  2017年   65篇
  2016年   59篇
  2015年   44篇
  2014年   65篇
  2013年   214篇
  2012年   86篇
  2011年   91篇
  2010年   67篇
  2009年   52篇
  2008年   85篇
  2007年   95篇
  2006年   96篇
  2005年   91篇
  2004年   95篇
  2003年   88篇
  2002年   65篇
  2001年   44篇
  2000年   40篇
  1999年   50篇
  1998年   44篇
  1997年   29篇
  1996年   25篇
  1995年   28篇
  1994年   30篇
  1993年   28篇
  1992年   30篇
  1991年   21篇
  1990年   24篇
  1989年   16篇
  1988年   26篇
  1987年   26篇
  1986年   24篇
  1985年   34篇
  1984年   42篇
  1983年   33篇
  1982年   38篇
  1981年   41篇
  1980年   26篇
  1979年   35篇
  1978年   30篇
  1977年   22篇
  1976年   26篇
  1975年   16篇
  1974年   22篇
  1973年   17篇
排序方式: 共有2428条查询结果,搜索用时 31 毫秒
91.
Three experiments examined integral and separable dimensions as attentional selective cues from iconic memory. Sperling's partial-report task was employed with physically separable and physically integral stimuli. Stimulus displays were varied in terms of the redundancy of the irrelevant non-cued dimensions—i.e. control, correlated, and orthogonal conditions within Garner's (1974a) framework—and selective readout performance was measured. The results demonstrate that, in initial processing, physically separable dimensions (e.g., circle size vs. angle of radial line) can be selectively attended to as independent dimensions, but physically integral dimensions (e.g., size vs. brightness and height vs. width) can only be represented as wholistic integral objects. Implications of these findings for current models of feature integration and perceptual development are discussed.  相似文献   
92.
93.
Recent research has questioned the validity of identifying depression and anxiety as separate constructs in children. The current investigation examined the usefulness of the Positive and Negative Affect Schedule for Children (PANAS-C) in differentiating between anxiety and depression in children while also providing needed reliability and validity data on the PANAS-C. In addition, the relationship between positive and negative affect and coping was examined. Subjects included 110 third through fifth graders from a semirural public school setting. Children completed the PANAS-C, as well as self-report measures of depression, anxiety, and coping strategies. Moderate item–total correlations and high internal consistency indicated that the PANAS-C has good reliability. Validity results were mixed: a two-factor solution resembled previous studies, and negative affect was associated with avoidance coping strategies whereas positive affect was associated with approach coping strategies, as expected. However, correlations of positive and negative affect, anxiety, and depression scales suggest that positive and negative affectivity are negatively related in children as opposed to separate and independent constructs. Results of the present investigation question the validity of the use of the PANAS-C for differentiating anxiety and depression with this age group and lend support to the possibility that high overlap between anxiety and depression in this age group may be specific for childhood depression.  相似文献   
94.
The author describes a published symposium which debated “Is Critical Thinking Biased?” The symposium meant to address concerns about critical thinking that are being expressed by feminist and postmodern scholars. However, through the author's critique, and the symposium respondent's, we learn the participants ended up begging the question of bias. The author maintains that the belief that critical thinking is “unbiased” is based on an assumption that knowers can be separated from what is known. She argues that critical thinking is a tool which has no life of its own, it only has meaning and purpose when fallible, biased people use it (weak sense bias). She challenges the idea of a transcendental epistemological perspective, thus all knowledge is provisional and perspectival (strong sense bias). The author begins to redescribe a transformed critical thinking as constructive thinking.  相似文献   
95.
This study examined whether singular/plural marking in a language helps children learn the meanings of the words 'one,' 'two,' and 'three.' First, CHILDES data in English, Russian (which marks singular/plural), and Japanese (which does not) were compared for frequency, variability, and contexts of number-word use. Then young children in the USA, Russia, and Japan were tested on Counting and Give-N tasks. More English and Russian learners knew the meaning of each number word than Japanese learners, regardless of whether singular/plural cues appeared in the task itself (e.g., "Give two apples" vs. "Give two"). These results suggest that the learning of "one," "two" and "three" is supported by the conceptual framework of grammatical number, rather than that of integers.  相似文献   
96.
Previous research suggests that, during visual search and discrimination tasks, older adults place greater emphasis than younger adults on top-down attention. This experiment investigated the relative contribution of target activation and distractor inhibition to this age difference. Younger and older adults performed a singleton discrimination task in which either an E or an R target (colour singleton) was present among distractor letters. Relative to a baseline condition in which the colours of the targets and distractors remained constant, an age-related slowing of performance was evident when either the colour of the target or that of the distractors varied across trials. The age-related slowing was more pronounced in response to target colour variation, suggesting that older adults place relatively greater emphasis on the top-down activation of target features.  相似文献   
97.
The self-reporting of cancer history is becoming increasingly important, as it frequently guides medical decision-making. We studied the accuracy of personal cancer history using a self-administered questionnaire, comparing the results with the Tumor Registry at our institution. Among 39,662 records, we identified 3614 women with a single cancer in the Tumor Registry who reported none or one cancer on their questionnaire. The sensitivity in self-reporting cancers was 85.7%, ranging from 92.1% for breast cancer to 42.9% for leukemia. The accuracy for breast cancer and Hodgkin's Lymphoma was significantly better than other cancers (p=0.00027, CI: 1.4–3.88). Analysis of patient's characteristics showed that Caucasians reported breast cancer more accurately than Asian/Pacific Islanders (p=0.008), and those with Jewish ancestry more accurately than non-Jewish (p=0.0435). These results will help us to improve data collection and thus improve medical decision-making.  相似文献   
98.
We examined the ability of domestic dogs to choose the larger versus smaller quantity of food in two experiments. In experiment 1, we investigated the ability of 29 dogs (results from 18 dogs were used in the data analysis) to discriminate between two quantities of food presented in eight different combinations. Choices were simultaneously presented and visually available at the time of choice. Overall, subjects chose the larger quantity more often than the smaller quantity, but they found numerically close comparisons more difficult. In experiment 2, we tested two dogs from experiment 1 under three conditions. In condition 1, we used similar methods from experiment 1 and tested the dogs multiple times on the eight combinations from experiment 1 plus one additional combination. In conditions 2 and 3, the food was visually unavailable to the subjects at the time of choice, but in condition 2, food choices were viewed simultaneously before being made visually unavailable, and in condition 3, they were viewed successively. In these last two conditions, and especially in condition 3, the dogs had to keep track of quantities mentally in order to choose optimally. Subjects still chose the larger quantity more often than the smaller quantity when the food was not simultaneously visible at the time of choice. Olfactory cues and inadvertent cuing by the experimenter were excluded as mechanisms for choosing larger quantities. The results suggest that, like apes tested on similar tasks, some dogs can form internal representations and make mental comparisons of quantity.  相似文献   
99.
Behavioural problems are a key feature of frontotemporal lobar degeneration (FTLD). Also, FTLD patients show impairments in emotion processing. Specifically, the perception of negative emotional facial expressions is affected. Generally, however, negative emotional expressions are regarded as more difficult to recognize than positive ones, which thus may have been a confounding factor in previous studies. Also, ceiling effects are often present on emotion recognition tasks using full-blown emotional facial expressions. In the present study with FTLD patients, we examined the perception of sadness, anger, fear, happiness, surprise and disgust at different emotional intensities on morphed facial expressions to take task difficulty into account. Results showed that our FTLD patients were specifically impaired at the recognition of the emotion anger. Also, the patients performed worse than the controls on recognition of surprise, but performed at control levels on disgust, happiness, sadness and fear. These findings corroborate and extend previous results showing deficits in emotion perception in FTLD.  相似文献   
100.
Suicide remains a leading cause of death among youth, and suicide ideation and behavior are relatively common in both normal and clinical populations. Clinicians working with young people must assess for the presence of suicidal ideation, suicidal behavior, and other risk factors, in order to determine the level of risk. This paper provides the clinician with a summary of risk factors for youth suicide, as well as providing standardized terminology to enhance assessment of suicidal ideation and behavior.  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