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   4788篇
  免费   547篇
  国内免费   344篇
  2024年   17篇
  2023年   184篇
  2022年   64篇
  2021年   140篇
  2020年   275篇
  2019年   314篇
  2018年   221篇
  2017年   283篇
  2016年   273篇
  2015年   208篇
  2014年   226篇
  2013年   699篇
  2012年   144篇
  2011年   214篇
  2010年   171篇
  2009年   223篇
  2008年   247篇
  2007年   215篇
  2006年   226篇
  2005年   190篇
  2004年   180篇
  2003年   166篇
  2002年   157篇
  2001年   106篇
  2000年   85篇
  1999年   52篇
  1998年   58篇
  1997年   31篇
  1996年   54篇
  1995年   42篇
  1994年   36篇
  1993年   26篇
  1992年   29篇
  1991年   6篇
  1990年   11篇
  1989年   12篇
  1988年   5篇
  1987年   6篇
  1986年   6篇
  1985年   12篇
  1984年   14篇
  1983年   10篇
  1982年   3篇
  1981年   6篇
  1980年   6篇
  1979年   3篇
  1978年   6篇
  1977年   12篇
  1976年   2篇
  1975年   3篇
排序方式: 共有5679条查询结果,搜索用时 15 毫秒
91.
Four rhesus monkeys were trained to respond on one key when a one-second noise burst was presented through one speaker and to respond on a second key when the noise burst was presented through a second speaker. The acquisition of stimulus control was studied under three conditions, in each of which the relationship between the sound source and the response-key positions varied: an adjacent condition in which the noise burst was presented through the key and a response on this key was reinforced; a reversed-adjacent condition in which the noise burst was presented through one key and responding on the other key was reinforced: and a nonadiacent condition in which responding on the key nearer the sound was reinforced. Under adjacent conditions, stimulus control developed within one or two sessions. Under reversed and nonadjacent conditions, 10 sessions were required for the development of control. The asymptote of correct responding was the same under each condition in all animals.  相似文献   
92.
Hoben Thomas 《Psychometrika》1977,42(2):199-206
Individuals are classified in a cross-classification table where two behavioral observations on each individual determine the classification. The problem is to test certain structural models assumed to underlie the cross-classified observations. A minimum chi-square test procedure is proposed.  相似文献   
93.
94.
Abstract: Joining a vast Wittgensteinian anti‐theoretical movement, John Canfield has argued that it is possible to read the claims that (1) “language is essentially communal” and (2) “it is conceptually possible that a Crusoe isolated from birth should speak or follow rules” in such a way that they are perfectly compatible, and, indeed, that Wittgenstein held them both at once. The key to doing this is to drain them of any theoretical content or implications that would put each claim at odds with the other. I argue here, first of all, that it is not possible to detheorize both (1) and (2) and still hope to say anything illuminating about the nature of language. In fact, Canfield himself does not succeed in detheorizing both (1) and (2) but ends up trivializing (1) and leaving (2) with quite a bit of theoretical content. I further argue, however, that this is getting the matter the wrong way around. Contra Canfield et al., it is only when we recognize this that we can appreciate how radical and innovative Wittgenstein's claims about language really are.  相似文献   
95.
Lyman A. Page 《Zygon》2007,42(3):767-778
Progress in technology has allowed dynamic research on the development of the human brain that has revolutionized concepts. Particularly, the notions of plasticity, neuronal selection, and the effects of afferent stimuli have entered into thinking about brain development. Here I focus on development from the age of four years to early adulthood, during which a 30 percent reduction in some brain synapses occurs that is out of proportion to changes in neuronal numbers. This corresponds temporally with changes in normal child behavior from the loose‐associative, almost schizoid, thinking and art of the four‐year‐old to the more trained, or disciplined, or acculturated—and restrained—personality of the young adult. I propose that the synaptic changes can best be thought of as a winnowing process likely subject to environmental influences. Acquisition of language and the ability to link linguistic cognition to the plastic development of the brain provide a potentially powerful means of explaining the evolutionally explosive development of human cognition and culture. Schizophrenia, a disease that can be envisioned as representing a derangement of synaptic maturation, may provide an entry into the search for genes controlling the processes mediating the unprecedented development of Homo sapiens over the past 40,000 to 70,000 years. The recently completed mapping of the genome of the chimpanzee provides a new frame of reference that may speed the search.  相似文献   
96.
97.
青少年早期抑郁和自伤的联合发展轨迹:人际因素的作用   总被引:1,自引:0,他引:1  
通过对859名初中生历时3年的3次追踪测量, 考察了抑郁和自伤的独立与联合发展轨迹, 并对3种重要人际关系(亲子关系、同伴关系、师生关系)在二者联合发展中的作用进行检验。结果发现, 青少年早期抑郁和自伤分别呈现4条和3条异质性发展轨迹; 二者的联合发展轨迹包含“低抑郁-低自伤-稳定”、“低抑郁-低自伤-增长”、“中抑郁-中自伤-降低”三类; 父母心理控制和同伴接纳分别为青少年早期抑郁和自伤的风险与保护性因素。  相似文献   
98.
Preterm birth is a risk factor for problems in interactions with others. We compared the difference in socioemotional development between hospital discharge and at six months of corrected age of infants born ≤32 weeks and assessed the impact of maternal and infantile factors on socioemotional development rate within a 6 month’s period. Mother-child dyads (n = 144) were assessed by the Mother-Baby Observation Protocol 0–6 months through a video microanalysis. Multivariate model was built. Neonatal, maternal and child factors were associated with interactive gaze, initiate contact, responsiveness, infantile vocalization, and thus contributed to the socioemocional development of preterm infants with their mothers.  相似文献   
99.
To systematically examine the relation between motor milestone onset and disruption of night sleep in infancy, three families kept microgenetic, prospective, daily checklist diaries of their infants’ motor behavior and sleep (197-313 observation days; 19,000 diary entries). Process control and interrupted time series analyses examined whether deviations from the moving average for night wakings and evening sleep duration were temporally linked to motor skill onset and tested for meaningful differences in individual sleep patterns before and after skill onset. Model assumptions defined skill onset as first day of occurrence or as mastery and moving average windows as 3, 7, or 14 days. Changes in infants’ sleep patterns were associated with changing expertise for motor milestones. The temporal relation varied depending on infant and sleep parameter. Intensive longitudinal data collection may increase our understanding of micro-events in infant development.  相似文献   
100.
Language skills and mathematical competencies are argued to influence each other during development. While a relation between the development of vocabulary size and mathematical skills is already documented in the literature, this study further examines how children’s ability to map a novel word to an unknown object as well as their ability to retain this word from memory may be related to their knowledge of number words. Twenty-five children were tested longitudinally (at 30 and at 36 months of age) using an eye-tracking-based fast mapping task, the Give-a-Number task, and standardized measures of vocabulary. The results reveal that children’s ability to create and retain a mental representation of a novel word was related to number knowledge at 30 months, but not at 36 months while vocabulary size correlated with number knowledge only at 36 months. These results show that even specific mapping processes are initially related to the acquisition of number words and they speak for a parallelism between the development of lexical and number-concept knowledge despite their semantic and syntactic differences.  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