全文获取类型
收费全文 | 83289篇 |
免费 | 3360篇 |
国内免费 | 29篇 |
专业分类
86678篇 |
出版年
2020年 | 929篇 |
2019年 | 1101篇 |
2018年 | 1571篇 |
2017年 | 1566篇 |
2016年 | 1675篇 |
2015年 | 1185篇 |
2014年 | 1438篇 |
2013年 | 7440篇 |
2012年 | 2621篇 |
2011年 | 2668篇 |
2010年 | 1636篇 |
2009年 | 1639篇 |
2008年 | 2357篇 |
2007年 | 2255篇 |
2006年 | 2088篇 |
2005年 | 1747篇 |
2004年 | 1790篇 |
2003年 | 1742篇 |
2002年 | 1653篇 |
2001年 | 2704篇 |
2000年 | 2540篇 |
1999年 | 1951篇 |
1998年 | 922篇 |
1997年 | 803篇 |
1996年 | 962篇 |
1995年 | 890篇 |
1994年 | 872篇 |
1993年 | 819篇 |
1992年 | 1743篇 |
1991年 | 1578篇 |
1990年 | 1586篇 |
1989年 | 1459篇 |
1988年 | 1445篇 |
1987年 | 1361篇 |
1986年 | 1329篇 |
1985年 | 1390篇 |
1984年 | 1182篇 |
1983年 | 1001篇 |
1979年 | 1191篇 |
1978年 | 865篇 |
1975年 | 1022篇 |
1974年 | 1092篇 |
1973年 | 1161篇 |
1972年 | 1029篇 |
1971年 | 935篇 |
1970年 | 808篇 |
1969年 | 787篇 |
1968年 | 1018篇 |
1967年 | 891篇 |
1966年 | 850篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
An electronic apparatus using infrared beams for monitoring the movements of individual bees under dark conditions is described. The searching behavior of workers in an arena was monitored over 2-h periods. Mean ambulatory velocity for one bee over a distance of 100 mm was 45.6±1.51 mm/sec (n=45). Thigmokinesis and temporal activity patterns are illustrated. 相似文献
44.
45.
Erin M. Leddon Sandra R. Waxman Douglas L. Medin 《The British journal of developmental psychology》2011,29(3):375-395
Previous work on children's intuitive knowledge about the natural world has documented their difficulty in acquiring an overarching concept of biological life that includes plants as well as humans and non‐human animals. It has also suggested that the acquisition of fundamental biological concepts like alive and die may be influenced by the language used to describe them, as evidenced by differences between English‐ and Indonesian‐speaking children's performance in tasks involving these concepts. Here, we examine one particularly important source of linguistic information available to children during this acquisition process: everyday conversations with their parents. We take a cross‐linguistic approach in analysing the evidence available to English‐ and Indonesian‐speaking children as they acquire meanings for words corresponding to the concepts alive and die . Our analysis illustrates that young children acquiring English and Indonesian are faced with distinct problems, but that parental input in both languages does little to support the acquisition of broad, inclusive biological concepts. 相似文献
46.
47.
Vladimir M. Sloutsky Yevgeniya Goldvarg 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》2004,57(4):636-665
Logical connectives, such as “AND”, “OR”, “IF . . . THEN”, and “IF AND ONLY IF” are ubiquitous in both language and cognition; however, reasoning with logical connectives is error-prone. We argue that some of these errors may stem from people's tendency to minimize the number of possibilities compatible with logical connectives and to construct a “minimalist” one-possibility representation. As a result, connectives denoting a single possibility (e.g., conjunctions) are likely to be represented correctly, whereas connectives denoting multiple possibilities (e.g., disjunctions or conditionals) are likely to be erroneously represented as conjunctions. These predictions were tested and confirmed in three experiments using different paradigms. In Experiment 1, participants were presented with a multiple-choice task and asked to select all and only those possibilities that would indicate that compound verbal propositions were true versus false. In Experiment 2, a somewhat similar task was used, except that participants were asked later to perform a cued recall of verbal propositions. Finally, Experiment 3 used an old/new recognition paradigm to examine participants' ability to accurately recognize different logical connectives. The results of the three experiments are discussed in relation to theories of representation of possibilities and theories of reasoning. 相似文献
48.
Extensive empirical evidence confirms a depressed entitlement effect wherein women pay themselves less than men for comparable work and believe the allocation fair. The present study tests the hypothesis that status subordination linked to being female underlies at least some of this effect. A 2 × 3 design crossed 180 undergraduates' gender with a control condition, which successfully established the depressed entitlement effect, and two experimental conditions. In one, women's status was enhanced through legitimation of women's task abilities; in the other, both women's and men's status was enhanced by adding educational credentials relevant to task ability. Follow-up analyses of the significant interaction revealed that the gap in self-pay demonstrated in the control condition disappeared when women's status was enhanced such that higher-status women's self-pay equaled that of men and exceeded that of control women. Although these findings confirm that status plays a role in producing depressed entitlement in self-pay, ancillary analyses of participants' perceptions point to the persistence of shifting standards and men's resistance to status threats. 相似文献
49.
50.