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   18409篇
  免费   867篇
  国内免费   8篇
  2020年   229篇
  2019年   233篇
  2018年   349篇
  2017年   336篇
  2016年   394篇
  2015年   307篇
  2014年   377篇
  2013年   1578篇
  2012年   634篇
  2011年   554篇
  2010年   382篇
  2009年   379篇
  2008年   495篇
  2007年   507篇
  2006年   435篇
  2005年   403篇
  2004年   370篇
  2003年   320篇
  2002年   347篇
  2001年   702篇
  2000年   690篇
  1999年   488篇
  1998年   199篇
  1997年   193篇
  1996年   191篇
  1992年   393篇
  1991年   365篇
  1990年   377篇
  1989年   323篇
  1988年   314篇
  1987年   304篇
  1986年   284篇
  1985年   279篇
  1984年   272篇
  1983年   233篇
  1982年   186篇
  1981年   165篇
  1979年   258篇
  1978年   195篇
  1977年   168篇
  1975年   208篇
  1974年   260篇
  1973年   248篇
  1972年   204篇
  1971年   201篇
  1970年   163篇
  1969年   195篇
  1968年   226篇
  1967年   213篇
  1966年   184篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Multidimensional studies of Munsell color solid   总被引:1,自引:0,他引:1  
  相似文献   
82.
Strings of four unrelated letters were presented for subjects to identify, followed by a patterned mask and then a forced choice test of each letter position. In Experiment 1, the type style in the regular conditions was consistent--all of the letters were of a single type font--whereas in the mixed condition, each string contained letters from two type fonts. Compared with the mixed condition, accuracy in the regular conditions was higher overall and increased at a faster rate as a function of processing time. This held across four sessions. In Experiment 2, the font in the mixed condition was varied either between or within letter strings; sizeable advantages for the regular conditions were found with both mix-methods. The results are consistent with the idea of a schemalike perceptual system that becomes tuned to the regularities of a particular font in order to process visual information efficiently.  相似文献   
83.
Seven severely nonfluent aphasics and one relative or close friend were investigated in an interview situation. The conversation was videotaped and analyzed for the use of nonverbal communication between aphasic and partner. The results indicate that the group of aphasics used significantly more frequently and for a significantly longer period of time nonverbal channels of communication than their healthy partners. The aphasic patients also used significantly fewer speech-focused movements and significantly more codified gestures. Nonverbal elements were more frequently used as speech substitutes by the group of aphasics.  相似文献   
84.
Sprague-Dawley rats drank sweetened (3% dextrose + 0.144% saccharin, w/v) or unflavored water for 18 days and subsequent pain reactivity was assessed using a hot plate. Compared to the rats that consumed unflavored water, the rats that consumed sweet water responded more quickly on the hot plate indicating that their threshold for pain was lowered. Another group of rats given identical exposure to the fluids had their brains prepared for measuring opiate receptor binding using the delta-receptor ligand [3H]D-Ala-D-Leu-enkephalin ([3H]DADLE) and the mu-receptor selective ligand [3H]Tyr-D-Ala-Gly-MePhe-Gly-ol ([ 3H]DAGO). Binding of these opiates to mu- and delta-receptors in the cerebral cortex, striatum, hippocampus, hypothalamus, brain stem, and remaining brain regions was the same for the rats that drank sweet fluids and those that drank unflavored water. These findings suggest that drinking sweet fluids lowers pain thresholds but does not alter mu- and delta-receptors.  相似文献   
85.
This study examined the relations of gender and three aspects of gender roles — self concept, behavior, and sexual attitudes — to three aspects of sexual behavior — sexual experience, reasons for intercourse, and contraceptive use. Gender was strongly related to all three aspects of sexual behavior. For both men and women, sex role behaviors were related to sexual experience and to reasons for intercourse, but not to contraceptive use, and sex role self-concept was unrelated to any of the aspects of sexual behavior. The results indicate that sexual behavior is influenced both by societal gender role norms and by individual differences in the acceptance of those norms.  相似文献   
86.
87.
88.
A philosophical movement, correctly called logical pragmatism, is growing up around the philosophy of W. V. O. Quine, Soviet scholars follow this development with clear and well-grounded understanding of the origins and tenets of the system. This essay continues the dialogue between contemporary Marxism-Leninism and logical pragmatism recommended by Soviet scholars.A Russian translation of this article is being published inFilosofskie nauki (Moscow).  相似文献   
89.
Attitudes toward older and younger adults: a meta-analysis   总被引:3,自引:0,他引:3  
Attitudes toward the elderly have been examined in a number of empirical studies, yet the question of whether the elderly are viewed more negatively than younger persons has not been resolved. A meta-analysis of the literature was conducted to examine this question; results demonstrated that attitudes toward the elderly are more negative than attitudes toward younger people. However, smaller differences between the evaluations of elderly and younger targets were found when (a) the study used measures of personality traits (compared with measures of competence), (b) there were a larger number of dependent measures included in the effect size, (c) specific information was provided about the target person (compared with when a general target such as old person was used), and (d) a between-subjects design (compared with a within-subjects design) was used. These results support Lutsky's (1981) conclusion that age, in and of itself, seems to be less important in determining attitudes toward the elderly than other types of information. The methodological limitations within the literature and a need to consider multiple components of attitudes toward older individuals are discussed.  相似文献   
90.
We investigated longitudinally the effects of a stroke on the social support systems and well-being of the patient's primary support person, both acutely and as the condition stabilized. Individuals who had suffered a first stroke and a primary support person participated in two waves of data collection, carried out in 6-month intervals beginning 7 weeks after the stroke. Our data show that the prevalence of depressive symptoms is from 2 1/2 to 3 1/2 times higher than rates found among representative samples of middle-aged and elderly populations. Mean level of depression did not change over time, although level of optimism declined significantly. Multiple regression analyses showed that levels of depression and perceived burden in support persons are highly related to aspects of the stroke such as its severity, and that demographic variables such as age and income play a relatively minor role in attenuating these relations in the acute adjustment phase. However, from 7 to 9 months after the stroke, well-established demographic variables such as health, income, and age were significant predictors of depression. Individuals who were older and who had good health and higher incomes were least depressed.  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