全文获取类型
收费全文 | 2317篇 |
免费 | 103篇 |
出版年
2021年 | 19篇 |
2020年 | 37篇 |
2019年 | 35篇 |
2018年 | 58篇 |
2017年 | 59篇 |
2016年 | 57篇 |
2015年 | 50篇 |
2014年 | 52篇 |
2013年 | 246篇 |
2012年 | 81篇 |
2011年 | 96篇 |
2010年 | 54篇 |
2009年 | 64篇 |
2008年 | 101篇 |
2007年 | 83篇 |
2006年 | 91篇 |
2005年 | 71篇 |
2004年 | 73篇 |
2003年 | 53篇 |
2002年 | 67篇 |
2001年 | 41篇 |
2000年 | 56篇 |
1999年 | 51篇 |
1998年 | 31篇 |
1997年 | 24篇 |
1996年 | 27篇 |
1993年 | 23篇 |
1992年 | 40篇 |
1991年 | 28篇 |
1990年 | 36篇 |
1989年 | 24篇 |
1988年 | 36篇 |
1987年 | 34篇 |
1986年 | 17篇 |
1985年 | 29篇 |
1984年 | 21篇 |
1983年 | 21篇 |
1980年 | 17篇 |
1979年 | 34篇 |
1977年 | 17篇 |
1976年 | 28篇 |
1975年 | 22篇 |
1974年 | 21篇 |
1973年 | 22篇 |
1972年 | 20篇 |
1971年 | 23篇 |
1969年 | 16篇 |
1968年 | 27篇 |
1967年 | 19篇 |
1966年 | 19篇 |
排序方式: 共有2420条查询结果,搜索用时 15 毫秒
901.
S W Brown M C Welsh E E Labbé W F Vitulli P Kulkarni 《Perceptual and motor skills》1992,74(2):555-560
A small group of psychiatrically institutionalized adolescents (16 boys, 11 girls) were assigned to a three-day-per-week running/aerobic exercise program or a regular physical activity class. The complete program continued over 9 weeks, with 11 subjects remaining throughout the program. Dependent measures of body-mass index, timed performance on a one-mile run, resting, exercise, and recovery heart rates, and measures of depression, mood-states, and self-efficacy were assessed pre-, mid-, and post-9-wk. treatment and at a 4-wk. follow-up. Improvements in depression, anxiety, hostility, confused thinking, and fatigue were shown in treated girls, with increases in vigor and self-efficacy for all treated subjects. 相似文献
902.
Ethnic differences in adolescent achievement. An ecological perspective. 总被引:15,自引:0,他引:15
Using data collected from a large sample of high school students, the authors challenge three widely held explanations for the superior school performance of Asian-American adolescents, and the inferior performance of African- and Hispanic-American adolescents: group differences in (a) parenting practices, (b) familial values about education, and (c) youngsters' beliefs about the occupational rewards of academic success. They found that White youngsters benefit from the combination of authoritative parenting and peer support for achievement, whereas Hispanic youngsters suffer from a combination of parental authoritarianism and low peer support. Among Asian-American students, peer support for academic excellence offsets the negative consequences of authoritarian parenting. Among African-American youngsters, the absence of peer support for achievement undermines the positive influence of authoritative parenting. 相似文献
903.
904.
Five experiments measured reaction time (RT) to detect the presence or absence of a simple volumetric shape (target) dependent on the number of display items (distractors) and their depicted three-dimensional (3-D) orientation. Experiments 1-4 examined every pairwise combination of two different simple volumetric shapes in two 3-D orientations. Conditions exhibiting "pop-out" could be predicted by differences in their two-dimensional (2-D) features. Conditions in which search was slower support previously found search asymmetries for particular 2-D features. When the distractors were a mixture of the other shapes in the same 3-D orientation, search was serial, except when the target had a curved principal axis (Experiment 5). The results suggest that these simple volumetric shapes are not processed preattentively. 相似文献
905.
Few empirical studies have been conducted to determine the influence of hospitalization on adolescents' psychosocial processes because younger children are regarded as more vulnerable. Therefore, the purpose of this self-report, retrospective study of 115 adolescents was to compare the self-esteem and locus of control of the never hospitalized to that of adolescents hospitalized during adolescence, prior to adolescence, and during and prior to adolescence. Although no significant differences were found, the findings raise questions about long-term effects of early experiences, especially among lower socioeconomic status youth. Also, general measures of self-esteem and locus of control may be unable to determine situation-specific effects. 相似文献
906.
Recent studies of single-word processing in dyslexic populations have focused on the differential predictions made by ‘delay’ and ‘deviance’ models. Many experiments in this area have sought to determine whether the reading process in dyslexia is idiosyncratic or similar to processing in younger non-dyslexic readers. Most relevant research has, however, failed to take account of recent developments in theoretical models of reading. Furthermore, relatively little research has examined the reading behaviour of ‘highly compensated’ subjects, who achieve high-level academic qualifications despite their developmental dyslexia. The present paper examines such a population, and concludes that its single-word reading is governed by the same spelling-to-sound word characteristics as reading by other groups. The implications of the results for the deviance/delay hypothesis and for models of word naming are discussed. 相似文献
907.
S D Brown R J Dooling 《Journal of comparative psychology (Washington, D.C. : 1983)》1992,106(3):203-216
Perception of faces by 4 budgerigars (Melopsittacus undulatus), a species of small parrot, was studied with a same-different discrimination task. Reaction times were taken as a measure of the similarity between pairs of faces and analyzed with multidimensional scaling to reveal patterns of similarity among the faces. The perception of natural faces was tested to determine which characteristics were perceptually salient. Color, patterns of markings, darkness of the iris, and size of the pupil corresponded to the observed patterns of similarity among the faces. Differences among budgerigar faces were more salient than differences among zebra finch faces, and budgerigar faces were perceptually distinct from the faces of other avian species. The results from these experiments provide a basis for understanding the ways in which these signals function in the coordination of social behaviors. 相似文献
908.
This study of college women examines the relationship among sex-role attitudes, curriculum choice, and levels of educational and occupational aspirations and expectations. Data for analysis are from a 1977 survey of college students enrolled in home economics and agricultural curriculums in all southern land grant colleges and universities. Results show that sex-role ideology is only weakly associated with curriculum choice but is related to career ambitions for women in sex-typical and sex-atypical areas of study. 相似文献
909.
910.