全文获取类型
收费全文 | 2707篇 |
免费 | 102篇 |
出版年
2023年 | 16篇 |
2020年 | 36篇 |
2019年 | 42篇 |
2018年 | 56篇 |
2017年 | 69篇 |
2016年 | 67篇 |
2015年 | 65篇 |
2014年 | 53篇 |
2013年 | 252篇 |
2012年 | 99篇 |
2011年 | 104篇 |
2010年 | 68篇 |
2009年 | 71篇 |
2008年 | 98篇 |
2007年 | 94篇 |
2006年 | 96篇 |
2005年 | 75篇 |
2004年 | 82篇 |
2003年 | 93篇 |
2002年 | 99篇 |
2001年 | 40篇 |
2000年 | 36篇 |
1999年 | 50篇 |
1998年 | 51篇 |
1997年 | 53篇 |
1996年 | 33篇 |
1995年 | 39篇 |
1994年 | 48篇 |
1993年 | 47篇 |
1992年 | 56篇 |
1991年 | 36篇 |
1990年 | 45篇 |
1989年 | 31篇 |
1988年 | 33篇 |
1987年 | 35篇 |
1986年 | 31篇 |
1985年 | 29篇 |
1984年 | 37篇 |
1983年 | 34篇 |
1982年 | 26篇 |
1981年 | 33篇 |
1980年 | 32篇 |
1979年 | 41篇 |
1978年 | 34篇 |
1977年 | 23篇 |
1976年 | 37篇 |
1975年 | 19篇 |
1974年 | 21篇 |
1973年 | 21篇 |
1966年 | 15篇 |
排序方式: 共有2809条查询结果,搜索用时 15 毫秒
91.
In light of information uncovered about human radiation experiments conducted during the Cold War, an important charge for the Advisory Committee on Human Radiation Experiments was to assess the current state of protections for human research subjects. This assessment was designed to enhance the Committee's ability to make informed recommendations for the improvement of future policies and practices for the protection of research subjects. The Committee's examination of current protections revealed great improvement over those from the past, yet some problems remain. Although the data collected by the Committee highlight specific areas in need of attention, the Committee's work should be viewed in part as the beginning of a series of ongoing assessments of the adequacy and effectiveness of the protections afforded to human subjects. 相似文献
92.
The available literature indicates that: (a) experiences of childhood violence are associated with mediator variables, including antisocial behaviors and depressive symptomatology, that are themselves associated with development of alcohol problems and perpetration of partner violence for men in adulthood; (b) experiences of childhood violence and, more strongly, observation of interparental violence during childhood predict perpetration of partner violence in adulthood for males; (c) presence of partner violence is associated with certain types of alcohol problems for men; and (d) both partner violence and alcohol problems are associated with marital conflict. However, available research has often excluded important moderator variables, such as history of familial and parental alcohol problems and history of parental psychiatric disorders. Based on the available research, two indirect pathways between childhood violence and adulthood problems (i.e., alcohol problems and partner violence) are proposed as guides for future research in the areas of family violence and alcohol problems for men. Further, bidirectional associations between alcohol problems and partner violence are proposed. Finally, inclusion of important moderator and mediator variables in multivariate research designs is suggested. 相似文献
93.
Should the nation provide expensive care and scarce organs to convicted felons? We distinguish between two fields of justice: Medical Justice and Societal Justice. Although there is general acceptance within the medical profession that physicians may distribute limited treatments based solely on potential medical benefits without regard to nonmedical factors, that does not mean that society cannot impose limits based on societal factors. If a society considers the convicted felon to be a full member, then that person would be entitled to at least a “decent minimum” level of care — which might include access to scarce life-saving organs. However, if criminals forfeit their entitlement to the same level of medical care afforded to all members of society, they still would be entitled to a kind of “rudimentary decent minimum” granted to all persons on simple humanitarian grounds. Almost certainly this entitlement would not include access to organ transplants. 相似文献
94.
This paper reports the results of a panel study of young, white, rural women from Georgia, South Carolina, and Texas (N = 138). The study was primarily concerned with how social origin variables affected early educational and occupational orientations and how early states of these orientations affected the orientations themselves at a later point in time. The results indicated that mother's education had a greater effect than father's education, but in either case the effect is mediated by intervening influences such as early aspirations and expectations. These young women held very traditional status orientations (with 60% projecting the occupations of beautician, nurse, stenographer, or school teacher), and their orientations were quite stable between their sophomore and senior years in high school. Since there has been so little work reported on the status attainment process for women, and rural women in particular, this study does offer a limited insight into this phenomenon. 相似文献
95.
Leonard H. Epstein Gene G. Abel Frank Collins Lynn Parker Paul M. Cinciripini 《Behaviour research and therapy》1978,16(3):153-160
The relationship between levels of frontalis muscle activity and self-reports of pain was evaluated in two studies. In Study I frontalis muscle activity and self-reports of pain collected during biofeedback treatment of muscular contraction headache clients were correlated. In Study II frontalis EMG activity was increased and decreased using biofeedback techniques while concurrent reports of headache pain were recorded. The results of Study I indicated a significant relationship between EMG activity and reported headache pain for only two of the five subjects studied. The biofeedback procedures in Study II were associated with reliable increases and decreases in EMG activity. Concordance between EMG and pain reports occurred only during the EMG increase condition. Overall correlations were significant for one of the 2 subjects. The results suggest that EMG activity may not be sufficient to account for pain reports in all chronic headache clients, and variables other than EMG activity may be influencing reports of pain in some patients. 相似文献
96.
A field experiment was designed in which students approached sales personnel in 31 different retail settings, asking for help in selecting toys for a twin niece and nephew, 5 years of age. A majority of salesperson suggestions involved a sex-stereotypic selection of toys for both the male and the female child. Limited support was found for hypotheses that the responses of sales personnel would vary by retail setting (specialized toystore, department store, dimestore/discount store) and by sex of salesperson; responses did not vary by salesperson's age, however. Because more different toys are available for boys than for girls, female role expansion in children's play activities is a more likely outcome than sex-role convergence.This article is a revision of a paper presented at the annual meeting of the American Sociological Association, New York, August 1976. 相似文献
97.
Subjects created imaginal interpretations of classical music passages in accordance with themes which were either concrete and comprehensible or abstract and difficult to comprehend. Recognition memory for the musical passages was found to be superior in the former condition. The results support the hypothesis that meaningful interpretation of stimulus material is a major determinant of memory accuracy. The implications of the results for comparisons of music and language are also discussed. 相似文献
98.
99.
A field experiment investigated violation of the spacing norm which keeps distance between people in a particular type of crowding, high social density, when the number of people in an area is large but space is not necessarily restricted. The proportion of people passing a drinking fountain who drank from the fountain was observed in conditions of high and low social density and, for each of these densities, when a confederate stood one foot from the fountain and when no one stood near the fountain. Three hundred passersby were observed in each of the four conditions. The observations supported the conclusion that the spacing norm was followed in low social density ( p <.01) but violated under conditions of high social density for reasons other than lack of space. Interpretation focused on several concomitants of high social density, especially excessive social stimulation, and the accompanying tendencies to attribute less of the usual social meanings to people and honor fewer of their expectations. 相似文献
100.
Several tests of Fear of Success (FOS), Fear of Failure (FOF), and Need Achievement (nAch), plus Taylor's Manifest Anxiety Scale and a social desirability scale were administered to 104 males and 101 females. FOS, FOF, and nAch did not show factor validity. Results for predictive validity were also poor. Anxiety defined the first factor in the factor analysis. All first-factor tests negatively predicted female grade point average and American College Test scores. All the first-factor tests showed sex differences, with females scoring higher. A clarifying role for anxiety in the study of sex differences in achievement is indicated. 相似文献