全文获取类型
收费全文 | 2123篇 |
免费 | 77篇 |
国内免费 | 1篇 |
专业分类
2201篇 |
出版年
2021年 | 17篇 |
2020年 | 28篇 |
2019年 | 23篇 |
2018年 | 44篇 |
2017年 | 49篇 |
2016年 | 42篇 |
2015年 | 41篇 |
2014年 | 36篇 |
2013年 | 220篇 |
2012年 | 83篇 |
2011年 | 87篇 |
2010年 | 47篇 |
2009年 | 47篇 |
2008年 | 69篇 |
2007年 | 86篇 |
2006年 | 72篇 |
2005年 | 75篇 |
2004年 | 78篇 |
2003年 | 74篇 |
2002年 | 83篇 |
2001年 | 51篇 |
2000年 | 39篇 |
1999年 | 32篇 |
1998年 | 27篇 |
1997年 | 21篇 |
1996年 | 33篇 |
1995年 | 27篇 |
1994年 | 25篇 |
1993年 | 30篇 |
1992年 | 23篇 |
1991年 | 25篇 |
1990年 | 45篇 |
1989年 | 26篇 |
1988年 | 22篇 |
1987年 | 22篇 |
1986年 | 22篇 |
1985年 | 27篇 |
1984年 | 40篇 |
1983年 | 28篇 |
1982年 | 27篇 |
1981年 | 29篇 |
1980年 | 29篇 |
1979年 | 24篇 |
1978年 | 36篇 |
1977年 | 19篇 |
1976年 | 24篇 |
1975年 | 28篇 |
1974年 | 27篇 |
1973年 | 19篇 |
1969年 | 13篇 |
排序方式: 共有2201条查询结果,搜索用时 15 毫秒
21.
Several inherent limitations to secondary school sex education program evaluations are: limited generalizability, lack of longitudinal research, and no clear consensus of program outcomes. With a Bureau of Health Education, Center for Disease Control study as the criterion for program outcomes, a study was undertaken to examine the immediate and long-term impact of sex education upon program participants. Two of the 20 schools in the CDC study identified as having exemplary sex education programs provided access to their students and alumni. Inventories which measured perceived achievement of 33 sex education outcomes were piloted for reliability and validity. Each inventory examined participant changes in knowledge, understanding of self, values, interaction skills, self-esteem, and fear of sex-related activities. Students were surveyed in school; alumni were surveyed through the mail. Response rates ranged from 30 to 100 percent for students and alumni at both schools. Overall there was no statistically significant difference between the perceptions of students and alumni as to achievement of investigated outcomes. Alumni responses at one school did, however, indicate some potentially weak areas of their school's program with respect to values and interaction skills outcomes. It appears that program impact may decrease with time. Thus, isolating and addressing the factors involved may be necessary. This would assist program planners and instructors to strengthen curricula and program activities in order to enhance the overall impact of sex education. The present study supports the notion that positive gains are achieved as a result of each school's sex education program, and these gains remained over time. 相似文献
22.
Dr. Jeffrey M. Halperin Rachel Gittelman Donald F. Klein Rita G. Rudel 《Journal of abnormal child psychology》1984,12(1):1-14
Mixed hyperactive/reading-disabled children, selected from a large sample of hyperactive children, were compared to pure hyperactive children on demographic, behavioral, and neuropsychological measures. Children in the Mixed group were reading-disabled relative to age and IQ; those in the Pure group had achievement scores that were average relative to age and IQ. The Mixed group was significantly older than the Pure group; there were no differences in gender, race, or socioeconomic status. Behaviorally, the groups did not differ significantly on teacher ratings or on psychiatric ratings of aggression. The Mixed group had a significantly higher Performance IQ, whereas the Pure group had a significantly higher Verbal IQ and performed better on measures of cognitive impulsivity. Several other measures failed to distinguish the groups. The data give minimal support to the notion that pure hyperactive and mixed hyperative/reading-disabled children constitute distinct subgroups of Attention Deficit Disorder with Hyperactivity.This research was supported in part by Mental Health Clinical Research Grant MH-30906 and by U. S. Public Health Service Grant MH-18579. 相似文献
23.
24.
Emerging independence in nursing graduates: An analysis of traditional-nontraditional value patterns
The study sought to determine whether current nursing graduates value assertiveness, independence, and achievement to a greater degree than had past graduates, and whether selection or socialization might account for such a change. Scores on the Allport Vernon Lindsey Scale of Values for 55 1974 graduates of a private baccalaureate school of nursing were compared with 66 1980 graduates. Only scores on the political scale were significantly higher for the 1980 class. 1980 graduates displayed a traditional value pattern of high social and low political scores upon entering the educational program. Longitudinal comparison of scores for the 1980 class showed a significant rise in scores on the political scale; graduating scores did not differ significantly from college norms. The results suggest a rise in nontraditional values which is the result of the educational socialization process. 相似文献
25.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties. 相似文献
26.
27.
This experiment concerned the contribution of polydipsia on the temporal discrimination of rats during a fixed-interval 60-sec. schedule. In this study, the timing accuracy of 12 rats which had access to water during training was compared to that of 12 rats which had no water during training. The rats were trained for 25 sessions on an FI 60-sec. schedule. In early sessions before polydipsia was fully developed, no differences existed between the timing accuracy of the water group and no-water group. As the amount of water drunk by the water group increased as the number of sessions increased, a parallel increase was noted in the timing accuracy of the water group. In the final sessions, a significant difference was found between the timing accuracy of rats in the water group and that of those in the no-water group. It was concluded that polydipsia facilitated the development of the temporal discrimination which is characteristic of a fixed-interval 60-sec. schedule. 相似文献
28.
Nathan A. Bowling Kevin J. Eschleman Lucian Zelazny Gary Burns 《International Journal of Selection & Assessment》2023,31(1):163-174
Curmudgeon personality, which is assessed by having participants evaluate a heterogeneous set of attitude objects, provides an applied value beyond that of more established personality traits. Recent research, for instance, suggests that curmudgeon personality is distinct from the Five Factor Model personality traits and that it predicts unique variance in important criteria, such as job attitudes and well-being. In the current paper we contribute to this literature by testing an explanation of how curmudgeon personality is distinct from other traits—their potential resistance to response distortion. We estimated response distortion for scales of curmudgeon personality and FFM traits across two quasi-experimental studies. As expected, the score shifts between nonapplicant and applicant conditions were smaller for scales of curmudgeon personality compared to scales of emotional stability and conscientiousness. We argue that curmudgeon personality scales may be more resistant to response distortion than are measures of other traits because curmudgeon personality items are semi-implicit and lack an obvious desirable response. The resistance to response distortion should serve as a call to future researchers to test the criterion validity of curmudgeon personality in regard to performance criteria. 相似文献
29.
In a genetic analysis of PTC taste sensitivity of mice, Ss were presented tap water and a PTC solution in a two-choice situation. A preference index was used as a measure of taste sensitivity, assuming that ability to taste would lead to avoidance, i.e., negative preference. This assumption, however, lead to the rejection of seven Ss who preferred the test solution. Due to the undesirability of deleting Ss, the data were reanalyzed, using an alternative index of taste sensitivity that required no assumption concerning the hedonic quality of the test solution. Information regarding the inheritance of taste sensitivity to PTC provided the validating criterion for this measure. 相似文献
30.