全文获取类型
收费全文 | 53043篇 |
免费 | 2294篇 |
国内免费 | 28篇 |
专业分类
55365篇 |
出版年
2020年 | 565篇 |
2019年 | 634篇 |
2018年 | 887篇 |
2017年 | 906篇 |
2016年 | 984篇 |
2015年 | 741篇 |
2014年 | 824篇 |
2013年 | 3782篇 |
2012年 | 1596篇 |
2011年 | 1630篇 |
2010年 | 1000篇 |
2009年 | 949篇 |
2008年 | 1368篇 |
2007年 | 1340篇 |
2006年 | 1167篇 |
2005年 | 1077篇 |
2004年 | 1039篇 |
2003年 | 960篇 |
2002年 | 962篇 |
2001年 | 1834篇 |
2000年 | 1762篇 |
1999年 | 1251篇 |
1998年 | 551篇 |
1997年 | 489篇 |
1992年 | 1136篇 |
1991年 | 1049篇 |
1990年 | 1086篇 |
1989年 | 976篇 |
1988年 | 966篇 |
1987年 | 911篇 |
1986年 | 968篇 |
1985年 | 1034篇 |
1984年 | 781篇 |
1983年 | 706篇 |
1982年 | 480篇 |
1981年 | 461篇 |
1979年 | 837篇 |
1978年 | 562篇 |
1977年 | 523篇 |
1976年 | 517篇 |
1975年 | 736篇 |
1974年 | 853篇 |
1973年 | 880篇 |
1972年 | 785篇 |
1971年 | 715篇 |
1970年 | 685篇 |
1969年 | 714篇 |
1968年 | 900篇 |
1967年 | 793篇 |
1966年 | 730篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
901.
T R Zentall P Jackson-Smith J A Jagielo G B Nallan 《Journal of experimental psychology. Animal behavior processes》1986,12(2):153-159
Categorical coding is the tendency to respond similarly to discriminated stimuli. Past research indicates that pigeons can categorize colors according to at least three spectral regions. Two present experiments assessed the categorical coding of shapes and the existence of a higher order color category (all colors). Pigeons were trained on two independent tasks (matching-to-sample, and oddity-from-sample). One task involved red and a plus sign, the other a circle and green. On test trials one of the two comparison stimuli from one task was replaced by one of the stimuli from the other task. Differential performance based on which of the two stimuli from the other task was introduced suggested categorical coding rules. In Experiment 1 evidence for the categorical coding of sample shapes was found. Categorical color coding was also found; however, it was the comparison stimuli rather than the samples that were categorically coded. Experiment 2 replicated the categorical shape sample effect and ruled out the possibility that the particular colors used were responsible for the categorical coding of comparison stimuli. Overall, the results indicate that pigeons can develop categorical rules involving shapes and colors and that the color categories can be hierarchical. 相似文献
902.
In an exploration of the social impacts of treatments for hyperactivity, two age groups (kindergarteners and first-graders vs. fourth- and fifth-graders) heard about a hyperactive child whose problem was treated either by an internal and controllable means (effort) or by an external and uncontrollable means (medication) and whose behavior either did or did not improve. The attributions and affective responses of both age groups were influenced by both the nature and the effectiveness of treatment, and there was only weak support for the hypothesis that younger children are more influenced by treatment outcome than older children are. However, older children, conforming to attribution theory predictions, held target children more accountabe for the success or failure of their own efforts than for the outcomes of medication, particularly valuing the child whose own efforts succeeded. By contrast, young children judged the child whose efforts failed as more worthy of pride and more likable than the child whose medication failed. Implications for peer acceptance of hyperactive children over the childhood years are discussed.Portions of this paper were presented at the annual meeting of the Southeastern Psychological Association, Atlanta, March 1985. Thanks are extended to the staff and students of the Model Laboratory School. 相似文献
903.
Measures adapted from social survey research were used to assess the quality of life of 33 end-stage renal disease (ESRD) patients in a 2-week test-retest design that varied both location and format of administration (hospital interview vs. home self-administered questionnaire). The measures were found to have substantial consistency over time, location, and format. These results indicate that quality of life is a stable construct and support the usefulness of questionnaire quality-of-life measures for evaluating medical interventions. 相似文献
904.
Health as a value: methodological and theoretical considerations 总被引:8,自引:0,他引:8
The concept of value placed on health is very important in several different theoretical approaches to the study of health behavior. In practice, however, health value is generally assumed to be universally high rather than being directly measured. If this assumption is incorrect, then theories that include health value have rarely been adequately tested. This paper presents a short 4-item Likert scale designed to measure the value placed on health. Norms from the utilization of this scale in five different samples are presented. Health value is found to increase with age among girls, but the increase apparently stops by late adolescence, before full adult levels of health value are achieved. Middle-aged women place a higher value on health than do middle-aged men, although no comparable sex difference appears in a sample of undergraduates. Consistent with theoretical predictions, both health locus of control beliefs and beliefs in the efficacy of certain preventive health behaviors correlate more highly with the performance of those same behaviors 5 to 9 months later among respondents who place a high value of health relative to those who do not value health so highly. However, this interaction is found only when it can be safely assumed that health is the primary value underlying the behavior. The importance of considering a variety of values in addition to health as possible motivators of preventive health behavior is stressed. 相似文献
905.
906.
T O Nelson R J Leonesio R S Landwehr L Narens 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(2):279-287
Distinctions are drawn between different predictors of an individual's memory performance, with emphasis on the notion of privileged access to idiosyncratic knowledge. Research is reported in which undergraduates attempted to recall the answers to general-information questions, then made feeling-of-knowing judgments on nonrecalled items, and subsequently had a criterion test (relearning, perceptual identification, or one of two versions of recognition). For predicting an individual's criterion performance, the individual's own feeling-of-knowing predictions were intermediate between two kinds of normative predictions: The individual's feeling-of-knowing predictions were more accurate than predictions derived from normative feeling-of-knowing ratings but were less accurate than predictions derived from base-rate item difficulty (normative probabilities of correct recall). Subsidiary analyses showed that factors other than unreliability are responsible for the partial inaccuracy of the individual's feeling of knowing. Ramifications are discussed for possible ways to improve the accuracy of an individual's feeling-of-knowing predictions. 相似文献
907.
Cognitive, motivational, social, and environmental influences on children's food choices 总被引:2,自引:0,他引:2
This study tested the applicability of a cognitive-motivational model of health behavior to children's food choices. A sample of 107 elementary schoolchildren provided ratings of 15 foods in terms of possible choice criteria (e.g., how tasty or healthful specific foods were) and social or environmental influences (e.g., whether foods were eaten by friends or were easy to get). Several measures of food consumption were taken, and cognitive-developmental level was assessed. Within-person correlations were calculated between food choices and each choice criterion and social/environmental factor. These "correlational indices" of influences on food choice subsequently were used to identify five distinct subgroups in the sample. Children at the operational level of cognitive development tended to be in one of three groups characterized by health orientation in food choice, taste orientation, or multiple-motive orientation. Dietary quality was poorest in the taste-oriented group. Children at the preoperational level tended to have one of two undifferentiated patterns of values across the correlational indices. Results provide evidence of: the viability of cognitive-motivational models to explain children's food choices, the promise of within-person research methodology, and the potential for enhanced health behavior-change programs by use of population segmentation and tailored interventions. 相似文献
908.
Relationship of physicians' nonverbal communication skill to patient satisfaction, appointment noncompliance, and physician workload 总被引:6,自引:0,他引:6
A field study of 28 residents in family practice was conducted. Physicians' self-reports of empathy, self-monitoring ability, and affective communication skill as well as their objectively measured nonverbal communication skills were examined as predictors of patient satisfaction, appointment noncompliance, and physician workload (schedule density). Physicians completed the Hogan Empathy Scale, Snyder Self-Monitoring Scale, Affective Communication Test, short form of the Profile of Nonverbal Sensitivity, and a nonverbal encoding task. Patient satisfaction with communication, affective care, and technical care was assessed using a 25-item, visit-specific satisfaction scale. Appointment records were used to determine the number of patients seen by each physician and the compliance of patients with scheduled appointments. Results indicated that the three self-report measures were unrelated to the measures of patient noncompliance and patient satisfaction, but self-reported affective communication ability was significantly correlated with physician workload. Objectively measured physician sensitivity to audio communication predicted patient compliance: More sensitive physicians experienced fewer unrescheduled appointment cancellations. Nonverbal encoding skill was significantly related to patient satisfaction with affective care and to physician workload. 相似文献
909.
MARY K. O'FARRELL CLARA E. HILL SUSAN M. PATTON 《Journal of counseling and development : JCD》1986,65(3):141-145
Process analyses revealed that interpretations and exploration of feelings were helpful across two cases. Other interventions were helpful for one case but not the other. 相似文献
910.
Numerous previous studies have shown that partial-interval sampling in direct observation systematically overestimates duration and underestimates frequency. Whole-interval sampling systematically underestimates both duration and frequency. This paper presents a post hoc method through which the systematic errors in duration estimates in partial-interval sampling and whole-interval sampling can be minimized. 相似文献