全文获取类型
收费全文 | 24991篇 |
免费 | 915篇 |
国内免费 | 9篇 |
出版年
2018年 | 335篇 |
2017年 | 359篇 |
2016年 | 364篇 |
2015年 | 262篇 |
2014年 | 338篇 |
2013年 | 1777篇 |
2012年 | 590篇 |
2011年 | 636篇 |
2010年 | 439篇 |
2009年 | 394篇 |
2008年 | 624篇 |
2007年 | 554篇 |
2006年 | 530篇 |
2005年 | 458篇 |
2004年 | 460篇 |
2003年 | 465篇 |
2002年 | 478篇 |
2001年 | 636篇 |
2000年 | 649篇 |
1999年 | 524篇 |
1998年 | 270篇 |
1997年 | 285篇 |
1996年 | 280篇 |
1995年 | 269篇 |
1992年 | 505篇 |
1991年 | 463篇 |
1990年 | 445篇 |
1989年 | 418篇 |
1988年 | 438篇 |
1987年 | 410篇 |
1986年 | 453篇 |
1985年 | 431篇 |
1984年 | 376篇 |
1983年 | 334篇 |
1981年 | 269篇 |
1979年 | 403篇 |
1978年 | 332篇 |
1977年 | 286篇 |
1976年 | 298篇 |
1975年 | 338篇 |
1974年 | 430篇 |
1973年 | 469篇 |
1972年 | 346篇 |
1971年 | 370篇 |
1970年 | 337篇 |
1969年 | 365篇 |
1968年 | 439篇 |
1967年 | 407篇 |
1966年 | 419篇 |
1958年 | 253篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
The validity of maternal self-reports about their parenting behaviour is evaluated with two studies. In both studies, the mothers were observed shopping in the supermarket with their 2-year-old children. One week later they responded to multiple choice questions on a computer that simulated the experience of shopping with their children. The exact agreement between the two types of data was then assessed. The results from the first study involving 28 mothers revealed some agreement, although it was generally low. In an effort to increase the level of agreement, the computer simulation was revised to allow multiple responses and to clarify some of the simulation vigenettes. A replication study resulted in a considerably higher level of agreement for 22 mothers. Implications of this method for researchers and practitioners are discussed. 相似文献
222.
A structural analysis of the problem behaviors of 32 adults with mental retardation living together in a residential facility showed that a disproportionate number of these behaviors were associated with a period of time scheduled for leisure activities. A staff management program was implemented during this time which included activity and staff scheduling, staff inservice training, and staff performance monitoring and feedback. The results showed an 83% decrease in problem behaviors when the program was implemented during the leisure period and no decrease in problem behaviors during adjacent time periods where the program was not utilized. Follow-up assessments indicated maintenance of these decreased levels of behavior at 3 and 6 months. It was concluded that this approach of combining a structural analysis with staff management procedures was effective in reducing a high level of problem behavior in a residential setting. The results are discussed with regard to pragmatic strategies for the pretreatment analysis of problem behaviors in residential settings, and the role of organizational behavior management techniques in habilitative programing for individuals with behavior disorders. 相似文献
223.
Chloee K. Poag Ph.D. Robert Cohen Ph.D. Scott W. Henggeler Ph.D. Mary B. Summerville Ph.D. Glen E. Ray M.S. 《Journal of child and family studies》1992,1(3):287-303
The purpose of this research was to examine the relationship between parents' perceptions of marital satisfaction and family stress and their third grade children's classroom behavior. Twenty-one married couples completed questionnaires during home visits. Behavior observations were made from videotapes of children recorded in their classroom during lunch and group academic periods on each of three days. Frequencies of peer interactions, solitary behaviors, and teacher interactions were coded. Regression analyses showed that mothers' level of marital satisfaction (but not fathers') predicted their children's frequency of peer interactions during lunch. Fathers' level of perceived family stress (but not mothers') predicted their children's frequency of peer interactions during lunch. Neither measure for either parent was related to the frequency of peer interactions, solitary behaviors, or teacher interactions observed during the academic sessions. These findings highlight the importance of assessing the potential differential relation of parent variables to children's trans-situational behaviors, and the examination of these variables in relation to different social-environmental contexts in which children participate outside the home. 相似文献
224.
Mary I. Armstrong M.S.W. M.B.A. Mary E. Evans Ph.D. 《Journal of child and family studies》1992,1(1):61-74
Systems of care for children with serious emotional disturbance and their families have generally lacked intensive community-based programs. We describe three types of newly established community-based programs in New York State and present a general evaluation plan for determining which programs work for various children and their families. The three community-based programs are Intensive Case Management, Family-Based Treatment, and Family-Centered Intensive Case Management. Process and outcome evaluations are being conducted for each of these programs. These evaluations make use of common intake and termination instruments, based on a minimum data set, standardized assessment instruments, and a common logic model, thus facilitating the comparison of findings across evaluations. 相似文献
225.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more. 相似文献
226.
Stephen W. Kohlmeyer 《Behavior research methods》1992,24(1):67-71
Picture Perception Lab (PPL) is a program for picture perception experiments. PPL capitalizes on the sophisticated drawing software available for the Macintosh computer by allowing the user to create stimulus images by using almost any drawing package. Through a series of user-friendly dialog boxes, PPL enables even nonprogrammers to develop, quickly and easily, tachistoscopelike vision experiments. The program allows a wide variety of experimental designs. Image exposure durations and subjects’ reaction times are precisely monitored with millisecond timing functions. Each image is drawn on the screen in a single 60-Hz refresh. 相似文献
227.
Robert W. Allan 《Behavior research methods》1992,24(2):150-156
Pigeons’ pecking has long been a subject of interest in behavioral research, with the response typically being viewed as unitary. Recent experiments done with computer-controlled devices have revealed that this response is at least bipartite in character, with beak opening and response location (head transport) as its components. In addition, experimental work has demonstrated that these response components may be separately influenced and controlled by respondent and operant conditioning procedures. The detailed topographic analysis and technology that have emerged may provide a background for similar work with other behavioral systems. 相似文献
228.
Utrecht Biophysics Research Institute, Rijksuniversiteit Utrecht, Utrecht, The Netherlands Subjects were asked to match the speeds of two moving random-dot patterns seen through circular apertures. The speed of one pattern that moved horizontally toward the right of a computer screen changed continuously. The speed of this pattern represented the target. It was to be matched with the speed of the second pattern, which moved in the opposite direction. The subject controlled the speed of the second pattern by means of an isometric joystick. The distance between the apertures on the screen as well as the subject’s distance from the screen served as experimental parameters. In this way, the effects of both spatialand temporal transients of pattern speed on human tracking performance were studied. To avoid anticipation by the subject, the amplitude and the frequency of the target pattern speed changed pseudorandomly. The accuracy with which the subject performed the matching task was influenced by the mean pattern speed and the parameters of the visual field. Within lower velocity ranges, the subject’s sensitivity to the instantaneous speed differences varied according to Weber’s law. The cross-correlation of the velocity time courses decreased when the mean speed of the target pattern was increased. Two stimulus parameters had a strong influence on the modulation of the correlation value: (1) the angular size of the stimulus on the retina and (2) the retinal eccentricity of the stimulus. 相似文献
229.
ACTH 4-9 analog can retard spatial alternation learning in brain damaged and normal rats 总被引:1,自引:0,他引:1
Thirty adult male hooded rats (Long-Evans strain) were assigned randomly to one of three lesion groups (n = 10) and prepared with medial frontal, posterior parietal, or sham neocortical injuries. Following a recovery interval of 10-12 days, access to water was limited to 30 min per day and the rats were shaped to traverse a T-maze for a reward of sweetened water. After a pretraining criterion was attained, osmotic minipumps (Alzet 2002) were installed subcutaneously. The minipumps delivered chronically for the next 14 to 15 days either 0 or 1.2 micrograms of ACTH 4-9 dissolved in bacteriostatic saline per day while the rats were trained on a reinforced spatial alternation task. Analysis of the number of errors made to a criterion of at least 80% correct alternations in two consecutive training sessions, or a ceiling of 62 errors (attained by two rats with parietal lesions), revealed that learning was impaired in the rats with parietal injuries. Contrary to our hypothesis, animals receiving ACTH 4-9 committed more errors than their counterparts receiving only saline. 相似文献
230.
Context effects in stroop-like word and picture processing 总被引:7,自引:0,他引:7
Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color-color, picture-picture, and word-word stimuli instead of the usual modally mixed color-word or picture-word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test. 相似文献