全文获取类型
收费全文 | 24325篇 |
免费 | 1595篇 |
国内免费 | 43篇 |
出版年
2018年 | 325篇 |
2017年 | 372篇 |
2016年 | 369篇 |
2015年 | 237篇 |
2014年 | 309篇 |
2013年 | 1787篇 |
2012年 | 622篇 |
2011年 | 700篇 |
2010年 | 492篇 |
2009年 | 546篇 |
2008年 | 622篇 |
2007年 | 630篇 |
2006年 | 539篇 |
2005年 | 505篇 |
2004年 | 515篇 |
2003年 | 478篇 |
2002年 | 501篇 |
2001年 | 839篇 |
2000年 | 787篇 |
1999年 | 633篇 |
1998年 | 326篇 |
1997年 | 263篇 |
1996年 | 280篇 |
1994年 | 258篇 |
1993年 | 261篇 |
1992年 | 525篇 |
1991年 | 495篇 |
1990年 | 513篇 |
1989年 | 483篇 |
1988年 | 446篇 |
1987年 | 443篇 |
1986年 | 440篇 |
1985年 | 450篇 |
1984年 | 360篇 |
1983年 | 312篇 |
1982年 | 269篇 |
1979年 | 405篇 |
1978年 | 293篇 |
1977年 | 264篇 |
1976年 | 241篇 |
1975年 | 355篇 |
1974年 | 389篇 |
1973年 | 378篇 |
1972年 | 372篇 |
1971年 | 328篇 |
1970年 | 287篇 |
1969年 | 344篇 |
1968年 | 407篇 |
1967年 | 359篇 |
1966年 | 368篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Donald G. York 《Zygon》1995,30(3):477-478
Abstract. Frank Tipler's The Physics of Immortality provides abundant cause for intellectual offense—including challenges to physics, to theology, and, seemingly, to common sense. Few philosophical conundrums remain unaddressed. Still, the book is stimulating and well presented. 相似文献
992.
Preventing antisocial behavior in the schools 总被引:1,自引:0,他引:1
Mayer GR 《Journal of applied behavior analysis》1995,28(4):467-478
Multiple correlates and determinants of antisocial behavior within the home, community, and school are reviewed. Due to the school's pivotal role in our society, an emphasis is placed on how our schools contribute to antisocial behavior, and what educators can do to prevent anti-social behavior and related attendance problems. A variety of contextual factors and setting events within our schools appear to be major contributors to antisocial behavior, and some of the same factors identified within the schools also have been identified within the home. These setting events, rather than quick restrictive fixes, must be given more attention if we are to provide safe school environments-environments that durably prevent antisocial behavior and related attendance problems. 相似文献
993.
Effects of a variable-ratio conditioning history on sensitivity to fixed-interval contingencies in rats. 总被引:7,自引:7,他引:0
下载免费PDF全文
![点击此处可从《Journal of the experimental analysis of behavior》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We investigated the possibility that human-like fixed-interval performances would appear in rats given a variable-ratio history (Wanchisen, Tatham, & Mooney, 1989). Nine rats were trained under single or compound variable-ratio schedules and then under a fixed-interval 30-s schedule. The histories produced high fixed-interval rates that declined slowly over 90 sessions; differences as a function of the particular history were absent. Nine control animals given only fixed-interval training responded at lower levels initially, but rates increased with training. Despite differences in absolute rates, rates within the intervals and postreinforcement pauses indicated equivalent development of the accelerated response patterns suggestive of sensitivity to fixed-interval contingencies. The finding that the histories elevated rates without retarding development of differentiated patterns suggests that the effective response unit was a burst of several lever presses and that the fixed-interval contingencies acted on these units in the same way as for single responses. Regardless of history, the rats did not manifest the persistent, undifferentiated responding reported for humans under comparable schedules. We concluded that the shortcomings of animal models of human fixed-interval performances cannot be easily remedied by including a variable-ratio conditioning history within the model. 相似文献
994.
This study examines differential prediction of WIAT achievement scores based on WISC-III FSIQ in white as compared with African American and Hispanic children, and in females as compared with males. A procedure which allows simultaneous comparisons of slopes and intercepts across groups is employed. The results are consistent with previous research findings in supporting the general absence of bias in predicting achievement from IQ. 相似文献
995.
Rats were trained on concurrent schedules under which responses on one lever postponed shock (avoidance) and responses on the other lever produced brief (2-min) periods of signaled timeout from avoidance. For 6 rats, timeout from avoidance was programmed on a variable-interval 45-s schedule that generally resulted in rates that were lower than those on the avoidance lever. For another 6 rats, timeout was arranged on a variable-ratio 15 schedule that produced higher baseline rates. Cocaine (3 to 40 mg/kg) produced large, dose-dependent increases in behavior maintained by timeout in both groups of rats. Avoidance responding was also generally increased by cocaine, but the increases were of lesser magnitude. Increases in response rates were seen across a broad range of doses on behavior maintained by either interval or ratio schedules, an outcome that was unexpected on the basis of most studies of cocaine on food-maintained behavior. These results were similar to those of previous studies of the effects of amphetamine on behavior maintained by timeout from avoidance and suggest that stimulant drugs affect behavior maintained under a shock-postponement schedule differently than they affect behavior maintained by timeout from avoidance. 相似文献
996.
Morgan WG 《Journal of personality assessment》1995,65(2):237-254
The origin and history of each of the images appearing on the 1943/1971 edition of the Thematic Apperception Test is presented. This information corrects and supplements that provided by Murray (1943/1971) in the test manual. Authorship of the test, including the contributions of Christiana Morgan, is discussed. The material presented expands the historical record and may serve as an aid in test interpretation. 相似文献
997.
In the behavioral theory of timing, pacemaker rate is determined by overall rate of reinforcement. A two-alternative free-operant psychophysical procedure was employed to investigate whether pacemaker period was also sensitive to the differential rate of reinforcement. Responding on a left key during the first 25 s and on a right key during the second 25 s of a 50-s trial was reinforced at variable intervals, and variable-interval schedule values during the two halves of the trials were varied systematically. Responding on the right key during the first 25 s and on the left key during the second 25 s was not reinforced. Estimates of pacemaker period were derived from fits of a function predicted by the behavioral theory of timing to right-key response proportions in consecutive 5-s bins of the 50-s trial. Estimates of pacemaker period were shortest when the differential reinforcer rate most strongly favored right-key responses, and were longest when the differential reinforcer rate most strongly favored left-key responses. The results were consistent with the conclusion that pacemaker rate is influenced by relative reinforcer rate. 相似文献
998.
Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general. 相似文献
999.
Rev. Bruce G. Epperly Ph.D. 《Journal of religion and health》1995,34(2):141-148
Recent medical studies documenting the influence of prayer in our physical lives challenge mainstream Christians to rethink their ideas and practice of prayer. A new model of prayer questions dysfunctional images of prayer based on 1) the doctrine of divine omnipotence, 2) the rewards-punishments notion of health and illness, and 3) linear notions of the power of prayer. Relational, holistic, and multidimensional images of God, human existence, and the effects of prayer provide the basis for a constructive theology of prayer. Ironically, the fact that prayer is not omnipotent makes it possible to practice prayer in a technological context. 相似文献
1000.
The focus of the present study was on the intersegmental relationships that emerge when both task and oganismic constraints are imposed upon the coordination system. Seven right-handed subjects were required to reach and grasp a cup (hand transport phase) and place it on a designated target (cup transport phase), using either their preferred or nonpreferred hand. The kinematics of the movement were examined as a function of task (grasping a full cup versus grasping an empty one) and organismic (preferred or nonpreferred hand) constraints. During the hand transport phase, a task constraint effect was revealed through an increase in the low-velocity phase for the full cup condition. This constraint coexisted with a decrease in angular motion of the shoulder and elbow joints, indicating subjects reduced the number of variables to be independently controlled in the final homing-in stage of the movement. Accompanying this decrease in angular change was an increase in the displacement of the trunk. During the cup transport phase, the trunk was shown to contribute significantly more to the movement in the full cup condition and for the left hand movements, thereby increasing the stability of the movement system. These findings are in agreement with Bernstein's (1967) notion of fixating parts of the body as an initial solution to a movement problem, and they lend support to the concept of a proximodistal organization of coordination. 相似文献