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931.
We were a group of Christian friends searching for affirmations that lay at the heart of our faith and reached to the limits of our existence and moral authority. As we have reflected on our role in deciding whether and to what extent we could assist in allowing our terminally ill friend, seventy-nine-year-old, Norman to die, we were deeply troubled by the moral ambiguity of our involvement. Through a careful process of authority through communal discernment, our responsibility for Norman became clear: we were to assist him in living the life he embraced in baptism -- a life which included a destiny that was conformed to the crucified and risen one. That was not the destiny we chose for Norman; it was the destiny he owned. We recognized with Norman that our lives are not our own to be guided by autonomy and liberty, but rather to be lived for the glory of Jesus the Christ.  相似文献   
932.
College students periodically experience many challenges in pursuit of their educational goals. Such experiences can have deleterious effects on subsequent motivation and performance when they are perceived as negative. Research shows that some students who experience negative events are buffered against motivational deficits, whereas others are motivationally at-risk. Several individual difference variables have been proposed to account for such diverse reactions. A longitudinal field study that involved three phases was conducted to extend this research. Phase I examined the motivational buffering effects of academic attributional style on students' performance, motivation, and emotions. Results indicated that attributional style related to students' performance, motivation, and emotions. Specifically, students who routinely made unstable and controllable attributions for negative academic events exhibited the greatest performance and motivation compared to students who typically made stable and uncontrollable attributions. Phases II and III were designed to examine the remedial benefits of attributional retraining for different attributional styles. Findings indicated that attributional retraining influenced motivation, emotions, and course grade. These results were qualified by the interaction between attributional style, attributional retraining, and time. Findings are discussed within Weiner's (1985, 1986) attribution theory. This research was based, in part, on the first author's dissertation submitted to the Department of Psychology and the Faculty of Graduate Studies of The University of Manitoba in partial fulfillment for the Degree of Doctor of Philosophy. This research was supported by a Social Sciences and Humanities Research Council of Canada (SSHRCC) doctoral fellowship, a University of Manitoba doctoral fellowship, and a SSHRCC postdoctoral fellowship to the first author. In addition, the research was also supported by a SSHRCC research grant (#410911296) to the second author. The authors gratefully acknowledge the helpful comments of Bernard Weiner, Harvey Keselman, John Adair, Rodney Clifton, and Robert Altemeyer. Also appreciated was the assistance of Verena Menec and the Higher Education Research group.  相似文献   
933.
934.
Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.  相似文献   
935.
936.
The φ-maze is a novel implementation of the T-maze that can be used for various behavioral experiments. It consists of a start/goalbox from which a central alley leads to a choice point. Left and right arms return to the start/goalbox, where reinforcers are delivered. A holding chamber at the choice point can be used for delayed (non)matching-to-sample experiments. Lamps mounted under the translucent acrylic floor serve as visual stimuli. The design incorporates reliable and inexpensive automated guillotine doors and a modification of a commercially available pellet dispenser that allows the automated dispensing of Froot Loop reinforcers. The φ-maze has been used successfully in experiments involving spatial and visual alternation, visual discrimination, and delayed matching-to-sample.  相似文献   
937.
Ten subjects served as their own controls in two conditions of continuous, centrifugally produced hypergravity (+2 Gz) and a 1-G control condition. Before and after exposure, open-loop measures were obtained of (1) motor control, (2) visual localization, and (3) hand-eye coordination. During exposure in the visual feedback/hypergravity condition, subjects received terminal visual error-corrective feedback from their target pointing, and in the no-visual feedback/hypergravity condition they pointed open loop. As expected, the motor control measures for both experimental conditions revealed very short lived underreaching (the muscle-loading effect) at the outset of hypergravity and an equally transient negative aftereffect on returning to 1 G. The substantial (approximately 17°) initial elevator illusion experienced in both hypergravity conditions declined over the course of the exposure period, whether or not visual feedback was provided. This effect was tentatively attributed to habituation of the otoliths. Visual feedback produced a smaller additional decrement and a postexposure negative aftereffect, possible evidence for visual recalibration. Surprisingly, the target-pointing error made during hypergravity in the no-visual-feedback condition was substantially less than that predicted by subjects’ elevator illusion. This finding calls into question the neural outflow model as a complete explanation of this illusion.  相似文献   
938.
A comprehensive four-factor interactive model on physical, psychological, and environmental processes related to the sense of control is presented for adult development with an emphasis on later life. The four experienced components are (1) control from within oneself, (2) control over oneself, (3) control over the environment, and (4) control from the environment. Control over oneself and over the environment measure self-directed control, while control from within oneself and from the environment measure nonself-directed control. Coping (a bidimensional control scale) measures control from powerlessness and suicide to overcontrolling. Findings confirm a significant loss of coping in an older cohort group from a white, rural sample composed primarily of single subjects with low coping representing a significant drop in self-directed behavior. A discussion of the relationship between self-direction and health in the older cohort group follows.  相似文献   
939.
New York State's initial attempt at individualizing services occurred within the context of an experiment. We randomly assigned children 5–12 years old who were referred for out-of-home placement in treatment foster care to either treatment foster care, Family-Based Treatment (n=15), or to Family-Centered Intensive Case Management (FCICM) (n=27). FCICM used teams of case managers and parent advocates to provide in-home services. Flexible service dollars, respite care, and behavior management skills training were available to assist teams in individualizing care. Preliminary outcomes indicate that children in FCICM are doing as well or better than children assigned to FBT in their functioning and symptom reduction. Parents of children in FCICM have made gains, although not at a statistically significant level, in behavior management skills and family strengths that allow them to provide care for their children at home.  相似文献   
940.
Most speech research with infants occurs in quiet laboratory rooms with no outside distractions. However, in the real world, speech directed to infants often occurs in the presence of other competing acoustic signals. To learn language, infants need to attend to their caregiver’s speech even under less than ideal listening conditions. We examined 7.5-month-old infants’ abilities to selectively attend to a female talker’s voice when a male voice was talking simultaneously. In three experiments, infants heard a target voice repeating isolated words while a distractor voice spoke fluently at one of three different intensities. Subsequently, infants heard passages produced by the target voice containing either the familiar words or novel words. Infants listened longer to the familiar words when the target voice was 10 dB or 5 dB more intense than the distractor, but not when the two voices were equally intense. In a fourth experiment, the assignment of words and passages to the familiarization and testing phases was reversed so that the passages and distractors were presented simultaneously during familiarization, and the infants were tested on the familiar and unfamiliar isolated words. During familiarization, the passages were 10 dB more intense than the distractors. The results suggest that this may be at the limits of what infants at this age can do in separating two different streams of speech. In conclusion, infants have some capacity to extract information from speech even in the face of a competing acoustic voice.  相似文献   
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