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991.
When a line is flashed instantaneously between two markers it can appear to propagate from one marker to the other. This illusion is known as the line motion effect. We investigated this effect in the two hemispheres of a callosotomy ("split-brain") patient. We found that both hemispheres perceived the line motion effect, and that flashing one of the markers biased the direction of motion away from that marker regardless of which hemisphere received the stimulus. In contrast, matching the width of the line to the width of one of the markers biased the direction of motion away from the marker only when it appeared in the left visual hemifield. This suggests that multiple mechanisms can contribute to the line motion effect, and that some of these mechanisms rely on different neural structures. 相似文献
992.
Walker MU 《Ethics & behavior》2002,12(3):279-80, 291-3
993.
Marcy C. Speer David S. Enterline Lorraine Mehltretter Preston Hammock Judith Joseph Margaret Dickerson Richard G. Ellenbogen Thomas H. Milhorat Michael A. Hauser Timothy M. George 《Journal of genetic counseling》2003,12(4):297-311
Chiari type I malformation has traditionally been defined as a downward herniation of the cerebellar tonsils of 5 mm through the foramen magnum and it is likely associated with a volumetrically reduced posterior fossa. Syringomyelia is commonly associated with Chiari type I malformation. We estimate the prevalence of these two conditions and determine that they are more common than previously expected. We identify the genetic syndromes associated with some cases of Chiari type I malformation, and we provide evidence in favor of a genetic hypothesis for at least a subset of the nonsyndromic cases. 相似文献
994.
Booth MZ 《Adolescence》2003,38(150):221-237
The developmental period of adolescence is explored in Swaziland from a multidisciplinary perspective. The study compares early anthropological research with contemporary interviews of Swazi parents. While the Swazi language, siSwati, does not have a term for "adolescent," there is evidence of a definite developmental period which could be defined as adolescence. Parents view this period as being qualitatively different from childhood and adulthood, but they also have gender-related interpretations of its nature and length. While biological maturation (especially menarche for females) is viewed as a vital step in becoming an adult, behaviors must be learned during this time (i.e., "adolescence") before one is completely of adult status. 相似文献
995.
This research questioned the proposition that corporate familiarity is positively associated with firm reputation. Student images of familiar and unfamiliar Fortune 500 corporations were examined in 4 experiments. The results suggested that, consistent with behavioral decision theory and attitude theory, highly familiar corporations provide information that is more compatible with the tasks of both admiring and condemning than less familiar corporations. Furthermore, the judgment context may determine whether positive or negative judgments are reported about familiar companies. The notion that people can simultaneously hold contradictory images of well-known firms may help to explain the inconsistent findings on the relation between familiarity and reputation. 相似文献
996.
DeMartino RE Crosby AE EchoHawk M Litts DA Pearson J Reed GA West M 《Suicide & life-threatening behavior》2003,33(2):101-110
The federal government, largely through the U.S. Department of Health and Human Services (HHS), sponsors an array of science-based suicide prevention initiatives. This article details the prevention-related agendas and collaborative efforts of five operating divisions within the Department of Health and Human Services: the Substance Abuse and Mental Health Services Administration, National Institutes of Health, Centers for Disease Control and Prevention, Indian Health Service, and Health Resources and Services Administration. The article highlights HHS's activities and their link to the National Strategy for Suicide Prevention, the plan which will guide the nation's suicide prevention efforts for the next decade. 相似文献
997.
The aim of this study was to extend the understanding of Developmental Coordination Disorder (DCD) into adulthood. We recruited 19 adults aged between 18 and 65 who had received diagnoses of DCD or dyspraxia or who self-reported as having motor impairments consistent with a history of DCD, together with age- and gender-matched controls. Participants were given tests of manual dexterity, handwriting, construction, obstacle avoidance, dynamic balance, static balance, dual task performance, ball skills, reaction time, movement time and sequencing. As a group, adults with DCD performed more poorly than controls across all tasks. Slowness and variability of movement was a pervasive feature of their performance and many individuals had considerable problems with sequencing and with dual task performance. A discriminant function analysis conducted using six performance measures correctly classified participants as car drivers or non-drivers. Adults do retain motor difficulties and these can exclude them from important activities of daily living. 相似文献
998.
We report the results of a 4-year-long study of capuchin monkeys (Cebus apella ) on concurrent three-way classification and linear size seriation tasks using explicit ordering procedures, requiring subjects
to select icons displayed on touch screens rather than manipulate and sort actual objects into groups. The results indicate
that C. apella is competent to classify nine items concurrently, first into three disjoint classes where class exemplars are identical to
one another, then into three reciprocal classes which share common exemplar (size) features. In the final phase we compare
the relative efficiency of executive control under conditions where both hierarchical and/or linear organization can be utilized.
Whilst this shows a superiority of categorical based size seriation for a nine item test set suggesting an adaptive advantage
for hierarchical over linear organization, Cebus nevertheless achieved high levels of principled linear size seriation with sequence lengths not normally achieved by children
below the age of six years. 相似文献
999.
Keil A Gruber T Müller MM Moratti S Stolarova M Bradley MM Lang PJ 《Cognitive, affective & behavioral neuroscience》2003,3(3):195-206
Allocation of processing resources to emotional picture stimuli was examined using steady-state visual evoked brain potentials (ssVEPs). Participants viewed a set of 60 colored affective pictures from the International Affective Picture System, presented in a flickering mode at 10 Hz in order to elicit ssVEPs. Phase and amplitude of the 10-Hz ssVEP were examined for six picture categories: threat and mutilation (unpleasant), families and erotica (pleasant), and household objects and persons (neutral). Self-reported affective arousal and hedonic valence of the picture stimuli were assessed by means of subjective ratings. Viewing affectively arousing (unpleasant and pleasant) pictures was associated with enhanced ssVEP amplitude at parieto-occipital recording sites, as compared with neutral stimuli. Phase information suggested increased coactivation of right occipitotemporal and frontotemporal sources during processing of affectively arousing stimuli. These findings are consistent with reentrant modulation of early visual processing by distributed networks including subcortical and neocortical structures according to a stimulus's motivational relevance. 相似文献
1000.
Two experiments examined how different frustration contexts affect the instrumental and emotional responses of 4- to 5-month-old infants. Three different frustrating contexts were investigated: loss of stimulation (extinction), reduction in contingent stimulation (partial reinforcement), and loss of stimulus control (noncontingency). In both experiments, changes in arm activity and facial expressions of anger and sadness coded according to the Maximally Discriminative Facial Movement Coding System (MAX) were the measures of frustration. Both experiments showed that (a) arm responses increased when the contingent stimulus was lost or reduced but decreased when control of the stimulus was lost under noncontingency, (b) MAX-coded anger, but not MAX-coded sad or blends of anger and sad, was associated with frustration, and (c) the pattern of anger and arm responses varied with the frustration context. When contingent stimulation was lost or reduced, both anger and arm responses increased, but when expected control was lost under noncontingency, arm responses decreased while anger increased. 相似文献