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971.
Memory & Cognition - The use of different types of partial temporal information is shown to affect dating accuracy and the distribution of errors in event dating. Several different types of...  相似文献   
972.
Summary A study of movement disorders such as Parkinson's disease and Huntington's disease can provide an indication of the motor functions of the basal ganglia. Basal-ganglia diseases affect voluntary movement and can cause involuntary movement. Deficits are often manifested during the coordination of fine multi-joint movements (e. g., handwriting). The disturbances of motor control (e.g. akinesia, bradykinesia) caused by basal-ganglia disorders are illustrated. Data suggest that the basal ganglia play an important role in the automatic execution of serially ordered complex movements.  相似文献   
973.
974.
The relationship between parental self-esteem and behavior problems in children was investigated using 1624 married couple's responses from the National Survey of Families and Households. The sample was weighted to be nationally representative in terms of race and ethnicity. It was hypothesized that the existence of behavior problems among children would be associated with low self-esteem among parents and that the parent's gender, child's gender, parents' gender role attitudes, and parental employment would moderate this relationship. The results indicated that parental self-esteem is negatively associated with behavior problems in children. However, none of the moderating variables had a significant impact. This suggests that the relationship between parental self-esteem and behavior problems among children is robust and does not vary appreciably with the gender of the parent, the gender of the child, the attitudes of the parent, or the employment of the parent.  相似文献   
975.
Dona L. Davis 《Sex roles》1993,29(7-8):457-475
In the traditional Newfoundland maritime division of labor, men worked at sea on boats and women worked on the land in their households. Patterns of gender identity, work, and gender relations were characterized by an ethos of complementarity. Present declines in the fishery make it impossible to earn a living at sea and men have become landbound. The resulting infringement by unemployed men into the spaces and prerogatives traditionally allotted to women has come to generate a gender antagonism that permeates, if not dominates, contemporary gender relations in a southwest coast Newfoundland fishing community. Ethnographic analysis incorporates data collected during two periods of anthropological fieldwork: 1977–1978 and 1989–1990. Comparative assessment of economic, psychological, and cultural constructionist theories of gender relations inform the qualitative analysis of ethnographic data.The original period (1977–1978) of anthropological fieldwork was funded by a grant from the United States National Institute of Child and Maternal Health, which was administered through the Population Center at the University of North Carolina, Chapel Hill. The second period (1989–1990) of fieldwork was funded by grants from Memorial University of Newfoundland's Institute of Social and Economic Research, the Canadian Embassy's Canadian Studies Program, and the University of South Dakota's General Research Fund.  相似文献   
976.
In discussions of process models of human information processing, the continuous flow conception (Eriksen and Schultz 1979) plays a prominent role. A central prediction of this conception is that any information in a display associated with a response activates that response as soon as it becomes available in the perceptual system. If it concerns the correct response channel, then response facilitation occurs. If it concerns the incorrect response channel, then response competition occurs. To assess these mechanisms more directly, we used psychophysiological measures as well as reaction time (RT). We used the latency of the P3 component of the event related brain potential (ERP) as an index of stimulus evaluation duration, the onset of lateralized motor activity derived from the ERP as an index of selective central motor activation, and the onset of electromyographic activity as an index of the start of peripheral motor activation. Subjects were required to respond to target letters that were either flanked by letters that signalled the opposite response (incompatible arrays), by the target itself (compatible arrays), by letters not associated with a response (neutral arrays), or by no other letters (targets alone). Our results replicated the basic findings obtained in this paradigm. RTs to targets alone did not differ from RTs to compatible arrays. The latter were faster than RTs to neutral arrays, which were faster than RTs to incompatible arrays. P3 latencies were longer on incompatible than on neutral trials, and longer on compatible than on target alone trials. Incorrect central response activation on incompatible trials and correct central response activation on compatible trials, both began earlier than on target alone trials. Peripheral responding on both trial types, however, began later than on target alone trials. More incompatible but less compatible trials than neutral ones exhibited incorrect peripheral response activation. Peripheral response execution was faster and more accurate on compatible than on target alone trials, while it was slower and less accurate on incompatible than on neutral trials. These results indicate, that the flankers activated their associated response channel while display evaluation was still going on, and that response facilitation and competition occurred. After applying criteria proposed by Miller (1988), it was concluded that the set of stimulus recognition processes and the set of response activation processes cannot be regarded as independent stages of processing.  相似文献   
977.
W D Watts  L S Wright 《Adolescence》1990,25(97):171-181
This study examined the relationship between drug use and delinquent behavior among 348 high school males (154 whites, 172 Mexican-Americans, and 22 blacks) and 89 adjudicated delinquent males confined to a maximum-security facility for violent and repeat offenders (37 whites, 25 Mexican-Americans, and 27 blacks). Data were collected in the spring of 1986 using self-administered questionnaires. Analyses were performed separately for each racial subgroup. Simple correlations revealed that self-reported alcohol, tobacco, marijuana, and other illegal drug use were all significantly related to both minor and violent delinquency for all three racial groups. Multiple regression analysis revealed that the use of these substances accounted for 40% to 47% of the variance in minor delinquency and for 59% of the variance in violent delinquency among blacks, 53% of the variance in violent delinquency among Mexican-Americans, and 34% of the variance in violent delinquency among whites. The best predictors of violent delinquency were the frequent use of illegal drugs other than marijuana and use of tobacco, in that order, among Mexican-Americans; the frequent use of other illegal drugs, marijuana, and tobacco, in that order, for whites; and the frequent use of illegal drugs, followed by marijuana, for blacks.  相似文献   
978.
The parenting attitudes of adolescent and older mothers were assessed at 1 and 12 months postpartum to explore group differences and determine if these attitudes predicted quality of home environment and parenting behaviors at 12 months. Adolescent mothers scored significantly lower than did older mothers in empathy toward children's needs, but there were no significant group differences on three other parenting attitude constructs. There were no significant correlations between parenting attitudes at 1 month and parenting behaviors at 12 months for either group. For adolescent mothers at 12 months postpartum, the only attitude construct that was significantly related to concurrent quality of parenting was developmental expectations of the child. These and other findings are discussed in the context of current theory and intervention related to adolescent parenting.  相似文献   
979.
980.
The size of the perceptual unit used in reading was addressed using the predesignated target paradigm. Sixteen subjects viewed the following stimuli in random order: the words tee, the, tie, and toe; the nonwords eet, eht, eit, and eot; and the letters e, h, i, and o. Subjects fixated on the location of the center letter and identified the letter as e, h, i, or o, alternatives which were known to them at the onset. A word superiority effect was obtained for the common word the but not for the less common words tee, tie, and toe. The word superiority effect was attributable to bias rather than discriminability: Subjects exhibited a bias to perceive the words in this experiment as the (i.e., there was a bias to perceive h in the t e stimulus presentations). These results suggest that the common word the is processed in reading units that are larger than the letter, and that the system is biased to perceive common rather than uncommon words in data-limited conditions.  相似文献   
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