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111.
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It is increasingly important for government agencies to collaborate across jurisdictional and functional boundaries. Interorganizational systems supporting interagency collaboration must accommodate a wide range of factors from the external environment and participating organizations as part of their design and operation. This paper presents the findings from a case study of CapWIN, a collaborative network created to enable first responders to share information across jurisdictional and functional boundaries as they work together during emergencies and other critical events. The study examines how aspects of the external environment and the agency context impeded or facilitated the CapWIN collaborative network and the interorganizational system (IOS) that supports it. We identify factors affecting information sharing and collaborative processes, and describe how these factors interact to enable and constrain an IOS. The paper concludes with suggestions for further research on the interplay of environmental, organizational, and technical aspects of interagency collaboration networks as they evolve over time.  相似文献   
113.
宽容的艺术     
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This review highlights two areas of particular interest in the study of social learning in fowl. First, the role of social learning in the development of feeding and foraging behavior in young chicks and older birds is described. The role of the hen as a demonstrator and possible teacher is considered, and the subsequent social influence of brood mates and other companions on food avoidance and food preference learning is discussed. Second, the way in which work on domestic fowl has contributed to an understanding of the importance of directed social learning is examined. The well-characterized hierarchical social organization of small chicken flocks has been used to design studies which demonstrate that the probability of social transmission is strongly influenced by social relationships between birds. The practical implications of understanding the role of social learning in the spread of injurious behaviors in this economically important species are briefly considered.  相似文献   
116.
Halverson, Roberton, and Langendorfer (1982) reported the development of children ages 6-13 years filmed longitudinally performing the forceful overarm throw. These authors described the children's progress through developmental sequences for trunk, humerus, and forearm actions; however, they did not study developmental relationships ("profiles") across these components. This paper reports how the profiles changed in the same children across trials within filming sessions and over time. The data revealed both common and individual developmental pathways. The frequencies of some pathways were not chance occurrences (p < or = .01), suggesting that within-person constraints eliminated certain movement relationships while encouraging others. The authors hypothesize that the kinematics of trunk rotation may serve as a control parameter for pattern change.  相似文献   
117.
The aim of this study was to compare the pre- and post-impact three-dimensional kinematics of the ball and racquet during first and second serves performed by elite tennis players. Data were collected from four male and four female right-handed professional players during competition using two high-speed cameras (200 Hz). For each player, one first serve and one second serve from the 'deuce' or right service court that landed within the specified target area were analysed. To test for significant differences between the first and second serves, Wilcoxon tests (P < or = 0.05) were performed on selected parameters. The results indicate that the ball travelled forward and to the left during the flight phase of the toss in all but one trial. The average pre-impact ball forward location for the first serve was significantly more in front and had a higher associated forward ball velocity than the corresponding values for the second serve. On average, the decrease in post-impact ball speed from the first to the second serve was 24.1%. No significant differences between the first and second serves were found in the pre-impact racquet head speed and orientation, which was represented as a unit vector perpendicular to the racquet face. The major adjustments made by the players when going from the first to second serve were a decrease in pre-impact ball forward location (P < or = 0.01) and an increase in the pre-impact racquet vertical and lateral velocities (both P < or = 0.05). This implies that the players tossed the ball closer to the body and imparted topspin and sidespin on the ball by changing the racquet vertical and lateral velocities when going from the first to the second serve.  相似文献   
118.
The aim of this study was to assess the effect of to isometic contraction durations during propiceptive neuromuscular facilitation stretching on gains inflexion at the hip. Forty-three women (M age = 20.0 years, SD = 1.3) were assigned to one of three groups: 5-s isometric contraction (5-IC), 10-IC, and control. Flexibility was assessed at baseline and Weeks 3 and 6. Analysis of covariance, controlling for pretest differences, showed a significant interaction, F(2, 33) = 44.1, p < .001. Flexibility was significant lower in the control group relative to the 5-IC and 10-IC groups and in the 5-IC group relative to the 10-IC group at 3 and 6 weeks (3 weeks = 101.2 +/- 1.4 degrees, 114.3 +/- 1.5 degrees, 120.5 +/- 1.3 degrees; 6 weeks = 103.0 +/- 1.4 degrees, 126.1 +/- 1.6 degrees, 133.3 +/- 1.4 degrees for control, 5-IC and 10-IC groups, respectively). A longer contraction time led to greater increases in flexibility.  相似文献   
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Children with learning disabilities in four types of special education settings were compared in terms of social acceptance, number of friends, quality of relationship with best friends, self‐concept, loneliness, depression, social skills, and problem behaviors. Two of the placements (In‐Class Support and Resource Room) were for children with mild to moderate learning disabilities and involved between 30 and 90 minutes of special education per school day. The other two placements (Inclusion Class and Self‐Contained Special Education Class) were designated for children with severe learning disabilities and involved at least a half‐day of special education. Children in the more inclusive placements had more positive social and emotional functioning. Children receiving In‐Class Support were more accepted by peers, had higher self‐perceptions of mathematics competence, and fewer problem behaviors than children receiving Resource Room Support. Children in Inclusion Classes had more satisfying relationships with their best school friends, were less lonely, and had fewer problem behaviors than children in Self‐Contained Special Education Classes.  相似文献   
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