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891.
Our recent work suggests that infants begin to change their hand and joint kinematics in the presence of a toy months before the onset of purposeful reaching. Moreover, these 'toy-oriented' changes in hand kinematics cluster into Early, Mid and Late phases. The purpose of the present study was to test hypotheses regarding toy-oriented changes in joint kinematics in the same infants. METHODS: Thirteen infants were observed every other week from 8 weeks up to the first week of reaching around 20 weeks. At each session, a high-speed motion analysis system recorded infants' arm movements with and without a toy present. RESULTS: During the Early phase, infants scaled down their movements. In contrast, during the Mid phase infants scaled up their movements and did not change the relationship between the shoulder and elbow for speed and smoothness-related variables. In addition, infants showed toy-oriented changes such as increase in shoulder flexion and adduction. In the Late phase, infants continued to produce toy-oriented changes in shoulder orientation, and increased shoulder excursion and speed relative to the elbow. Thus, the toy-oriented changes in hand kinematics in the Mid and Late phases [Bhat, A. N., & Galloway, J. C. (2006). Toy-oriented changes in early arm movements of young infants: Hand kinematics. Infant Behavior and Development, 29(3), 358-372] more closely followed changes in shoulder kinematics. Lastly, results are discussed in terms of shoulder-elbow dissociations, speed-amplitude relationships, and the key role of spontaneous movements in the development of reaching. 相似文献
892.
Bar-Haim Y Lamy D Pergamin L Bakermans-Kranenburg MJ van IJzendoorn MH 《Psychological bulletin》2007,133(1):1-24
This meta-analysis of 172 studies (N = 2,263 anxious,N = 1,768 nonanxious) examined the boundary conditions of threat-related attentional biases in anxiety. Overall, the results show that the bias is reliably demonstrated with different experimental paradigms and under a variety of experimental conditions, but that it is only an effect size of d = 0.45. Although processes requiring conscious perception of threat contribute to the bias, a significant bias is also observed with stimuli outside awareness. The bias is of comparable magnitude across different types of anxious populations (individuals with different clinical disorders, high-anxious nonclinical individuals, anxious children and adults) and is not observed in nonanxious individuals. Empirical and clinical implications as well as future directions for research are discussed. 相似文献
893.
This study used 3 generations and 21 years of prospective data to test models of intergenerational transmission of substance use and substance use risk. Thus, the study extends prior studies in the field that have focused predominantly on substance abuse. The association between the grandparental generation's (G1 mother and father) and the parental generation's (G2 father) alcohol use and illicit drug use was hypothesized to be mediated by G2's poor inhibitory control. Additionally, G1's poor discipline of G2 was hypothesized to be directly associated with G2's substance use as well as to partially mediate the association between G1's substance use and G2's inhibitory control. In turn, G2's substance use in late adolescence was expected to be associated with its offspring's (G3) poor inhibitory control at age 3 years. Findings partially supported the predictions and varied by substance. For alcohol use, only cross-generational associations in use were found. For illicit drugs, both poor inhibitory control and poor discipline played some mediational role in cross-generational use. 相似文献
894.
Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are well recognized syndromes related to the rapid correction of hyponatremia, which are reported to show brain stem signs and various movement disorders. Cognitive dysfunction and neuropsychological findings, however, have seldom been reported. Cognitive manifestations in osmotic myelinolysis may have been underestimated due to the prominent brain stem symptoms and movement disorders. We report a case of EPM without CPM and describe the neuropsychological findings of EPM. The absence of CPM in this case made it possible to test neuropsychological function in the acute stage. Neuropsychological testing showed severe impairment of attention, verbal and visual memory, visuospatial function, and frontal/executive function. Language and language-related functions were normal except naming. 相似文献
895.
This article proposes 2 new approaches to test a nonzero population correlation (rho): the hypothesis-imposed univariate sampling bootstrap (HI) and the observed-imposed univariate sampling bootstrap (OI). The authors simulated correlated populations with various combinations of normal and skewed variates. With alpha set=.05, N> or =10, and rho< or =0.4, empirical Type I error rates of the parametric r and the conventional bivariate sampling bootstrap reached .168 and .081, respectively, whereas the largest error rates of the HI and the OI were .079 and .062. On the basis of these results, the authors suggest that the OI is preferable in alpha control to parametric approaches if the researcher believes the population is nonnormal and wishes to test for nonzero rhos of moderate size. 相似文献
896.
Moon-Soo Lee Young-Hoon Ko Hyoung-Seok Song Ku-Hyung Kwon Hyeon-Soo Lee Min Nam In-Kwa Jung 《Cyberpsychology & behavior》2007,10(2):278-285
As the number of internet users increases, a new game genre using the internet as a networking tool is emerging. Some game genres are regarded as having greater addiction potentials than others. Games and the internet are closely related. We investigated games frequently used by adolescents and classified each of them with the help of game professionals. We also examined internet use patterns to identify relationships between game genre and internet use patterns. 627 middle school and high school students (male 488, female 139) completed questionnaires concerning computer and game use patterns and Korean internet addiction scales. Game genres were divided into eight criteria (simulation, role playing game, web board, community, action, adventure, shooting, and sports). Using Korean internet addiction scales, 627 participants were divided into a normal group (474), a potential risk group (128), and a high-risk group (25). Each group showed significant differences in total internet addiction scores. We classified players into specific game users based upon the game types they most prefer. Role playing game users showed significantly higher internet addiction scores than web board and sports game users. Game and internet addictions are also connected with interpersonal relationship patterns. We suggest that users of some game genre have unique psychological addiction potentials that are different from others and that this influences both game selection and internet use. 相似文献
897.
With the advent of the Internet era and the maturation of electronic commerce, strategic avatar design has become an important way of keeping up with market changes and customer tastes. In this study, we propose a new approach to an adaptive avatar design that uses cognitive map (CM) as a what-if simulation vehicle. The main virtue of the new design is its ability to change specific avatar design features with objective consideration of the subsequent effects upon other design features, thereby enhancing user satisfaction. Statistical analyses of focus group interview results with a group of experts majoring in avatars and CM showed that our proposed approach could be used to effectively analyze avatar design in an adaptive and practical manner when the market situation is changing. 相似文献
898.
This study deals with the impact of virtual reality (VR) features that are embedded in a hotel website on travelers' anxiety. Having more information is thought to be a factor in relieving anxiety in travel. A hotel website can be a good place for gathering information about the accommodation. In this study, we posit that a hotel website with VR functions should lead to a reduction in travelers' anxiety about travel. We built a website of a hotel and used VR functions to show the exterior, the lobby, a guest room, and a restaurant through an interactive and spatial shot of the hotel images. The experiment was conducted with a premise that the subjects were about to embark on a journey to an unknown place and to stay at an unknown hotel whose website contained VR functions. The subjects were asked to play with VR functions of the hotel website and then to complete a survey with questions regarding the degree of anxiety on the travel and psychological relief that might have been perceived by the subjects. The result confirms our hypothesis that there is a statistically significant relationship between the degree of travel anxiety and psychological relief caused by the use of VR functions of a hotel website. 相似文献
899.
This article describes and accounts for variable interests in engineering ethics in France, Germany, and Japan by locating recent initiatives in relation to the evolving identities of engineers. A key issue in ethics education for engineers concerns the relationship between the identity of the engineer and the responsibilities of engineering work. This relationship has varied significantly over time and from place to place around the world. One methodological strategy for sorting out similarities and differences in engineers’ identities is to ask the “who” question. Who is an engineer? Or, what makes one an engineer? While engineering ethics has attracted little interest in France and formal education in the subject might be seen as redundant, German engineering societies have, since the conclusion of World War II, demanded from engineers a strong commitment to social responsibility through technology evaluation and assessment. In Japan, a recent flourishing of interest in engineering ethics appears to be linked to concerns that corporations no longer function properly as Japanese “households.” In each case, deliberations over engineering ethics emerge as part of the process through which engineers work to keep their fields in alignment with changing images of advancement in society. 相似文献
900.
Helen Lee 《Journal of Contemporary Religion》2007,22(1):91-104
This article provides a critical qualitative analysis of popular mind-body-spirit books. Typically, these books present a hybrid combining spirituality with self-help and popular psychology. They promise to soothe, heal, and liberate the reader from what is construed as a mundane, desolate life and an environmental and social context of despair. Constructions of transformation and liberation are pervasive in these books. The analysis attends to meaning and rhetoric. Three discourses are delineated, each of which constructs transformation and liberation. In addition, while it is assumed that the authors produce a particular version of spirituality in these books rather than present the truth in a value-neutral way, this analysis attends to the rhetorical strategies that can work to make the authors’ message appear as literal and factual to the reader. 相似文献