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291.
292.
Observation and analysis of large-scale human motion   总被引:2,自引:0,他引:2  
Many team sports include complex human movement, which can be observed at different levels of detail. Some aspects of the athlete's motion can be studied in detail using commercially available high-speed, high-accuracy biomechanical measurement systems. However, due to their limitations, these devices are not appropriate for studying large-scale motion during a game (for example, the motion of a player running across the entire playing field). We describe an alternative approach to studying such large-scale motion, and present a video-based, computer-aided system, developed specifically for the purpose of acquiring large-scale motion data. The baseline of our approach consists of sacrificing much of the spatial accuracy and temporal resolution of widely used biomechanical measurement systems, to obtain data on human movement that span large areas and long intervals of time. Data can be obtained for each of the observed athletes with reasonable amount of operator work. The system was developed using the recordings of a handball match. Several field tests were performed to assess measurement error, including comparison to one of the widely available biomechanical measurement systems. With the help of the system presented, we could obtain position data for all 14 handball players on a 40 x 20 m large court with RMS error better than 0.6 m, covering 1 h of action. Several results, obtained during the handball match study are presented, in order to highlight the importance of large-scale motion acquisition.  相似文献   
293.
The authorship criteria of the International Committee of Medical Journal Editors (ICMJE) are widely accepted in biomedical journals, but many studies in large and prestigious journals show that a considerable proportion of authors do not fulfill these criteria. We investigated authorship contributions in a small medical journal outside the scientific mainstream, to see if poor adherence to authorship criteria is common in biomedical journals. We analyzed statements on research contribution, as checked by the corresponding author, for individual authors of 114 research articles, representing 475 authors, submitted to the Croatian Medical Journal (CMJ) from 1999 to 2000. Only 40% of authors fulfilled the ICMJE authorship criteria. The authors listed first on the by-line were more likely to fulfill the authorship criteria than all other authors on the by-line. The percentage of authors fulfilling the ICMJE criteria of authorship decreased with the increase in the number of authors listed on the by-line. These results indicate that poor adherence to ICMJE authorship criteria is poor across biomedical journals, regardless of the size of the scientific community. Authorship and contributorship in biomedical journals, as well as editorial ethical responsibilities towards authorship criteria need critical redefinition and education of both editors and authors.  相似文献   
294.
Using M3/38 monoclonal antibody we have analyzed effects of immobilization stress on the expression of galectin-3 in liver, spleen and peritoneal macrophages from adult RFM and C3H mice, as well as from aged C3H mice (total of 22 animals). In all analyzed tissues, immobilization stress caused a significant decrease in the expression of galectin-3, ranging from 14% to 47%. The decrease of galectin-3 was observed in both strains of mice, as well as in old animals. Moreover, the same range of decrease (approximately 50%) was observed when cells grown in vitro were exposed to subculturing, or heat-shock. Although the biological significance of this effect is not known, it is very interesting that a single episode of immobilization stress was sufficient to cause a significant decrease in galectin-3, implicating that this beta-galactoside-binding lectin might be involved in the physiological response to psychological stress.  相似文献   
295.
We examined the correlations between scores on Bortner's scale and measures of aggression, distrustful, gregarious, and depression in 1,084 employees. Prospectively over 2 yr. we investigated the relationship of Type A behavior with cardiac mortality. Subjects classified as Type A had higher mean ratings on measures of aggression and distrustful than did persons classified as Type B. Mortality was lower in patients classified as reporting Type A behavior (12%) than in the patients classified as reporting Type B behavior (22%).  相似文献   
296.
Roberson and Davidoff (2000) found that color categorical perception (CP; better cross-category than within-category discrimination) was eliminated by verbal, but not by visual, interference presented during the interstimulus interval (ISI) of a discrimination task. On the basis of this finding, Roberson and Davidoff concluded that CP was mediated by verbal labels, and not by perceptual mechanisms, as is generally assumed. Experiment 1 replicated their results. However, it was found that if the interference type was uncertain on each trial (Experiment 2), CP then survived verbal interference. Moreover, it was found that the target color name could be retained across the ISI even with verbal interference (Experiment 3). We therefore conclude that color CP may indeed involve verbal labeling but that verbal interference does not necessarily prevent it.  相似文献   
297.
Pseudo MV-algebras are a non-commutative extension of MV-algebras introduced recently by Georgescu and Iorgulescu. We introduce states (finitely additive probability measures) on pseudo MV-algebras. We show that extremal states correspond to normal maximal ideals. We give an example in that, in contrast to classical MV-algebras introduced by Chang, states can fail on pseudo MV-algebras. We prove that representable and normal-valued pseudo MV-algebras admit at least one state.  相似文献   
298.
299.
Rumination was examined as a potential common mechanism linking risk factors with depression. Initially nondepressed individuals (N = 137) were assessed for presence of a ruminative response style and 4 other hypothesized risk factors for depression. They were followed for 2.5 years. Negative cognitive styles, self-criticism, dependency, neediness, and history of past depression were all significantly associated with rumination. Rumination mediated the predictive relationships of all risk factors except dependency with the number of prospective Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) major depressive episodes (MDEs; definite and subthreshold) during the follow-up period. In contrast, private self-consciousness did not mediate any relationships between risk factors and subsequent MDEs. Thus, rumination, as a special kind of self-focus, may act as a general proximal mechanism through which other vulnerability factors affect depression.  相似文献   
300.
Although previous meta-analytic evidence supports the existence of parochialism in cooperation among adults, the extent to which children and adolescents are more willing to incur a personal cost to benefit ingroups, compared to outgroups, is not yet clear. We provide the first meta-analysis on the existence and magnitude of parochialism in cooperation among pre-adults. Based on 20 experimental economics studies (k = 69, N = 5268, age = 3–19, 12 countries, published 2008–2019), a multilevel meta-analytic model revealed a small overall effect size indicating that children and adolescents were more cooperative towards ingroups (d = 0.22, 95% CI [0.07, 0.38]). A series of single-moderator analyses tested for the following conditions: participant age and sex; game type ([mini-]dictator game, prisoner's dilemma, public goods dilemma, trust game, ultimatum game); outcome interdependence; membership manipulation (between- vs. within-subjects); group type (natural vs. experimental); reward type (monetary vs. non-monetary); and country of the participant. Parochial cooperation did not vary with participants' age. Parochialism was larger in non-interdependent (dictator-type) compared to interdependent (bargaining and social dilemma) games. There were no moderating effects of group type, membership manipulation or reward type. To provide more data on how parochialism develops, primary studies should report age ranges more precisely and use more restricted age groups.  相似文献   
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