首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   644篇
  免费   75篇
  国内免费   45篇
  764篇
  2024年   2篇
  2023年   23篇
  2022年   19篇
  2021年   18篇
  2020年   44篇
  2019年   40篇
  2018年   40篇
  2017年   47篇
  2016年   52篇
  2015年   28篇
  2014年   36篇
  2013年   131篇
  2012年   24篇
  2011年   16篇
  2010年   14篇
  2009年   12篇
  2008年   23篇
  2007年   28篇
  2006年   25篇
  2005年   35篇
  2004年   20篇
  2003年   16篇
  2002年   12篇
  2001年   12篇
  2000年   7篇
  1999年   5篇
  1998年   6篇
  1997年   2篇
  1996年   2篇
  1995年   3篇
  1994年   1篇
  1993年   2篇
  1992年   2篇
  1990年   3篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1984年   2篇
  1981年   1篇
  1980年   1篇
  1977年   2篇
  1976年   1篇
排序方式: 共有764条查询结果,搜索用时 8 毫秒
61.
ZnSe nanowires, 5–10?nm wide and several microns long, were fabricated by Au-catalyzed molecular beam epitaxy. Specially designed silicon–silicon dioxide substrates allowed an examination of individual nanowires with a combination of phase-contrast high-resolution transmission electron microscopy, Z-contrast scanning transmission electron microscopy imaging and energy-dispersive X-ray spectroscopy using a low-current electron probe with a diameter of 0.2?nm. Experimental results demonstrate direct evidence of Au incorporation within single-crystal sphalerite ZnSe nanowires.  相似文献   
62.
In this paper, I argue that it is in the fourteenth century that the problem of the compatibility or unity of efficient and final causality emerges. William Ockham and John Buridan start to flirt with a mechanized view of nature solely explainable by efficient causality, and they hence push final causality into the human mind and use it to explain for example action, morality and the good. Their argumentation introduces the problem of how to give a unified account of the world, that is, how are nature and freedom compatible. In the paper, I set up the discussion by going through some of the problems associated with final causality in the seventeenth century and show that Ockham and Buridan's problems are similar. I then argue using a formulation from Leibniz's Monadology that the problems here traced should be seen as versions of the mind/body problem.  相似文献   
63.
Appreciating human movement can be a powerful aesthetic experience. We have used apparent biological motion to investigate the aesthetic effects of three levels of movement representation: body postures, movement transitions and choreographic structure. Symmetrical (ABCDCBA) and asymmetrical (ABCDBCA) sequences of apparent movement were created from static postures, and were presented in an artificial grammar learning paradigm. Additionally, “good” continuation of apparent movements was manipulated by changing the number of movement path reversals within a sequence. In an initial exposure phase, one group of participants saw only symmetrical sequences, while another group saw only asymmetrical sequences. In a subsequent test phase, both groups rated all sequences on an aesthetic evaluation scale. We found that posture, movement, and choreographic structure all influenced aesthetic ratings. Separate ratings for the static body postures presented individually showed that both groups preferred a posture that maximized spatial symmetry. Ratings for the experimental sequences showed that both groups gave higher ratings to symmetrical sequences with “good” continuation and lower ratings to sequences with many path reversals. Further, participants who had been initially familiarized with asymmetrical sequences showed increased liking for asymmetrical sequences, suggesting a structural mere exposure effect. Aesthetic preferences thus depend on body postures, apparent movement continuation and choreographic structure. We propose a hierarchical model of aesthetic perception of human movement with distinct processing levels for body postures, movements and choreographic structure.  相似文献   
64.
Sprague-Dawley (SD) rats were given X-irradiation (150 R) on Day 17 of gestation. After birth, all male pups were pooled once and then assigned randomly to irradiated mothers and control mothers. Offspring were administered an open-field test at about 7 weeks of age. The analysis was performed on the basis of two approaches: In the per subject approach, individual subject data (aggregation across Day 2 through Day 4) were treated as the basic unit of statistical analysis. In the per litter approach, double aggregation (aggregation across Day 2 through Day 4 for each subject and aggregation across subjects within each litter) was used. The per subject approach was slightly more sensitive as to the treatment effect, but it induced a reduction in the magnitude of eta squared. A principal component analysis was performed using eta squared together with those of several reference groups. Results were plotted on a map constructed from component scores. The characteristics of behavior in X-irradiated rats were very similar to those of the earlier stage of trials in terms of the location on the map. The postnatal maternal effect on open-field behavior was not serious and was adequately negligible in practice. A new fostering procedure was proposed and its advantages discussed.  相似文献   
65.
The authors conducted 4 experiments to test whether hemispheric lateralization occurs for the processing of geometric word–shape combinations. In 3 experiments, participants responded to geometric shapes combined with geometric words (square, circle, triangle). In the 4th experiment, stimuli were combinations of geometric shapes and nongeometric words. The authors predicted that it would take longer to respond in incongruent conditions (e.g., the word “square” combined with the shape of a circle) than in congruent conditions. The authors found the strongest incongruency effects for the dominant hemisphere—that is, the left hemisphere for responding to words and the right hemisphere for responding to shapes. A Shape Interfering Properties hypothesis (SIP) is a possible explanation for these results.  相似文献   
66.
ABSTRACT. The shape bias is an attentional preference children show for the shape of an object over other aspects of the object in a word-learning context. This bias, which aids in establishing a word-object pairing, was investigated in 12-, 18-, and 24-month-old children (n = 90) across noun, adjective, and no-label conditions. The present research presents evidence of development across this time span; there was a transition from a label reducing the chance of shape extensions to indiscriminate shape extensions to a label increasing the chance of shape extensions. This research supports the notion that children are focusing their extensions more toward shape during the course of development thereby developing a more mature and more specialized shape bias.  相似文献   
67.
By using inverse dynamics and forceplate recordings, this study established the principle of oscillating systems and the influence of gravity and body parameters on the programming of the gait parameters, step frequency and length. Calculation of the ratio of the amplitude of the center of mass (CM) and the center of foot pressure (CP) oscillations yielded an equation and established a biomechanical constant, the natural body frequency (NBF). NBF appears to be an absolute invariant parameter, specific to human standing posture and gait in terrestrial gravity, which influences the relative positions of CM and CP and whose value separates the frequency bands of standing posture from those for gait. This equation was tested by using the experimental paradigm of stepping in place and then used in calculating the magnitude of CM oscillations during gait. The biomechanical analysis of the experimental observations allows one to establish the relationships between body parameters and gravity and the central programming of locomotor parameters.  相似文献   
68.
Testosterone has been linked to a sexual preference for bodies rather than faces. Low digit ratio (2D:4D) and high facial width-to-height ratio (WHR) are associated with high prenatal testosterone. We tested whether low 2D:4D and high facial WHR were correlated with a preference for bodies over faces. Our sample consisted of 109 college students (64 males). A two-way analysis of variance demonstrated a significant main effect of digit ratio on the priority placed on paying attention to faces or bodies such that low 2D:4D was linked to a preference for bodies, but the effect of sex was not significant. There were no significant interaction effects. Another two-way analysis of variance revealed no significant effects for facial WHR and attentional priority but significant associations between sex and attentional priority. There were no significant interaction effects. Our findings indicate that individuals with low digit ratios tended to pay more attention to bodies than to faces compared with individuals with higher digit ratios, independently of sex. We also found that males tended to pay more attention to bodies than to faces compared with females, independently of facial WHR.  相似文献   
69.
In this paper we describe psychotherapeutic work carried out in a paediatric hospital to illustrate the important contribution of a psychoanalytically-oriented approach in a hospital context. The work concerns an adolescent boy who had undergone several surgical operations with the result that some of his natural orifices were obstructed and artificial ones had to be created. He was referred to us because he refused pharmacological and rehabilitative treatment necessary prior to further surgery and his eventual recovery. The boy's experience of loss of control of his life and the more primitive anxieties of not feeling safely contained in his physical and psychic skin emerged and were worked through in the psychotherapeutic relationship. The parallel work with medical staff reduced the risk of splitting and acting out by the patient and professionals. The approach adopted enabled this boy to resume his medical treatment and his developmental process.  相似文献   
70.
We tested the possibility that the five‐factor model of personality is associated with three measures of body weight and with changes in their levels over time and that these associations are gender specific. The study was conducted at two points of time, Time 1 (2664 participants) and Time 2 (1492 participants), over approximately 4 years, controlling for gender, age, education, and having a chronic disease. Body weight was assessed by body mass index, waist circumference, waist‐to‐hip ratio, and the five‐factor model by Saucier's Mini‐Markers. Cross‐sectional regression results indicated that conscientiousness was negatively associated with the three body weight measures, whereas neuroticism and extraversion were positively associated with the three body weight measures. The longitudinal regression results indicate that extraversion was associated with an increase in two of the body weight measures. Neuroticism was associated with increase in all three body weight measures and more strongly for women than for men. Openness was associated with a decrease in all three body weight measures for women, but this association was not significant for men. These findings help identify personality traits that lead to risk of weight gain and point to the modifying role of gender. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号