全文获取类型
收费全文 | 4613篇 |
免费 | 94篇 |
国内免费 | 37篇 |
专业分类
4744篇 |
出版年
2023年 | 10篇 |
2022年 | 9篇 |
2020年 | 14篇 |
2019年 | 8篇 |
2018年 | 16篇 |
2015年 | 7篇 |
2014年 | 15篇 |
2013年 | 12篇 |
2012年 | 470篇 |
2011年 | 496篇 |
2010年 | 108篇 |
2009年 | 67篇 |
2008年 | 411篇 |
2007年 | 438篇 |
2006年 | 404篇 |
2005年 | 321篇 |
2004年 | 280篇 |
2003年 | 304篇 |
2002年 | 223篇 |
2001年 | 152篇 |
2000年 | 197篇 |
1999年 | 95篇 |
1998年 | 22篇 |
1997年 | 16篇 |
1996年 | 15篇 |
1995年 | 18篇 |
1994年 | 25篇 |
1993年 | 16篇 |
1992年 | 22篇 |
1991年 | 33篇 |
1990年 | 29篇 |
1989年 | 40篇 |
1988年 | 42篇 |
1987年 | 32篇 |
1986年 | 35篇 |
1985年 | 32篇 |
1984年 | 14篇 |
1983年 | 24篇 |
1982年 | 13篇 |
1981年 | 24篇 |
1980年 | 10篇 |
1978年 | 22篇 |
1965年 | 18篇 |
1964年 | 8篇 |
1963年 | 16篇 |
1959年 | 8篇 |
1958年 | 30篇 |
1957年 | 22篇 |
1956年 | 13篇 |
1955年 | 7篇 |
排序方式: 共有4744条查询结果,搜索用时 8 毫秒
891.
892.
Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity, and measurements are highly reliable. As the method is theoretically founded, it also has high validity. TVA-based assessment has recently been used to investigate a broad range of neuropsychological and neurological conditions. We present the method, including the experimental paradigm and practical guidelines to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical networks that include several regions outside the visual system. The two visual capacity parameters are functionally separable, but seem to rely on largely overlapping brain areas. 相似文献
893.
Although it is frequently argued that empathy is increased by similar experiences, this idea has rarely been tested. This study investigated the relationship between empathy and prior similar experience. Participants read four different stories and rated the degree of empathy they felt. They also reported the extent to which they had prior similar experience of the events in the stories. We found that these self-reports of prior similar experience increased empathy for the persons in the stories. Similar experience may be an important situational antecedent for feeling empathy for another person. Pointing out similarities among experiences may be a fruitful means of training empathy. 相似文献
894.
Using a name-based categorization task, Nazzi found in 2005 that French-learning 20-month-olds can make use of one-feature consonantal contrasts between new labels but fail to do so with one-feature vocalic contrasts. This asymmetry was interpreted as developmental evidence for the proposal that consonants play a more important role than vowels at the lexical level. In the current study using the same task, we first show that by 30 months French-learning infants can make use of one-feature vocalic contrasts (e.g., /pize/–/pyze/). Second, we show that in a situation where infants must neglect either a consonantal one-feature change or a vocalic one-feature change (e.g., match a /pide/ with either a /tide/ or a /pyde/), both French- and English-learning 30-month-olds choose to neglect the vocalic change rather than the consonantal change. We argue that these results suggest that by 30 months of age, infants still give less weight to vocalic information than to consonantal information in a lexically related task even though they are able to process fine vocalic information. 相似文献
895.
Research on emotion processing in the visual modality suggests a processing advantage for emotionally salient stimuli, even at early sensory stages; however, results concerning the auditory correlates are inconsistent. We present two experiments that employed a gating paradigm to investigate emotional prosody. In Experiment 1, participants heard successively building segments of Jabberwocky "sentences" spoken with happy, angry, or neutral intonation. After each segment, participants indicated the emotion conveyed and rated their confidence in their decision. Participants in Experiment 2 also heard Jabberwocky "sentences" in successive increments, with half discriminating happy from neutral prosody, and half discriminating angry from neutral prosody. Participants in both experiments identified neutral prosody more rapidly and accurately than happy or angry prosody. Confidence ratings were greater for neutral sentences, and error patterns also indicated a bias for recognising neutral prosody. Taken together, results suggest that enhanced processing of emotional content may be constrained by stimulus modality. 相似文献
896.
Geschwind and Behan (1982) and Geschwind and Galaburda (1985a, 1985b, 1985c) suggested a correlation between brain laterality and immune disorders. To test whether this hypothesis holds true not only for the frequency of immune diseases and circulating autoantibodies, but extends also to cellular immunity, we examined the association between handedness and markers of cellular immunity. Twenty-seven left-handed and 37 right-handed subjects were serologically screened for cellular parameters and 22 left-handed subjects were typed for human leukocyte antigen (HLA). When compared to the right-handers, the left-handed group showed a significant decrease in the inflammatory cell types CD3(+) T cells (total T cells), CD4(+) T cells (T-helper cells), and HLA-Dr (MHC-II, antigen-presenting cells) as well as in the CD19(+) cells (B cells) and CD16/CD57(+) cells (natural killer cells). We assume a relationship exists between cerebral hemispheric specialisation and the immune system not only for humoral but also for cellular immunity, and we discuss the role of the major histocompatibility complex in neurological and immunological development. 相似文献
897.
Epidemiological studies have shown that chronic work stress or unfavourable psychosocial work conditions are prospectively associated with different adverse health outcomes. The aim of the present cross-sectional study was to investigate the relationship between work-related chronic stress as well as exhaustion and a cumulative measure of physiological wear-and-tear called allostastic load (AL). AL could be a possible biological pathway for how chronic work stress and exhaustion lead to health impairments in the long run. As the teaching profession has been proposed to be a potentially high stressful occupation, chronic work stress (effort-reward-imbalance) and exhaustion were assessed in 104 female school teachers. AL was first analyzed according to McEwen's classical model comprised of ten parameters including cortisol, epinephrine and norepinephrine, dehydroepiandrosterone-sulphate (DHEA-S), waist/hip-ratio (WHR), glycosylated haemoglobin (HbA1c), high-density lipoprotein (HDL), total cholesterol/HDL-ratio, and systolic and diastolic blood pressure. Additionally it was extended to include tumor-necrosis-factor-alpha (TNF-alpha), C-reactive protein (CRP), fibrinogen, D-dimer, percent-body-fat, triglycerides, and glucose levels. A substantial proportion of our sample was highly exhausted whereas relatively few teachers showed high effort-reward-imbalance. AL scores were significantly higher in women high on effort-reward-imbalance or suffering from exhaustion. Although all teachers had been in a good health status, chronic work stress as well as exhaustion appears to be associated with changes in a multi-system summary indicator of physiological risk. 相似文献
898.
Chumaeva N Hintsanen M Ravaja N Puttonen S Heponiemi T Pulkki-Råback L Juonala M Raitakari OT Viikari JS Keltikangas-Järvinen L 《Stress (Amsterdam, Netherlands)》2009,12(4):283-293
The present study examined the interaction between vital exhaustion and cardiac reactivity and recovery on preclinical atherosclerosis assessed by carotid intima-media thickness (IMT) in young men and women. We measured heart rate (HR), respiratory sinus arrhythmia (RSA), and pre-ejection period (PEP) in response to mental arithmetic and speech tasks. Vital exhaustion and carotid IMT were also measured. Significant associations were observed for men aged 28-37 years, but not for men aged 22-25 years, nor for women in these age groups. It was shown that, among highly exhausted men in the older age group, lower HR reactivity was related to greater IMT. Our results also imply that, among non-exhausted men in this age group, slow HR and RSA recovery after acute stress predicted higher IMT. These results suggest that long-term stress as assessed by vital exhaustion is a risk only if it has resulted in ineffective cardiac stress reactivity. Autonomic imbalance resulting from chronic stress may be the common mechanism linking vital exhaustion and cardiac responsiveness to an increased risk of atherosclerosis. 相似文献
899.
900.
In this study adults performed numerical and physical size judgments on a symbolic (Arabic numerals) and non-symbolic (groups
of dots) size congruity task. The outcomes would reveal whether a size congruity effect (SCE) can be obtained irrespective
of notation. Subsequently, 5-year-old children performed a physical size judgment on both tasks. The outcomes will give a
better insight in the ability of 5-year-olds to automatically process symbolic and non-symbolic numerosities. Adult performance
on the symbolic and non-symbolic size congruity tasks revealed a SCE for numerical and physical size judgments, indicating
that the non-symbolic size congruity task is a valid indicator for automatic processing of non-symbolic numerosities. Physical
size judgments on both tasks by children revealed a SCE only for non-symbolic notation, indicating that the lack of a symbolic
SCE is not related to the mathematical or cognitive abilities required for the task but instead to an immature association
between the number symbol and its meaning. 相似文献