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801.
Size and reversal learning in the beagle dog as a measure of executive function and inhibitory control in aging 总被引:6,自引:0,他引:6 下载免费PDF全文
Tapp PD Siwak CT Estrada J Head E Muggenburg BA Cotman CW Milgram NW 《Learning & memory (Cold Spring Harbor, N.Y.)》2003,10(1):64-73
Several studies converge on the idea that executive processes age earlier than other cognitive processes. As part of a larger effort to investigate age-related changes in executive processes in the dog, inhibitory control was measured in young, middle-aged, old, and senior dogs using size discrimination learning and reversal procedures. Compared to young and middle-aged dogs, old and senior dogs were impaired on both the initial learning of the size task and the reversal of original reward contingencies. Impaired performance in the two aged groups was characterized as a delay in learning the correct stimulus-reward contingencies and, among the senior dogs in particular, an increase in perseverative responding. These separate patterns of reversal impairments in the old and senior dogs may reflect different rates of aging in subregions of the frontal cortex. 相似文献
802.
Common cultural stereotypes promote women’s submission to men, especially within intimate heterosexual relationships. Mirroring these stereotypes, women possess nonconscious associations between sex and submission (Sanchez, Kiefer & Ybarra, 2006). Moreover, women’s sex-submission associations predict greater reports of engagement in submissive sexual behavior (Sanchez et al., 2006). In the present research, we again found that women associate sex with submission at a nonconscious level. Study 1 showed that women’s nonconscious sex-submission associations predict reduced subjective arousability. Study 2 further demonstrated that these associations predict impaired ability to reach orgasm among women. These findings suggest that sex-submission associations may adversely affect women’s sexual functioning. 相似文献
803.
We examined recollective experience in odor memory as a function of age, intention to learn, and familiarity. Young and older adults studied a set of familiar and unfamiliar odors with incidental or intentional encoding instructions. At recognition, participants indicated whether their response was based on explicit recollection (remembering), a feeling of familiarity (knowing), or guessing. The results indicated no age-related differences in the distribution of experiential responses for unfamiliar odors. By contrast, for familiar odors the young demonstrated more explicit recollection than the older adults, who produced more know and guess responses. Intention to learn was unrelated to recollective experience. In addition, the observed age differences in remember responses for familiar odors were eliminated when odor naming was statistically controlled. This suggests that age-related deficits in activating specific odor knowledge (i.e., odor names) play an important role for age differences in recollective experience of olfactory information. 相似文献
804.
Gillis CM 《The Journal of medical humanities》2006,27(2):105-115
This essay explores how strategies integral to inquiry in the humanities provide insights into developing an interdisciplinary approach to studies of death and dying that will be relevant to medical practice as well as to humanistic study. The author asks how we can produce new modes of knowledge in an area where "knowing" is highly problematized and argues that while a putative field of death and dying studies must include a range of disciplinary approaches it must also account for lived, subjective experience and the ways that we, as individuals and as a culture, create meaning. 相似文献
805.
Women who become mothers at an early age are characterised by socio-economic disadvantage and unhealthy lifestyles; however, some cope extremely well. This paper describes Australian women who become mothers at an early age, in order to identify factors that predict coping. The younger cohort of the Australian Longitudinal Study of Women's Health was used to identify 1064 young women who became mothers between Survey 1 and Survey 2. These women were categorised on the basis of the Mental Health Index of the SF-36 as having High, Normal or Low mental health. Survey 1 data were used to examine predictors, and Survey 2 data to examine correlates, of mental health. Surprisingly, few socio-demographic or health-related variables predict level of coping with early motherhood. Women who would have High mental health as mothers were likely to be in paid work, had few symptoms, and had low levels of stress. They were least likely to have a history of miscarriage and most likely to use contraception. There were no significant effects for other socio-demographic factors, or health-related behaviours. In the longer term, however, all young mothers may suffer an increasing level of disadvantage and distress relative to their peers. 相似文献
806.
Many languages without separate terms for green and blue are or were spoken in locations receiving above-average exposure to ultraviolet-B (UV-B) radiation. It has been proposed that this correlation is caused by premature lens aging. This conclusion was supported by an experiment in which younger observers used the term "blue" less often when they described simulated paint chips filtered through the equivalent of an older observer's lens-removing much short-wavelength light-than when they described the unfiltered versions of the same paint chips. Some stimuli that were called "blue" without simulated aging were called "green" when filtered. However, in the experiment reported here, we found that the proportion of "blue" color-name responses did not differ between younger subjects and older observers with known ocular media optical densities. Color naming for stimuli that were nominally green, blue-green, or blue was virtually identical for older and younger observers who viewed the same (unfiltered) stimuli. Our results are inconsistent with the lens-brunescence hypothesis. 相似文献
807.
The purpose of this study was to determine the level of β-thalassemia awareness among Italians living on the eastern side
of Sicily (Bronte, Catania, and Tortorici, Messina), Italian-Americans, and Americans of other ethnic backgrounds (Other-Americans).
A questionnaire was developed which asked respondents knowledge questions about both β-thalassemia and Down Syndrome. Five
hundred questionnaires were distributed, and 456 were ultimately returned and analyzed (150 Italians, 156 Italian-Americans,
150 Other-Americans). Italians answered an average of 55% of the β-thalassemia correctly compared to scores of 17 and 24%
for the Italian-Americans and Other-Americans, respectively. The groups did not differ in their knowledge of Down Syndrome
(all answered between 58 and 60% of the questions correctly on average). Over 80% of the Italian respondents had heard of
β-thalassemia compared to only 19% of the Italian-Americans. β-Thalassemia education programs in Italy appear to have dramatically
increased awareness of the disorder. Similar programs need to be developed for at-risk populations in the United States. 相似文献
808.
809.
Three studies investigated how experiencing nearby locations together in time influences memory for location. Seven-, 9-, and 11-year-old children and adults learned 20 object locations in a small-scale space. The space was divided into regions by lines or walls. In Study 1, participants learned the locations either region by region or in a random order. Following learning, participants replaced the objects without the aid of the dots marking the locations and the boundaries subdividing the space. They replaced the objects in any order they chose. After experiencing the locations in random orders during learning, only adults underestimated distances between locations belonging to the same group (i.e., region). Conversely, 9- and 11-year-old children and adults who had experienced the locations region by region during learning underestimated these distances. These findings suggest that experiencing nearby locations together in time increases the weight children assign to categorical information in their estimates of location. Results from Studies 2 and 3 in which participants learned the locations region by region and then replaced the objects region by region (Study 2) or in a random order (Study 3) were similar, highlighting the importance of spatiotemporal cues in memory for location. (c) 2002 Elsevier Science (USA). 相似文献
810.
One hallmark of vision in adults is the dichotomy between color and motion processing. Specifically, areas of the brain that encode an object's direction of motion are thought to receive little information about object color. We investigated the development of this dichotomy by conducting psychophysical experiments with human subjects (2-, 3-, and 4-month-olds and adults), using a novel red-green stimulus that isolates color-based input to motion processing. When performance on this red-green motion stimulus was quantified with respect to performance on a luminance (yellow-black) standard, we found stronger color-based motion processing in infants than in adults. These results suggest that color input to motion areas is greater early in life, and that motion areas then specialize to the adultlike state by reweighting or selectively pruning their inputs over the course of development. 相似文献