全文获取类型
收费全文 | 22961篇 |
免费 | 164篇 |
出版年
2023年 | 36篇 |
2022年 | 57篇 |
2021年 | 78篇 |
2020年 | 110篇 |
2019年 | 90篇 |
2018年 | 3588篇 |
2017年 | 2934篇 |
2016年 | 2346篇 |
2015年 | 266篇 |
2014年 | 171篇 |
2013年 | 439篇 |
2012年 | 768篇 |
2011年 | 2564篇 |
2010年 | 2621篇 |
2009年 | 1521篇 |
2008年 | 1863篇 |
2007年 | 2285篇 |
2006年 | 145篇 |
2005年 | 271篇 |
2004年 | 219篇 |
2003年 | 176篇 |
2002年 | 102篇 |
2001年 | 56篇 |
2000年 | 86篇 |
1999年 | 34篇 |
1998年 | 36篇 |
1997年 | 31篇 |
1996年 | 14篇 |
1995年 | 8篇 |
1994年 | 9篇 |
1993年 | 11篇 |
1992年 | 9篇 |
1991年 | 17篇 |
1990年 | 16篇 |
1989年 | 10篇 |
1988年 | 9篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 13篇 |
1983年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1972年 | 6篇 |
1971年 | 6篇 |
1968年 | 9篇 |
1966年 | 7篇 |
1965年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 515 毫秒
261.
Pratt, Adam, and Fischer (2007) investigated the effect of surrounding targets on the time it took to move to an individual target and found that the movement
time to a central target was above the Fitts’s law line related to the first and last targets. They explained their results
in terms of a “visuomotor hypothesis.” Here, an alternative explanation is given in terms of a previously validated model
of the “available target width” that is determined by the size of the target and the width of the finger pad that is being
used to hit the target. 相似文献
262.
Ecological valence theory (EVT; Palmer & Schloss, Proceedings of the National Academy of Sciences 107:8877–8882, 2010) proposes that color preferences are due to affective responses to color-associated objects: That is, people generally like
colors to the degree that they like the objects associated with those colors. Palmer and Schloss found that the average valence
of objects associated with a color, when weighted by how well the objects matched the color (weighted affective valence estimates:
WAVE) explained 80% of the variation in preference across colors. Here, we replicated and extended Palmer and Schloss’s investigation
to establish whether color–object associations can account for sex differences in color preference and whether the relationship
between associated objects and color preference is equally strong for males and females. We found some degree of sex specificity
to the WAVEs, but the relationship between WAVE and color preference was significantly stronger for males than for females
(74% shared variance for males, 45% for females). Furthermore, analyses identified a significant inverse relationship between
the number of objects associated with a color and preference for the color. Participants generally liked colors associated
with few objects and disliked colors associated with many objects. For the sample overall and for females alone, this association
was not significantly weaker than the association of the WAVE and preference. The success of the WAVE at capturing color preference
was partly due to the relationship between the number of associated objects and color preference. The findings identify constraints
of EVT in its current form, but they also provide general support for the link between color preference and color–object associations. 相似文献
263.
Adolescence is characterized by major developmental changes that may render the individual vulnerable to stress and the development of psychopathologies in a sex-specific manner. Earlier we reported lower anxiety-like behavior and higher risk-taking and novelty seeking in rats previously exposed to peri-pubertal stress. Here we studied whether peri-pubertal stress affected the acquisition and extinction of fear memories and/or the associated functional engagement of various brain regions, as assessed with 2-deoxyglucose. We showed that while peri-pubertal stress reduced freezing during the acquisition of fear memories (training) in both sexes, it had a sex-specific effect on extinction of these memories. Moreover hippocampus, basal amygdala and cingulate and motor cortices showed higher metabolic rates during extinction in rats exposed to peri-pubertal stress. Interestingly, activation of the infralimbic cortex was negatively correlated with freezing during extinction only in control males, while only males stressed during puberty showed a significant correlation between behavior during extinction and metabolic activation of hippocampus, amygdala and paraventricular nucleus. No correlations between brain activation and behavior during extinction were observed in females (control or stress). These results indicate that exposure to peri-pubertal stress affects behavior and brain metabolism when the individual is exposed to an additional stressful challenge. Some of these effects are sex-specific. 相似文献
264.
The objective of the study is to assess views of age related changes in sexual behavior among married Thai adults age 53–57.
Results are viewed in the context of life course theory. In-depth interviews were conducted with 44 Thai adults in Bangkok
and the four regions of Thailand. Topics covered include changing sexual behavior with age, adjustment to this change, gender
differences in behavior, attitudes toward commercial sex and other non-marital sexual partners, and condom use. Most respondents
were aware of this change and saw a decrease in sexual activity and desire more often among women compared to men. At the
same time, many respondents viewed sexuality as important to a marriage. Some respondents accepted the decrease in sexual
activity and focused more on work, family and temple activities. Thai Buddhism was seen as an important resource for people
who were dealing with changes due to aging. Other persons turned to other partners including both commercial and non-commercial
partners. The influence of the HIV epidemic that began in the 1990s was seen in concerns about disease transmission with extramarital
partners and consequent attitudes toward condom use. The acceptability of extramarital partners in the family and community
ranged from acceptance to strong disapproval of extramarital relationships. 相似文献
265.
The recent trend in the feminization of the HIV epidemic poses great risk to women, especially to the wives of men who have
sex with men (MSM). The objective of the present study was to explore wives’ responses to their husbands’ sexual orientation
as well as the factors that influence their sexual health in India. For this research, 15 wives who were aware of their husbands’
sexual orientation and their husbands were interviewed separately using semi-structured in-depth interviews and focus groups.
The study explored the social and cultural structures that create gender inequality, which put women married to MSM at sexual
health risk. These factors need to be addressed carefully through existing MSM targeted interventions, without breaching the
confidentiality of either partner. 相似文献
266.
Between 1998 and 2006, twenty-seven states amended their constitutions to prohibit same sex marriage. The 2008 elections again
saw three states with ballot measures aimed at banning gay marriage. This study examines the determinants of support for those
measures in California and Florida, and includes a similar measure placed on the primary election ballot in California in
2000. Support is measured as the county-wide vote in favor of each gay marriage ban. A number of hypotheses are explored that
examine the urban/rural nature of each county, as well as the political and demographic characteristics of county residents.
It is suggested that states may be best viewed as relatively independent groupings of diverse subcultures, rather than as
homogenous populations with a single political culture. The findings reported here indicate that a host of demographic, political
and religious differences within each state influence residents’ votes on gay marriage bans. 相似文献
267.
Meilán JJ Martínez-Sánchez F Carro J Sánchez JA Pérez E 《The Spanish journal of psychology》2012,15(2):487-494
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources. 相似文献
268.
Losada A de los Angeles Villareal M Nuevo R Márquez-González M Salazar BC Romero-Moreno R Carrillo AL Fernáñdez-Fernández V 《The Spanish journal of psychology》2012,15(2):783-792
The Center for Epidemiologic Studies-Depression Scale (CES-D) is the most frequently used scale for measuring depressive symptomatology in caregiving research. The aim of this study is to test its construct structure and measurement equivalence between caregivers from two Spanish-speaking countries. Face-to-face interviews were carried out with 595 female dementia caregivers from Madrid, Spain, and from Coahuila, Mexico. The structure of the CES-D was analyzed using exploratory and confirmatory factor analysis (EFA and CFA, respectively). Measurement invariance across samples was analyzed comparing a baseline model with a more restrictive model. Significant differences between means were found for 7 items. The results of the EFA clearly supported a four-factor solution. The CFA for the whole sample with the four factors revealed high and statistically significant loading coefficients for all items (except item number 4). When equality constraints were imposed to test for the invariance between countries, the change in chi-square was significant, indicating that complete invariance could not be assumed. Significant between-countries differences were found for three of the four latent factor mean scores. Although the results provide general support for the original four-factor structure, caution should be exercised on reporting comparisons of depression scores between Spanish-speaking countries. 相似文献
269.
Polder-Verkiel SE 《Science and engineering ethics》2012,18(1):117-141
In 2008 a young man committed suicide while his webcam was running. 1,500 people apparently watched as the young man lay dying:
when people finally made an effort to call the police, it was too late. This closely resembles the case of Kitty Genovese
in 1964, where 39 neighbours supposedly watched an attacker assault and did not call until it was too late. This paper examines
the role of internet mediation in cases where people may or may not have been good Samaritans and what their responsibilities
were. The method is an intuitive one: intuitions on the various potentially morally relevant differences when it comes to
responsibility between offline and online situations are examined. The number of onlookers, their physical nearness and their
anonymity have no moral relevance when it comes to holding them responsible. Their perceived reality of the situation and
ability to act do have an effect on whether we can hold people responsible, but this doesn’t seem to be unique to internet
mediation. However the way in which those factors are intrinsically connected to internet mediation does seem to have a diminishing
effect on responsibility in online situations. 相似文献
270.