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排序方式: 共有1010条查询结果,搜索用时 15 毫秒
881.
Van Steendam G Dinnyés A Mallet J Meloni R Casabona CR González JG Kure J Szathmáry E Vorstenbosch J Molnár P Edbrooke D Sándor J Oberfrank F Cole-Turner R Hargittai I Littig B Ladikas M Mordini E Roosendaal HE Salvi M Gulyás B Malpede D 《Science and engineering ethics》2006,12(4):731-793
This paper reports on the meeting of the Sounding Board of the EU Reprogenetics Project that was held in Budapest, Hungary, 6-9 November 2005. The Reprogenetics Project runs from 2004 until 2007 and has a brief to study the ethical aspects of human reproductive cloning and germline gene therapy. Discussions during The Budapest Meeting are reported in depth in this paper as well as the initiatives to involve the participating groups and others in ongoing collaborations with the goal of forming an integrated network of European resources in the fields of ethics of science. 相似文献
882.
883.
Health-compromising lifestyles involve stable patterns of behavior and are associated with high-risk social environments and accelerated developmental trajectories. Developmentally, antisocial behavior is associated with such lifestyles. Mediational models predicting a measure of lifetime average sexual risk behavior assessed over a 10-year period (from ages 13-14 to 22-23 years) were examined for a sample of at-risk young men. The measure included years of abstinence from intercourse as well as levels of 3 key heterosexual indicators of risk: frequency of intercourse, number of intercourse partners, and condom use. Predictors included lifetime average measures of contextual, family, and peer process variables and individual behaviors. In addition, similar models for prediction of STD contraction were assessed. A younger age of onset of intercourse was associated with higher numbers of intercourse partners after onset. As hypothesized, findings indicated mediational associations of socioeconomic status, parental monitoring, deviant-peer association, antisocial behavior, and substance use in the prediction of sexual risk behavior. Lower condom use also predicted STD contraction. 相似文献
884.
Given evidence demonstrating that infants 3 months of age and younger can utilize the Gestalt principle of lightness similarity to group visually presented elements into organized percepts, four experiments using the familiarization/novelty-preference procedure were conducted to determine whether infants can also organize visual pattern information in accord with the Gestalt principle of form similarity. In Experiments 1 and 2, 6- to 7-month-olds, but not 3- to 4-month-olds, presented with generalization and discrimination tasks involving arrays of X and O elements responded as if they organized the elements into columns or rows based on form similarity. Experiments 3 and 4 demonstrated that the failure of the young infants to use form similarity was not due to insufficient processing time or the inability to discriminate between the individual X and O elements. The results suggest that different Gestalt principles may become functional over different time courses of development, and that not all principles are automatically deployed in the manner originally proposed by Gestalt theorists. 相似文献
885.
We evaluated the impact of three factors that have been suggested to be important determinants of the diagnostic process pertaining to personality disorders: (a) the number of features representative of a personality disorder category; (b) the extent to which those features are typical of the category, and (c) the dominance or proportion of category features to the total number of features. Thirty-two clinical psychologists evaluated 12 profiles of hypothetical patients in which these factors were varied factorially. The results revealed strong effects of typicality and dominance, but no effects for number. Implications for the assessment and classification of personality disorders are discussed. 相似文献
886.
Age-related impairment in the 250-millisecond delay eyeblink classical conditioning procedure in C57BL/6 mice
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Vogel RW Ewers M Ross C Gould TJ Woodruff-Pak DS 《Learning & memory (Cold Spring Harbor, N.Y.)》2002,9(5):321-336
In this study we tested 4-, 9-, 12-, and 18-month-old C57BL/6 mice in the 250-msec delay eyeblink classical conditioning procedure to study age-related changes in a form of associative learning. The short life expectancy of mice, complete knowledge about the mouse genome, and the availability of transgenic and knock-out mouse models of age-related impairments make the mouse an excellent species for expanding knowledge on the neurobiologically and behaviorally well-characterized eyeblink classical conditioning paradigm. Based on previous research with delay eyeblink conditioning in rabbits and humans, we predicted that mice would be impaired on this cerebellar-dependent associative learning task in middle-age, at ~9 months. To fully examine age differences in behavior in mice, we used a battery of additional behavioral measures with which to compare young and older mice. These behaviors included the acoustic startle response, prepulse inhibition, rotorod, and the Morris water maze. Mice began to show impairment in cerebellar-dependent tasks such as rotorod and eyeblink conditioning at 9 to 12 months of age. Performance in hippocampally dependent tasks was not impaired in any group, including 18-month-old mice. These results in mice support results in other species, indicating that cerebellar-dependent tasks show age-related deficits earlier in adulthood than do hippocampally dependent tasks. 相似文献
887.
The effects of damage to the pulvinar nucleus of the thalamus in humans on reflexive orienting and selective attention were investigated. In a spatial orienting task three patients with unilateral pulvinar damage determined the location of a visual target that followed a cue that was not informative as to the targets location. Contralesional targets were responded to more slowly than ipsilesional targets. Also, at long cue target intervals patients responses to contralesional targets that appeared at previously cued locations were slower than to non-cued locations indicating that pulvinar damage does not affect inhibition of return. In the selective attention task two of the patients identified a target that appeared at one level of a global-local hierarchical stimulus while ignoring a distractor present at the other level. The distractor indicated either the same response as the target or a different response. Response times to targets in both visual fields were similar as were interference effects from the ignored distractors. These data indicate that engaging attention contralesionally is not impaired in discrimination tasks and that filtering of irrelevant information was not impaired contralesionally. 相似文献
888.
Deborah J. Jones Terri Lewis Alan Litrownik Richard Thompson Laura J. Proctor Patricia Isbell Howard Dubowitz Diana English Bobby Jones Daniel Nagin Desmond Runyan 《Journal of abnormal child psychology》2013,41(1):139-150
A robust literature links childhood sexual abuse (CSA) to later substance use and sexual risk behavior; yet, relatively little empirical attention has been devoted to identifying the mechanisms linking CSA to risky behavior among youth, with even less work examining such processes in boys. With the aim of addressing this gap in the literature, the current study examined the indirect effect of childhood sexual abuse (CSA; from age 2 to 12) trajectory group on risky behavior at age 14 (alcohol use & sexual intercourse) via the intervening role of caregiver-reported internalizing and externalizing problems at age 12. Analyses were conducted with a subsample of youth (n?=?657 sexual intercourse; n?=?667 alcohol use) from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN), a multisite prospective study of youth at risk for maltreatment. For boys and girls, there was an indirect effect from CSA to sexual intercourse through externalizing problems. The same pattern emerged for alcohol use, but only for girls. Findings did not support an indirect path through internalizing problems for either boys or girls for either outcome. Findings suggest more focal targets for prevention efforts aimed at maintaining the health and safety of maltreated boys and girls during the adolescent transition. 相似文献
889.
Literature in the area of rape has been dominated by the psychiatric perspective leading to the view of rape as an individualistic, ideosyncratic and psychopathological problem. This leads to a conception of the rapist as a special criminal who is somehow different from his fellow prisoners. This paper proposes to study rapists as emotionally average men who have been socialized to view aggressive sexual behavior as appropriate in various situations. A comparison of rapists’ attitudes toward women, violence and rape with that of other felons reveals that their rape relevant attitudes are more extreme. It is proposed that the prevailing rape myths that exist in the society at large serve the function of providing excuses and justifications for rapists. 相似文献
890.