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991.
It has been shown previously that the immediate-early genes, c-fos and c-jun mRNA are induced in the 1-day-old chick forebrain after one-trial passive avoidance training in which chicks learn to avoid pecking at a bitter-tasting bead. Here, we have studied the expression of their proteins using antibodies to Fos and Jun. Western blotting disclosed two immunoreactive bands for the anti-Fos antibody (47 and 54 kD) and two immunoreactive bands for the anti-Jun antibody (39 and 54 kD). Two hours post-training there was an increase in the number of Fos-positive stained nuclei in right intermediate medial hyperstriatum ventrale (IMHV) (P<0.01), left IMHV (P<0.05), right lobus parolfactorius (LPO) (P<0.025) and left LPO (P<0.05) of birds trained on the bitter bead compared with controls that had pecked a water-coated bead. Staining for Jun protein was significantly greater in the right LPO of trained chicks (P<0.01). Other forebrain regions showed no increase over quiet control levels. The findings are discussed in the context of the cascade of events involved in passive avoidance memory consolidation in the day-old chick.  相似文献   
992.
Survivors of child sexual abuse suffer serious short- and long-term psychological consequences. Sexual revictimization as an adult is one of the consequences that has been reported. At present, there is no theoretical model identifying the risk factors that result in child sexual abuse survivors being at greater risk of experiencing an adult sexual assault. The proposed model is designed to integrate existing research, stimulate further empirical work, and eventually aid in the development of a program to prevent revictimization. The variables hypothesized to play a mediating role in the pathway to revictimization include: severe psychological symptoms as a consequence of the child sexual abuse, poor coping styles, an insecure attachment style, hyperfemininity, delinquent behavior, drug use, and high risk sexual behavior.  相似文献   
993.
Children showing a comorbid behavior pattern of hyperactivity-impulsivity-inattention and conduct problems (HIA + CP) were contrasted to children having only an internalizing and externalizing behavior pattern (I + E) and matched controls. Children displaying the HIA + CP behavior pattern were at greater risk on a number of outcome measures in social and academic domains beginning in Grade 3 and continuing into Grade 4. The most marked differences among the three groups were found on peer measures of rejection and friendship and teacher ratings of social skills. On average, almost two-thirds of the HIA + CP group were rejected by their peers compared to one-third of the I + E group and only 12.5% controls. Over 70% of the HIA + CP group had no reciprocated friendships from Grade 3 to Grade 4 compared to less than half of the I + E group and approximately one-fourth of controls. Contrary to much theorizing in the literature, the HIA + CP and I + E groups showed average levels of academic self-concept and did not differ from controls in on measures of social self-concept and academic self-concept and general self-esteem. These findings were interpreted in light of positive illusory biases and the established link between aggressive behavior and egotism. The current article offers partial support for Lynam's (1996) notion of the fledgling psychopath.  相似文献   
994.
One central but unrecognized strand of the complex debate between W. V. Quine and Donald Davidson over the status of psychology as a science turns on their disagreement concerning the compatibility of strict psychophysical, semantic-determining laws with the possibility of error. That disagreement in turn underlies their opposing views on the location of semantic determinants: proximal (on bodily surfaces) or distal (in the external world). This paper articulates these two disputes, their wider context, and argues that both are fundamentally misconceived. There is no special tension between error and strict semantic-determining laws; moreover, the purported bearing of that issue on the dispute over the location of semantic determinants depends upon a mistaken conception of the relation between the nomic status of generalizations and degree of distance between explanans and it explananda. Finally, the wider significance of these conclusions for related contemporary debates is noted. And independent considerations about the possibility of communication, also present in Quine's and Davidson's thinking, are brought to bear on the question of the location of semantic determinants. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
995.
Stack  Steven 《Sex roles》1998,38(7-8):501-520
The previous work on suicide acceptability hasneglected gender specific analysis of the marriagesuicide acceptability linkage as well as cross-nationalanalysis. The present study fills these gaps in the literature through an analysis of 15nations. Controlling for alternative predictors ofsuicide acceptability, marriage lowers suicideacceptability for both males and females. Further,marriage lowers suicide acceptability more for men than forwomen. This gendered relationship has the same strengthin nations both high and low in economic genderequality. The results provide the first comparativeevidence on the subject. The findings support the notionthat men derive relatively more benefits from marriagethan women. However, the strongest correlates of suicideacceptability (e.g., religiosity, liberalism, French residence) affect men and womenequally.  相似文献   
996.
Posavac  Heidi D.  Posavac  Steven S.  Posavac  Emil J. 《Sex roles》1998,38(3-4):187-201
Despite the popular belief that the thinstandard of female attractiveness currently presented inthe media is a primary contributor to the high level ofconcern with body weight among women, experimental studies have not shown that exposure to mediaimages increases women's weight concern. Threeexperiments are reported demonstrating that exposure tomedia images does often result in increased weightconcern among women, but that body dissatisfaction, astable personality characteristic, is a moderator ofvulnerability to this effect. Although most womenreported higher weight concern when exposed to media vs. neutral images, women with low initial bodydissatisfaction did not. In addition, this researchsuggests that negative effects on weight concern mayresult from even passive exposure to media images, but that exposure to realistic attractivenessis less likely to cause increased weight concern. Theethnicity of the participants in these studies reflectedthat of the local population, with over 90% white. The nonwhite participants primarily belonged toone of the following groups; Asian, Pacific Islander,Latino.  相似文献   
997.
Sources of Dual-Task Interference: Evidence From Human Electrophysiology   总被引:6,自引:0,他引:6  
When an individual attempts to perform two tasks at the same time, the tasks often interfere with each other. This interference has been studied for several decades with the psychological refractory period paradigm, in which two targets that require independent responses are presented on each trial, separated by a variable delay period; interference typically takes the form of increased response times for the second target at short interstimulus delays. The present study used electrophysiological recordings to determine whether a specific index of perception and categorization (the P3 wave) is delayed in the same manner as response times. Although response times for the second target were found to be greatly delayed at short interstimulus intervals, the P3 wave was not substantially delayed. This finding indicates that there was minimal interference during target identification and categorization and that the prolongation of response times in this paradigm primarily reflects a delay in a relatively late process, such as response selection.  相似文献   
998.
In a longitudinal study, we examined the relationship between exposure to community violence and anxiety, and the extent to which family social support moderated this relationship within a predominantly African American sample of 385 children in an urban public school system. Children reported notably lower anxiety levels compared to normative data for African American children. A high percentage reported witnessing a variety of violent acts. Cross-sectional results indicated that among girls exposure to violence was significantly correlated with total, physiological, and concentration anxiety. Among boys violence exposure was not associated with anxiety. Hierarchical regression analyses indicated that after controlling for gender, exposure to violence at Time 1 did not significantly predict changes in anxiety. A significant interaction was found for gender and exposure to violence on concentration anxiety; girls who reported higher initial violence exposure reported greater increases in subsequent concentration anxiety than boys. Whereas findings from our study did not support a moderating relationship of family social support on children's exposure to violence and anxiety, a strong negative relationship was found between anxiety and family support. Among children with initially low worry anxiety, those with low family social support showed greater increases in subsequent worry anxiety.  相似文献   
999.
Invited media scholars and journalists examine the general issue of nuclear waste, risk and the sicentific promises that were made, but not kept, about safe disposal. The mass media uncovered and reported on nuclear waste problems at Rocky Flats in Colorado and Hanford in Washington. Two environmental journalists review efforts to expose problems at these sites, how secrecy hampered reporting, and the effects of media coverage on nearby residents. An environmental communications scholar evaluates media coverage, the role of the U.S. Department of Energy, and the impact of secrecy on public risk perceptions and attitudes toward government nuclear waste policies.  相似文献   
1000.
Genetic discrimination is becoming an increasingly important problem in the United States. Information acquired from genetic tests has been used by insurance companies to reject applications for insurance policies and to refuse payment for the treatment of illnesses. Numerous states and the United States Congress have passed or are considering passage of laws that would forbid such use of genetic information by health insurance companies. Here we argue that much of this legislation is severely flawed because of the difficulty in distinguishing genetic from nongenetic tests. In addition, barring the use by insurance companies of a genetic test but not a nongenetic test (conceivably for the same multifactorial disease) raises issues of fairness in health insurance. These arguments suggest that ultimately the problems arising from genetic discrimination cannot be solved by narrowly focused legislation but only by a modification of the entire health care system.  相似文献   
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