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751.
We examined actual and perceived trajectories of change in life satisfaction in a national sample of 3,793 adults, ages 24 to 74 at baseline, who provided retrospective, present, and prospective ratings on two occasions 8 to 10 years apart. There was little actual change in satisfaction ratings, but there were age differences in anticipated change, with young adults expecting things to improve and older adults expecting decline. When we compared the actual (present) ratings with corresponding past or future ratings, older adults showed more temporal realism (retrospective and anticipatory ratings matched actual levels) than did young and middle-aged adults; in other words, young and middle-aged adults showed greater illusion (retrospective and prospective ratings overestimated or underestimated actual levels). At all ages, however, temporal realism was associated with more adaptive current functioning than was illusion. We discuss these findings from a life-span developmental perspective on motivational shifts from growth to maintenance and consider the implications of accuracy in evaluating the past and future.  相似文献   
752.
Living organ donation, that is the removal and transplantation of whole organs or segments of organs that a volunteering donor can live without, has been proposed as an effective and sustainable source of transplantable organs to mitigate the deficit in supply from the traditional cadaveric donor pool. In 2006, the Irish government deemed the development of a national Living Transplant Programme a service priority. The current study aimed to investigate the efficacy of the theory of planned behaviour (TPB) in the context of living organ donation intentions in an Irish sample. One hundred and thirty five undergraduate students (75 females, 60 males; mean age 20.6 years, SD 3.76) completed a self-report questionnaire assessing TPB variables while imagining themselves in a potential living liver donation scenario. In general, attitudes towards living donation were favourable. TPB components explained 44.8% of the variance in intentions. Attitude towards living donation emerged as the strongest predictor of intention. Self-reported levels of knowledge regarding living donation were generally poor. In light of recent EU Communications proposing the expansion of the use of living donors greater understanding of the determinants, psychological implications and ethical considerations in living donation decisions is necessary.  相似文献   
753.
The aim of the current study was to determine whether age and body satisfaction predict dietary adherence in adolescents with Inflammatory Bowel Disease (IBD), and whether older females are less adherent than younger males and females. Forty-four participants aged 10–21 with IBD were recruited. Participants provided informed consent and demographics. Body satisfaction was measured by a questionnaire and a task in which participants selected their current and ideal body image out of silhouettes depicting bodies ranging from underweight to obese. Adherence was measured by marking a 100 mm visual analog scale, the 1-week completion of a dietary log, and a questionnaire evaluating coping strategies used for overcoming obstacles to dietary adherence. Age was related to dietary adherence, with younger children being more likely to adhere. Participants more satisfied with their body reported better dietary adherence. Findings remained consistent across multiple measures of body satisfaction and adherence. Healthcare providers and parents should be informed of these findings in order to improve adherence.  相似文献   
754.
Previously, we found that in the lateral amygdala (LA) of the mouse, WIN55,212-2 decreases both glutamatergic and GABAergic synaptic transmission via activation of the cannabinoid receptor type 1 (CB1), yet produces an overall reduction of neuronal excitability. This suggests that the effects on excitatory transmission override those on inhibitory transmission. Here we show that CB1 activation by WIN55,212-2 and Delta(9)-THC inhibits long-term depression (LTD) of basal synaptic transmission in the LA, induced by low-frequency stimulation (LFS; 900 pulses/1 Hz). The CB1 agonist WIN55,212-2 blocked LTD via G(i/o) proteins, activation of inwardly rectifying K+ channels (K(ir)s), inhibition of the adenylate cyclase-protein kinase A (PKA) pathway, and PKA-dependent inhibition of voltage-gated N-type Ca2+ channels (N-type VGCCs). Interestingly, WIN55,212-2 effects on LTD were abolished in CB1 knock-out mice (CB1-KO), and in conditional mutants lacking CB1 expression only in GABAergic interneurons, but were still present in mutants lacking CB1 in principal forebrain neurons. LTD induction per se was unaffected by the CB1 antagonist SR141716A and was normally expressed in CB1-KO as well as in both conditional CB1 mutants. Our data demonstrate that activation of CB1 specifically located on GABAergic interneurons inhibits LTD in the LA. These findings suggest that CB1 expressed on either glutamatergic or GABAergic neurons play a differential role in the control of synaptic transmission and plasticity.  相似文献   
755.
An automated training system was used to compare the behavior of knockout (KO) mice lacking the fragile X mental retardation protein with that of wild-type (WT) mice (C57Bl/6 strain) in the acquisition and retention of olfactory discriminations. KO and WT mice did not differ in the acquisition of a four-stage nose poke shaping procedure. In two separate experiments, mutant mice required substantially more training to acquire a series of novel olfactory discrimination problems than did control mice. The KO mice required significantly more sessions to reach criterion performance, made significantly more errors during training, and more often failed to acquire discriminations. Both KO and WT mice showed similar error patterns when learning novel discriminations and both groups showed evidence of more rapid learning of later discriminations in the problem series. Both groups showed significant long-term memory two or four weeks after training but WT and KO mice did not differ in this regard. A group of well-trained mice were given training on novel odors in sessions limited to 20–80 trials. Memory of these problems at two day delays did not differ between WT and KO mice. Tests using ethyl acetate demonstrated that WT and KO mice had similar odor detection thresholds.  相似文献   
756.
Social scientific investigation into the religiospiritual characteristics of American Indians rarely includes analysis of quantitative data. After reviewing information from ethnographic and autobiographical sources, we present analyses of data from a large, population-based sample of two tribes (n = 3,084). We examine salience of belief in three traditions: aboriginal, Christian, and Native American Church. We then investigate patterns in sociodemographic subgroups, determining the significant correlates of salience with other variables controlled. Finally, we examine frequency with which respondents assign high salience to only one tradition (exclusivity) or multiple traditions (nonexclusivity), again investigating subgroup variations. This first detailed, statistical portrait of American Indian religious and spiritual lives links work on tribal ethnic identity to theoretical work on America's "religious marketplace." Results may also inform social/behavioral interventions that incorporate religiospiritual elements.  相似文献   
757.
Common Representations of Abstract Quantities   总被引:2,自引:0,他引:2  
ABSTRACT— Representations of abstract quantities such as time and number are essential for survival. A number of studies have revealed that both humans and nonhuman animals are able to nonverbally estimate time and number; striking similarities in the behavioral data suggest a common magnitude-representation system shared across species. It is unclear, however, whether these representations provide animals with a true concept of time and number, as posited by Gallistel and Gelman (2000) . In this article, we review the prominent cognitive and neurobiological models of timing and counting and explore the current evidence suggesting that nonhuman animals represent these quantities in a modality-independent (i.e., abstract) and ordered manner. Avenues for future research in the area of temporal and mathematical cognition are also discussed.  相似文献   
758.
The current study involved a comprehensive comparative examination of overt and relational aggression and victimization across multiple perspectives in the school setting (peers, teachers, observers in the lunchroom, self-report). Patterns of results involving sociometic status, ethnicity and gender were explored among 4th graders, with particular emphasis on girls. Controversial and rejected children were perceived as higher on both forms of aggression than other status groups, but only rejected children were reported as victims. Both European American and African American girls showed a greater tendency toward relational aggression and victimization than overt aggression or victimization. Results indicated negative outcomes associated with both relational and overt victimization and especially overt aggression for the target girl sample. Poorer adjustment and a socially unskillful behavioral profile were found to be associated with these three behaviors. However, relational aggression did not evidence a similar negative relation to adjustment nor was it related to many of the behaviors examined in the current study. Implications of these results are discussed.  相似文献   
759.
Prospective links among reactive aggression, proactive aggression, and victimization by peers were investigated in a longitudinal sample of 238 preadolescents (aged 10-13 years, 52% girls). No predictive links were found between victimization and either type of aggression among girls. Among boys, reactive aggression predicted higher future levels of victimization but was not itself affected by prior victimization. In contrast, boys' proactive aggression predicted lower levels of future victimization and was itself reduced by their prior victimization. Finally, reactive aggression predicted later proactive aggression for both boys and girls. These results are explained in terms of the different reactions that others have to proactive and reactive aggression, the different functions they serve, and to the different types of aggression that are common for boys and girls.  相似文献   
760.
Personality in domestic cats   总被引:1,自引:0,他引:1  
Personality ratings of 196 cats were made by their owners using a 5-point Likert scale anchored by 1: not at all and 5: a great deal with 12 items: timid, friendly, curious, sociable, obedient, clever, protective, active, independent, aggressive, bad-tempered, and emotional. A principal components analysis with varimax rotation identified three intepretable components. Component I had high loadings by active, clever, curious, and sociable. Component II had high loadings by emotional, friendly, and protective, Component III by aggressive and bad-tempered, and Component IV by timid. Sex was not associated with any component, but age showed a weak negative correlation with Component I. Older animals were rated less social and curious than younger animals.  相似文献   
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