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231.
Symmetry, averageness, and sexual dimorphism (femininity in female faces, masculinity in male faces) are attractive in faces. Many have suggested that preferences for these traits may be adaptations for identifying healthy mates. If they are, then the traits should be honest indicators of health and their attractiveness should result from their healthy appearance. Much research has focused on whether these traits honestly signal health. Here we focused on whether the appeal of these traits results from their healthy appearance. Specifically, we tested whether the attractiveness of symmetry, averageness, and sexual dimorphism is reduced or eliminated when perceived health is controlled, in two large samples of Western faces and a large sample of Japanese faces. The appeal of symmetric faces was largely due to their healthy appearance, with most associations between symmetry and attractiveness eliminated when perceived health was controlled. A healthy appearance also contributed to the appeal of averageness and femininity in female faces and masculinity in male faces, although it did not fully explain their appeal. These results show that perceptions of attractiveness are sensitive to a healthy appearance, and are consistent with the hypothesis that preferences may be adaptations for mate choice.  相似文献   
232.
TRAP-1 is a mitochondrial heat shock protein (HSP), recently identified in Saos-2 osteosarcoma cells adapted to mild oxidative stress induced by diethylmaleate (DEM). TRAP-1 mRNA expression is increased in DEM-adapted cells as well as in tumor cells resistant to 5-fluorouracil and to platin derivatives. Since a strong decrease of TRAP-1 protein levels, upon cisplatin treatment, is observed only in controls but not in the DEM-adapted counterpart, a possible role for this protein in the development of resistant phenotypes could be hypothesized. To characterize the protective role of TRAP-1 against oxidative stress and apoptosis, stable transfectants were generated and characterized for their response to different stress types. These stable clones expressing constitutively high TRAP-1 levels: (i) are more resistant to H2O2-induced DNA damage and to apoptosis by cisplatin; (ii) contain higher reduced glutathione (GSH) levels than control cells; and (iii) do not release the apoptosis-inducing factor into the nucleus upon cisplatin treatment. Furthermore, high TRAP-1 levels interfere with caspase 3 activation. These results confirm the anti-apoptotic role of TRAP-1, and suggest that increased expression of this mitochondrial HSP in DEM-adapted and chemoresistant cells could be part of a pro-survival signaling pathway aimed to evade toxic effects of oxidants and anticancer drugs.  相似文献   
233.
Several driving simulators have been developed which range in complexity from PC based driving tasks to advanced "real world" simulators. The AusEd driving simulator is a PC based task, which was designed to be conducive to and test for driver fatigue. This paper describes the AusEd driving simulator in detail, including the technical requirements, hardware, screen and file outputs, and analysis software. Some aspects of the test are standardized, while others can be modified to suit the experimental situation. The AusEd driving simulator is sensitive to performance decrement from driver fatigue in the laboratory setting, potentially making it useful as a laboratory or office based test for driver fatigue risk management. However, more research is still needed to correlate laboratory based simulator performance with real world driving performance and outcomes.  相似文献   
234.
Children's negative characteristics are thought to be a factor in evoking hostile parenting responses. This can result in genotype/environment correlations (rGE) in which children's heritable traits influence the parenting they experience. We did genetic analyses on 292 mothers' self-reported hostile-reactive behaviors toward each of their twins at 5, 18 and 30 months. Finding heritability for a parenting behavior analyzed as a child phenotype is evidence of rGE correlation. The heritability of maternal behavior was modest (29% at 5 months, 0% at 18 months, and 25% at 30 months) and longitudinal analyses indicated that genetic factors at 5 and 30 months were uncorrelated. Common environment factors, probably reflecting characteristics of the mothers, were the main source of variance at the three ages and were highly correlated through time. We concluded that children's heritable characteristics evoked maternal negative response at specific times, but were not responsible for the stability of maternal hostility from infancy to toddlerhood.  相似文献   
235.
236.
A three-neuron network (a central pattern generator [CPG]) is both sufficient and necessary to generate aerial respiratory behavior in the pond snail, Lymnaea stagnalis. Aerial respiratory behavior is abolished following a specific nerve crush that results in axotomy to one of the three CPG neurons, RPeD1. Functional regeneration of the crushed neurite occurs within 10 days, allowing aerial respiratory behavior to be restored. Functional regeneration does not occur if the connective is cut rather than crushed. In unaxotomized snails, aerial respiratory behavior can be operantly conditioned, and following memory consolidation, long-term memory (LTM) persists for at least 2 weeks. We used the Lymnaea model system to determine (1) If in naive animals axotomy and the subsequent regeneration result in a nervous system that is competent to mediate associative learning and LTM, and (2) if LTM survives RPeD1 axotomy and the subsequent regenerative process. We show here that (1) A regenerated nervous system is competent to mediate associative memory and LTM, and (2) LTM survives axotomy and the subsequent regenerative process.  相似文献   
237.
Fifty-five insomniacs, 60 years or above, participated in a behavioral treatment program, comparing two interventions (sleep hygiene+stimulus control vs sleep hygiene+relaxation tape). Half of the subjects were randomized to a waiting-list condition prior to treatment. No significant changes were observed during the waiting-list period. During the treatment period however, the subjects improved on several sleep parameters, and treatment gains were maintained at a 6-month follow-up. The effects of treatment were greater for nocturnal measures (e.g. sleep onset latency and total sleep time) as compared to daytime measures (e.g. life satisfaction, daytime alertness) and not-targeted behavior (medication use). There were no differences in treatment effects for the two interventions.  相似文献   
238.
The authors performed a meta-analysis based on 169 conditions, gathered from 80 laboratory studies, to estimate the validity of the Guilty Knowledge Test (GKT) with the electrodermal measure. The overall average effect size was 1.55, but there were considerable variations among studies. In particular, mock-crime studies produced the highest average effect size (2.09). Three additional moderators were identified: Motivational instructions, deceptive ("no") verbal responses, and the use of at least 5 questions were associated with enhanced validity. Finally, a set of 10 studies that best approximated applications of the GKT under optimal conditions produced an average effect size of 3.12. The authors discuss factors that might limit the generalizability of these results and recommend further research of the GKT in realistic setups.  相似文献   
239.
We present two experiments in which we measured lexical decision latencies and errors to words with few or many orthographic neighbors (ie., Coltheart's N). The main goal of the study was to examine whether or not the neighborhood size effect in a lexical decision task could be affected by the exposure duration of the stimulus item (unlimited vs. limited time exposure, 150 msec plus a backward mask) and the type of decision involved in the task (yes/no vs. go/no-go lexical decision tasks). In the yes/no task, the results showed a facilitative neighborhood size effect for low frequency that did not interact with exposure duration (Experiment 1). In contrast, in the go/no-go task (in this task, participants are instructed to respond as quickly as they can when a word is presented and not to respond if a nonword is presented), the neighborhood size effect for low-frequency words (and for nonwords) was greater under limited viewing time (Experiment 2). In addition, the word frequency effect was greater in the go/no-go task than in the yes/no task, replicating Hino and Lupker (1998, 2000). The results were interpreted in terms of the interaction of decision and lexical factors in visual-word recognition.  相似文献   
240.
To assess the factorial validity of the 27-item Conners' Parent Rating Scale-Revised: Short Form (CPRS-R:S; Conners, 1997), 100 (50%) male and 100 (50%) female psychiatric outpatients between 5 and 16 years old were rated by a parent. A confirmatory factor analysis of the 18 item ratings from the CPRS-R:S Oppositional, Cognitive Problems, and Hyperactivity scales provided only tentative support for scoring these scales as Conners (1997) recommended. However, an exploratory principal-axis factor analysis with all 27 item ratings found 2 dimensions: 1 dimension was composed of the 6 items in the Oppositional scale, and other dimension contained the remaining 21 items. An attention deficit hyperactivity disorder (ADHD) Total Symptoms scale was constructed by summing the ratings for these 21 symptom ratings, and this scale was found to be as effective as the Hyperactivity scale was in discriminating between youth who were and were not eventually diagnosed with an ADHD. We discuss the results as providing an alternate way of scoring the CPRS-R:S to screen for an ADHD in child and adolescent psychiatric outpatients.  相似文献   
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