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971.
In the past years, the possible involvement of inflammation in the pathogenesis of dementia has been the subject of several investigations. However there are restricted data about the profile of the inflammatory and soluble proteins in well evaluated Alzheimer's disease (AD), vascular dementia (VD), mild cognitive impairment (MCI) and healthy controls. There are also no reliable data regarding the relationship between the overlapping protein levels and cognitive or functional decline. We measured levels of IL-1beta, IL-2, IL-6, IL-18, TNF-alpha, beta-Amlyloid 1-40 and alpha1-antichymotrypsin levels in plasma in groups of total 82 subjects with AD, MCI, VD and controls using enzyme-linked immunosorbent assay (ELISA) method. Our study samples showed high levels of proinflammatory cytokine levels (especially IL-18) in all patient groups but only high levels of alpha1-antichymotrypsine in VD patients compared to controls. There is no significant correlation between the laboratory and clinical variables except for a link between IL-1beta and NPI scores of AD. In conclusion, this study yielded evidence of some shared mechanisms underlying AD and VD and thus motivates further studies of inflammatory markers in various types of dementia and MCI.  相似文献   
972.
There is ample evidence for the existence of an association between sleeplessness and worry. Not much is known, however, concerning the nature of this relationship. Therefore, a study was conducted investigating the causal relationship between sleeplessness and nocturnal worry. A 2 x 2 (Worry x Induced sleeplessness) analysis of covariance design was used. The first factor consisted of a subject variable defined by scoring either high or low on a trait measure of worry (the Penn State Worry Questionnaire) and the second factor consisted of 300 mg caffeine or placebo. A total of 96 female undergraduate students participated. The dependent variables comprised measures of nocturnal worry (the Night-Time Thoughts Questionnaire) and subjective and objective sleep parameters. Overall, caffeine caused an increase in nocturnal worry and sleeplessness. A significant interaction effect occurred between Worry and Induced sleeplessness on one of the objective sleep parameters, but no other interaction effects were significant. The results suggest that worry may occur as an epiphenomenon of sleeplessness.  相似文献   
973.
Because youth gangs tend to cluster in disadvantaged neighborhoods, adolescents living in such neighborhoods are more likely to encounter opportunities to join youth gangs. However, in the face of these opportunities, not all adolescents respond in the same manner. Those with preexisting psychopathic tendencies might be especially likely to join. In this study, we tested whether a combination of individual propensity and facilitating neighborhood conditions amplifies the probabilities of youth gang affiliation. A subset of 3,522 adolescents was selected from a nationally representative, prospective sample of Canadian youth. Psychopathic tendencies (i.e., a combination of high hyperactivity, low anxiety, and low prosociality as compared to national norms) were assessed through parent reports, while neighborhood characteristics (i.e., concentrated economic disadvantage and residential instability) were derived from the 2001 Census of Canada. Our results indicated that neighborhood residential instability, but not neighborhood concentrated economic disadvantage, interacted with individual propensity to predict youth gang membership. Adolescents with preexisting psychopathic tendencies appeared especially vulnerable mainly if they were raised in residentially unstable neighborhoods.  相似文献   
974.
An experiment was conducted where experienced criminal investigators (N = 49) evaluated the testimony of a witness who either confirmed or disconfirmed the focal hypothesis in a homicide case. Participants' motivation to perpetuate the hypothesis was manipulated by varying the need for cognitive closure via time pressure. The hypothesis‐inconsistent witness was perceived as less reliable and credible, although its background and witnessing conditions were identical to those of the hypothesis‐consistent witness. While this asymmetrical skepticism was not moderated by time pressure, participants under high (vs. low) time pressure were less inclined to adjust their confidence in the hypothesis in line with the witness testimony. Discussion focuses on implications for criminal investigations and theoretical contributions to investigative psychology.  相似文献   
975.
The authors examined Swedish judges', lay judges', and police officers' beliefs about factors that may complicate or facilitate children's reports of sexual abuse. Participants (N = 562) rated potential complicating and facilitating factors and freely reported which criteria they considered important when assessing the reliability of child witnesses. The groups had similar opinions regarding which factors are complicating and facilitating. Furthermore, the groups tended to regard emotional factors as more complicating than cognitive factors. When freely reporting criteria that are important when assessing reliability, judges and police officers reported criteria pertaining mainly to the child, whereas lay judges reported mainly criteria pertaining mainly to the police interview. Results indicate that participants believe that children have the capacity to remember and report about abuse but are hindered in doing so by emotional factors. Results also suggest that police officers may underestimate their own influence on the reliability of children's reports.  相似文献   
976.
This paper reports two experiments conducted to examine priority effects and sex differences in object location memory. A new task of paired position-learning was designed, based on the A–B A–C paradigm, which was used in paired word learning. There were three different paired position-learning conditions: (1) positions of several different objects (B-objects and C-objects) around referent objects (A-objects) were learned in the A–B A–C position-learning condition, (2) positions of several different objects with no referent objects were learned in the 0–B 0–C position-learning condition, and (3) positions of identical objects (stars) with no referent objects were learned in the 0-star 0-star position-only condition. The results revealed a significant priority effect on performance in the A–B A–C and the 0–B 0–C position-learning conditions but not in the 0-star 0-star position-only condition. Contradictory results were obtained with respect to the sex variable: a female superiority effect on paired position learning was significant in Experiment 1, but this effect was not replicated in Experiment 2. In addition, an articulatory suppression task used in Experiment 2 had a significant effect on recall of different object positions but no effect on recall of identical object positions. This suggested that verbal encoding was not necessary for learning of positions of identical objects.  相似文献   
977.
The purpose of this study was to assess the relationships between perceived exertion (RPE) and plasma glucose concentrations or hunger feelings during a 1-hr. bicycle submaximal exercise after ingestion of pre-exercise test foods with a different glycemic index. Each of endurance-trained male triathletes ingested three different glycemic index (GI) foods (HighGI: glucose, LowGI: whole-wheat biscuit or water) throughout the 3 hr. before exercise at 80% maximal oxygen uptake (VO2 max). RPE values increased as a logarithmic function of time. This result is opposite to results obtained with longer exercise bouts up to 3 hr. duration. RPE and hunger ratings were not significantly different for the three test foods whatever the time. Moreover, RPE did not correlate with plasma glucose concentrations during exercise. Consequently, RPE did not depend on the GI of the pre-exercise test foods during a 1-hr. exercise at 80% VO2 max. Physiological and psychological factors other than glycemic index may have mediated the perceptual responses during a 1-hr. high-intensity exercise. It is possible that during endurance exercise of longer duration, the level of blood glucose mediates the intensity of peripheral exertional perceptions arising from active skeletal muscle during prolonged exercise.  相似文献   
978.
The present research investigated the role of two sources of psychological need satisfaction (inside and outside a passionate activity) as determinants of harmonious (HP) and obsessive (OP) passion. Four studies were carried out with different samples of young and middle‐aged adults (e.g., athletes, musicians; total N = 648). Different research designs (cross‐sectional, mixed, longitudinal) were also used. Results showed that only a rigid engagement in a passionate activity (OP) was predicted by low levels of need satisfaction outside the passionate activity (in an important life context or in life in general), whereas both OP and a more favorable and balanced type of passion, HP were positively predicted by need satisfaction inside the passionate activity. Further, OP led to negative outcomes, and HP predicted positive outcomes. These results suggest that OP may represent a form of compensatory striving for psychological need satisfaction. It appears important to consider two distinct sources of need satisfaction, inside and outside the passionate activity, when investigating determinants of optimal and less optimal forms of activity engagement.  相似文献   
979.
980.
The aim of the present randomized double‐blind placebo control trial was to investigate if vitamin D supplementation had an effect on vitamin D status, executive functioning and self‐perceived mental health in a group of Norwegian adolescents during winter time. Fifty adolescents were randomly assigned into an intervention group (vitamin D pearls) or a control group (placebo pearls). Before (pre‐test in December/January) and after (post‐test in April/May) the intervention period the participants were exposed to a test procedure, consisting of blood draw, completion of cognitive tests (Tower of Hanoi and Tower of London), and the Youth Self‐report version of the Child Behavior Checklist. Multivariate data analysis showed that participants with low vitamin D status scored worse on the Tower of London tests and the more difficult sub‐tasks on the Tower of Hanoi tests. They also had a tendency to report higher frequency of externalizing behavior problems and attention deficit. At pre‐test, the overall mean vitamin D status measured as 25‐hydroxy vitamin D was 42 nmol/L, defining deficiency (Intervention group = 44 nmol/L, Control group = 39 nmol/L). However, vitamin D supplementation caused a significant increase in vitamin D status resulting in a sufficient level in the Intervention group at post‐test (mean 62 nmol/L). The results also revealed that the intervention group improved their performance on the most demanding sub‐tasks on the ToH. Overall, the study indicates that vitamin D status in adolescents may be important for both executive functioning and mental health.  相似文献   
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