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241.
In the cooperative breeding system of cotton-top tamarin (TCB; Saguinus oedipus) males gain weight during the last months of pregnancy of their partners as a way to cope with energy costs of reproduction. This phenomenon was described only in humans as a symptom of . As after infants' birth, TCB male and female helpers lose weight, the same as fathers do, it might be expected that previously, they also gain weight. In 8 groups of TCB, we explored body weight changes of the three categories of individuals, in periods of six months, under three different reproductive conditions: control (no pregnancy and without offspring), pregnancy (pregnancy and without offspring), and raising (with offspring). We found that across pregnancy, TCBs increase their weight in the last trimester of that period while across breeding TCBs reduce their weight in the first trimester. Expectant males and also helpers could be preparing during pregnancy in relation to the weight losses they experience when raising their young.  相似文献   
242.
The aim of this paper is to use an integrative approach to identify the main correlates and/or predictors at different levels (personal, psychosocial, occupational and outside the workplace) of the burnout dimensions. The sample consists of 813 university professors. Results from statistical analyses show that there are, indeed, both common and specific predictors for the different facets of the syndrome. Specifically, while social support and optimism are selected to confirm all manifestations of burnout, other factors (work hours per week, time in the profession, hardiness, Type A behavioural pattern, life events, daily hassles) do increase the emergence of differential profiles. Lastly, findings are discussed and the main conclusions are presented.  相似文献   
243.
The aim of current article was the adaptation and validation of the Adolescents' Perceived Collective Family Efficacy Scale (EFCP/A) in the Spanish context. The sample includes 486 adolescents. Psychometric properties of the EFCP/A were examined with exploratory factor analysis, item analysis and reliability. Construct validity was examined by means of correlations with parental relationships (PBI). The correlations with drug use (tobacco, alcohol, cannabis) and coping strategies were also examined. Results supported the unidimensionality and reliability of the EFCP/A scale in the Spanish context. As hypothesised, adolescents' beliefs in collective family efficacy are highly correlated with the quality of their paternal and maternal relationships. Further, the adolescents who are convinced that their family is efficacious display more productive coping strategies and less drug use.  相似文献   
244.
245.
Test anxiety is a common behavior among students facing social pressure centered on mastery. Only a few studies have analyzed the relations between test anxiety, academic procrastination, personal and family variables and math grades. This work focus on the analysis of the impact of students' social-personal variables such as parents' education level, number of siblings and under-achievement by performing ANOVAs in two samples of 533 and 796 students from junior high-school. Corroborating the findings in other studies, the data stress that test anxiety is higher in girls and decreases when students' parents have higher educational levels, with the number of courses flunked, and when students' math grades were lower. Test anxiety and procrastination correlate positive and significantly. Findings are discussed and compared with those of previous researches. The implications for teaching practice are also analyzed.  相似文献   
246.
Taking into account the studies about the measure of sensitivity in magnitude estimation tasks, we analyze the three most common measures used in this topic: Pearson's product-moment correlation between the logarithm of the stimulus and the logarithm of the response (R), the exponent of Stevens' power function (K), and the measure "M" proposed by Garriga-Trillo. Using a sample of participants greater than usual in psychophysical studies (180 participants), we designed an experiment with two sets of stimuli with different stimulus ranges. In each of these sets, we used two kinds of stimuli (line segments and squares). Our conclusions were: (1) we rejected the use of K as a sensitivity measure because the results provided by this index were the opposite of those expected when we compared the two stimulus ranges. (2) We also rejected the use of M because this measure is a linear transformation of Kendall's coefficient of concordance. (3) Lastly, we suggest the mathematical transformation proposed by Fisher to achieve a normal distribution, and recommend this transformation as the best sensitivity measure.  相似文献   
247.
Snoeren ND  Seguí J  Hallé PA 《Cognition》2008,108(2):512-521
The present study investigated whether lexical access is affected by a regular phonological variation in connected speech: voice assimilation in French. Two associative priming experiments were conducted to determine whether strongly assimilated, potentially ambiguous word forms activate the conceptual representation of the underlying word. Would the ambiguous word form [sud] (either assimilated soute 'hold' or soude 'soda') facilitate "bagage" 'luggage', which is semantically related to soute but not to soude? In Experiment 1, words in either canonical or strongly assimilated form were presented as primes. Both forms primed their related target to the same extent. Potential lexical ambiguity did not modulate priming effects. In Experiment 2, the primes such as assimilated soute pronounced [sud] used in Experiment 1 were replaced with primes such as soude canonically pronounced [sud]. No semantic priming effect was obtained with these primes. Therefore, the effect observed for assimilated forms in Experiment 1 cannot be due to overall phonological proximity between canonical and assimilated forms. We propose that listeners must recover the intended words behind the assimilated forms through the exploitation of the remaining traces of the underlying form, however subtle these traces may be.  相似文献   
248.
Previous research has demonstrated the importance of distinguishing between positive (communion) and negative (unmitigated communion) characteristics when investigating the relation between traditional feminine gender roles and psychological adjustment. However, previous work has relied on cross-sectional analysis of self-reported unmitigated communion and self-reported emotional distress. The present series of studies was designed to address this limitation by using multiple methodologies to examine the relation between unmitigated communion (UC) and psychological adjustment. Study 1 examined the relation between self- and peer reports in a sample of 102 college students. Study 2 examined the relation between communion, UC, and adjustment in a community sample of 94 adults using a 10-year longitudinal design. Study 3 used a daily diary methodology to examine the relation between these constructs, social functioning, and depressed mood in a sample of 78 college women. Results from the three studies converged to demonstrate that unmitigated communion is an important factor that impacts negatively on the psychological adjustment of men and women.  相似文献   
249.
Hair analysis has been used to reflect long-term systemic exposure to exogenous drugs and toxins. Several studies have demonstrated the feasibility of measuring endogenous steroid hormones, e.g. cortisol, in hair. Recently, a study in macaques showed a significant increase in hair cortisol levels induced by stress. We explored whether hair cortisol levels may be used as a biomarker for long-term stress in humans. Patients with severe chronic pain, aged 18 years or older, receiving opioid treatment for at least one year were recruited. Controls were non-obese (body mass index, BMI < 30 mg/kg(2)) adults. The Perceived Stress Scale (PSS) questionnaire was used to assess perceived stress over the last 4 weeks. A hair sample was obtained from the vertex posterior. Cortisol was measured using an enzyme-linked immunosorbent assay. We included fifteen patients (nine females and six males) and 39 non-obese control subjects (20 females, 19 males). PSS scores (median and range) were significantly higher in chronic pain patients (24: 12-28) than in controls (12: 3-31)(P < 0.001). Hair cortisol contents (median and range) were significantly greater in chronic pain patients (83.1: 33.0-205 g/mg) than in controls (46.1: 27.2-200 pg/mg) (P < 0.01). We conclude that hair cortisol contents are increased in patients with major chronic stress. Measurement of cortisol levels in hair constitutes a novel biomarker of prolonged stress.  相似文献   
250.
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