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991.
A number of models of behaviour have been applied to contraception use including subjective expected utility theory and social cognition models. Whilst correlates of contraception use have been identified, the limitations of these models include their failure to consider either contextual factors or changes in contraception use over time. Researchers have called for integrated and dynamic models of contraception use, which can be related to the changing contraception use of individual women and can also be readily operationalised to explore within and between subject differences in contraception use. The present study therefore used a qualitative methodology to explore women's contraceptive histories and to enable women to define the issues from their perspectives, resulting in a model of contraception use that is firmly located within the context of their own lives and allows an investigation of the factors and processes involved in changes in contraception use/non-use over time. This model conceptualises the predictors of contraception use in terms of the meaning and importance of a range of social goals, perceptions of vulnerability and constraints on or facilitators of contraception. Further the dynamic nature of these factors is described and it is illustrated how these core components vary over time according to situation, experience, and new information. The paper outlines the relevance of the findings for different models of decision-making processes and highlights the way that the model addresses the limitations of previous approaches. 相似文献
992.
We developed a method for estimating the dollar utility of changes in job performance associated with illnesses and their treatments. Then we applied this method to predict, for each job in the economy, the difference in productivity costs associated with the illness of Seasonal Allergic Rhinitis (SAR) and that due to the difference between 2 commonly used treatments of SAR. The findings suggest that workers are 5% less productive when affected by SAR, and that when workers treat their SAR with desloratadine (a nonsedating antihistamine) instead of diphenhydramine (an over-the-counter 1st-generation antihistamine), they are 7% more productive, translating to a daily productivity cost differential between the 2 treatments of $11 per day, or $2.6 billion annually. The jobs most affected require high amounts of selective attention and perceptual speed (e.g., Aircraft Pilots and Flight Engineers, and those in the fields of manufacturing, security, and emergency response). 相似文献
993.
Adrienne Y. Lee Gary D. Bond Deborah C. Russell Jeremy Tost Carlo González Pamela S. Scarbrough 《Military psychology》2013,25(3):237-261
Antecedents to trust (propensity to trust, perceived trustworthiness) and trust behaviors were examined in relation to team performance in a complex eight-mission military peacekeeping simulation. Teams were colocated or distributed and stayed in the same or transferred to a different context at task transfer. In Experiment 1, an ability and competence factor accounted for most of the variance in perceived trustworthiness and greater perceptions of teammates' abilities/competences predicted posttransfer performance. One's perception of how others perceived one's ability/competence increased over missions. In Experiment 2, propensity to trust did not predict performance; however, trust in others' and one's own ability/competence and trust behaviors predicted performance. At task and/or context transfer, teams produced more monitoring and less cooperating language in their communication. 相似文献
994.
Alison M. Gomes Megan M. Spencer-Smith Rani K. Jacobs Lee Coleman Vicki A. Anderson 《Child neuropsychology》2013,19(4):392-403
Attention and social functioning and their interrelationships have not been routinely examined in children with early brain insult (EBI). This study aimed to describe attention and social functioning in children with two types of EBI: malformations of cortical development (MCD) and stroke. Children diagnosed with MCD (n?=?14, 6 males) or stroke (n?=?14, 8 males) aged 8 to 14 years (M?=?12 years 11 months) completed neuropsychological assessments to examine attention processes. Primary caregivers completed a questionnaire to assess executive components of children's attention and teachers completed a questionnaire to measure children's social functioning. Brain scans (MRI or CT) were coded by a pediatric neuroradiologist. Higher rates of impairments in attention and social function were found in children with EBI compared with normative expectations. Children with MCD experienced more global and clinically significant levels of impairment than children with stroke; though impairments were present in both groups. A strong association between executive components of attention and social function was observed. In addition, complex attention processes were associated with social function. The findings emphasize the reciprocity between attention, behavior and social outcomes, and the vulnerability of social function following EBI. 相似文献
995.
Nghia Trong Mai Koo-Hyun Chung Seung Ryoon Lee Dong Kil Shin Youn Young Earmme 《Philosophical Magazine Letters》2013,93(4):242-250
The work of adhesion between a polydimethylsiloxane (PDMS) elastomer film and a flat diamond tip was measured by instrumented indentation. The results showed that the apparent work of adhesion between the tip and the PDMS film increases with increasing dwell time and retreating velocity; on the other hand, the indentation depth has no significant effect on adhesion. The indentation experiment was analysed with viscoelastic finite element simulations with rate-dependent cohesive elements, from which the time evolution of adhesion was quantitatively implemented into a rate-dependent cohesive-zone law. 相似文献
996.
Ester I. Klimkeit Jason B. Mattingley Dianne M. Sheppard Paul Lee John L. Bradshaw 《Child neuropsychology》2013,19(2):153-173
Attention and executive functions were investigated in medicated and unmedicated children with ADHD combined type using a novel selective reaching task. This task involved responding as rapidly as possible to a target while at times having to ignore a distractor. Results indicated that unmedicated children with ADHD showed slow and inaccurate responding. Slow responding reflected problems at the stage of movement preparation but not movement execution. An attentional impairment, rather than a motor planning problem per se, appeared to underlie the slow movement preparation. Inaccurate responding reflected problems with response inhibition and selective attention, impulsivity, set-shifting, and difficulties in maintaining vigilance. Although medicated children with ADHD did not show slow movement preparation, they did show some response inaccuracy, resulting especially from impulsive responding.These findings suggest that ADHD is characterized by slow motor preparation (but not motor execution), and deficits in selective attention, vigilance, and executive functions. Preliminary results suggest that stimulant medication may resolve some of these motor, attentional and executive function deficits. 相似文献
997.
Abstract Transmission electron microscopy analyses of hot-pressed α-Sic deformed at 1600°C have shown the activation of the basal plane with glide dislocations dissociated into Shockley partials. Loop nucleations have been frequently observed along the dislocation lines and a climb mechanism is proposed to explain, the experimental analyses. 相似文献
998.
Changes in the structure and mechanical properties of Ti50Zr25Co25 melt-spun ribbons upon electrolytic hydrogenation have been investigated. Structural analyses of the as-spun ribbons revealed the sporadic presence of icosahedral (i) quasicrystalline short-range order (SRO) in the amorphous structure. Upon cathodic charging with hydrogen, the i-SRO vanished for a hydrogen content of about 21 at.% (hydrogen-to-metal atom ratio, H/M: 0.26), resulting in a fully amorphous structure. Simultaneously, the fracture strength was found to increase while the ribbons preserved their bending ductility. However, a significant reduction in the fracture strength and ductility of the ribbons was observed for hydrogen concentrations larger than 26 at.%. Variations in the mechanical stability are discussed based on a structure-property correlation. 相似文献
999.
Catherine J. Lutz-Zois Lee J. Dixon Alec M. Smidt Jackson A. Goodnight Cameron L. Gordon Leigh E. Ridings 《Personality and individual differences》2013
Jack’s (1991) theory of self-silencing was originally designed to explain higher rates of depression in women in comparison to men. However, research finding that men score equal or even higher than women on measures of self-silencing has lead theorists to speculate that self-silencing tendencies may be driven by different motivations and have different consequences for women versus men (Jack & Ali, 2010). Using a sample of 247 college students, we examined gender differences in the construct validity of the Silencing the Self Scale (STSS; Jack & Dill, 1992). We hypothesized that women would score higher on the Externalized Self-Perception subscale, but not the other three subscales. Gender differences in the relationship between the STSS subscales and theoretically-relevant constructs were also explored. The results indicated that women on average scored higher than men on the Externalized Self-Perception subscale, whereas men scored higher on the Care as Self-Sacrifice subscale. Further, there was a significant Gender × Care as Self-Sacrifice subscale interaction in the prediction of depression, such that this subscale was negatively correlated to depression in men, and uncorrelated in women. These results clarify how self-silencing might translate into different mental health outcomes for women and men. 相似文献
1000.