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921.
The effect of prior deformation on mechanical behavior as a function of size is investigated for body-centered cubic (bcc) molybdenum (Mo) pillars. Experiments were performed using focused ion beam (FIB) manufactured [0 0 1] and [2 3 5] Mo micro/nanopillars, which were compressed, re-FIB machined, and compressed again. Unlike in bulk materials, pre-straining has a negligible effect on stress–strain behavior of the pillars, suggesting that dislocation storage does not occur in small-scale bcc specimens. The prevailing mechanism behind the size effect is attributed to dislocation nucleation mechanisms.  相似文献   
922.
923.
Prior research has shown that reduced autobiographical memory specificity predicts an increase in post-traumatic stress severity in traumatised individuals. Studies have also demonstrated that reduced memory specificity predicts later symptoms of depression after pregnancy-related life stress. So far, no reported studies have tested the predictive value of memory specificity at the onset of a potentially traumatic situation. Therefore the aim of the present study was to investigate whether prenatal memory specificity would predict post-traumatic stress after complicated pregnancy. The results demonstrate that women who retrieved fewer specific memories with a pregnancy-related content to positive cues during pregnancy (i.e., directly after hospitalisation) reported more post-traumatic stress 6 weeks after giving birth. This relationship remained significant after controlling for variables that were related to both baseline autobiographical memory specificity and later post-traumatic stress. A similar pattern was found for depression symptomatology, even when somatic symptoms were excluded from the analyses. Taken together, these data suggest that the relationship of memory specificity with later depression can be generalised to post-traumatic stress symptoms.  相似文献   
924.
Abstract

While most patients with bulimia nervosa are heterosexual women, a significant number of men with bulimia nervosa are gay males, suggesting that gay men, more than heterosexual men, may be at risk for developing eating disorders. This study compared the food-related attitudes and behaviors of heterosexual men and women in contrast with those of lesbians and gay men, attempting to find whether one's sexual orientation may contribute to differential risk. Two thousand employees were randomly selected from a large health care corporation, of whom 805 returned a completed questionnaire including Stunkard and Messick's (1985) Dietary Restraint and Disinhibition Scales. A stratified random sample was drawn to include demographically comparable groups of 25 lesbians, 50 gay men, 75 heterosexual women, and 75 heterosexual men. Women were less satisfied with their appearance at their present weight and expressed more restraint and more negative feelings after bingeing than did men. Heterosexual women were most dissatisfied with their weight, although heterosexual men were more objectively overweight. Gay men and heterosexual women were similar in disordered eating patterns and disinhibition, contrasting with lesbians and heterosexual men.  相似文献   
925.
926.
The United States Air Force Deployment Transition Center (DTC) operates a 2-day third-location decompression program that commenced operations during the summer of 2010 in Ramstein, Germany, with the aim to assist Air Force service members (AFSMs) who are returning from deployment as they prepare to reintegrate back into their home lives and work stations. The present study evaluated the impact of DTC attendance on later mental health outcomes. Because participants are not randomly assigned to attend the DTC, propensity score weighting was used to compare DTC participants (N = 1,573) to a weighted control group of AFSMs (N = 1,570) in the same job specialties who returned from deployment during the same time period. Rates of endorsement to items on the Postdeployment Health Reassessment were examined and compared, as were rates of mental health diagnoses from AFSMs’ official medical records. Key findings indicate that DTC participants reported lower levels of depressive and posttraumatic stress symptoms and lower levels of relationship conflict following return from deployment, as compared to weighted control participants. Mental health diagnostic rates were comparable for the 2 groups during the first 6 months following return from deployment. These findings suggest that participation in the DTC program had notable benefits for redeploying AFSMs and support the continued use of the program.  相似文献   
927.
Studies on the effects of acute bouts of cardiovascular exercise on cognitive performances show contradictory findings due to methodological differences (e.g., exercise intensity, cognitive function assessed, participants’ aerobic fitness level, etc.). The present study assessed the acute effect of exercise intensity on cognition while controlling for key methodological confounds. Thirty-seven participants (Mage = 23. 8 years; SD = 2.6) completed a computerized modified-Stroop task (involving denomination, inhibition and switching conditions) while pedalling at 40%, 60% and 80% of their peak power output (PPO). Results showed that in the switching condition of the task, error rates increased as a function of exercise intensity (from 60% to 80% of PPO) in all participants and that lower fit individuals showed increased reaction time variability. This suggests that acute bouts of cardiovascular exercise can momentarily alter executive control and increase performance instability in lower fit individuals.  相似文献   
928.
This study examined the relationship between emotional intelligence (EI) and the stress process. Participants (N = 126) completed an ability-based measure of EI and then engaged with two stressors. We assessed stressor appraisals, emotions, and physiological stress responses over time. We expected that higher EI would facilitate stress responses in the direction of challenge, rather than threat. As expected, EI facets were related to lower threat appraisals, more modest declines in positive affect, less negative affect and challenge physiological responses to stress. However, findings differed for men and women. This study provides predictive validity that EI facilitates stress resilience.  相似文献   
929.
We investigated the relationship between parents' empathic responses prior to their children undergoing cancer treatment procedures and children's pain/distress during the procedures. We hypothesized: (1) parents' empathic distress would be positively associated with children's pain/distress, (2) parents' empathic concern would be negatively associated with children's pain/distress; and (3) parents' enduring dispositions and social support would be associated with their empathic responses. Parents completed: (1) measures of dispositions and perceived social support several weeks before their children underwent the procedures, and (2) state measures of empathic distress and empathic concern just before the procedures. Empathic distress was positively associated with children's pain; empathic concern was negatively associated with children's pain/distress. Predictions about dispositions and social support were also substantially confirmed.  相似文献   
930.
Across two experiments, we studied a phenomenon akin to choice blindness in the context of participants' accounts of their own history of norm‐violating behaviors. In Experiment 1, N = 67 participants filled in an 18‐item questionnaire about their history of norm‐violating behaviors (QHNVB). Subsequently, they were questioned about four of their answers, two of which had covertly been manipulated by the experimenter. Of the 134 manipulations, 20 (14.9%) remained undetected concurrently and 13 were accepted in retrospect (9.7%). In Experiment 2 (N = 37), we inserted a one‐week interval between questionnaire and interview. Twenty‐seven (36.5%) of the 74 manipulations remained undetected concurrently and three were accepted in retrospect (8.1%). Data obtained in a four‐week follow‐up indicated that our manipulations may have long‐term effects on participants' perception of their own history of norm‐violating behaviors. Implications for the occurrence of false confessions during the course of an interrogation are discussed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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