首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1036篇
  免费   78篇
  国内免费   1篇
  1115篇
  2024年   4篇
  2023年   7篇
  2022年   15篇
  2021年   29篇
  2020年   43篇
  2019年   59篇
  2018年   69篇
  2017年   66篇
  2016年   63篇
  2015年   45篇
  2014年   51篇
  2013年   127篇
  2012年   74篇
  2011年   81篇
  2010年   37篇
  2009年   31篇
  2008年   33篇
  2007年   32篇
  2006年   38篇
  2005年   32篇
  2004年   19篇
  2003年   23篇
  2002年   9篇
  2001年   7篇
  2000年   8篇
  1999年   4篇
  1998年   7篇
  1997年   8篇
  1996年   3篇
  1995年   6篇
  1994年   4篇
  1993年   2篇
  1992年   3篇
  1991年   5篇
  1990年   6篇
  1989年   6篇
  1987年   3篇
  1985年   4篇
  1984年   6篇
  1983年   5篇
  1982年   9篇
  1981年   5篇
  1980年   4篇
  1979年   6篇
  1978年   2篇
  1977年   2篇
  1976年   3篇
  1975年   2篇
  1973年   2篇
  1971年   2篇
排序方式: 共有1115条查询结果,搜索用时 0 毫秒
21.
Selective breeding of wild rats over many generations on the basis of low or high defensive threat and attack to human approach and contact has produced highly polarized “domesticated” and “wild-type” animals. Because the selection procedure selectively involves these two defense patterns, and these clearly differ in the two groups, it is of interest to determine if other, nonselected, defensive behaviors to threat stimuli also change. “Domesticated” and “wild-type” rats of the thirty-fifth generation were run in a fear defense test battery (F/DTB) to systematically evaluate defensive behaviors to a variety of present threat stimuli. “Domesticated” rats showed reduced avoidance and slower flight speed to an approaching experimenter, reduced jump/startle response to handelap and dorsal contact, less vocalization and boxing to vibrissae stimulation or to an anesthetized conspecific, and reduced defensiveness to an attempted pickup by the experimenter. These results indicate that selective bi-directional breeding for defensive threat and attack to human approach and contact produces group differences in a variety of defensive behaviors, and in defensiveness to stimuli other than those on which the selection was based. © 1994 Wiley-Liss, Inc.  相似文献   
22.
Adults' face processing may be specialized for the dimensions of young adult faces. For example, young and older adults exhibit increased accuracy in normality judgments and greater agreement in attractiveness ratings for young versus older adult faces. The present study was designed to examine whether there is a similar young adult face bias in facial age estimates. In Experiment 1, we created a face age continuum by morphing an averaged young adult face with an averaged older adult face in 5% increments, for a total of 21 faces ranging from 0 to 100% old. Young and older adults estimated facial age for three stimulus age categories [young (morphs 0–30%), middle‐aged (morphs 35–65%), and older adult (morphs 70–100%)]. Both age groups showed the least differentiation in age estimates for young adult faces, despite showing greater consensus across participants in estimates for young faces. In Experiment 2, young and older adults made age estimates for individual young and older adult identities. Both age groups were more accurate and showed greater consensus in age estimates for young faces. Collectively, these results provide evidence for a bias in processing young adult faces beyond that which is often observed in recognition and normality/attractiveness judgment tasks.  相似文献   
23.
Affective processing is one domain that remains relatively intact in healthy aging. Investigations into the neural responses associated with reward anticipation have revealed that older and younger adults recruit the same midbrain reward regions, but other evidence suggests this recruitment may differ depending on the valence (gain, loss) of the incentive cue. The goal of the current study was to examine functional covariance during gain and loss feedback in younger and healthy older adults. A group of 15 older adults (mean age = 68.5) and 16 younger adults (mean age = 25.4) completed a revised Monetary Incentive Delay task (rMID; Knutson, Westdorp, Kaiser, &; Hommer, 2000) while in the fMRI scanner. The rMID is a reaction time task where successful performance, either gaining a reward or avoiding a loss, is defined by hitting a button during the brief presentation of a visual target. Participants receive gain and loss anticipation cues before each trial and feedback after each trial with four possible outcomes: +$5.00, +0.00, -$5.00, and -Affective processing is one domain that remains relatively intact in healthy aging. Investigations into the neural responses associated with reward anticipation have revealed that older and younger adults recruit the same midbrain reward regions, but other evidence suggests this recruitment may differ depending on the valence (gain, loss) of the incentive cue. The goal of the current study was to examine functional covariance during gain and loss feedback in younger and healthy older adults. A group of 15 older adults (mean age = 68.5) and 16 younger adults (mean age = 25.4) completed a revised Monetary Incentive Delay task (rMID; Knutson, Westdorp, Kaiser, & Hommer, 2000) while in the fMRI scanner. The rMID is a reaction time task where successful performance, either gaining a reward or avoiding a loss, is defined by hitting a button during the brief presentation of a visual target. Participants receive gain and loss anticipation cues before each trial and feedback after each trial with four possible outcomes: +$5.00, +0.00, -$5.00, and -$0.00. Using seed-voxel partial least squares analyses, with seed voxels in the caudate and ventromedial prefrontal cortex, whole-brain functional covariance revealed that younger and older adults engage the same network of regions to support general feedback processing. However, older adults engaged two additional networks to support processing of negative feedback, gain_miss (+0), loss_miss (-$5), and loss_hit (?0), specifically. These findings are in line with theories of a positivity effect in aging and may have implications for reward-stimulus learning and decision making following performance-contingent negative feedback.  相似文献   
24.
This study assessed secondborn adolescents' perceptions of changes in the allocation of family resources following their firstborn siblings' departure from home after high school, and whether perceived changes were related to changes over 1 year in secondborns' academic functioning. Participants were secondborn siblings (mean age = 16.58, SD = 0.91) from 115 families in which the older sibling had left the family home in the previous year. Allocation of resources was measured via coded qualitative interviews. Most (77%) secondborns reported increases in at least one type of family resource (i.e., parental companionship, attention, material goods), and many reported an increase in multiple types of resources in the year following their older sibling's departure. Consistent with resource dilution theory, perceptions of increases in fathers' companionship, fathers' attention, and mothers' companionship were related to improvements over time in secondborns' academic functioning.  相似文献   
25.
Our analyses examined whether reserve capacity factors would explain the relationship between socioeconomic status (SES) and symptoms of depression/anxiety in patients with systemic lupus erythematosus (SLE). We assessed disease activity, depression/anxiety symptoms, and intrapersonal and interpersonal reserve capacity measures in 128 patients with SLE. Multiple meditational analyses revealed that intrapersonal and interpersonal psychosocial aspects of reserve capacity fully mediated the relationship between SES and depression/anxiety. Lower SES was indirectly associated with higher symptoms of depression and anxiety through the effects of psychosocial resilience. Interventions aimed at improving modifiable reserve capacity variables, such as self-esteem and optimism, may improve anxious/depressive symptomatology in patients with SLE.  相似文献   
26.
Individuals identified as at high risk of developing Hereditary Diffuse Gastric Cancer (HDGC) are advised to undergo prophylactic surgery - have their stomach removed - in their early twenties. Research with (older) cancer patients who undergo gastrectomy for curative reasons suggests that gastric resection has a number of physical and psychosocial sequelae. Because it is difficult to extrapolate the findings of studies of older cancer patients to younger healthy patients who are considering prophylactic total gastrectomy (PTG), the aim of this qualitative interview study was to determine the psychosocial implications of undergoing prophylactic surgery to manage genetic risk. Fourteen men and 13 women from the UK’s Familial Gastric Cancer study who had undergone PTG were invited to participate in qualitative interviews. Most reported that undergoing surgery and convalescence was easier than anticipated. There was evidence that age affected experiences of PTG, with younger patients tending to report faster recovery times and more transient aftereffects. All saw the benefits of risk reduction as outweighing the costs of surgery. Surgery was described as having a range of physical impacts (disrupted appetite, weight loss, fatigue, GI symptoms) that had related psychological, social and economic implications. Those considering PTG need to be aware that its impact on quality of life is difficult to predict and negative sequelae may be ongoing for some individuals.  相似文献   
27.
Maternal stress, anxiety, and depression are associated with ineffective parenting strategies for families of children with Autism Spectrum Disorders (ASD). We present the use of Parent-Child Interaction Therapy (PCIT) with three mother-child dyads to reduce maternal stress, anxiety, and depression and child disruptive behavior in children with ASD. Results included increases in positive parenting skills, and decreases in maternal anxiety, depression, and stress, as well as child behavior problems. PCIT is a promising alternative to more intensive and costly interventions, both at reducing disruptive behaviors and improving maternal health. Implications of PCIT for dyads affected by ASD are discussed.  相似文献   
28.
This study investigated how personal goals influence age differences in episodic future thinking. Research suggests that personal goals change with age and like autobiographical memory, future thinking is thought to be organised and impacted by personal goals. It was hypothesised that cueing older adults with age-relevant goals should modulate age differences in episodic details and may also influence phenomenological characteristics of imagined scenarios. Healthy younger and older adults completed the Future Thinking Interview [Addis, D. R., Wong, A. T., & Schacter, D. L. (2008). Age-related changes in the episodic simulation of future events. Psychological Science, 19(1), 33–41. doi:10.1111/j.1467-9280.2008.02043.x] adapted to activate age-appropriate goals. Narratives were scored with an established protocol to obtain objective measures of episodic and semantic details. Subjective features such as emotionality and personal significance showed age differences as a function of goal domain while other features (e.g., vividness) were unaffected. However, consistent with prior reports, older adults produced fewer episodic details than younger adults and this was not modulated by goal domain. The results do not indicate that goal activation affects level of episodic detail. With respect to phenomenological aspects of future thinking, however, younger adults show more sensitivity to goal activation, compared with older adults.  相似文献   
29.
Deliberate self-harm (DSH) is a strong predictor of suicide in schizophrenia. The aim of this review was to identify risk factors for DSH in schizophrenia. This systematic review of the international literature examined cohort and case-control studies of patients with schizophrenia or related diagnoses that reported DSH as an outcome. Studies were identified by searching electronic databases and reference lists, and by consulting international experts. Fourteen studies met the eligibility criteria. Of the 29 variables examined by two or more studies, five (past or recent suicidal ideation, previous DSH, past depressive episode, drug abuse or dependence, and higher mean number of psychiatric admissions) were associated with an increased risk of DSH, and one (unemployment) was associated with a reduced risk. Schizophrenic patients with these risk factors need careful follow-up and monitoring, with treatment of any associated comorbid depression or drug abuse. Large, prospective studies of DSH in schizophrenia are needed to further define risk factors and to build on the findings of this review.  相似文献   
30.
Age differences in bias in conditional probability judgments were investigated based on predictions derived from the Minerva-Decision Making model (M. R. P. Dougherty, C. F. Gettys, & E. E. Ogden, 1999), a global matching model of likelihood judgment. In this study, 248 younger and older adults completed frequency judgment and conditional probability judgment tasks. Age differences in the frequency judgment task are interpreted as an age-related deficit in memory encoding. Older adults' stronger biases in the probability judgment task point to age differences in criterion setting. Age-related biases were eliminated when age groups were equated on memory encoding by means of study time manipulation. The authors conclude that older adults' stronger judgment biases are a function of memory impairment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号