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   6899篇
  免费   351篇
  国内免费   1篇
  7251篇
  2024年   16篇
  2023年   73篇
  2022年   67篇
  2021年   122篇
  2020年   151篇
  2019年   210篇
  2018年   266篇
  2017年   266篇
  2016年   301篇
  2015年   216篇
  2014年   223篇
  2013年   823篇
  2012年   387篇
  2011年   405篇
  2010年   236篇
  2009年   226篇
  2008年   335篇
  2007年   283篇
  2006年   236篇
  2005年   244篇
  2004年   241篇
  2003年   244篇
  2002年   177篇
  2001年   122篇
  2000年   135篇
  1999年   92篇
  1998年   72篇
  1997年   61篇
  1996年   50篇
  1995年   43篇
  1994年   31篇
  1993年   37篇
  1992年   64篇
  1991年   58篇
  1990年   80篇
  1989年   60篇
  1988年   63篇
  1987年   39篇
  1986年   51篇
  1985年   47篇
  1984年   43篇
  1983年   39篇
  1982年   30篇
  1981年   19篇
  1980年   17篇
  1979年   25篇
  1978年   26篇
  1977年   20篇
  1974年   15篇
  1972年   14篇
排序方式: 共有7251条查询结果,搜索用时 15 毫秒
801.
Abstract

In the present study, effects of a health education (INFO) and a PsychoEducational Prevention (INFO + PEP) Programme were Investigated in three hospitals. These programmes were offered to groups of coronary heart disease (CHD) patients and their partners alter discharge from hospital. The INFO was offered to 127 CHD patients in addition to FIT (i.e. standard medical care and physical training). The PEP was offered to 90 Patients in, addition to the INFO and FIT. A control group of 122 patients received only FIT. The INFO and the PEP consisted of four weekly two-hour group sessions each. In addition, the PEP was followed by seven telephone follow-up contacts.

On average, patients improved their lifestyles during the first three months. Between three and twelve months an extra improvement was found for eating habits, whereas there was a relapse for smoking and a sedentary lifestyle. In the short term, angina pectoris and a longer period of heart complaints were parallelled with a decrease in the risk of maintaining unhealthy eating habits, whereas in the long term a longer period of heart complaints a younger age and unemployment predicted a lower risk of maintaining unhealthy eating habits In the short term living with a partner and in the long term female gender were predictive of continued smoking behaviour In the short term, older age, a first CABG and a specific hospital setting decreased the risk of a continued sedentary lifestyle.

The FIT + INFO + PEP had a favourable short-term effect on eating habits. For smoking and a sedentary lifestyle, however, there were negative effects. In the short term patients in the FIT +INFO and those in the FIT +INFO+PEP had significantly more problems in quitting a sedentary lifestyle than those in the FIT intervention in the long term, patients in the FIT + INFO had significantly more problems in stopping smoking compared to these in the FIT.  相似文献   
802.
The aim of this study was to test whether maternal smoking-specific communication and parental smoking related to smoking cognitions (i.e. attitude, self-efficacy and social norm) derived from the Theory of Planned Behaviour in association with smoking onset during preadolescence. A total of 1478 pairs of mothers and children participated (mean age: 10.11; standard deviation?=?0.78). Structural equation models in Mplus were used to examine whether smoking-specific communication influences children's smoking cognitions, which in turn, affect smoking onset. A positive association was found between pro-smoking attitudes and smoking onset. Smoking-specific communication and parental smoking were related to smoking cognitions. Specifically, frequency of communication was negatively associated with pro-smoking attitudes, social norms of mother and best friend. Quality of communication related negatively to pro-smoking attitudes and positively to self-efficacy and norms of friends. Parental smoking was positively associated with pro-smoking attitudes and norms of mother and (best) friends. Additionally, more frequent communication and higher levels of parental smoking were associated with higher smoking onset. In conclusion, smoking-specific communication and parental smoking were associated with smoking cognitions and smoking onset. Already during preadolescence, parents contribute to shaping the smoking cognitions of their children, which may be predictive of smoking later in life.  相似文献   
803.
Emotional eating, the tendency to eat when experiencing negative affect, is prevalent in morbid obesity and may indicate that ways to deal with emotions are disturbed. Our aim was to compare emotion processing and regulation between 102 women with morbid obesity who apply for bariatric surgery and 102 women from the general population (control group) and to examine in the group with morbid obesity the association of emotion processing and regulation with emotional eating. The group with morbid obesity reported higher scores on difficulty identifying feelings (alexithymia, p?=?0.002) and suppression of emotions (p?=?0.003) than the control group. In the women with morbid obesity, more negative affect and a higher difficulty identifying feelings were correlated with more emotional eating (r?=?0.36 and r?=?0.35, p?<?0.001). Our study suggests that negative emotions and unhealthy emotion processing may play a role in emotional eating, and it indicates the possible relevance of emotion processing and emotional regulation as initiating or perpetuating mechanisms in morbid obesity.  相似文献   
804.
Contents     
Up to one third of the epilepsy population consists of children with cryptogenic localization related epilepsy (CLRE). Unfortunately, the effect of CLRE on the development is still unclear. Behavioral and academic problems have been reported, but no conclusive study concerning the impact of CLRE on neuropsychological functioning is yet published.

This study was a systematic cross-sectional open clinical and nonrandomized investigation, which included 68 children with CLRE. Several neuropsychological tests were analyzed and age-related normative values were used as reference. Differences between CLRE and reference values were tested with Paired-Samples t-tests. Z scores were computed to compare the different neuropsychological tests and to inspect whether a characteristic neuropsychological profile exists for CLRE. The Independent-Samples t-test was used to explore which epilepsy factors (seizure type, seizure frequency, age at onset, duration of epilepsy, and drug load) were influencing the cognitive profile of CLRE.

There seems to be a characteristic cognitive profile for children with CLRE; children with CLRE experience cognitive difficulties on a wide range of areas—in particular, alertness, mental speed, and memory. Seizure type, seizure frequency, duration of epilepsy, and drug load do not influence this neuropsychological profile. Age at onset was an important risk factor; the earlier the age at onset, the worse the cognitive performance. In spite of the influence of age at onset, the revealed profile can be seen as a stable, independent of temporary factors, neuropsychological profile for children with CLRE.  相似文献   
805.
Stressful life events can result into declined memory performance at later age. One hypothesis suggests that stress affects the hippocampus, a brain area important for memory functioning. This study explored a potential relationship between the number of negative stressful life events and hippocampus-dependent declarative but not hippocampus-independent procedural memory performance in a community sample of 255 children, aged 6–12 years. The findings revealed that negative stressful life events were negatively related to verbal declarative memory, but not to nonverbal declarative and procedural memory. The memory impairments could not be accounted for by attention and sleep disturbances, and parenting characteristics as perceived by the child did not influence the vulnerability for the stress-related memory impairments. These findings provide further insight into the deleterious effects of negative stressful life events on learning in school-aged children.  相似文献   
806.
Visuospatial working memory (VSWM) and visual perception were examined in two groups aged 11–13, one with children displaying symptoms of nonverbal learning disability (NLD) (n = 18) and the other a control group without learning disabilities (n = 18). The two groups were matched for general verbal abilities, age, gender, and socioeconomic level. The children were presented with VSWM tests involving visual and spatial-simultaneous processes, and also with a classical visual illusion, a classical ambiguous figure, as well as visual perception tests specifically devised for the present study. Results revealed that performance of children at risk of NLD was worse than controls in some VSWM and in visual perception tests without memory involvement; these latter required comparisons of visual stimuli and locations in space with distractors. Moreover, the two groups differed in perceiving the classical ambiguous figure. Findings are discussed in the light of both theoretical and clinical implications.  相似文献   
807.
On a gambling task that models real-life decision making, children between ages 7 and 12 perform like patients with bilateral lesions of the ventromedial prefrontal cortex (VMPFC), opting for choices that yield high immediate gains in spite of higher future losses (Crone &; Van der Molen, 2004 Crone, E. A. and Van der Molen, M. W. 2004. Developmental changes in decision-making: Performance on a gambling task previously shown to rely on ventromedial prefrontal cortex. Developmental Neuropsychology, 25(3): 251279. [PUBMED][INFOTRIEVE][CROSSREF][Taylor &; Francis Online], [Web of Science ®] [Google Scholar]). The current study set out to characterize developmental changes in decision making by varying task complexity and punishment frequency. Three age groups (7–9 years, 10–12 years, 13–15 years) performed two versions of a computerized variant of the original Iowa gambling task. Task complexity was manipulated by varying the number of choices participants could make. Punishment frequency was manipulated by varying the frequency of delayed punishment. Results showed a developmental increase in the sensitivity to future consequences, which was present only when the punishment was presented infrequently. These results could not be explained by differential sensitivity to task complexity, hypersensitivity to reward, or failure to switch response set after receiving punishment. There was a general pattern of boys outperforming girls by making more advantageous choices over the course of the task. In conclusion, 7–12-year-old children—like VMPFC patients—appear myopic about the future except when the potential for future punishment is high.  相似文献   
808.
The devitrification process of Zr46.75Ti8.25Cu7.5Ni10Be27.5 metallic glass during annealing in the supercooled liquid region has been studied by conventional, high-resolution and analytical transmission electron microscopy (TEM). Two kinds of particle appear during devitrification: quasicrystals and crystalline precipitates. Nanoanalysis with energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy reveal that quasicrystals are Be free, while the crystallites have the ZrBe2 hexagonal structure. These experiments confirm the key role of Be during devitrification. They also indicate that quasicrystals can form in the system Zr–Ti–Cu–Ni (without Be), as further evidenced by direct synthesis and an in situ neutron diffraction investigation, according to the chemical composition deduced from the TEM analysis.  相似文献   
809.
Human sensitivity for social cues is exquisite, as illustrated by the ease with which simplified point-light movements invoke social and emotional responses. Compared to faces, these biological motion stimuli only recently started to be used to explore questions regarding social cognition and anxiety. We presented human point-light walkers that could be perceived as facing towards or facing away from the observer, and tested whether participants with high social anxiety would perceive these bistable stimuli differently, because this type of stimuli has particular relevance for them. The results showed that observers with high social anxiety tended to see walkers as facing away more frequently than those with low social anxiety. This may mean that high socially anxious observers are biased towards the more positive perceptual alternative because they are motivated to protect themselves against threatening social experiences, but we also explore alternative explanations. The findings are in line with the evidence for a positivity bias in perception, also called wishful seeing, but in contrast with the attentional negativity bias often found in social anxiety. We discuss reasons for this divergence and possible limitations of the current study.  相似文献   
810.
This study investigated the psychosocial well-being of an indigenous cultural community in South Africa, using a sequential explanatory mixed-methods design. Data on life satisfaction and emotional, social and psychological well-being were collected from 521 local residents (48% female) of Ndumo in KwaZulu-Natal, South Africa using the Satisfaction-with-Life Scale and Mental Health Continuum. In addition, interviews were conducted with 20 Ndumo residents (35% female). Findings revealed that community members had above-average levels of psychosocial well-being and exhibited significant resilience towards countering socio-economic under-resourcing, including poverty and unemployment. The community resources found to aid resilient living included being able to live off the land, a pleasant climate, personal safety, hope for a better future, and instrumental, material, and social support from philanthropic organisations.  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