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Why are European Jews migrating to Israel in significant numbers? Israeli leaders and popular press reports suggest that incidents of antisemitism have reached such high levels across Europe, even in fully democratic countries, that Jews are leaving once again to escape persecution and violence. Others suggest that Jews are migrating for the same reasons other migrants do: for greater economic opportunity. Until now, we have had no way of weighing the relative merit of these claims, hampered by the absence of reliable comparative data on antisemitism in Europe. Leveraging a new dataset compiled by the author, this study tests these competing hypotheses and finds that European Jews migrate because of greater economic opportunity in Israel. While concerns about antisemitism in Europe are at record highs and more Jews are considering moving to Israel than ever before in the post-war era, so far most Jewish migration is to take advantage of better economic opportunities in Israel.  相似文献   
155.
The IIFF model of organ donation holds that the simultaneous presence of four factors directly influence donor registration: (1) immediate and complete registration opportunity (ICRO), (2) information, (3) focused engagement, and (4) favorable activation. Two field experiments examined the impact of an ICRO on organ donation registration. In Study 1, participants were at town halls where they knew organ donation was to be discussed. Registration cards were distributed and then collected at the end of the session in half of the town halls. For the other half, participants were asked to mail in completed cards. In three US cities, participants given an ICRO registered at a significantly greater rate (z?=?4.865, p?相似文献   
156.
Only recently has the mental health community recognized the applicability of diagnostic criteria for posttraumatic stress disorder (PTSD) in children and adolescents, including a consideration of specific age-related features. This paper provides a current review of the literature on PTSD pertaining to children and adolescents. Following a discussion of issues on diagnostic criteria and assessment of this affective disorder in this population, there is an overview of the existing literature on prevalence, comorbidity, risk factors, parental and family factors, and issues of gender and age of onset. The remainder of the paper focuses on the range of traumatic stressors in children and adolescents that can result in PTSD, including natural or human disasters, war and violence, chronic or life-threatening medical conditions, community violence and the witnessing of traumatic events, and physical and/or sexual abuse and other forms of interpersonal violence. Throughout the paper, there is an emphasis on the importance of considering developmental factors. Finally, implications of the existing literature for future areas of research are addressed.  相似文献   
157.
National Guard (NG) soldiers returning from deployments in Iraq and Afghanistan were surveyed at 6 and 12 months following their return (N = 970). The overall prevalence of suicide risk at 6 and 12 months following their return was assessed, as were changes in suicide risk among soldiers initially at high or low risk. Factors associated with changes in risk were assessed. The percentage of NG soldiers with high suicide risk increased from 6.8% at 6 months to 9.2% at 12 months (odds ratio = 1.7, p = .02). In the 882 soldiers initially at low risk, 5.9% (52/882) became high risk at 12 months; in the 64 soldiers initially at high risk, 46.9% (30/64) became low risk at 12 months. Initial levels of depressive symptoms were predictive of changing to high risk; this association appeared to be partially explained by soldier reports of increased search in the meaning in life and higher levels of perceived stress. Because suicide risk increases over the first 12 months, continued risk assessments during this time period should be considered. Supporting soldiers to find meaning in their life after deployment and enhancing their capacity to cope with perceived stress may help prevent increases in suicide risk over time.  相似文献   
158.
Distances tend to be underperceived in virtual environments (VEs) by up to 50%, whereas distances tend to be perceived accurately in the real world. Previous work has shown that allowing participants to interact with the VE while receiving continual visual feedback can reduce this underperception. Judgments of virtual object size have been used to measure whether this improvement is due to the rescaling of perceived space, but there is disagreement within the literature as to whether judgments of object size benefit from interaction with feedback. This study contributes to that discussion by employing a more natural measure of object size. We also examined whether any improvement in virtual distance perception was limited to the space used for interaction (1–5 m) or extended beyond (7–11 m). The results indicated that object size judgments do benefit from interaction with the VE, and that this benefit extends to distances beyond the explored space.  相似文献   
159.
Pigeon concept formation: successive and simultaneous acquisition   总被引:2,自引:0,他引:2       下载免费PDF全文
Pigeons were trained to discriminate the presence of one or more human forms in displays projected on a panel above the response key. This task was mastered, although imperfectly, with successive and with simultaneous presentations of positive and negative instances. The course of acquisition of the discrimination was similar for the two training procedures. Animals were able to transfer the discrimination from the successive to the simultaneous situation. Various tests were carried out to control for artifactual cues on which the discrimination might have been based. The discrimination was maintained when new displays were presented, when reinforcement was omitted, and when displays were inverted 180°. Animals were also able to discriminate between pairs of displays that were identical, except that one member of the pair contained a human form. The research extends the techniques used by Herrnstein and Loveland (1964), and confirms their finding that pigeons can master the concept of “person-present” in a visual display.  相似文献   
160.
Silent reading fluency has received limited attention in the school-based literatures across the past decade. We fill this gap by examining both oral and silent reading fluency and their relation to overall abilities in reading comprehension in fourth-grade students. Lower-level reading skills (word reading, rapid automatic naming) and vocabulary were included in structural equation models in order to determine their impact on reading fluency and comprehension. Results suggested that oral and silent reading fluency represent separate constructs, but only oral reading fluency contributed to reading comprehension. Vocabulary was found to contribute uniquely to comprehension even after controlling for reading fluency.  相似文献   
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