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   1581篇
  免费   93篇
  1674篇
  2023年   9篇
  2022年   14篇
  2021年   17篇
  2020年   34篇
  2019年   47篇
  2018年   71篇
  2017年   68篇
  2016年   67篇
  2015年   35篇
  2014年   65篇
  2013年   155篇
  2012年   84篇
  2011年   78篇
  2010年   47篇
  2009年   51篇
  2008年   67篇
  2007年   76篇
  2006年   52篇
  2005年   69篇
  2004年   58篇
  2003年   55篇
  2002年   61篇
  2001年   32篇
  2000年   29篇
  1999年   21篇
  1998年   26篇
  1997年   13篇
  1996年   19篇
  1995年   16篇
  1994年   18篇
  1993年   8篇
  1992年   14篇
  1991年   12篇
  1990年   15篇
  1989年   14篇
  1988年   17篇
  1987年   11篇
  1986年   10篇
  1985年   12篇
  1984年   10篇
  1983年   5篇
  1982年   8篇
  1981年   6篇
  1980年   8篇
  1979年   6篇
  1978年   12篇
  1976年   8篇
  1973年   5篇
  1972年   5篇
  1969年   6篇
排序方式: 共有1674条查询结果,搜索用时 0 毫秒
991.
The development of visual attention is a key component of cognitive functioning in infancy and childhood. By the time children in poverty reach school, deficits in attention are readily apparent; however, when these attention delays manifest is unknown. The current study tested attention longitudinally at 6, 9 and 12 months in infants from high‐socio‐economic status (SES) and low‐SES families. Infants were tested in a free play attention task in both simple and complex conditions, and two measures each of attention and inattention were scored. High‐SES infants showed greater attention overall and greater increases in attention when the stimuli were more complex. Low‐SES infants showed higher inattention than their high‐SES peers at all ages and were less likely to modulate their attention on the basis of stimulus complexity. Thus, by 6 months of age, low‐income infants already show deficits in attention. Results are discussed in terms of adaptability, implications for social development and attention interventions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
992.
In this article we describe our approach to understanding wrongdoing in medical research and practice, which involves the statistical analysis of coded data from a large set of published cases. We focus on understanding the environmental factors that predict the kind and the severity of wrongdoing in medicine. Through review of empirical and theoretical literature, consultation with experts, the application of criminological theory, and ongoing analysis of our first 60 cases, we hypothesize that 10 contextual features of the medical environment (including financial rewards, oversight failures, and patients belonging to vulnerable groups) may contribute to professional wrongdoing. We define each variable, examine data supporting our hypothesis, and present a brief case synopsis from our study that illustrates the potential influence of the variable. Finally, we discuss limitations of the resulting framework and directions for future research.  相似文献   
993.
This case study examines the failure of top management at Putnam to exercise ethical behavior in the face of their clear knowledge of corruption in the company. Market timing by employees was expressly forbidden by Putnam. Six employees, including two portfolio managers, repeatedly engaged in market timing activities from 1998 to 2003, garnering over a million dollars in personal profit. The CEO and key senior executives had factual knowledge of the abuses. Management failed to stop the abuses or to discipline those involved until faced with charges from government regulators. By failing to do so, top management breached ethical duties to its shareholders and inflicted serious damage on the organization. The end results of top management's failure to address ethical violations were significant outflow of assets from Putnam's funds, payment of penalties, and loss of trust among investors. This case raises awareness about ethical issues surrounding mutual fund trading practices and the impact that top management can have on the ethical behavior of employees.  相似文献   
994.
Pakistan is a densely populated country in South Asia with a high burden of genetic disease. A dearth of medical genetic services exists and master’s level trained genetic counselors (GCs) are currently not a part of the healthcare system. This study is the first to determine the views of Pakistani medical doctors (MDs) towards genetic counseling services in Pakistan, including what manner a master’s level genetic counselor might be incorporated into the healthcare system. Fifty-one MDs practicing in the city of Karachi completed a self-administered survey of twenty questions. Of the 49 respondents who answered a specific question, 100 % (49/49) felt that they would refer at least some, if not all, of their relevant patients to a genetic’s clinic if one existed in Karachi. Overall, the respondents showed a positive attitude towards the provision of genetic counseling services as a part of the healthcare system of Pakistan. Some of the proposed roles identified specifically for GCs included: explaining how Down syndrome occurs (66.1 %), discussing genes associated with breast cancer (77.4 %), and explaining the inheritance pattern of β-thalassemia (65.5 %). In contrast, the review of medical and family history and discussion of medical procedures such as ultrasound and amniocentesis were typically seen as the role of a physician. A majority of the respondents (98 %) were in favor of premarital carrier screening for thalassemia and would refer patients to a GC to describe the importance of carrier screening (84.3 %) and to help explain carrier screening results (94.1 %). Many respondents selected GCs as the ideal provider of education and support for people with inherited conditions (43.8 %), followed by specialist MDs (26 %) and general physicians (22.9 %). Considering the high burden of genetic disease in the country, we encourage the development of genetic counseling services in Pakistan.  相似文献   
995.
This study examined the effects of parental depression symptoms, economic disadvantage, and parenting behaviors in 180 children and adolescents of depressed parents (ages 9–15 years-old). Analyses revealed that while parental depression symptoms, economic disadvantage, and disrupted parenting behaviors were related to children’s internalizing and externalizing symptoms, disrupted parenting (e.g., intrusive, neglectful parenting) accounted for the association of parental depressive symptoms and economic disadvantage with children’s symptoms. This study provides evidence that disrupted parenting may be a common or shared process through which both parental depression and economic disadvantage are associated with children’s internalizing and externalizing problems.  相似文献   
996.
Research has linked sexual assault, substance use, and sexually transmitted infection (STI) risk in women. Sexual assault by means of verbal sexual coercion (VSC) is more common than sexual assault by means of physical tactics, but VSC is rarely assessed independently. In addition, past work has established global connections among substance use, sexual assault history, and STI risk; however, assessing substance use during sexual behavior is less common. This study examined the relations among VSC, STI risk behavior, and substance use and attitudes. We hypothesized that women with larger numbers of VSC experiences would report more frequent sexual risk behaviors and substance use and attitudes. Participants with larger numbers of VSC experiences reported larger numbers of anal sex partners, more frequent penile–vaginal sex and sexual activity after substance use, and stronger sex-related alcohol expectancies. These findings suggest that VSC is associated with higher levels of STI risk in women.  相似文献   
997.
ABSTRACT

We investigated the word-list-learning performance of younger and older adults over 4 consecutive days at different times of day to study age-related differences in consistency of performance over time and the influence of circadian variation on performance. Eighteen younger (M age, 23.4 years) and 18 older (M age, 73.3 years) men and women participated. The start time of testing alternated between morning and early evening across the 4 days of testing. On each test day, participants learned a different list of 15 unrelated words over four learning trials. As expected, younger adults performed better than older adults on immediate recall, delayed recall, and recognition. Contrary to our expectations, time of day did not significantly influence recall or recognition performance in either the older or younger adults. Older adults did show a greater incidence of false memory (i.e., previously learned list intrusions in free recall and false alarms in recognition) than younger adults. Older adults also exhibited greater intra-individual performance variability on the measures of false memory across test days. This variability was not related to circadian variation. False memory and variability of performance have both been linked to frontal systems dysfunction. The findings presented here are consistent with the notion that changes in cognition with aging in part reflect age-related decline in frontal lobe function.  相似文献   
998.
999.
Implicit prejudices are social preferences that exist outside of conscious awareness or control. In this review, we summarize evidence for three mechanisms that influence the expression of implicit prejudice: associative change, contextual change, and change in control over implicit prejudice. We then review the evidence (or lack thereof) for answers to five open issues in implicit prejudice reduction research: (1) what shows effectiveness in real‐world application; (2) what doesn't work for implicit prejudice reduction; (3) what interventions produce long‐term changes in implicit prejudice; (4) measurement diversity in implicit prejudice reduction research; and (5) the relationship between implicit prejudice and behavior. Addressing these issues provides an agenda for clarifying the conditions and implications of reducing implicit prejudice.  相似文献   
1000.
The authors asked 55 second-generation Chinese American adolescents (M age = 16.8 years) and 58 European American adolescents (M age = 17.0 years) to complete self-report measures of stress levels, use of coping strategies, psychological outcomes, and grades. Chinese American adolescents reported higher levels of everyday life event stress (e.g., stress from schoolwork), more depression, and higher grade point averages. Problem-focused and avoidance-coping behaviors moderated the effect of stress on negative adjustment for Chinese American youth but not for European American youth. Path analysis showed that avoidance coping behavior partially mediated the stress-to-negative adjustment relationship for Chinese American youth but not for European American youth. Stress was associated with lower grades in Chinese American youth, but the authors found no association for European American youth.  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