全文获取类型
收费全文 | 5610篇 |
免费 | 298篇 |
国内免费 | 1篇 |
专业分类
5909篇 |
出版年
2024年 | 15篇 |
2023年 | 81篇 |
2022年 | 65篇 |
2021年 | 109篇 |
2020年 | 145篇 |
2019年 | 183篇 |
2018年 | 258篇 |
2017年 | 272篇 |
2016年 | 260篇 |
2015年 | 185篇 |
2014年 | 192篇 |
2013年 | 687篇 |
2012年 | 399篇 |
2011年 | 412篇 |
2010年 | 237篇 |
2009年 | 141篇 |
2008年 | 325篇 |
2007年 | 265篇 |
2006年 | 238篇 |
2005年 | 193篇 |
2004年 | 179篇 |
2003年 | 157篇 |
2002年 | 119篇 |
2001年 | 69篇 |
2000年 | 82篇 |
1999年 | 59篇 |
1998年 | 36篇 |
1997年 | 31篇 |
1996年 | 27篇 |
1995年 | 20篇 |
1994年 | 13篇 |
1993年 | 24篇 |
1992年 | 24篇 |
1991年 | 32篇 |
1990年 | 40篇 |
1989年 | 24篇 |
1988年 | 32篇 |
1987年 | 25篇 |
1986年 | 25篇 |
1985年 | 24篇 |
1984年 | 24篇 |
1983年 | 19篇 |
1982年 | 10篇 |
1979年 | 14篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1974年 | 10篇 |
1971年 | 9篇 |
1968年 | 8篇 |
1966年 | 9篇 |
排序方式: 共有5909条查询结果,搜索用时 15 毫秒
161.
Eunjeong?KangEmail author Ana María?Brannan Craig Anne?Heflinger 《Journal of child and family studies》2005,14(1):43-56
The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders. 相似文献
162.
Research that uses simple response time tasks and neuroimaging has emphasized that attentional preparation based on temporal
expectancy modulates processing at motor levels. A novel approach was taken to study whether the temporal orienting of attention
can also modulate perceptual processing. A temporal-cuing paradigm was used together with a rapid serial visual presentation
procedure, in order to maximize the processing demands of perceptual analysis. Signal detection theory was applied in order
to examine whether temporal orienting affects processes related to perceptual sensitivity or to response criterion (indexed
byďand beta measures, respectively). If temporal orienting implies perceptual preparation, we would expect to observe an increase
in perceptual sensitivity (ď) when a target appeared at expected, rather than unexpected, time intervals. Indeed, our behavioral results opened the possibility
that focusing attention on time intervals not only enhances motor processing, as has been shown by previous research, but
also might improve perceptual processing. 相似文献
163.
Koch I 《Psychonomic bulletin & review》2005,12(1):107-112
Many studies of task switching have found that a prolonged preparation time reduces switch costs. An alternative manipulation
of task preparation is based on sequential task predictability, rather than preparation time. In Experiments 1 and 2 of the
present study, participants performed explicitly instructed task sequences (i.e., AABB) and were then transferred to a random
sequence. The observed benefit of predictability-based task preparation was not switch specific. In Experiment 3, the participants
changed from random to predictable tasks. The observed predictability benefit again was not switch specific. The data thus
suggest that task switching does not necessarily require a switch-specific reconfiguration process. Rather, task-specific
control processes may be needed in both task switches and repetitions. 相似文献
164.
The aim of this study is to analyze how the length of time a patient spends in an Intensive Care Unit (ICU) affects close relatives, with regard to specific clinical variables of personality, family relationships and fear of death. The study group consisted of 57 relatives of seriously ill patients admitted to the ICU of "Virgen del Rocío" Rehabilitation and Trauma Hospital (Seville, Spain). The instruments applied were: a psychosocial questionnaire, clinical analysis questionnaire, family environment scale and fear of death scale. The relatives of patients admitted to ICU obtained higher scores in hypochondria, suicidal depression, agitation, anxious depression, guilt-resentment, paranoia, psychasthenia, psychological maladjustment and self-expression, and less in fear of their own death, as when compared to interviews with the same relatives 4 years later. The length of time a patient spent in the ICU influenced relatives in some clinical variables of personality, family relationships and fear of death 相似文献
165.
Twenty-four detoxified opiate addicts were randomized to an experimental group and a control group to evaluate efficacy of a group cue-exposure treatment to reduce or extinguish classically conditioned responses to drug-related stimuli. Assessment included psychophysiological responses (skin temperature, skin conductance level--SCL--, and heart rate) to a videotape and subjective measures (subjective craving, positive and negative affect) before and after the videotape. The experimental group received a group cue-exposure program to drug-related stimuli that comprised twelve treatment sessions administered three times weekly. The treatment program significantly reduced conditioned responses to drug-related stimuli, as measured by SCL and positive affect. 相似文献
166.
Over the last years several European patents were opposed for protecting technology violating the morality requirement under
Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments
introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability
requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is
to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years.
An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights
and Patents,” held in Warsaw, Poland on 23–24 April, 2004. 相似文献
167.
Nanotechnology — A new field of ethical inquiry? 总被引:2,自引:0,他引:2
Grunwald A 《Science and engineering ethics》2005,11(2):187-201
Parallel to the public discussion on the benefits and risks of nanotechnology, a debate on the ethics of nanotechnology has
begun. It has been postulated that a new “nano-ethics” is necessary. In this debate, the — positive as well as negative —
visionary and speculative innovations which are brought into connection with nanotechnology stand in the foreground. In this
contribution, an attempt is made to discover new ethical aspects of nanotechnology in a more systematic manner than has been
the case. It turns out that there are hardly any completely new ethical aspects raised by nanotechnology. It is much rather
primarily a case of gradual shifts of emphasis and of relevance in questions which, in principle, are already known and which
give reason for ethical discussions on nanotechnology. In a certain manner, structurally novel ethical aspects arise through
the important role played by visions in the public discourse. New questions are also posed by the fact that previously separate
lines of ethical reflection converge in the field of nanotechnology. The proposal of an independent “nano-ethics”, however,
seems exaggerated. 相似文献
168.
169.
Weak phantasmata have a decisive and specifically transcendental function in our everyday perception. This paper provides several different arguments for this claim based on evidence from both empirical psychology and phenomenology.I would like to express my gratitude to Bill McKenna for his help with the English text and his critical remarks. This paper was presented in the Cork Roundtable for Philosophy in March 2003, at University College, Cork, and I would like to thank Julia Jansen, Tony O’Connor and the other participants for their constructive critique. 相似文献
170.
The aims of the present review are to apply a recent risk factor approach (H. C. Kraemer et al., 1997) to putative risk factors for eating disorders, to order these along a timeline, and to deduce general taxonomic questions. Putative risk factors were classified according to risk factor type, outcome (anorexia nervosa, bulimia nervosa, binge-eating disorder, full vs. partial syndromes), and additional factor characteristics (specificity, potency, need for replication). Few of the putative risk factors were reported to precede the onset of the disorder. Many factors were general risk factors; only few differentiated between the 3 eating disorder syndromes. Common risk factors from longitudinal and cross-sectional studies were gender, ethnicity, early childhood eating and gastrointestinal problems, elevated weight and shape concerns, negative self-evaluation, sexual abuse and other adverse experiences, and general psychiatric morbidity. Suggestions are made for the conceptualization of future risk factor studies. 相似文献