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   15651篇
  免费   361篇
  国内免费   191篇
  2012年   1428篇
  2011年   1633篇
  2010年   391篇
  2009年   182篇
  2008年   1295篇
  2007年   1267篇
  2006年   1155篇
  2005年   971篇
  2004年   836篇
  2003年   827篇
  2002年   746篇
  2001年   479篇
  2000年   669篇
  1999年   287篇
  1998年   88篇
  1997年   61篇
  1996年   80篇
  1995年   49篇
  1994年   86篇
  1993年   122篇
  1992年   106篇
  1991年   107篇
  1990年   99篇
  1989年   105篇
  1988年   125篇
  1987年   132篇
  1986年   94篇
  1985年   129篇
  1984年   128篇
  1983年   145篇
  1982年   108篇
  1981年   100篇
  1980年   84篇
  1979年   92篇
  1978年   84篇
  1966年   48篇
  1965年   134篇
  1964年   105篇
  1963年   126篇
  1962年   54篇
  1958年   183篇
  1957年   152篇
  1956年   143篇
  1955年   91篇
  1954年   92篇
  1953年   93篇
  1952年   75篇
  1951年   78篇
  1950年   58篇
  1949年   43篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Lawyers are often called upon by their older clients to draft contracts, make up wills or powers of attorney, or provide other forms of legal advice or service. With the increasing numbers of older people in the population, the numbers of older clients for legal practitioners is likely to increase. Older people are also at increased risk for impaired cognitive processes that can affect their ability to make reasoned judgements in civil contracts and other legal arrangements. Here we report on the results of a survey of 302 Australian solicitors as to their experience and practices in determining the capacity of older clients to make legal decisions. The responses, reflecting a 20.7% return rate, showed a wide range of experience in conducting capacity assessments, with a mean of 15.7 years (SD = 10.59). There was a very wide range of practices in determining capacity with no consensus. The most frequent form of questions older clients were asked related to personal and family history. Less than one-quarter asked for the rationale of the decision: the most appropriate form of question in the literature. The results suggest a need for further training of solicitors in the assessment of the capacity of older clients to make legal decisions.  相似文献   
942.
There is evidence that disturbances in central serotonin (5-HT) function have a role in impulsive aggression, violence, and criminality. A deletion/insertion polymorphism within the 5-HT transporter (5-HTT) promoter gene (5-HTT gene-linked polymorphic region, 5-HTTLPR) is thought to be associated with several psychopathological phenotypes related to disturbed impulse control, anxiety and depression. This study examined the association of the 5-HTTLPR with violent behavior in a sample of 153 male Caucasians referred for a forensic psychiatric examination. We found a significant excess of the short (s) allele and the s/s genotype in patients characterized by recurrent and overt physical violent behavior. This genetic variance explained 5% of the variance of violent behavior. When controlled for the impact of several psychopathologies related to violent behavior, this association was observed in individuals with a history of childhood attention deficit/hyperactivity disorder (ADHD)-related symptoms, but not presenting with personality disorder or increased impulsiveness. In conclusion, the results (i). suggest an association between serotonergic dysfunction and violent behavior, (ii). provide evidence for an-at least partial-genetic regulation of violent behavior in a subgroup of male offenders, and (iii). suggest a significant role for 5-HT transporter functionality for violent behavior.  相似文献   
943.
Previous studies have established an associative deficit hypothesis (Naveh-Benjamin, 2000), which attributes part of older adults' deficient episodic memory performance to their difficulty in creating cohesive episodes. In this article, the authors further evaluate this hypothesis, using ecologically relevant materials. Young and old participants studied name-face pairs and were then tested on their recognition memory for the names, faces, and the name-face pairs. The results extend the conditions under which older adults exhibit an associative deficit. They also show that reduced attentional resources are not the sole mediator of this deficit.  相似文献   
944.
Prey might assess that risk level estimated in the first encounter with a predator was fixed in subsequent responses, whereas prey using flexible behavior would track short-term changes in risk. The authors examined, in the field, refuge use of Iberian rock lizards (Lacerta monticola) after simulated predator attacks and tested (a) how risk was assessed when multiple sources of risk were present simultaneously, (b) how short-term changes in risk level of successive attacks affected refuge use, and (c) whether the interval between attacks was important, insofar as attacks were considered to be coming from the same or different predators. Results suggest that lizards have a flexible estimate of risk that is based on multiple sources and flexibly dependent on previous estimates.  相似文献   
945.
Two striking contrasts currently exist in the sentence processing literature. First, whereas adult readers rely heavily on lexical information in the generation of syntactic alternatives, adult listeners in world-situated eye-gaze studies appear to allow referential evidence to override strong countervailing lexical biases (Tanenhaus, Spivey-Knowlton, Eberhard, and Sedivy, 1995). Second, in contrast to adults, children in similar listening studies fail to use this referential information and appear to rely exclusively on verb biases or perhaps syntactically based parsing principles (Trueswell, Sekerina, Hill, and Logrip, 1999). We explore these contrasts by fully crossing verb bias and referential manipulations in a study using the eye-gaze listening technique with adults (Experiment 1) and five-year-olds (Experiment 2). Results indicate that adults combine lexical and referential information to determine syntactic choice. Children rely exclusively on verb bias in their ultimate interpretation. However, their eye movements reveal an emerging sensitivity to referential constraints. The observed changes in information use over ontogenetic time best support a constraint-based lexicalist account of parsing development, which posits that highly reliable cues to structure, like lexical biases, will emerge earlier during development and more robustly than less reliable cues.  相似文献   
946.
Three experiments are reported that examined conceptual negative priming effects in children 5 to 12 years of age. Experiment 1 used a negative priming variant of a flanker task requiring the naming of a central color blob flanked by irrelevant distractors. Experiment 2 used a negative priming variant of the Stroop color-word task. Experiment 3 used a same-different matching task with novel 3-D shapes. Results revealed significant and equivalent magnitudes of negative priming across the tested age groups for all 3 tasks. It is concluded that the inhibitory mechanism underlying conceptual (i.e., identity or semantic) negative priming in visual selective attention tasks is intact in young children. Because the findings and conclusions diverge from the developmental literature on negative priming, the authors attempt to reconcile the contradictions by pinning down the reasons for the discrepancies.  相似文献   
947.
With a sample of 1,630 sixth-grade students from 77 classrooms, the authors used hierarchical linear modeling to examine how ethnicity within context and classroom social disorder influenced the association between peer victimization and social-psychological adjustment (loneliness and social anxiety). Victimized students in classrooms where many classmates shared their ethnicity reported feeling the most loneliness and social anxiety. Additionally, classroom-level social disorder served as a moderator such that the association between victimization and anxiety was stronger in classrooms with low social disorder. Both findings were interpreted as evidence that problem behavior deviating from what is perceived as normative in a particular context heightens maladjustment. The authors discuss implications for studying ethnicity and classroom behavioral norms as context variables in peer relations.  相似文献   
948.
Data regarding individual differences in children's regulation, emotionality, quality of socioemotional functioning, and shyness were obtained from teachers and peers for 112 Indonesian 6th graders. Similar data (plus parents' reports) also were collected when these children were in 3rd grade. For boys, regulation and low negative emotionality generally predicted positive socioemotional functioning (e.g., social skills, adjustment, prosocial tendencies and peer liking, sympathy) within and across time and across reporters, even at the follow-up when initial levels of regulation or negative emotionality were controlled. For girls, relations were obtained primarily for concurrent teacher reports, probably because girls tended to be fairly well regulated and socially competent and variability in their scores was relatively low. Shyness for both sexes tended to be associated with concurrent measures of low regulation, high negative emotionality, and low quality of social competence.  相似文献   
949.
Findings are presented of a study of families created through surrogacy arrangements. Forty-two surrogacy families were compared with 51 egg-donation families and 80 natural-conception families on standardized interview and questionnaire measures of the psychological well-being of the parents, the quality of parent-child relationships, and infant temperament. The differences that were identified between the surrogacy families and the other family types indicated greater psychological well-being and adaptation to parenthood by mothers and fathers of children born through surrogacy arrangements than by the natural-conception parents.  相似文献   
950.
One component of individual risk for alcoholism may involve cognitive vulnerabilities prodromal to alcoholism onset. This prospective study of 198 boys followed between 3 and 14 years of age evaluated neurocognitive functioning across three groups who varied in familial risk for future alcoholism. Measures of intelligence, reward-response, and a battery of neuropsychological executive and cognitive inhibitory measures were used. Executive functioning weaknesses were greater in families with alcoholism but no antisocial comorbidity. IQ and reward-response weaknesses were associated with familial antisocial alcoholism. Executive function effects were clearest for response inhibition, response speed, and symbol-digit modalities. Results suggest that executive deficits are not part of the highest risk, antisocial pathway to alcoholism but that some executive function weaknesses may contribute to a secondary risk pathway.  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