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   319篇
  免费   41篇
  国内免费   28篇
  2024年   1篇
  2023年   7篇
  2022年   7篇
  2021年   7篇
  2020年   7篇
  2019年   21篇
  2018年   23篇
  2017年   21篇
  2016年   18篇
  2015年   9篇
  2014年   22篇
  2013年   53篇
  2012年   13篇
  2011年   4篇
  2010年   7篇
  2009年   8篇
  2008年   8篇
  2007年   17篇
  2006年   13篇
  2005年   19篇
  2004年   15篇
  2003年   9篇
  2002年   6篇
  2001年   5篇
  2000年   4篇
  1999年   5篇
  1998年   4篇
  1997年   3篇
  1996年   5篇
  1995年   4篇
  1994年   4篇
  1993年   5篇
  1992年   3篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1987年   2篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1980年   4篇
  1979年   2篇
  1978年   1篇
  1977年   2篇
  1976年   4篇
  1975年   5篇
排序方式: 共有388条查询结果,搜索用时 15 毫秒
91.
This study examines thesentence processing ability of mild cognitive impairment (MCI) subtypes. In addition to standard MCI neuropsychological tests, an experimental approach was applied to assess language. 133 people (93 MCI/40 controls) participated in novel computerized sentence processing tasks. Results presented statistically significant differences between MCI/controls andMCI subtypes (ANOVA):(a) duration F(2,92) = 19.259,p < .001) in sentence construction; (b) correct answers (F(2, 89) = 8.560,p < .001) and duration (F2,89) = 15.525,p < .001)in text comprehension; (c) correct answers (F(2, 92) = 8.975,p < .001) andduration (F(2, 92) = 4.360,p = .016) in metaphoric sentences comprehension; (d) correct answers (F(2, 92) = 12.836,p < .001) andduration (F(2, 92) = 10.974,p < .001) in verb form generation. Subtle changes in MCIsubtypes could affect sentence processing and provide useful information for cognitive decline risk estimation and screening purposes.  相似文献   
92.
ABSTRACT

The discussion of migrants’ education focuses generally on whether and how host countries should educate their migrant populations, examining the goals and moral principles underlying educational services for immigrants. While apparently innocuous, such formulations of the issue stipulate a framework with clear roles: host countries are posited as providers and immigrants as recipients of services. Host countries are, thus, placed in a hierarchical position of ‘granting’ belonging, ‘granting’ services, ‘granting’ education, as benefactors, whether for the purposes of duty, utility, or justice. In this paper, I challenge this unidirectional order of beneficence. I propose that the inclusion of migrants in public institutions should more properly be viewed (also) as providing a necessary good/service for the host communities. The encounter with the alien, the foreign, the migrant, in oneself and in one's world, forces individuals and communities to reflect on what and who they are as well as what and who they want to be – their identity and their future development. I argue that migrant populations with diverse linguistic traditions and customs are uniquely situated to bring to consciousness and help denaturalize the given traditions and culture of their host communities and thus make possible a more self-aware, informed, and freer path of development for their host countries.  相似文献   
93.
The origins of the ability to produce action at will at the hundreds of millisecond to second range remain poorly understood. A central issue is whether such timing is governed by one mechanism or by several different mechanisms, possibly invoked by different effectors used to perform the timing task. If two effectors invoke similar timing mechanisms, then they should both produce similar variability increase with interval duration (interonset interval) and thus adhere to Weber's law (increasing linearly with the duration of the interval to be timed). Additionally, if both effectors invoke the same timing mechanism, the variability of the effectors should be highly correlated across participants. To test these possibilities, we assessed the behavioural characteristics across fingers and eyes as effectors and compared the timing variability between and within them as a function of the interval to be produced (interresponse interval). Sixty participants produced isochronous intervals from 524 to 1431?ms with their fingers and their eyes. High correlations within each effector indicated consistent performance within participants. Consistent with a single mechanism, temporal variability in both fingers and eyes followed Weber's law, and significant correlations between eye and finger variability were found for several intervals. These results can support neither the single clock nor the multiple clock hypotheses but instead suggest a partially overlapping distributed timing system.  相似文献   
94.
Carrier testing is offered on the basis of Ashkenazi Jewish background in both the prenatal and preconception settings, with the goal of decreasing the prevalence of affected individuals and allowing informed decision-making during childbearing. The purpose of this study was to (1) document the demographic characteristics of individuals who attended a free education and screening program, (2) learn how the education program changed attendees' knowledge and attitudes by learning more about these disorders, and (3) determine how participants perceived their carrier status risk. One hundred seventy-four individuals completed questionnaires at the beginning and end of an educational program about the Ashkenazi Jewish genetic disorders. There was a statistically significant difference in the participant's level of knowledge from the pre- to post education (p < .001). Females reported a significantly higher level of concern about the disorders (p = .004) and their carrier status (p = .006) before the education, as well as about their carrier status post education (p = .05). Finally, having one or more parent affiliated with Orthodox Judaism was related to higher knowledge before the education program (p = .05). In conclusion, this study demonstrated that an educational carrier screening program increased knowledge about the disorders and also produced mild anxiety regarding personal and reproductive risks.  相似文献   
95.
Newborn screening (NBS) protocols for cystic fibrosis (CF) are the first regional population-based programs to incorporate DNA analysis into their procedures. Research about these programs can inform policy and practice regarding how best to counsel families with abnormal NBS results. The grounded theory method guided interviews with 33 families whose infants had abnormal CF NBS results. A dimensional analysis of these interviews provided a theoretical framework describing parents’ preferences regarding counseling during their infant's sweat test appointment. This framework describes the contexts and characteristics of the two main dimensions of parents’ preferences: factual information and emotional support. Factual information included learning about the probability of a CF diagnosis, CF disease facts, sweat test procedure, and CF genetics. Social support consisted of offering parents a choice about the timing and amount of CF information, showing empathy for their distress, instilling hope, personalizing counseling, and providing hospitality. This framework also explains the consequences of counseling that matched versus mismatched parental preferences in these domains. Counseling that matched parents preferences reduced parents’ distress while mismatched counseling tended to increase parents’ worry about their infant.  相似文献   
96.
Estrous behavior in rodents is triggered by the binding of progesterone (P) to its intracellular receptor (PR). Non-steroidal agents (i.e., gonadotropin-releasing hormone, noradrenaline, dopamine and others), acting at the membrane, can facilitate estrous behavior in estrogen-primed rats. This action is mediated through the generation of second messengers (cyclic AMP, cyclic GMP, calcium) which, in turn, phosphorylate through diverse kinase systems (protein kinases A, G or C) either the PR or associated effector proteins linking the PR to the trans-activation machinery. P or its metabolites also activate cyclic AMP-signaling pathways by acting directly on the membrane or by modulating neurotransmitter release. Molecular processes resulting from second messenger signaling pathways and those from the progesterone-RP interaction synergize to elicit a full behavioral response.  相似文献   
97.
Genetic discrimination is becoming an increasingly important problem in the United States. Information acquired from genetic tests has been used by insurance companies to reject applications for insurance policies and to refuse payment for the treatment of illnesses. Numerous states and the United States Congress have passed or are considering passage of laws that would forbid such use of genetic information by health insurance companies. Here we argue that much of this legislation is severely flawed because of the difficulty in distinguishing genetic from nongenetic tests. In addition, barring the use by insurance companies of a genetic test but not a nongenetic test (conceivably for the same multifactorial disease) raises issues of fairness in health insurance. These arguments suggest that ultimately the problems arising from genetic discrimination cannot be solved by narrowly focused legislation but only by a modification of the entire health care system.  相似文献   
98.
Genetic counseling for Gaucher disease is complicated by the vast degree of clinical heterogeneity encountered in the disorder. Recent advances in our understanding of the molecular genetics of Gaucher disease are particularly relevant to genetic counseling. Although the identification of mutations in the glucocerebrosidase gene has enabled genotypic screening of Gaucher patients, the ability to reliably predict patient outcome on the basis of DNA studies is often limited. An appreciation of both the spectrum of clinical manifestations in Gaucher patients and the limitations of the available genotypic information is necessary when counseling patients, families and at-risk individuals.  相似文献   
99.
The utility of teacher judgment (rankings, ratings) and peer judgment (sociometric ratings) were studied as screening variables for preschool social withdrawal/responsiveness. Observational measures of preschoolers' interaction were used as the validation criterion based upon theoretical, empirical, and practical considerations related to development of a multipurpose behavioral assessment system. Results indicated that teacher rankings of students' verbal interaction frequencies (1) were most highly correlated to interaction rate in two preschool settings, (2) had test-retest reliability consistently above Rho = .80, and (3) were useful in that 77% of teachers using this procedure could identify their least socially responsive student within five rankings. The peer nomination sociometric rating was the least reliable measure at retest (Rho = .35) and showed consistently the lowest correlation with observational indices of interaction partner preferences, e.g., reciprocal rate (Rho = .29 to .39). The tendency for relationships among screening measures and the criterion to increase at retest suggested a training effect on screening accuracy. The use of teacher rankings in combination with observational measures to confirm selection accuracy and for monitoring treatment progress is discussed as a cost-effective behavioral assessment procedure for preschool social withdrawal/responsiveness.  相似文献   
100.
Contributions to factor analysis of dichotomous variables   总被引:5,自引:0,他引:5  
A new method is proposed for the factor analysis of dichotomous variables. Similar to the method of Christoffersson this uses information from the first and second order proportions to fit a multiple factor model. Through a transformation into a new set of sample characteristics, the estimation is considerably simplified. A generalized least-squares estimator is proposed, which asymptotically is as efficient as the corresponding estimator of Christoffersson, but which demands less computing time.This research was supported by the Bank of Sweden Tercentenary Foundation under project Structural Equation Models in the Social Sciences, project director Karl G. Jöreskog.  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