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991.
Is human immunodeficiency virus still a terminal condition? Recent advances in treatment have significantly reduced both mortality and morbidity associated with HIV, but these treatments have not been successful in eradicating the virus itself. As such, HIV has evolved into a chronic condition that is complicated by neurocognitive factors. Cognitive difficulties associated with HIV are characterized by a subcortical pattern with primary deficits in information processing speed and psychomotor speed. These deficits interfere with the ability of patients to complete important instrumental activities of daily living even in the absence of dementia. Treatment of HIV improves neurocognitive functioning, but the regimens are complex and patient adherence is critical. Cognitive factors can negatively impact treatment adherence, which in turn results in poorer immunological, cognitive, and psychiatric outcome. This cycle emphasizes the important interrelationships between symptom expression and treatment outcome in patients with HIV. The nature of these relationships will change with further developments in treatment regimens such as once-daily dosing. Less complex treatment approaches should improve health outcome as well as provide additional opportunities to further understand the impact of HIV on brain function. 相似文献
992.
Green RM 《The American journal of bioethics : AJOB》2002,2(1):20-30
In this chapter, I review some of the background thinking concerning matters of moral status that I had developed in previous years and that I would now bring to the work of the Human Embryo Research Panel. Two ideas were at the forefront of my thinking. First, that biology usually offers not decisive "events" but only continuous processes of development. Second, in making status determinations we do not so much "identify" a point on a developmental continuum where moral respect should be accorded as "choose" that point. These choices are "balancing decisions" in which the community of moral agents weighs its interests in protecting an entity against the burdens of doing so. After illustrating these two contentions, I consider some of the reasons why thinkers on the "right" and "left" of our bioethics debates have resisted or missed this basic insight. 相似文献
993.
Standard chi-square-based fit indices for factor analysis and related models have a little known property: They are more sensitive to misfit when unique variances are small than when they are large. Consequently, very small correlation residuals indicating excellent fit can be accompanied by indications of bad fit by the fit indices when unique variances are small. An empirical example of this incompatibility between residuals and fit indices is provided. For illustrative purposes, an artificial example is provided that yields exactly the same correlation residuals as the empirical example but has larger unique variances. For this example, the fit indices indicate excellent fit. A theoretical explanation for this phenomenon is provided using relationships between unique variances and eigenvalues of the fitted correlation matrix. 相似文献
994.
de Kloet ER Grootendorst J Karssen AM Oitzl MS 《Neurobiology of learning and memory》2002,78(3):570-577
A fundamental question in the neurobiology of cognition is how stress and glucocorticoids modify learning and memory processes. Why some individuals develop cognitive deficits after stress, while other individuals improve in cognitive performance under similar adverse conditions is still unresolved. To address these questions we focus on those issues. First, corticosterone, which appears to be the preferred glucocorticoid for the rodent and human brain, acts via brain mineralocorticoid (MR) and glucocorticoid receptors (GR) on the expression of networks of corticosteroid-responsive genes. Different effects are achieved by MR and GR activation. Second, the experimental context that determines the timing and the consequences of corticosterone action during the various stages of information processing is reviewed. Third, the genetic context and the environmental context are investigated. Using apolipoprotein E knockout (apoE0/0) mice we show that apoE (apoE4 is a genetic risk factor for Alzheimer's disease) is a candidate gene with an important function in shaping the cognitive outcome (genotype x environment interaction). 相似文献
995.
James K. Luiselli Denise Dion Erin Hammil Andrea Potoczny-Gray Ronald C. Savage Donald L. Sherak 《Journal of child and family studies》2000,9(4):481-489
There is a high prevalence of psychiatric disorders in children and adolescents who have acquired brain injury (ABI). We examined the records of 82 students with ABI who were admitted to a community-based school for education and neurorehabilitation over a three-year period to determine how many experienced one or more psychiatric hospitalizations before admission, and whether hospitalization status was related to positive school and community adjustment. Results were that 30.4% of the students had a documented history of one or more psychiatric hospitalizations. Of this group, 60.0% were able to be maintained in the community-based school program and 40.0% were discharged to other settings. When discharged, 70.0% of students entered more restrictive treatment programs (e.g., psychiatric hospital, secure residential facility, residential school). The number of psychiatric hospitalizations did not predict discharge from the community-based school and was unrelated to the type of discharge setting. Clinical and research issues concerning psychiatric disorders in children and adolescents with ABI in relation to post-acute adjustment are discussed. 相似文献
996.
997.
Ronald Glasberg 《Zygon》2003,38(2):277-294
This article is a spiritual interpretation of Leonhard Euler's famous equation linking the most important entities in mathematics: e (the base of natural logarithms), π (the ratio of the diameter to the circumference of a circle), i (√‐1),1 , and . The equation itself (eπi+1 = 0> ) can be understood in terms of a traditional mathematical proof, but that does not give one a sense of what it might mean. While one might intuit, given the significance of the elements of the equation, that there is a deeper meaning, one is not in a position to get at that meaning within the discipline of mathematics itself. It is only by going outside of mathematics and adopting the perspective of theology that any kind of understanding of the equation might be gained, the significant implication here being that the whole mathematical field might be a vast treasure house of insights into the mind of God. In this regard, the article is a response to the monograph by George Lakoff and Rafael Núñez, Where Mathematics Comes From: How the Embodied Mind Brings Mathematics into Being (2000), which attempts to approach mathematics in general and the Euler equation in particular in terms of some basic principles of cognitive psychology. It is my position that while there may be an external basis for understanding mathematics, the results are somewhat disappointing and fail to reveal the full measure of meaning buried within that equation. 相似文献
998.
School bonding refers to the connections that youth have with their schools and various aspects of their academic lives. School bonding may be an important concept in prevention because it has been linked to various developmental and adjustment outcomes. This paper reviews conceptualizations, measurements, and theories of school bonding. Also considered are empirical studies that have linked school bonding to a variety of outcomes (substance use, delinquency, antisocial behavior, self-esteem). The review includes examination of how school bonding serves as a mediator in these relations and, in turn, is moderated by other variables. Despite inconsistencies in conceptualization and measurement, it is concluded that school bonding is an important construct and an appropriate target for intervention. Recommendations are offered regarding future research on school bonding, especially with respect to positive developmental outcomes and examination of variables that might moderate school bonding. 相似文献
999.
The purpose of the study was to assess medical journals’ conflicts of interest in the publication of book reviews. We examined
book reviews published in 1999, 2000, and 2001 (N=1,876) in five leading medical journals: Annals of Internal Medicine, British Medical Journal (BMJ), Journal of the American Medical Association (JAMA), Lancet, and New England Journal of Medicine. The main outcome measure was journal publication of reviews of books that had been published by the journal’s own publisher,
that had been edited or authored by a lead editor of the journal, or that posed another conflict of interest. We also surveyed
the editors-in-chief of the five journals about their policies on these conflicts of interests. During the study period, four
of the five journals published 30 book reviews presenting a conflict of interest: nineteen by the BMJ, five by the Annals, four by JAMA, and two by the Lancet. These reviews represent 5.8%, 2.7%, 0.7%, and 0.7%, respectively, of all book reviews published by the journals. These four
journals, respectively, published reviews of 11.9%, 25.0%, 0.9%, and 1.0% of all medical books published by the journals’
publishers. Only one of the 30 book reviews included a disclosure statement addressing the conflict of interest. None of the
journals had a written policy pertaining to the conflicts of interest assessed in this study, although four reported having
unwritten policies. We recommend that scientific journals and associations representing journal editors develop policies on
conflicts of interest pertaining to book reviews.
Disclosure: R.M. Davis was North American editor of the BMJ from 1998 to 2001, and is a member of the Board of Trustees of the American Medical Association, which publishes JAMA. The opinions expressed in this paper are those of the authors and do not reflect the official policy of any organization
with which the authors have been affiliated. 相似文献
1000.
Children Exposed to Community Violence or War/Terrorism: Current Status and Research Directions—Introduction 总被引:1,自引:1,他引:0
This issue of Clinical Child and Family Psychology Review, Children Exposed to Community Violence or War/Terrorism: Current Status and Research Directions, addresses the current status of our knowledge as well as critical research needs in the area of children exposed to violence outside the family. Although much has been learned in recent years about children exposed to violence, significant research gaps remain, the identification of which may help to build a more complete and rigorous science base in this area. This journal issue represents the distillation of a 3-day workshop on children exposed to violence, held in July of 2002, that identified what is known about children exposed to violence and what this information tells us about future research directions. Although many federal agencies have supported some research in this area, there is a need for more targeted attention on the topic, particularly with regard to measurement, sampling, and interventions/services. The papers in this issue were selected with these themes in mind. Although no single issue could cover the entire field, we intend to offer a representative sample of where we are and where we need to go with the hope of stimulating additional thought, collaboration, and research in this important area. 相似文献