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   12552篇
  免费   517篇
  国内免费   6篇
  2023年   67篇
  2022年   63篇
  2021年   125篇
  2020年   219篇
  2019年   264篇
  2018年   340篇
  2017年   314篇
  2016年   373篇
  2015年   253篇
  2014年   339篇
  2013年   1354篇
  2012年   577篇
  2011年   575篇
  2010年   420篇
  2009年   424篇
  2008年   595篇
  2007年   581篇
  2006年   517篇
  2005年   449篇
  2004年   483篇
  2003年   441篇
  2002年   430篇
  2001年   186篇
  2000年   213篇
  1999年   200篇
  1998年   194篇
  1997年   161篇
  1996年   115篇
  1995年   153篇
  1994年   149篇
  1993年   132篇
  1992年   134篇
  1991年   118篇
  1990年   118篇
  1989年   111篇
  1988年   117篇
  1987年   117篇
  1986年   92篇
  1985年   116篇
  1984年   119篇
  1983年   103篇
  1982年   118篇
  1981年   118篇
  1980年   112篇
  1979年   109篇
  1978年   114篇
  1977年   92篇
  1976年   103篇
  1975年   74篇
  1974年   84篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
91.
Using a backward-masking paradigm with a bias-free and ceiling-free psychophysical task, we tested hypnotized and control subjects for speed of visual information processing. Approximately half of each group received visual imagery suggestions in an attempt to influence attention. Imagery produced no significant differential effect. Although an absence of a hypnotizability-performance relationship was in keeping with findings of a previous study, those subjects in the present study who performed under hypnosis were, as a group, significantly superior to the other subjects in speed of information processing.  相似文献   
92.
The FACES instrument, based on Olson's Circumplex Model of family functioning, was administered to 96 adolescent drug-abuse clients and their parents. The majority of these families categorized themselves as "disengaged" (rather than "enmeshed") on the cohesion dimension, and as "rigid" (rather than "chaotic") on the adaptability dimension. These findings were unexpected as they were substantially different from published findings on families with other types of problems. Family therapists, utilizing Olson's Clinical Rating Scale for the Circumplex Model, characterized significantly more of these same families as "enmeshed," rather than "disengaged." Possible explanations for the difference between the therapists' perceptions and the families' self-perceptions are discussed.  相似文献   
93.
The evolution of a therapy group for hospitalized Vietnam veterans with post-traumatic stress disorder (PTSD) and related symptomatology is described. The literature on group treatment for this population is briefly reviewed and discussed in relation to an inpatient psychiatry setting. The prevailing conditions at the time of group inception are recalled along with the initial goals of the therapeutic intervention. Problems encountered are also discussed, along with the changes made in response to these identified difficulties. The results of three and one-half years of experience with this group are described in detail.The authors would like to thank Cynthia Sturm, Ph.D. for her helpful editorial assistance.  相似文献   
94.
The acquired immune deficiency syndrome (AIDS) has rapidly become the most serious medical consequence of injecting illicit drugs. Its potential impact on intravenous (IV) drug use is enormous. Human immunodeficiency virus (HIV, also known as HTLV-III and LAV), the virus that causes AIDS, appears, usually, to lead to lifelong infection. At present there is no effective treatment, and the treatments under development may require lifelong antiviral therapy. Since most of the antibody produced in response to HIV infection does not neutralize the virus, and since there is substantial genetic variation in the virus, it will be difficult to develop a vaccine. Even after vaccines are developed, testing their safety and efficacy will be formidable problems. Until either effective treatment or vaccines are developed, control of the epidemic among IV drug users must be attempted through behavior change/prevention efforts. In this paper we will review the epidemiology of AIDS among IV drug users and characteristics of the IV drug-use subculture relevant to prevention efforts. We will then identify different target groups for these prevention efforts, present available evidence about behavior change in these groups, and then briefly discuss how to prevent transmission of HIV to heterosexual partners who are not themselves IV drug users and to the children of IV drug users.  相似文献   
95.
The present study examined the hypothesis that individuals are more influenced by a drug name than by the side effects associated with that drug when making recommendations regarding regulation. Subjects recommended the amount of regulation that should exist for eight drugs ranging from aspirin to LSD. One third of the subjects were asked to make recommendations based only on the drug name. Another third made recommendations based only on the facts associated with the drugs (i.e., side effects, symptoms). A final third made recommendations based on both facts and the drug name. Results indicated that, when given only the facts, subjects' recommendations deviated greatly from the actual regulation of the drugs but that the facts were ignored if subjects knew the name of the drug. These results suggest that critical information may be ignored when decisions are made about drug regulation. The implications for self-regulated drug use are discussed.  相似文献   
96.
Although meditation is increasingly being employed as an adjunct in psychotherapy, there has been practically no comprehensive evaluation of its usefulness in this respect. This paper seeks to address this issue through conceptual models of the meditation experience. It is concluded that meditation practice may be associated with the acquisition of some useful skills (e.g., focused attention), that practice may be physiologically relaxing, that meditation may decrease anxiety, insomnia and drug usage, while enhancing hypnotic induction and self-actualization. There is still no compelling evidence, however, that meditation practice is associated with unique state effects compared with other relaxational procedures. Those who appear to benefit most from meditation appear to be those who present with milder disorders. The clinical value of meditation, therefore, appears to be limited. Furthermore, the long-term objectives of meditation are not in general congruent with those of mainstream psychotherapy, as they go beyond therapeutic gain in the clinical sense.  相似文献   
97.
98.

Two experiments investigated the role of lithium-mediated environmental conditioning on instrumental performance. Experiment 1 demonstrated that a novel taste consumed in one arm of a T maze prior to lithium-induced toxicosis reduced performance in this environment whereas similar aversions conditioned in the home cage failed to alter maze performance. Experiment 2 showed that maze performance in a straight alleyway was decremented during extinction only in a group that actually traversed the alley prior to drinking saccharin and receiving lithium injections. This demonstrated that the instrumental decrement observed in Experiment 1 was due not only to the presence of an unpalatable flavor in the goalbox during the test.

  相似文献   
99.
Regional cerebral glucose metabolism in aphemia: A case report   总被引:1,自引:0,他引:1  
Local cerebral metabolism was determined in a patient suffering aphemia following cerebral infarction using the 18FDG-PET technique. The syndrome was characterized by profound ictal nonfluency with sparing of other language functions. Speech subsequently improved so that content and grammar were appropriate but mild dysprosody persisted. Conventional CT showed no lesion of the left hemisphere while PET revealed a discrete focus of hypometabolism on the left which partially resolved on serial studies. The metabolic lesion could be localized to the region of the inferior precentral gyrus and the adjacent subcortical space.  相似文献   
100.
Two experiments investigated the modulation of event-related potentials (ERPs) by the repetition of orthographically legal and illegal nonwords. In Experiment 1, subjects silently counted occasional words against a background of nonwords, a proportion of which were repetitions of an immediately preceding legal or illegal item. ERPs to repeated legal items showed a sustained, topographically diffuse, positive-going shift. In contrast, repeated illegal nonwords gave rise to ERPs showing a smaller and temporally more restricted positive-going modulation. In an attempt to equalize depth of processing across legal and illegal nonwords, subjects in Experiment 2 were required to count items containing a nonalphabetic character against the same background of nonword items. ERPs to repeated legal items showed a modulation similar to, although smaller than, that found in Experiment I, but no effects of repetition were observed in the ERPs to the illegal nonwords. It was concluded that the effects of repeating nonwords, at least as manifested in concurrently recorded ERPs, differ as a consequence of whether items can access lexical memory, and that this is inconsistent with the attribution of such effects solely to the operation of episodic memory processes.  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