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   4495篇
  免费   117篇
  国内免费   41篇
  4653篇
  2024年   48篇
  2023年   75篇
  2022年   56篇
  2021年   93篇
  2020年   134篇
  2019年   116篇
  2018年   206篇
  2017年   217篇
  2016年   188篇
  2015年   140篇
  2014年   176篇
  2013年   622篇
  2012年   346篇
  2011年   351篇
  2010年   215篇
  2009年   112篇
  2008年   296篇
  2007年   228篇
  2006年   228篇
  2005年   121篇
  2004年   105篇
  2003年   79篇
  2002年   76篇
  2001年   34篇
  2000年   59篇
  1999年   34篇
  1998年   32篇
  1997年   20篇
  1996年   20篇
  1995年   9篇
  1994年   26篇
  1993年   15篇
  1992年   12篇
  1991年   14篇
  1990年   18篇
  1989年   16篇
  1988年   10篇
  1987年   12篇
  1986年   4篇
  1985年   7篇
  1984年   8篇
  1983年   4篇
  1981年   5篇
  1979年   6篇
  1978年   5篇
  1975年   5篇
  1974年   8篇
  1970年   4篇
  1968年   5篇
  1966年   4篇
排序方式: 共有4653条查询结果,搜索用时 0 毫秒
911.
In two experiments, the perceptual similarity between a strong tonal melody and various transpositions was investigated using a paradigm in which listeners compared the perceptual similarity of a melody and its transposition with that of the same melody and another transposition. The paradigm has the advantage that it provides a direct judgment regarding the similarity of transposed melodies. The experimental results indicate that the perceptual similarity of a strong tonal melody and its transposition is mainly determined by two factors: (1) the distance on the height dimension between the original melody and its transposition (pitch distance), and (2) the distance between keys as inferred from the circle of fifths (key distance). The major part of the variance is explained by the factor pitch distance, whereas key distance explains only a small part.  相似文献   
912.
913.
914.
915.
3 groups of patients, who suffered on SSPE (without treatment, with isoprinosine therapy, combined treatment with propionibacterium granulosum and isoprinosine) are compared. The results show a favourable effect of the combined treatment in a part of the patients. They are discussed in detail.  相似文献   
916.
Two experimental tasks, a speech segmentation and a short-term memory task, were presented to children who began to learn to read following either the “phonic” or the “wholeword” method. The segmentation task required the child to reverse two segments (either two phones or two syllables) in an utterance. The phonic group performed significantly better than the whole-word group in the “phonic reversal” task, but no difference appeared in the “syllable reversal” task. This indicated (1) that most children by the age of 6 years are ready to discover that speech consists of a sequence of phones and (2) that the moment at which they do it is influenced by the way they are taught to read. In the memory task, the children recalled series of visually presented items whose names either rhymed or did not. The difference in performance for the rhyming and nonrhyming series was significant in both groups. It was no greater for the phonic than for the whole-word group and was uncorrelated with the “phonic reversal” task. These results are discussed in connection with the distinction between ways of lexical access and ways of representing verbal information in short-term memory.  相似文献   
917.
Philosophia - The social nature of human beings and individualistic characterizing destiny of individuals is contradictory and call for philosophical interrogation. Segun Ogungbemi has...  相似文献   
918.
Science and Engineering Ethics - Synthetic biology opens up the possibility of producing new entities not found in nature, whose classification as organisms or machines has been debated. In this...  相似文献   
919.
Early partial maternal deprivation causes long-lasting neurochemical, behavioral and brain structural effects. In rats, it causes a deficit in memory consolidation visible in adult life. Some of these deficits can be reversed by donepezil and galantamine, which suggests that they may result from an impairment of brain cholinergic transmission. One such deficit, representative of all others, is an impairment of memory consolidation, clearly observable in a one-trial inhibitory avoidance task. Recent data suggest a role of brain histaminergic systems in the regulation of behavior, particularly inhibitory avoidance learning. Here we investigate whether histamine itself, its analog SKF-91844, or various receptor-selective histamine agonists and antagonists given into the CA1 region of the hippocampus immediately post-training can affect retention of one-trial inhibitory avoidance in rats submitted to early postnatal maternal deprivation. We found that histamine, SKF-91844 and the H2 receptor agonist, dimaprit enhance consolidation on their own and reverse the consolidation deficit induced by maternal deprivation. The enhancing effect of histamine was blocked by the H2 receptor antagonist, ranitidine, but not by the H1 receptor antagonist pyrilamine or by the H3 antagonist thioperamide given into CA1 at doses known to have other behavioral actions, without altering locomotor and exploratory activity or the anxiety state of the animals. The present results suggest that the memory deficit induced by early postnatal maternal deprivation in rats may in part be due to an impairment of histamine mediated mechanisms in the CA1 region of the rat hippocampus.  相似文献   
920.
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