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   47007篇
  免费   1151篇
  国内免费   11篇
  48169篇
  2020年   314篇
  2019年   429篇
  2018年   3928篇
  2017年   3280篇
  2016年   2779篇
  2015年   677篇
  2014年   591篇
  2013年   2392篇
  2012年   1435篇
  2011年   3278篇
  2010年   3015篇
  2009年   1976篇
  2008年   2389篇
  2007年   2884篇
  2006年   710篇
  2005年   832篇
  2004年   747篇
  2003年   689篇
  2002年   654篇
  2001年   859篇
  2000年   823篇
  1999年   610篇
  1998年   305篇
  1997年   267篇
  1996年   290篇
  1995年   246篇
  1992年   491篇
  1991年   488篇
  1990年   485篇
  1989年   430篇
  1988年   457篇
  1987年   411篇
  1986年   416篇
  1985年   434篇
  1984年   351篇
  1983年   298篇
  1982年   250篇
  1979年   387篇
  1978年   294篇
  1977年   253篇
  1975年   315篇
  1974年   380篇
  1973年   395篇
  1972年   308篇
  1971年   302篇
  1970年   301篇
  1969年   265篇
  1968年   354篇
  1967年   315篇
  1966年   288篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
112.
Difficulties with the Microsoft BASIC function for generating random numbers (RND) are cited and new problems reported. Fixes are suggested that allow use of some of the speed of the original function and that produce greatly improved pseudorandom numbers. A published generator is combined with the RND function as a compromise solution.  相似文献   
113.
We outline a BASIC program and subsidiary machine language timing routines that enable the Apple II series of computers to be employed as control devices for the tachistoscopic presentation of 35-mm slides and the collection of response latencies. The program is functional for experiments that require pictorial stimuli to be presented in up to three separate fields, with precise display times, precise interstimulus and intertriai intervals, and the collection of manual or vocal reaction times with millisecond accuracy. The major advantages of this system are that initial setup costs are substantially lower than those for other similar systems (e.g., Loftus, Gillispie. Tigre, & Nelson, 1984) and that user customization of the program may be accomplished by anyone possessing rudimentary knowledge of the BASIC programming language.  相似文献   
114.
115.
Maternal handling and motor development: an intracultural study   总被引:1,自引:0,他引:1  
Citing a distinction between informal and formal routines used by mothers in handling their infants, we examined formal handling routines, in which the caregiver acts in a pedagogical manner; these routines are widespread in many non-Western countries. We hypothesised that formal handling serves to facilitate gross motor development during early infancy. To examine this hypothesis, the effects of a Jamaican formal handling routine on a broad range of developmental outcomes was examined. Results showed that the effects were specific to early gross motor development and in particular to postural control along the vertical axis of the body. Information is also provided on other aspects of Jamaican child care. It seems that the handling routine forms part of a folk (developmental) medicine system and may serve not only to promote child health but also as a sort of developmental neurological examination.  相似文献   
116.
Differences in school behavior and achievement between students from intact, reconstituted, and single-parent families were analyzed. Students from intact two-parent families had fewer absences and tardies, higher grade point averages, and fewer negative and more positive teacher behavioral ratings than did those from reconstituted and single-parent families.  相似文献   
117.
118.
Neutrality is a central concept within the theory of psychoanalytic technique. We spell out the major controversies in which the concept has become embroiled, and provide a definition that we believe coincides with actual psychoanalytic practice. We discuss its merits and weaknesses, noting also the negative consequences of relying on older definitions. We relate neutrality to the interpretive process, indicating ways interpretation protects neutrality and is made more effective by it. We discuss the complex and controversial relation between neutrality and the analyst's therapeutic intent.  相似文献   
119.
Forty-one nonpsychiatric subjects, 38 probands with schizophrenia, and 99 of their relatives were studied. Oculomotor functioning was bimodally distributed for probands and relatives. Oculomotor dysfunction was not present in all families with a schizophrenic proband. In those families in which it was present, there were significant phenotypic correlations between oculomotor functioning and schizophrenia-related characteristics. The patterns of familial resemblance in the families in whom oculomotor dysfunction was present were consistent with nonadditive genetic variance contributing both to oculomotor dysfunction and to the relationship between oculomotor dysfunction and clinical symptoms. These results suggest that schizophrenia may be etiologically heterogeneous and that oculomotor dysfunction may help to identify nonadditive genetic variance for this disorder.  相似文献   
120.
While the long-term effects of combat trauma on veterans have been studied extensively, its impact on veterans' wives has yet to be investigated. This study examined the implications of combat-induced psychopathology--wartime combat stress reaction (CSR) and current posttraumatic stress disorder (PTSD)--in a sample of 205 wives of Israeli combat veterans of the 1982 Lebanon war. Results show that both CSR and PTSD were associated with increased psychiatric symptoms in the wives. In addition, current PTSD was particularly found to contribute to impaired social relations among veterans' wives in a broad range of contexts, from inner feelings of loneliness, through impaired marital and family relations, and extending to the wider social network. Implications of these findings for treatment and further research are discussed.  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