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   67308篇
  免费   1373篇
  国内免费   7篇
  68688篇
  2020年   641篇
  2019年   804篇
  2018年   1067篇
  2017年   1135篇
  2016年   1167篇
  2015年   884篇
  2014年   1001篇
  2013年   4756篇
  2012年   1850篇
  2011年   1932篇
  2010年   1257篇
  2009年   1197篇
  2008年   1736篇
  2007年   1653篇
  2006年   1481篇
  2005年   1345篇
  2004年   1255篇
  2003年   1245篇
  2002年   1203篇
  2001年   2196篇
  2000年   2130篇
  1999年   1567篇
  1998年   719篇
  1997年   607篇
  1992年   1430篇
  1991年   1353篇
  1990年   1347篇
  1989年   1192篇
  1988年   1179篇
  1987年   1147篇
  1986年   1138篇
  1985年   1261篇
  1984年   1007篇
  1983年   864篇
  1982年   630篇
  1981年   622篇
  1979年   1062篇
  1978年   721篇
  1977年   701篇
  1976年   658篇
  1975年   934篇
  1974年   1006篇
  1973年   1091篇
  1972年   925篇
  1971年   833篇
  1970年   825篇
  1969年   830篇
  1968年   1065篇
  1967年   929篇
  1966年   905篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
42.
Despite widespread popular belief in the activation of recurrent lesions in genital herpes simplex virus (HSV) by psychosocial stress, little empirical evidence supports that contention. This study retrospectively examined the role of stress in activation of HSV lesions as mediated by social support. Participants were 59 volunteers who had self-reported culture-positive genital HSV for at least 10 months. Measures of stress proneness (State-Trait Anxiety Inventory; STAI-Trait), recent stressful events (Schedule of Recent Events; SRE), and subjective appraisal of stress (global self-rating) were administered along with measures of general social support and herpes-specific social support. When retrospective reports of HSV symptoms were examined using a multiple-regression approach, duration of disease and amount of herpes-specific social support were found to be significant moderators of the relation between stress and number of HSV recurrences in the preceding 12 months. When duration of disease was short (less than 4 years), stress (SRE) and number of recurrences were positively associated; when disease duration was longer, there was no relationship. Similarly, at low levels of herpes-specific social support, a positive relation between stress (SRE) and number of recurrences was found. However, at higher levels of herpes-specific social support, no association was found. No relation was found between stress proneness (STAI-Trait) and HSV symptoms. However, subjective appraisal (global rating) of stress in the preceding 12 months was positively and significantly correlated with reported number of recurrences. Results are discussed in terms of their clinical implications.  相似文献   
43.
Analogical transfer, problem similarity, and expertise   总被引:6,自引:0,他引:6  
When we encounter a new problem, we are often reminded of similar problems solved earlier and may use the solution procedure from an old problem to solve a new one. Such analogical transfer, however, has been difficult to demonstrate empirically, even within a single experimental session. This article proposes a framework for conceptualizing analogical problem solving that can account for the conflicting findings in the literature. In addition, the framework leads to two predictions concerning the transfer behavior of experts and novices. These predictions concern both positive and negative transfer and are based on the different types of features included in the problem representations of experts and novices. First, when two problems share structural features but not surface features, spontaneous positive transfer should be more likely in experts than in novices. Second, when two problems share surface but not structural features, spontaneous negative transfer should be stronger for novices than for experts. These predictions were supported by the results of three experiments involving college students solving a complex arithmetic word problem.  相似文献   
44.
Group work as an integral part of counsellor training appears to have been under-utilised. Certainly it is the case that empirical evaluations of such group work appear rarely in guidance and counselling journals. An attempt is made to remedy these deficiencies by reviewing studies relevant to counsellor training and to report on 17 years of research and experience with group work within a counsellor training programme at a New Zealand university.  相似文献   
45.
The vocationally-indecisive individual presents a major counselling problem. The theory and research behind career indecision is discussed and a counselling approach based on identity formation is outlined. Four identity statuses — Identity Achievements, Foreclosures, Identity Diffusions, and Moratoriums — are described and counselling approaches for each are explored.  相似文献   
46.
Rats were allowed to forage in a simulated natural environment made up of eight food sources (patches) each containing a fixed number of pellets. Two of the eight contained an extra supply of peanuts. The peanut patches were signaled by an olfactory/visual cue located at the bottom of the ladder leading to the patch. In successive phases the number of sessions per day, height of the patches, and availability of peanuts were manipulated. Subjects showed evidence of discrimination learning under these conditions, although the degree of discriminatory behavior varied as a function of environmental manipulations. Assessment of behavior within foraging sessions showed that subjects systematically changed their patterns of utilization of patches across time. Sampling or exploration, as well as food reinforcement, seem implicated in these results.  相似文献   
47.
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109.  相似文献   
48.
49.
On analog movements of visual attention   总被引:2,自引:0,他引:2  
  相似文献   
50.
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