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   56144篇
  免费   2193篇
  国内免费   24篇
  2020年   587篇
  2019年   751篇
  2018年   1035篇
  2017年   1129篇
  2016年   1153篇
  2015年   831篇
  2014年   995篇
  2013年   4453篇
  2012年   1776篇
  2011年   1797篇
  2010年   1149篇
  2009年   1093篇
  2008年   1548篇
  2007年   1595篇
  2006年   1402篇
  2005年   1275篇
  2004年   1199篇
  2003年   1155篇
  2002年   1190篇
  2001年   1746篇
  2000年   1681篇
  1999年   1311篇
  1998年   572篇
  1997年   545篇
  1996年   539篇
  1995年   520篇
  1992年   1105篇
  1991年   1014篇
  1990年   1045篇
  1989年   940篇
  1988年   995篇
  1987年   916篇
  1986年   931篇
  1985年   868篇
  1984年   759篇
  1983年   710篇
  1982年   526篇
  1979年   856篇
  1978年   625篇
  1977年   532篇
  1975年   694篇
  1974年   807篇
  1973年   841篇
  1972年   657篇
  1971年   633篇
  1970年   590篇
  1969年   620篇
  1968年   770篇
  1967年   695篇
  1966年   612篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
45.
46.
47.
48.
49.
OBJECTIVE: This report reviews the evidence that informs the role of health and mental health care providers in addressing youth smoking cessation. DESIGN: Qualitative literature review. RESULTS: Physicians do not consistently screen adolescents for tobacco use and fail to provide recommended cessation advice. Challenges to addressing smoking cessation include the need for procedures to ensure confidentiality and the existence of competing demands to provide other services. Few published studies have specifically addressed the effectiveness of clinical interventions. Interventions that require return visits or follow-up phone contacts are technically difficult to implement in this population. Successful interventions may require resources not available in nonresearch settings. Most studies have used brief clinical intervention as a control condition, making it impossible to evaluate its effectiveness. CONCLUSION: There is little evidence that supports current clinical smoking cessation guidelines for adolescents. More research is needed to develop inexpensive, efficient clinical interventions that can provide youths access to smoking cessation help. Future challenges include reorganizing clinical systems to offer greater counseling by support staff or in electronic formats and to provide effective booster messages and follow-up care in a population that is difficult to track.  相似文献   
50.
Previous work on children's intuitive knowledge about the natural world has documented their difficulty in acquiring an overarching concept of biological life that includes plants as well as humans and non‐human animals. It has also suggested that the acquisition of fundamental biological concepts like alive and die may be influenced by the language used to describe them, as evidenced by differences between English‐ and Indonesian‐speaking children's performance in tasks involving these concepts. Here, we examine one particularly important source of linguistic information available to children during this acquisition process: everyday conversations with their parents. We take a cross‐linguistic approach in analysing the evidence available to English‐ and Indonesian‐speaking children as they acquire meanings for words corresponding to the concepts alive and die . Our analysis illustrates that young children acquiring English and Indonesian are faced with distinct problems, but that parental input in both languages does little to support the acquisition of broad, inclusive biological concepts.  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