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   38265篇
  免费   1494篇
  国内免费   15篇
  2020年   445篇
  2019年   560篇
  2018年   748篇
  2017年   813篇
  2016年   823篇
  2015年   573篇
  2014年   706篇
  2013年   3013篇
  2012年   1276篇
  2011年   1279篇
  2010年   829篇
  2009年   787篇
  2008年   1151篇
  2007年   1174篇
  2006年   1039篇
  2005年   929篇
  2004年   859篇
  2003年   816篇
  2002年   825篇
  2001年   1176篇
  2000年   1129篇
  1999年   891篇
  1998年   394篇
  1997年   380篇
  1996年   355篇
  1995年   364篇
  1992年   740篇
  1991年   649篇
  1990年   707篇
  1989年   612篇
  1988年   651篇
  1987年   602篇
  1986年   611篇
  1985年   554篇
  1984年   513篇
  1983年   486篇
  1982年   357篇
  1979年   580篇
  1978年   400篇
  1977年   350篇
  1975年   456篇
  1974年   499篇
  1973年   543篇
  1972年   401篇
  1971年   395篇
  1970年   360篇
  1969年   408篇
  1968年   476篇
  1967年   430篇
  1966年   357篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
32.
33.
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   
34.
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   
35.
This paper examines college students' attributions about suicide as a function of gender and context (athletic vs. relationship failure). Results indicated that male athletes who suicided were considered more emotionally well-adjusted compared to males who suicided because of a relationship failure and all females. Male and female athletes who suicided were seen as more competent and less distressed compared to those who suffered a failed relationship. Females were also seen as more distressed compared to males. These results are discussed in terms of a positive bias toward athletes in our society as well as gender stereotypes. Implications of these findings as well as methodological limitations are discussed.  相似文献   
36.
The current study was designed to gain a better understanding of the nature of the relationship between substance use and sexual risk taking within a community sample of women (N = 1,004). Using confirmatory factor analysis, the authors examined the factor structure of sexual risk behaviors and substance use to determine whether they are best conceptualized as domains underlying a single, higher order, risk-taking propensity. A 2 higher order factor model (sexual risk behavior and substance use) provided the best fit to the data, suggesting that these 2 general risk domains are correlated but independent factors. Sensation seeking had large general direct effects on the 2 risk domains and large indirect effects on the 4 first-order factors and the individual indicators. Negative affect had smaller, yet still significant, effects. Impulsivity and anxiety were unrelated to sexual health risk domains.  相似文献   
37.
38.
The purpose of this study was to examine speech convergence and speech evaluation in fact-finding interviews conducted in the field. Forty interviewers (ERs), undergraduates enrolled in a class on interviewing processes, conducted 20–30 minute interviews with selected interviewees (EEs), business persons and professionals in fields of interest to the ERs. Speech behaviors examined included response latency, speech rate, and turn duration; these were coded per one minute intervals of each interaction. Time series regression procedures indicated that both ERs and EEs converged speech rate and response latency toward their interlocutors' performances of these behaviors. Although turn duration convergence did not characterize the entire data set, male-male dyads did converge significantly and male (ER)-female (EE) dyads significantly diverged turn duration. Regarding speech evaluation, there was some evidence that greater response latency similarity, greater speech rate and response latency convergence, and faster ER speech and slower EE speech were positively related to the competence and social attractiveness judgments of participants. Limitations and implications are discussed.  相似文献   
39.
40.
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