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   6303篇
  免费   487篇
  国内免费   14篇
耳鼻咽喉   29篇
儿科学   261篇
妇产科学   170篇
基础医学   888篇
口腔科学   146篇
临床医学   677篇
内科学   1310篇
皮肤病学   91篇
神经病学   636篇
特种医学   113篇
外科学   644篇
综合类   42篇
一般理论   2篇
预防医学   734篇
眼科学   99篇
药学   411篇
中国医学   5篇
肿瘤学   546篇
  2023年   75篇
  2022年   60篇
  2021年   221篇
  2020年   172篇
  2019年   198篇
  2018年   200篇
  2017年   187篇
  2016年   178篇
  2015年   208篇
  2014年   254篇
  2013年   386篇
  2012年   474篇
  2011年   532篇
  2010年   259篇
  2009年   239篇
  2008年   420篇
  2007年   431篇
  2006年   387篇
  2005年   381篇
  2004年   317篇
  2003年   274篇
  2002年   287篇
  2001年   50篇
  2000年   48篇
  1999年   48篇
  1998年   50篇
  1997年   38篇
  1996年   33篇
  1995年   23篇
  1994年   24篇
  1993年   13篇
  1992年   24篇
  1991年   18篇
  1990年   21篇
  1989年   12篇
  1988年   21篇
  1987年   26篇
  1986年   14篇
  1985年   24篇
  1984年   17篇
  1983年   13篇
  1982年   11篇
  1979年   9篇
  1978年   8篇
  1977年   9篇
  1975年   10篇
  1974年   10篇
  1973年   8篇
  1970年   13篇
  1968年   9篇
排序方式: 共有6804条查询结果,搜索用时 203 毫秒
991.
992.
993.
994.

Background

Modern intrauterine contraception (IUC) is safe and highly effective, but is used by fewer than 4% of women in the United States. Once recommended only for women with at least one child, it is now recommended for most women regardless of parity or age.

Methods

This study used data representative of California women from 10 years of the California Women’s Health Survey (1997–2007) to describe how IUC users differ from women using other contraceptives, and assess changes in IUC users’ characteristics over time.

Findings

Overall 4.9% of women in California used IUC. Multivariable logistic regression modeling showed IUC users were more likely to be born outside the United States (odds ratio [OR], 1.7), have a college degree (OR, 1.5) or postgraduate degree (OR, 2.2), and be married (OR, 2.6) or in an unmarried partnership (OR, 2.4). IUC users were 71% less likely to be nulliparous (OR, 0.29). Use of IUC almost doubled over the study period from 4.0% to 7.2%, and this growth was accompanied by significant changes in user characteristics: Young women, women born in the United States, women without a college degree, and Asian women experienced the greatest increases. IUC use among nulliparous women did not increase.

Conclusion

IUC use in California is higher than the national average and growing. We found higher IUC use among ever-married women and foreign-born women, and disproportionately low use among nulliparous women. Efforts to inform women of IUC’s high effectiveness and safety, as well as efforts to ensure that health care providers have the necessary clinical skills, are timely and important.  相似文献   
995.
The purpose of this grounded theory study was to investigate how Danish HIV-positive persons live with their disease, focusing on HIV-related stressors. Using the Glaserian method, we analyzed textual data from in-depth interviews with 16 HIV-positive persons. Decisions about disclosure appeared to be a major concern and a determining factor for HIV-related stress. Consequently, we developed a substantive theory about disclosure decisions in which three different strategies could be identified: (a) disclosing to everyone (being open); (b) restricting disclosure (being partly open); and (c) disclosing to no one (being closed). Disclosure was a continuum; none of the three strategies automatically relieved HIV-related stress. The theory describes the main determinants and consequences of each strategy. Our study demonstrates the importance of recurrent individual considerations about disclosure choices and plans, and offers a theoretical basis for interventions designed to assist persons living with HIV to make the best possible individual decisions regarding disclosure, and thereby reduce HIV-related stress.  相似文献   
996.
997.
The genetic relatedness of mountain gorillas and humans has led to concerns about interspecies transmission of infectious agents. Human-to-gorilla transmission may explain human metapneumovirus in 2 wild mountain gorillas that died during a respiratory disease outbreak in Rwanda in 2009. Surveillance is needed to ensure survival of these critically endangered animals.  相似文献   
998.
999.
Current practice of sedation and anesthesia for patients undergoing pediatric congenital cardiac catheterization laboratory (PCCCL) procedures is known to vary among institutions, a multi‐society expert panel with representatives from the Congenital Heart Disease Council of the Society for Cardiovascular Angiography and Interventions (SCAI), the Society for Pediatric Anesthesia (SPA) and the Congenital Cardiac Anesthesia Society (CCAS) was convened to evaluate the types of sedation and personnel necessary for procedures performed in the PCCCL. The goal of this panel was to provide practitioners and institutions performing these procedures with guidance consistent with national standards and to provide clinicians and institutions with consensus‐based recommendations and the supporting references to encourage their application in quality improvement programs. Recommendations can neither encompass all clinical circumstances nor replace the judgment of individual clinicians in the management of each patient. The science of medicine is rooted in evidence, and the art of medicine is based on the application of this evidence to the individual patient. This expert consensus statement has adhered to these principles for optimal management of patients requiring sedation and anesthesia. What follows are recommendations for patient monitoring in the PCCCL regardless of whether minimal or no sedation is being used or general anesthesia is being provided by an anesthesiologist. © 2016 Wiley Periodicals Inc.  相似文献   
1000.
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