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   3833642篇
  免费   274973篇
  国内免费   5902篇
耳鼻咽喉   54550篇
儿科学   126468篇
妇产科学   107191篇
基础医学   559446篇
口腔科学   109690篇
临床医学   349179篇
内科学   729399篇
皮肤病学   83820篇
神经病学   304504篇
特种医学   144418篇
外国民族医学   1032篇
外科学   570477篇
综合类   83226篇
现状与发展   14篇
一般理论   1496篇
预防医学   306988篇
眼科学   90985篇
药学   285743篇
  17篇
中国医学   7182篇
肿瘤学   198692篇
  2018年   40818篇
  2017年   30729篇
  2016年   34364篇
  2015年   39247篇
  2014年   55228篇
  2013年   84134篇
  2012年   114922篇
  2011年   122705篇
  2010年   72837篇
  2009年   68821篇
  2008年   116019篇
  2007年   123931篇
  2006年   124937篇
  2005年   121835篇
  2004年   116965篇
  2003年   112552篇
  2002年   109607篇
  2001年   164911篇
  2000年   169088篇
  1999年   143251篇
  1998年   42946篇
  1997年   37851篇
  1996年   38161篇
  1995年   36054篇
  1994年   33616篇
  1993年   31438篇
  1992年   113892篇
  1991年   111751篇
  1990年   109468篇
  1989年   106159篇
  1988年   98272篇
  1987年   96597篇
  1986年   91800篇
  1985年   87990篇
  1984年   66232篇
  1983年   57151篇
  1982年   34529篇
  1981年   31062篇
  1979年   62955篇
  1978年   45124篇
  1977年   38146篇
  1976年   36200篇
  1975年   39393篇
  1974年   47196篇
  1973年   45547篇
  1972年   43158篇
  1971年   40568篇
  1970年   37876篇
  1969年   36179篇
  1968年   33776篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
133.
134.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
135.
136.
137.
This study explored the relationship between active mediation, exposure to Daniel Tiger’s Neighborhood, and key indicators of preschoolers’ social and emotional development. One hundred and twenty-seven children aged 2–6 either watched or did not watch 10 episodes of Daniel Tiger’s Neighborhood over a two-week period. Results revealed that preschoolers who watched the program exhibited higher levels of empathy, self-efficacy, and emotion recognition when their regular TV-watching experiences are frequently accompanied by active mediation. This was especially true for younger preschoolers and preschoolers from low-income families. Implications for policy-makers, parents, producers of prosocial programming, and educators are discussed.  相似文献   
138.
On 8 April 2014, a US jury ordered Takeda and Eli Lilly to pay $9 bn in punitive damages after finding that they had concealed the cancer risks associated with pioglitazone. By contrast, on 28 August 2014, the long‐awaited outcome of the 10‐year Kaiser Permanente Northern California study was announced. That study was specifically designed to investigate whether patients exposed to pioglitazone were at an increased risk of bladder cancer and found no association; thus, at last, the controversial issue has been resolved. A review, in retrospect, of the story of the proposed link between pioglitazone and bladder cancer reveals flaws at every stage. In 2012, a BMJ editorial, in keeping with some other contemporary reports, stated ‘it can confidently be assumed that pioglitazone increases the risk of bladder cancer’. Examination of the information which led to such a statement shows that: 1) the pre‐clinical findings of bladder cancer in male rats is not indicative of human risk; 2) there is no association between bladder cancer and pioglitazone in randomized controlled trials, once cases that could not plausibly be related to treatment are removed; and 3) the observational studies that have suggested a link have over‐extrapolated from the data: pioglitazone‐treated patients had more risk factors for bladder cancer than those not treated with pioglitazone. Meanwhile careful study of randomized controlled trials shows evidence of cardiovascular benefit from pioglitazone in Type 2 diabetes, a condition which results, more than anything, in premature cardiovascular death and morbidity.  相似文献   
139.
140.
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