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   2514591篇
  免费   220971篇
  国内免费   6188篇
耳鼻咽喉   38500篇
儿科学   77742篇
妇产科学   65235篇
基础医学   339482篇
口腔科学   69071篇
临床医学   239950篇
内科学   509893篇
皮肤病学   54898篇
神经病学   214222篇
特种医学   101569篇
外国民族医学   886篇
外科学   396405篇
综合类   56616篇
现状与发展   74篇
一般理论   997篇
预防医学   197550篇
眼科学   58577篇
药学   179412篇
  4篇
中国医学   4398篇
肿瘤学   136269篇
  2018年   30825篇
  2017年   25258篇
  2016年   27808篇
  2015年   30647篇
  2014年   47075篇
  2013年   64605篇
  2012年   74381篇
  2011年   78008篇
  2010年   51805篇
  2009年   53378篇
  2008年   74481篇
  2007年   77405篇
  2006年   80331篇
  2005年   75950篇
  2004年   72643篇
  2003年   69374篇
  2002年   68645篇
  2001年   115743篇
  2000年   119155篇
  1999年   101127篇
  1998年   30980篇
  1997年   28403篇
  1996年   28146篇
  1995年   27221篇
  1994年   24791篇
  1993年   22826篇
  1992年   80522篇
  1991年   77541篇
  1990年   74466篇
  1989年   71822篇
  1988年   66711篇
  1987年   65542篇
  1986年   62088篇
  1985年   59040篇
  1984年   44708篇
  1983年   38096篇
  1982年   23307篇
  1981年   20711篇
  1980年   19386篇
  1979年   41556篇
  1978年   29275篇
  1977年   24698篇
  1976年   23039篇
  1975年   24200篇
  1974年   29829篇
  1973年   28241篇
  1972年   26487篇
  1971年   24332篇
  1970年   22948篇
  1969年   21154篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
132.
Clinical Oral Investigations - The aims of this study are to assess different saliva substitutes for their efficacy to lubricate the oral cavity, and to relate this oral lubrication to the ability...  相似文献   
133.
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   
134.
Obtaining accurate assessment data from adolescents in treatment aids clinical decision making and facilitates more accurate outcome evaluations. However, findings could be biased due to underreported substance use and mental health symptoms. This article compares self-reports of youth in non-White matched client–assessor dyads and those in nonmatched dyads. There were no differences on self-reported substance use, but matched youth reported significantly fewer attention deficit/hyperactivity disorder symptoms versus the comparison group. One possible reason for these findings is the effect of in-group stereotype threat. Future studies should examine the potential effect that in-group stereotyping and perceived racism have on the therapeutic relationship.  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.
139.
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   
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