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   245711篇
  免费   16129篇
  国内免费   1017篇
耳鼻咽喉   2612篇
儿科学   6459篇
妇产科学   4591篇
基础医学   30756篇
口腔科学   4459篇
临床医学   25255篇
内科学   51624篇
皮肤病学   3407篇
神经病学   24707篇
特种医学   10426篇
外国民族医学   15篇
外科学   38552篇
综合类   2701篇
现状与发展   1篇
一般理论   188篇
预防医学   17457篇
眼科学   6020篇
药学   16388篇
  1篇
中国医学   342篇
肿瘤学   16896篇
  2023年   1274篇
  2022年   1944篇
  2021年   5578篇
  2020年   3198篇
  2019年   5270篇
  2018年   6327篇
  2017年   4673篇
  2016年   5079篇
  2015年   6031篇
  2014年   8716篇
  2013年   11806篇
  2012年   18160篇
  2011年   18905篇
  2010年   10546篇
  2009年   9718篇
  2008年   16552篇
  2007年   17455篇
  2006年   16920篇
  2005年   16788篇
  2004年   15765篇
  2003年   14397篇
  2002年   13746篇
  2001年   2074篇
  2000年   1554篇
  1999年   2130篇
  1998年   2922篇
  1997年   2321篇
  1996年   2001篇
  1995年   1851篇
  1994年   1625篇
  1993年   1557篇
  1992年   1069篇
  1991年   1004篇
  1990年   841篇
  1989年   817篇
  1988年   744篇
  1987年   654篇
  1986年   688篇
  1985年   737篇
  1984年   962篇
  1983年   835篇
  1982年   1098篇
  1981年   1019篇
  1980年   880篇
  1979年   518篇
  1978年   558篇
  1977年   481篇
  1976年   442篇
  1975年   331篇
  1974年   334篇
排序方式: 共有10000条查询结果,搜索用时 375 毫秒
1.
European Surgery - Large skin defects caused by trauma (e.g., burns) or due to other reasons (e.g., tumor-related skin resections) require sufficient skin replacement. The constant improvement of...  相似文献   
2.
Die Anaesthesiologie - Phantomschmerzen haben eine hohe Prävalenz nach Majoramputationen und sind mit einer zusätzlichen Einschränkung der Lebensqualität verbunden....  相似文献   
3.
4.
5.
6.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
7.
8.
Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized.  相似文献   
9.
10.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  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