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   183990篇
  免费   12723篇
  国内免费   716篇
耳鼻咽喉   2584篇
儿科学   5096篇
妇产科学   3687篇
基础医学   23603篇
口腔科学   3713篇
临床医学   18241篇
内科学   38835篇
皮肤病学   2876篇
神经病学   18299篇
特种医学   6666篇
外国民族医学   14篇
外科学   27348篇
综合类   2545篇
一般理论   203篇
预防医学   14220篇
眼科学   5033篇
药学   12163篇
中国医学   206篇
肿瘤学   12097篇
  2023年   661篇
  2021年   2529篇
  2020年   1832篇
  2019年   2996篇
  2018年   3516篇
  2017年   2534篇
  2016年   2941篇
  2015年   3564篇
  2014年   5264篇
  2013年   8180篇
  2012年   11784篇
  2011年   12682篇
  2010年   7090篇
  2009年   6519篇
  2008年   11848篇
  2007年   12718篇
  2006年   12128篇
  2005年   12530篇
  2004年   11917篇
  2003年   11365篇
  2002年   10945篇
  2001年   1766篇
  2000年   1377篇
  1999年   1692篇
  1998年   2010篇
  1997年   1713篇
  1996年   1399篇
  1995年   1618篇
  1994年   1456篇
  1993年   1375篇
  1992年   1211篇
  1991年   1160篇
  1990年   1015篇
  1989年   990篇
  1988年   964篇
  1987年   879篇
  1986年   966篇
  1985年   1065篇
  1984年   1314篇
  1983年   1271篇
  1982年   1696篇
  1981年   1578篇
  1980年   1438篇
  1979年   865篇
  1978年   977篇
  1977年   852篇
  1976年   782篇
  1975年   655篇
  1974年   714篇
  1973年   579篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
3.
Medicine, Health Care and Philosophy - Clinical ethics consultants respond to a multitude of issues, ranging from the cognitive to the emotional. As such, ethics consultants must be prepared to...  相似文献   
4.
The Dutch Drug Rediscovery Protocol (DRUP) and the Australian Cancer Molecular Screening and Therapeutic (MoST) Program are similar nonrandomized, multidrug, pan-cancer trial platforms that aim to identify signals of clinical activity of molecularly matched targeted therapies or immunotherapies outside their approved indications. Here, we report results for advanced or metastatic cancer patients with tumors harboring cyclin D-CDK4/6 pathway alterations treated with CDK4/6 inhibitors palbociclib or ribociclib. We included adult patients that had therapy-refractory solid malignancies with the following alterations: amplifications of CDK4, CDK6, CCND1, CCND2 or CCND3, or complete loss of CDKN2A or SMARCA4. Within MoST, all patients were treated with palbociclib, whereas in DRUP, palbociclib and ribociclib were assigned to different cohorts (defined by tumor type and alteration). The primary endpoint for this combined analysis was clinical benefit, defined as confirmed objective response or stable disease ≥16 weeks. We treated 139 patients with a broad variety of tumor types; 116 with palbociclib and 23 with ribociclib. In 112 evaluable patients, the objective response rate was 0% and clinical benefit rate at 16 weeks was 15%. Median progression-free survival was 4 months (95% CI: 3-5 months), and median overall survival 5 months (95% CI: 4-6 months). In conclusion, only limited clinical activity of palbociclib and ribociclib monotherapy in patients with pretreated cancers harboring cyclin D-CDK4/6 pathway alterations was observed. Our findings indicate that monotherapy use of palbociclib or ribociclib is not recommended and that merging data of two similar precision oncology trials is feasible.  相似文献   
5.
6.
7.
8.
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
9.
10.
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