全文获取类型
收费全文 | 3859986篇 |
免费 | 477016篇 |
国内免费 | 49784篇 |
专业分类
耳鼻咽喉 | 51766篇 |
儿科学 | 120872篇 |
妇产科学 | 98143篇 |
基础医学 | 623114篇 |
口腔科学 | 103682篇 |
临床医学 | 366200篇 |
内科学 | 711637篇 |
皮肤病学 | 97699篇 |
神经病学 | 330877篇 |
特种医学 | 154920篇 |
外国民族医学 | 497篇 |
外科学 | 597184篇 |
综合类 | 153470篇 |
现状与发展 | 23篇 |
一般理论 | 2396篇 |
预防医学 | 331882篇 |
眼科学 | 100498篇 |
药学 | 302724篇 |
22篇 | |
中国医学 | 56632篇 |
肿瘤学 | 182548篇 |
出版年
2021年 | 58082篇 |
2020年 | 40850篇 |
2019年 | 71044篇 |
2018年 | 84945篇 |
2017年 | 68306篇 |
2016年 | 72666篇 |
2015年 | 86460篇 |
2014年 | 120453篇 |
2013年 | 185274篇 |
2012年 | 109215篇 |
2011年 | 110729篇 |
2010年 | 131782篇 |
2009年 | 137592篇 |
2008年 | 94925篇 |
2007年 | 96141篇 |
2006年 | 106574篇 |
2005年 | 101080篇 |
2004年 | 105175篇 |
2003年 | 95112篇 |
2002年 | 84214篇 |
2001年 | 127298篇 |
2000年 | 119567篇 |
1999年 | 117434篇 |
1998年 | 72620篇 |
1997年 | 70863篇 |
1996年 | 69975篇 |
1995年 | 66022篇 |
1994年 | 60437篇 |
1993年 | 55857篇 |
1992年 | 89815篇 |
1991年 | 86202篇 |
1990年 | 82024篇 |
1989年 | 80518篇 |
1988年 | 75209篇 |
1987年 | 73865篇 |
1986年 | 70123篇 |
1985年 | 69600篇 |
1984年 | 60278篇 |
1983年 | 54730篇 |
1982年 | 48502篇 |
1981年 | 45553篇 |
1980年 | 42788篇 |
1979年 | 52197篇 |
1978年 | 43688篇 |
1977年 | 39746篇 |
1976年 | 36953篇 |
1975年 | 35592篇 |
1974年 | 36691篇 |
1973年 | 35367篇 |
1972年 | 32906篇 |
排序方式: 共有10000条查询结果,搜索用时 609 毫秒
71.
72.
Kara S. Tanaka MD Veronica R. Andaya BA Steven W. Thorpe MD Kenneth R. Gundle MD James B. Hayden MD Yee-Cheen Duong MD Raffi S. Avedian MD David G. Mohler MD Lee J. Morse MD Melissa N. Zimel MD Richard J. O'Donnell MD Andrew Fang MD Robert Lor Randall MD Tina H. Tran BS Christin New BA Rosanna L. Wustrack MD other members of Study Group FORCE 《Journal of surgical oncology》2023,127(1):148-158
73.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
74.
Boffa Joseph W. Tock Jamie L. Morabito Danielle M. Schmidt Norman B. 《Cognitive therapy and research》2022,46(5):1016-1029
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study... 相似文献
75.
76.
77.
目的 建立一种能够快速鉴定人参和西洋参的双重实时荧光PCR方法。方法 通过对人参属及其近似种基因序列的分析比对,设计特异性的引物探针,建立双重实时荧光PCR检测方法。PCR反应体系为Premix Ex Taq (Probe qPCR) 10 μL,人参上下游引物各0.5 μL,西洋参上下游引物各0.3 μL,人参与西洋参特异性探针各0.4 μL,DNA模板2 μL,灭菌去离子水补至20 μL。反应条件为95℃预变性30 s;然后以95℃变性5 s,60℃退火延伸30 s进行40个循环。应用该方法测试了27份DNA样品,包括7份人参、6份西洋参、4份人参与西洋参混合样、10份其他人参属样品及其他常见中药材样品的DNA,以确定该方法的特异性。将人参与西洋参样品DNA混合后10倍稀释成不同浓度后进行检测,用以确定该方法的灵敏度。结果 人参及西洋参样品均在特定的荧光通道下出现典型的阳性扩增曲线,人参与西洋参混合样品均同时出现两条阳性扩增曲线,其它对照样品及空白对照均没有出现阳性扩增曲线。灵敏度检测结果显示该方法检测人参及西洋参的最低检测限均为2 pg DNA/反应。结论 本实验建立的双重实时荧光PCR方法能够同时快速、准确、灵敏地鉴别出人参和西洋参。 相似文献
78.
79.
Victoria L. Parker Matthew C. Winter John A. Tidy Barry W. Hancock Julia E. Palmer Naveed Sarwar Baljeet Kaur Katie McDonald Xianne Aguiar Kamaljit Singh Nick Unsworth Imran Jabbar Allan A. Pacey Robert F. Harrison Michael J. Seckl 《International journal of cancer. Journal international du cancer》2023,152(5):986-997
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
80.
Triposkiadis Filippos Xanthopoulos Andrew Skoularigis John Starling Randall C. 《Heart failure reviews》2022,27(6):1991-2003
Heart Failure Reviews - The nitric oxide (NO)–guanylate cyclase (GC)–cyclic guanosine monophosphate (cGMP) pathway plays an important role in cardiovascular, pulmonary and renal... 相似文献