全文获取类型
收费全文 | 913758篇 |
免费 | 65299篇 |
国内免费 | 3468篇 |
专业分类
耳鼻咽喉 | 12604篇 |
儿科学 | 29014篇 |
妇产科学 | 26354篇 |
基础医学 | 128154篇 |
口腔科学 | 24902篇 |
临床医学 | 76813篇 |
内科学 | 185164篇 |
皮肤病学 | 19175篇 |
神经病学 | 72052篇 |
特种医学 | 36928篇 |
外国民族医学 | 339篇 |
外科学 | 143648篇 |
综合类 | 22128篇 |
现状与发展 | 7篇 |
一般理论 | 249篇 |
预防医学 | 65772篇 |
眼科学 | 20391篇 |
药学 | 65599篇 |
24篇 | |
中国医学 | 2974篇 |
肿瘤学 | 50234篇 |
出版年
2018年 | 9633篇 |
2017年 | 7766篇 |
2016年 | 8239篇 |
2015年 | 9509篇 |
2014年 | 13322篇 |
2013年 | 20184篇 |
2012年 | 26997篇 |
2011年 | 28720篇 |
2010年 | 17542篇 |
2009年 | 16611篇 |
2008年 | 27055篇 |
2007年 | 28560篇 |
2006年 | 28674篇 |
2005年 | 28096篇 |
2004年 | 26798篇 |
2003年 | 26024篇 |
2002年 | 25468篇 |
2001年 | 41703篇 |
2000年 | 42823篇 |
1999年 | 36517篇 |
1998年 | 10097篇 |
1997年 | 9288篇 |
1996年 | 9177篇 |
1995年 | 8526篇 |
1994年 | 8171篇 |
1993年 | 7640篇 |
1992年 | 28253篇 |
1991年 | 27023篇 |
1990年 | 26444篇 |
1989年 | 25382篇 |
1988年 | 23583篇 |
1987年 | 23185篇 |
1986年 | 22264篇 |
1985年 | 21163篇 |
1984年 | 15813篇 |
1983年 | 13481篇 |
1982年 | 8089篇 |
1979年 | 14591篇 |
1978年 | 10209篇 |
1977年 | 8627篇 |
1976年 | 8148篇 |
1975年 | 8961篇 |
1974年 | 10697篇 |
1973年 | 10183篇 |
1972年 | 9661篇 |
1971年 | 8917篇 |
1970年 | 8584篇 |
1969年 | 8025篇 |
1968年 | 7684篇 |
1967年 | 7086篇 |
排序方式: 共有10000条查询结果,搜索用时 312 毫秒
1.
Kinase alterations are increasingly recognised as oncogenic drivers in mesenchymal tumours. Infantile fibrosarcoma and the related renal tumour, congenital mesoblastic nephroma, were among the first solid tumours shown to harbour recurrent tyrosine kinase fusions, with the canonical ETV6::NTRK3 fusion identified more than 20 years ago. Although targeted testing has long been used in diagnosis, the advent of more robust sequencing techniques has driven the discovery of kinase alterations in an array of mesenchymal tumours. As our ability to identify these genetic alterations has improved, as has our recognition and understanding of the tumours that harbour these alterations. Specifically, this study will focus upon mesenchymal tumours harbouring NTRK or other kinase alterations, including tumours with an infantile fibrosarcoma-like appearance, spindle cell tumours resembling lipofibromatosis or peripheral nerve sheath tumours and those occurring in adults with a fibrosarcoma-like appearance. As publications describing the histology of these tumours increase so, too, do the variety kinase alterations reported, now including NTRK1/2/3, RET, MET, RAF1, BRAF, ALK, EGFR and ABL1 fusions or alterations. To date, these tumours appear locally aggressive and rarely metastatic, without a clear link between traditional features used in histological grading (e.g. mitotic activity, necrosis) and outcome. However, most of these tumours are amenable to new targeted therapies, making their recognition of both diagnostic and therapeutic import. The goal of this study is to review the clinicopathological features of tumours with NTRK and other tyrosine kinase alterations, discuss the most common differential diagnoses and provide recommendations for molecular confirmation with associated treatment implications. 相似文献
2.
目的 了解我国老年人中医证候分布特征,为中医药辨治老年人提供参考依据。方法 系统检索中国知识基础设施(CNKI)、中文科技期刊数据库(CCD)、万方数据资源系统数据库(CSPD),纳入研究对象为老年人的临床流行病学调查研究文献,对其调查目的、调查疾病及调查结果等进行描述统计。结果 ①最终纳入168篇文献,其中2010至2020年之间发表138篇(82.14%);调查地区涵盖全国28个省市自治区,共纳入43948例老年人,累计覆盖340个研究中心;②主要研究结果显示,老年人中医证候阴虚阳亢证(10.05%)>血瘀证(9.5%)>痰浊(湿)证(8.91%)>阴阳两虚证(4.98%)>痰瘀互结证(4.96%);单元证分布阴虚证(14.70%)>痰证(11.22%)>气虚证(7.15%)>肾虚证(4.72%)>血瘀证(4.18%);涉及病变脏腑肾>肝>脾>肺>心。结论 根据统计结果,可以看出老年人证候分布虚证多于实证,虚证中又以阴虚证、气虚证最为多见,实证常见血瘀证、痰浊(湿)证等,且多见痰瘀互结证;老年人五脏皆损,其中又以肾、肝、脾功能失调最为突出。 相似文献
3.
Michels Guido Horn Rudolf Helfen Andreas Hagendorff Andreas Jung Christian Hoffmann Beatrice Jaspers Natalie Kinkel Horst Greim Clemens-Alexander Knebel Fabian Bauersachs Johann Busch Hans-Jörg Kiefl Daniel Spiel Alexander O. Marx Gernot Dietrich Christoph F. 《Der Anaesthesist》2022,71(4):307-310
Die Anaesthesiologie - 相似文献
4.
5.
6.
7.
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
8.
Vilar-Compte Mireya Gaitán-Rossi Pablo Félix-Beltrán Lucía Bustamante Arturo V. 《Journal of immigrant and minority health / Center for Minority Public Health》2022,24(1):65-77
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to... 相似文献
9.
10.
A Coupled FEM-BEM Approach for the Solution of the Free-Boundary Axi-Symmetric Plasma Equilibrium Problem 下载免费PDF全文
M. Bonotto D. Abate P. Bettini & F. Villone 《Communications In Computational Physics》2022,31(1):27-59
In this paper we present a coupled Finite Element Method – Boundary Element Method (FEM-BEM) approach for the solution of the free-boundary axi-symmetric
plasma equilibrium problem. The proposed method, obtained from an improvement
of the Hagenow-Lackner coupling method, allows to efficiently model the equilibrium
problem in unbounded domains by discretizing only the plasma region; the external
conductors can be modelled either as 2D or 3D models, according to the problem of interest. The paper explores different iterative methods for the solution of the nonlinear
Grad-Shafranov equation, such as Picard, Newton-Raphson and Newton-Krylov, in order to provide a robust and reliable tool, able to handle large-scale problems (e.g. high
resolution equilibria). This method has been implemented in the FRIDA code (FRee-boundary Integro-Differential Axisimmetric – https://github.
om/matteobonotto/
FRIDA), together with a suitable Adaptive Integration Technique (AIT) for the computation of the source term. FRIDA has been successfully tested and validated against
experimental data from RFX-mod device, and numerical equilibria of an ITER-like device. 相似文献