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   2955762篇
  免费   217325篇
  国内免费   4939篇
耳鼻咽喉   41443篇
儿科学   95537篇
妇产科学   81406篇
基础医学   432387篇
口腔科学   82126篇
临床医学   264339篇
内科学   570854篇
皮肤病学   64910篇
神经病学   235239篇
特种医学   112908篇
外国民族医学   813篇
外科学   449069篇
综合类   61698篇
现状与发展   12篇
一般理论   1118篇
预防医学   231307篇
眼科学   69125篇
药学   219060篇
  9篇
中国医学   5696篇
肿瘤学   158970篇
  2019年   24308篇
  2018年   33455篇
  2017年   25516篇
  2016年   28359篇
  2015年   32034篇
  2014年   45404篇
  2013年   68124篇
  2012年   93813篇
  2011年   99698篇
  2010年   59268篇
  2009年   56224篇
  2008年   93753篇
  2007年   99628篇
  2006年   100613篇
  2005年   97542篇
  2004年   92945篇
  2003年   89466篇
  2002年   86922篇
  2001年   132840篇
  2000年   136137篇
  1999年   114590篇
  1998年   31688篇
  1997年   27724篇
  1996年   27876篇
  1995年   28007篇
  1994年   25989篇
  1993年   24520篇
  1992年   89590篇
  1991年   87093篇
  1990年   85232篇
  1989年   82055篇
  1988年   75645篇
  1987年   74303篇
  1986年   69997篇
  1985年   67027篇
  1984年   50074篇
  1983年   42652篇
  1982年   25415篇
  1979年   46125篇
  1978年   32808篇
  1977年   27325篇
  1976年   26055篇
  1975年   28196篇
  1974年   34011篇
  1973年   32531篇
  1972年   30537篇
  1971年   28740篇
  1970年   26762篇
  1969年   25330篇
  1968年   23550篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Graefe's Archive for Clinical and Experimental Ophthalmology - To describe and present results after a technique for cataract surgery combined with explantation of an iris-fixated phakic...  相似文献   
42.
43.
44.
45.
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   
46.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
47.
48.
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   
49.
Bulletin of Experimental Biology and Medicine - We studied the effect of microalgae of various systematic groups added to the ration on the biochemical parameters of blood serum and liver and...  相似文献   
50.
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