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   12853篇
  免费   947篇
  国内免费   46篇
耳鼻咽喉   83篇
儿科学   518篇
妇产科学   455篇
基础医学   1485篇
口腔科学   365篇
临床医学   1365篇
内科学   3127篇
皮肤病学   330篇
神经病学   857篇
特种医学   683篇
外国民族医学   3篇
外科学   1707篇
综合类   192篇
一般理论   7篇
预防医学   972篇
眼科学   416篇
药学   674篇
  1篇
中国医学   7篇
肿瘤学   599篇
  2021年   137篇
  2019年   137篇
  2018年   196篇
  2017年   162篇
  2016年   145篇
  2015年   182篇
  2014年   241篇
  2013年   377篇
  2012年   463篇
  2011年   495篇
  2010年   341篇
  2009年   337篇
  2008年   465篇
  2007年   463篇
  2006年   498篇
  2005年   508篇
  2004年   461篇
  2003年   437篇
  2002年   436篇
  2001年   443篇
  2000年   399篇
  1999年   347篇
  1998年   203篇
  1997年   211篇
  1996年   205篇
  1995年   163篇
  1994年   170篇
  1993年   193篇
  1992年   353篇
  1991年   334篇
  1990年   301篇
  1989年   335篇
  1988年   297篇
  1987年   301篇
  1986年   268篇
  1985年   244篇
  1984年   184篇
  1983年   170篇
  1982年   113篇
  1981年   132篇
  1980年   122篇
  1979年   178篇
  1978年   143篇
  1977年   138篇
  1976年   111篇
  1975年   99篇
  1974年   116篇
  1973年   115篇
  1972年   97篇
  1970年   96篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
74.
The alpha-adrenergic agonist oxymetazoline was compared to cocaine and to lidocaine with epinephrine with respect to prevention of epistaxis on nasotracheal intubation. The nares of three groups of 14 patients each were topically pretreated with 4% lidocaine with 1:100,000 epinephrine (group 1), 10% cocaine (group 2), or 0.05% oxymetazoline (group 3) prior to nasotracheal intubation. After intubation, epistaxis was estimated on a scale of 0 to 3, with 0 indicating no bleeding, 1 representing blood on the nasotracheal tube only, 2 indicating blood pooling in the pharynx, and 3 representing blood in the pharynx sufficient to impede intubation. Only 29% of the patients in group 1 displayed no bleeding, whereas 57% of those in group 2 and 86% of those in group 3 had no bleeding. Nonparametric analysis showed a statistically significant difference (p less than 0.013) between oxymetazoline and lidocaine with epinephrine. In addition, heart rate (HR) and blood pressure (BP) were examined prior to administration of the medications; at 5 minutes, 10 minutes, and 15 minutes after administration of the medications; and after intubation. No significant differences were noted (p greater than 0.05) between the medications except for a slightly higher systolic BP for cocaine than for lidocaine with epinephrine at 15 minutes. The results of this double-blind, randomized trial demonstrate that the alpha-adrenergic agonist oxymetazoline is as effective as cocaine, and more effective than lidocaine with epinephrine, for the prevention of epistaxis associated with nasotracheal intubation.  相似文献   
75.
Thirty-five posters were presented at the Workshop on Brain Uptake And Utilization Of Fatty Acids, Lipids, and Lipoproteins. They were grouped into four categories: (1) mechanisms of lipid uptake and transport to the brain, (2) lipoproteins and polyunsaturated fatty acids, (3) eicosanoids in brain function, and (4) fatty acids and lipids in brain disorders. This article summarizes the highlights of the research presented in these posters. The individual abstracts follow these synopses.  相似文献   
76.
77.
Isolated gastric sarcoidosis. Unique remnant of disseminated disease   总被引:1,自引:0,他引:1  
Isolated granulomatous disease was identified in a gastrectomy specimen after a gastrointestinal hemorrhage in a 61-year-old white woman. She died postoperatively. No other areas of granulomatous tissue were identified at autopsy. Ten years previously, pulmonary sarcoidosis was proven on lung biopsy. Conceivable, other reported cases of unexplained "idiopathic" granulomatous disease of the stomach may represent residua of prior disseminated sarcoidosis.  相似文献   
78.
Sir Martin Roth has stated, "where there is depression, there is hope," to emphasize the fact that depression can be a treatable source of excess disability, even when it is superimposed upon irreversible chronic medical illness. Both the potential benefits and the risks of antidepressant medications are increased in the frail elderly. This article presents an approach toward defining who should be treated and for ensuring that elderly patients receive adequate treatment.  相似文献   
79.
Graft-versus-host disease (GVHD) has been evaluated in partially inbred miniature swine in order to study this complication of allogeneic bone marrow transplantation (BMT) in a major histocompatibility complex (MHC) genetically defined large animal model. Bone marrow from MHC homozygous ("parental") swine was injected into irradiated (900 rads total-body irradiation) MHC heterozygous ("F1") swine that shared one haplotype with the donor. All 18 animals successfully engrafted with donor bone marrow, and 17 of these developed skin rash of varying intensity depending on the extent of T cell depletion of infused marrow. Of 18 animals, 8 received undepleted bone marrow from exsanguinated donors and 2 also received additional peripheral blood lymphocytes (PBL) as a source of mature T cells. All 8 showed a moderate-to-severe rash, and the 2 pigs that received additional donor PBL developed the most severe rash. The cutaneous eruption seen in this model clinically, histologically, and immunologically resembled human GVHD. Two protocols of T cell depletion of donor bone marrow by antiporcine T cell monoclonal antibodies plus complement were tested for their effect on development of GVHD. The combination of two monoclonal antibodies, 74-12-4 (PT4) and 76-2-11 (PT8), had a marginal effect on the subsequent development of cutaneous manifestations of GVHD. However, treatment of the donor marrow by a combination of three monoclonal antibodies--PT4, PT8, and MSA4 (PT11)--effectively decreased the severity of the GVHD skin rash. These results indicate that (1) the GVHD associated with allogeneic bone marrow transplantation in swine is dependent on T cells in the marrow; (2) effective T cell depletion of donor marrow by monoclonal antibodies and complement does not prevent engraftment; and (3) this swine GVHD model, which allows study with F1 and homozygous parental combinations in an MHC genetically defined large animal, is particularly useful for the understanding of GVHD pathogenesis, prevention, and treatment.  相似文献   
80.
Experiments were designed to evaluate the effect of recombinant IL-2 on growth of hemopoietic precursors from different sources (normal cord blood and bone marrow, and PB from CGL patients). For this purpose, combined cell sorting techniques and multipotent colony forming cell assays were used. A monoclonal antibody BI-3C5, which recognizes an antigen present on early lympho-myeloid cells as well as on all colony forming cells (CFU-GEMM assay), was used to enrich the studied populations. Double colour immunofluorescence techniques were performed to analyse the expression of Tac antigen on early progenitors. The results showed that rIL-2 had a stimulatory effect on growth of enriched progenitors from the three sources and surprisingly that addition of anti-Tac did not abolish this effect. On the contrary, anti-Tac enhanced even more growth of these sorted BI-3C5 precursors, suggesting a ligand action of the antibody. More interestingly, a low percentage of cord cells (1 in 1000) expressed both BI-3C5 and Tac antigens. The vast majority of cells did not concomitantly express both markers. The double labelled cells had a lymphoid-like morphology, high nucleus/cytoplasmic ratio and 2-3 nucleoli. The results will be discussed focusing on early and late "stem" cell growth.  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