全文获取类型
收费全文 | 21378篇 |
免费 | 1708篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 153篇 |
儿科学 | 661篇 |
妇产科学 | 459篇 |
基础医学 | 2586篇 |
口腔科学 | 331篇 |
临床医学 | 2070篇 |
内科学 | 4825篇 |
皮肤病学 | 264篇 |
神经病学 | 1953篇 |
特种医学 | 768篇 |
外国民族医学 | 5篇 |
外科学 | 2774篇 |
综合类 | 485篇 |
现状与发展 | 1篇 |
一般理论 | 20篇 |
预防医学 | 2489篇 |
眼科学 | 440篇 |
药学 | 1724篇 |
中国医学 | 58篇 |
肿瘤学 | 1071篇 |
出版年
2023年 | 112篇 |
2022年 | 130篇 |
2021年 | 385篇 |
2020年 | 225篇 |
2019年 | 405篇 |
2018年 | 574篇 |
2017年 | 426篇 |
2016年 | 400篇 |
2015年 | 449篇 |
2014年 | 587篇 |
2013年 | 839篇 |
2012年 | 1242篇 |
2011年 | 1389篇 |
2010年 | 753篇 |
2009年 | 638篇 |
2008年 | 1241篇 |
2007年 | 1372篇 |
2006年 | 1252篇 |
2005年 | 1293篇 |
2004年 | 1247篇 |
2003年 | 1171篇 |
2002年 | 1104篇 |
2001年 | 560篇 |
2000年 | 638篇 |
1999年 | 475篇 |
1998年 | 204篇 |
1997年 | 180篇 |
1996年 | 148篇 |
1995年 | 118篇 |
1994年 | 135篇 |
1993年 | 117篇 |
1992年 | 270篇 |
1991年 | 244篇 |
1990年 | 214篇 |
1989年 | 202篇 |
1988年 | 163篇 |
1987年 | 171篇 |
1986年 | 148篇 |
1985年 | 151篇 |
1984年 | 110篇 |
1983年 | 104篇 |
1982年 | 100篇 |
1981年 | 88篇 |
1980年 | 76篇 |
1979年 | 142篇 |
1978年 | 98篇 |
1977年 | 92篇 |
1976年 | 76篇 |
1974年 | 80篇 |
1972年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Owens EB Hinshaw SP Kraemer HC Arnold LE Abikoff HB Cantwell DP Conners CK Elliott G Greenhill LL Hechtman L Hoza B Jensen PS March JS Newcorn JH Pelham WE Severe JB Swanson JM Vitiello B Wells KC Wigal T 《Journal of consulting and clinical psychology》2003,71(3):540-552
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. 相似文献
102.
103.
Elliott L Heederik D Marshall S Peden D Loomis D 《The Journal of allergy and clinical immunology》2005,116(1):127-132
BACKGROUND: Laboratory animal allergy is a common illness among workers exposed to laboratory animals and can progress to symptoms of asthma. OBJECTIVES: This study evaluates the continuum of disease from allergy symptoms to asthma symptoms in a dynamic cohort of workers exposed to animals in a pharmaceutical company. METHODS: Data arose from annual questionnaires administered to workers in a surveillance program established to monitor exposure to animals and the development of allergy. The life-table method was used to compare asthma-free survival between workers with and without symptoms of allergy. A Cox proportional hazards model was used to examine the effects of covariates on the development of asthma. RESULTS: A total of 603 workers contributed 2527.4 person-years to the study over the 12.3-year period. The probabilities of experiencing asthma symptoms by the 11th year of follow-up were 0.367 for workers with allergy symptoms and 0.052 for those without allergy symptoms. The hazard ratio for asthma symptoms when comparing workers with and without allergy symptoms was 7.39 (95% CI, 3.29-16.60) after adjustment for sex and family history of allergy. Female subjects developed asthma at a rate 3.4 times that of male subjects. CONCLUSIONS: This study supports the hypothesis that laboratory animal allergy symptoms are a major risk factor for the development of asthma. It also suggests a heightened risk of asthma for women who work with laboratory animals, a finding that has not been previously reported. 相似文献
104.
105.
106.
The majority of children who develop Type 1 diabetes under the age of 10-years-old show islet cell antibodies at levels of 40 or more units. Those who have lower levels (10-<40) usually have co-existent insulin autoantibodies. Of these children 85% have these criteria. When these criteria were applied to large groups of similarly aged children who were either first degree relatives of a type 1 diabetic or had no such family history, 3.8% and 0.38% respectively showed these criteria. The observed sensitivity of these characteristics children who develop diabetes in the subsequent 5 years is 79% for both groups. The calculated expected incidence of disease in the subsequent 10 years for these two groups is 2.15% and 0.215% respectively. This model of autoantibody prediction of diabetes in children thus applies equally well in terms of sensitivity and specificity to those with and without a family history of diabetes. 相似文献
107.
Survey of the Distribution of a Newly Characterized Receptor for Advanced Glycation End Products in Tissues 总被引:33,自引:2,他引:33 下载免费PDF全文
Jerold Brett Ann Marie Schmidt Shi Du Yan Yu Shan Zou Elliott Weidman David Pinsky Roman Nowygrod Michael Neeper Craig Przysiecki Alan Shaw Antonio Migheli David Stern 《The American journal of pathology》1993,143(6):1699-1712
Advanced glycation end products (AGEs), the final products of nonenzymatic glycation and oxidation of proteins, are found in the plasma and accumulate in the tissues during aging and at an accelerated rate in diabetes. A novel integral membrane protein, termed receptor for AGE (RAGE), forms a central part of the cell surface binding site for AGEs. Using monospecific, polyclonal antibody raised to human recombinant and bovine RAGE, immunostaining of bovine tissues showed RAGE in the vasculature, endothelium, and smooth muscle cells and in mononuclear cells in the tissues. Consistent with these data, RAGE antigen and mRNA were identified in cultured bovine endothelium, vascular smooth muscle, and monocyte-derived macrophages. RAGE antigen was also visualized in bovine cardiac myocytes as well as in cultures of neonatal rat cardiac myocytes and in neural tissue where motor neurons, peripheral nerves, and a population of cortical neurons were positive. In situ hybridization confirmed the presence of RAGE mRNA in the tissues, and studies with rat PC12 pheochromocytes indicated that they provide a neuronal-related cell culture model for examining RAGE expression. Pathological studies of human atherosclerotic plaques showed infiltration of RAGE-expressing cells in the expanded intima. These results indicate that RAGE is present in multiple tissues and suggest the potential relevance of AGE-RAGE interactions for modulating properties of the vasculature as well as neural and cardiac function, prominent areas of involvement in diabetes and in the normal aging process. 相似文献
108.
Potent inhibition of HIV-1 entry by (s4dU)35 总被引:2,自引:0,他引:2
Horváth A Tokés S Hartman T Watson K Turpin JA Buckheit RW Sebestyén Z Szöllosi J Benko I Bardos TJ Dunn JA Fésüs L Tóth FD Aradi J 《Virology》2005,334(2):214-223
109.
110.
Evaluation of three disk tests for identification of enterococci, leuconostocs, and pediococci. 总被引:2,自引:1,他引:2 下载免费PDF全文
Simple rapid tests for presumptive identification of catalase-negative non-beta-hemolytic cocci (i.e., enterococci, leuconostocs, and pediococci) have not previously been available. Seven hundred thirty-four strains of aerobic and facultatively anaerobic, catalase-negative, non-beta-hemolytic gram-positive cocci were tested for susceptibility to vancomycin (Vans) by a screening procedure and production of leucine aminopeptidase (LAPase) and pyrrolidonylarylamidase (PYRase) in disk tests. Three unique patterns of activity in response to the three disks (30 micrograms of vancomycin, PYRase, and LAPase) can be used to presumptively identify the vancomycin-resistant (Vanr) enterococci (Vanr and PYRase and LAPase positive), leuconostocs (Vanr and PYRase and LAPase negative), and pediococci (Vanr, PYRase negative, and LAPase positive). The results indicate that, together with Gram stain characteristics and the catalase test, the vancomycin, LAPase, and PYRase disk tests can be used to presumptively identify Vanr strains of enterococci as well as Leuconostoc and Pediococcus strains from human infections. 相似文献