全文获取类型
收费全文 | 411篇 |
免费 | 21篇 |
国内免费 | 9篇 |
专业分类
儿科学 | 31篇 |
妇产科学 | 3篇 |
基础医学 | 31篇 |
口腔科学 | 10篇 |
临床医学 | 28篇 |
内科学 | 171篇 |
皮肤病学 | 8篇 |
神经病学 | 5篇 |
特种医学 | 62篇 |
外科学 | 30篇 |
综合类 | 8篇 |
预防医学 | 8篇 |
眼科学 | 4篇 |
药学 | 18篇 |
肿瘤学 | 24篇 |
出版年
2023年 | 2篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 9篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 18篇 |
2012年 | 14篇 |
2011年 | 13篇 |
2010年 | 20篇 |
2009年 | 21篇 |
2008年 | 14篇 |
2007年 | 12篇 |
2006年 | 14篇 |
2005年 | 20篇 |
2004年 | 18篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 12篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 22篇 |
1997年 | 19篇 |
1996年 | 20篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 13篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1975年 | 1篇 |
1948年 | 2篇 |
1932年 | 1篇 |
1925年 | 1篇 |
1924年 | 1篇 |
排序方式: 共有441条查询结果,搜索用时 15 毫秒
31.
The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies. 相似文献
32.
FcR gamma-chain is essential for both surface expression and function of human Fc gamma RI (CD64) in vivo 总被引:5,自引:0,他引:5
van Vugt MJ; Heijnen AF; Capel PJ; Park SY; Ra C; Saito T; Verbeek JS; van de Winkel JG 《Blood》1996,87(9):3593-3599
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo. 相似文献
33.
Moubarak G Messali A Extramiana F Leenhardt A 《Annales de cardiologie et d'angeiologie》2010,59(Z1):S14-S18
Atrial fibrillation (AF) is the most frequent cardiac arrhythmia and its prevalence rises with age. AF may cause stroke and heart failure but the relationship between AF and mortality is less clear. It is difficult to determine if cardiovascular events in patients with AF are attributable to the arrhythmia itself or if they are merely related to the comorbidities frequently associated with AF. Review of the literature suggests that lone AF (without structural heart disease), a rare clinical entity except in young patients, is not an independent risk factor for mortality. On the other hand, if illnesses usually associated with AF are present (hypertension, heart failure...), AF has a negative impact on outcome in terms of survival and morbidity. Current antiarrhythmic medications have not shown reduction in mortality of AF patients, but new agents and catheter ablation are promising paths to explore in order to decrease AF burden. 相似文献
34.
CE Vitor CP Figueiredo DB Hara AF Bento TL Mazzuco JB Calixto 《British journal of pharmacology》2009,157(6):1034-1044
Background and purpose:
α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.Experimental approach:
Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)Key results:
TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.Conclusions and implications:
Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease. 相似文献35.
36.
37.
38.
39.
Célia Lloret Linares Didier Troisvallets Pierre Sellier André Aurengo Laurence Leenhardt 《Medical oncology (Northwood, London, England)》2010,27(3):756-759
Patients with acquired immunodeficiency syndrome (AIDS) have an increased risk of malignancies such as Kaposi’s sarcoma, primary
central nervous system lymphoma, non-Hodgkin’s lymphoma, and cervical cancer, but the relative risk of other malignancies
such as papillary thyroid carcinoma (PTC) is not well documented. The report describes the case of a 52-year-old HIV-infected
Haitian male who presented with PTC. A post 131I therapy whole body scan (WBS) showed abnormal uptake in several areas indicating the presence of a number of micro-metastases.
Our case raises the question not only as to the role of HIV infection in predisposition to PTC, but also how it alters the
clinical course of the tumor. 相似文献
40.