全文获取类型
收费全文 | 2957篇 |
免费 | 118篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 34篇 |
妇产科学 | 61篇 |
基础医学 | 342篇 |
口腔科学 | 27篇 |
临床医学 | 341篇 |
内科学 | 773篇 |
皮肤病学 | 50篇 |
神经病学 | 278篇 |
特种医学 | 126篇 |
外科学 | 427篇 |
综合类 | 7篇 |
一般理论 | 2篇 |
预防医学 | 121篇 |
眼科学 | 14篇 |
药学 | 248篇 |
中国医学 | 3篇 |
肿瘤学 | 235篇 |
出版年
2024年 | 3篇 |
2023年 | 10篇 |
2022年 | 36篇 |
2021年 | 70篇 |
2020年 | 27篇 |
2019年 | 46篇 |
2018年 | 59篇 |
2017年 | 46篇 |
2016年 | 46篇 |
2015年 | 67篇 |
2014年 | 89篇 |
2013年 | 115篇 |
2012年 | 237篇 |
2011年 | 240篇 |
2010年 | 113篇 |
2009年 | 111篇 |
2008年 | 229篇 |
2007年 | 250篇 |
2006年 | 197篇 |
2005年 | 211篇 |
2004年 | 221篇 |
2003年 | 197篇 |
2002年 | 167篇 |
2001年 | 19篇 |
2000年 | 10篇 |
1999年 | 25篇 |
1998年 | 47篇 |
1997年 | 36篇 |
1996年 | 26篇 |
1995年 | 33篇 |
1994年 | 19篇 |
1993年 | 12篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 8篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1978年 | 2篇 |
1977年 | 1篇 |
排序方式: 共有3107条查询结果,搜索用时 15 毫秒
61.
The serum of a patient who developed a posttransfusion purpura contained antibodies directed against a previously undescribed platelet antigen Lek a. The antiplatelet activity was present in the IgG fraction and was detected by immunofluorescence, 51Cr lysis and 14C-serotonin release. The frequency of the Lek a phenotype in the French population is 98.18%. Lek a does not appear to be sex-linked and seems to be closely related to the Bak a antigen. The Lek a antigen is not expressed on thrombasthenic platelets but is found on platelets from patients with the Bernard-Soulier syndrome which suggests that this antigen is carried by platelet glycoproteins IIb and/or IIIa. 相似文献
62.
Philippe Moreau Marie-France Kergueris NoE¨l Milpied Stéphane Le Tortorec Béatrice Mahé Claude-Eric Bulabois Marie-JosÉ Rapp Claude Larousse RÉgis Bataille & Jean-Luc Harousseau 《British journal of haematology》1996,95(3):527-530
We studied the pharmacokinetics and toxicity of 220 mg/m2 melphalan (HDM 220) followed by autologous stem cell transplantation in 16 patients with advanced haematological malignancies. Pharmacokinetic parameters (mean values of steady-state volume of distribution 14.6 l/m2 , total body clearance 313 ml/min/m2 , elimination half-life 46 min) were the same as those of 140 or 200 mg/m2 melphalan in previous reports. HDM 220 was feasible. Extramedullary toxicity was mainly W.H.O. grade 4 mucositis (13/16 patients). The median duration of 41 d (10, not reached) of thrombocytopenia <25 × 109 /l was long. In multiple myeloma the response rate was 89% in heavily pretreated patients, suggesting that HDM 220 could be considered earlier in the course of the disease as an alternative consolidation therapy. 相似文献
63.
Laurent Macchi Patrick Rispal Gisèle Clofent-Sanchez Jean-Luc Pellegrin Paquita Nurden Bernard Leng & Alan T. Nurden 《British journal of haematology》1997,98(2):336-341
The role of antiphospholipid antibodies in the pathogenesis of the thrombocytopenia observed during primary antiphospholipid antibody syndrome (APAS) and systemic lupus erythematosus (SLE) remains controversial. We have used the MAIPA test to examine the frequency and specificity of anti-platelet antibodies directed against the major platelet membrane glycoproteins (GP IIb–IIIa, GP Ib–IX, GP Ia–IIa and GP IV) in patients where SLE and APAS were associated or not with thrombocytopenia. Results were compared with a series of 26 ITP patients, 46% of whom were shown to possess anti-platelet antibodies directed against one or more of the platelet surface glycoproteins. When APAS was associated with thrombocytopenia, 7/10 patients possessed antibodies against GP IIb–IIIa and/or GP Ib–IX. For SLE patients with thrombocytopenia, 6/10 patients were shown to have antiplatelet antibodies against GP IIb–IIIa, GP Ib–IX or GP IV. In contrast, for APAS ( n =11) and SLE patients ( n =11) without thrombocytopenia, only one patient had an antibody directed against GP IIb–IIIa and one patient had an antibody to GP IV. Our results suggest that antibodies directed against major platelet membrane glycoproteins may play a role in the thrombocytopenia that is seen during SLE and APAS. 相似文献
64.
Hermida JS Kubala M Lescure FX Delonca J Clerc J Otmani A Jarry G Rey JL 《American heart journal》2004,148(2):312-317
Background
In order to assess the preventive effects of right atrial septal pacing on atrial fibrillation (AF) in patients with sinus node dysfunction, we conducted a prospective randomized controlled study in patients requiring atrial pacing.Methods
The inclusion criterion was the presence of a sinus node dysfunction with or without episodes of AF. Pacing sites were randomized to either the right atrial septum or appendage. Patients with permanent AF or with atrioventricular (AV) block without sinus node dysfunction were excluded. Patients were discharged at a pacing rate of 65 beats per minute after setting of the optimal AV delay. The antiarrhythmic therapy remained unchanged until the first recurrence of AF. Sequential analyses were performed with the triangular test.Results
Mean baseline characteristics were not different between the septum (n = 57) and the appendage (n = 67) groups. The triangular test evidenced a lack of effect of septal pacing at the last sequential analysis. The rates of AF-free survival were not different between the septum and the appendage group (65% vs 64%, P = .28).In the subgroup of patients with at least 1 episode of AF 3 months before pacing, AF-free survival was increased by atrial septal pacing (70% vs 40%, P = .018). The mean follow-up was 16 ± 13 months (range, 1-54).Conclusions
Atrial septal pacing does not have a preventive effect on the occurrence of AF in patient requiring atrial pacing for sinus node dysfunction. Subgroup analysis suggests that atrial septal pacing may benefit patients with ≥1 episode of AF in the 3 months preceding pacing. 相似文献65.
66.
Immature dendritic cell transdifferentiation into osteoclasts: a novel pathway sustained by the rheumatoid arthritis microenvironment 总被引:10,自引:0,他引:10 下载免费PDF全文
Rivollier A Mazzorana M Tebib J Piperno M Aitsiselmi T Rabourdin-Combe C Jurdic P Servet-Delprat C 《Blood》2004,104(13):4029-4037
Dendritic cells (DCs), the mononuclear cells that initiate immune response, and osteoclasts, the multinucleated bone-resorbing cells, are derived from monocyte/macrophage precursor cells. Granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor (M-CSF) reciprocally regulate the differentiation of both lineages in mice. Using human monocyte-derived DCs generated in vitro, we show that immature DCs transdifferentiate into functional osteoclasts (OCs) in the presence of M-CSF and receptor activator of nuclear factor-kappaB ligand (RANKL). Transdifferentiation operates through fusion of intermediate adherent bipolar fusiform mononuclear cells expressing CD14, CD1a, and RANKL and able to induce RANKL(+) T-cell proliferation. Surprisingly, DC fusion in vitro is faster and more efficient than monocyte fusion to form multinucleated giant cells. The transdifferentiation process reported here supports the existence of a high cellular plasticity within differentiated myeloid phagocytes. Importantly, this process is greatly enhanced by rheumatoid arthritis synovial fluid and involves proinflammatory cytokines such as interleukin 1 or tumor necrosis factor alpha, as well as components of the extracellular matrix such as hyaluronic acid. Our data therefore suggest that DC-derived OCs may be directly involved in the osteolytic lesions observed in human inflammatory bone diseases such as rheumatoid arthritis or in particular forms of Langerhans cell histiocytosis, characterized by accumulation of immature skin DCs and chronic lytic bone lesions. 相似文献
67.
Daria Soroka Inès Li de la Sierra-Gallay Vincent Dubée Sébastien Triboulet Herman van Tilbeurgh Fabrice Compain Lluis Ballell David Barros Jean-Luc Mainardi Jean-Emmanuel Hugonnet Michel Arthur 《Antimicrobial agents and chemotherapy》2015,59(9):5714-5720
Combinations of β-lactams with clavulanate are currently being investigated for tuberculosis treatment. Since Mycobacterium tuberculosis produces a broad spectrum β-lactamase, BlaC, the success of this approach could be compromised by the emergence of clavulanate-resistant variants, as observed for inhibitor-resistant TEM variants in enterobacteria. Previous analyses based on site-directed mutagenesis of BlaC have led to the conclusion that this risk was limited. Here, we used a different approach based on determination of the crystal structure of β-lactamase BlaMAb of Mycobacterium abscessus, which efficiently hydrolyzes clavulanate. Comparison of BlaMAb and BlaC allowed for structure-assisted site-directed mutagenesis of BlaC and identification of the G132N substitution that was sufficient to switch the interaction of BlaC with clavulanate from irreversible inactivation to efficient hydrolysis. The substitution, which restored the canonical SDN motif (SDG→SDN), allowed for efficient hydrolysis of clavulanate, with a more than 104-fold increase in kcat (0.41 s−1), without affecting the hydrolysis of other β-lactams. Mass spectrometry revealed that acylation of BlaC and of its G132N variant by clavulanate follows similar paths, involving sequential formation of two acylenzymes. Decarboxylation of the first acylenzyme results in a stable secondary acylenzyme in BlaC, whereas hydrolysis occurs in the G132N variant. The SDN/SDG polymorphism defines two mycobacterial lineages comprising rapidly and slowly growing species, respectively. Together, these results suggest that the efficacy of β-lactam–clavulanate combinations may be limited by the emergence of resistance. β-Lactams active without clavulanate, such as faropenem, should be prioritized for the development of new therapies. 相似文献
68.
69.
Dessy C Saliez J Ghisdal P Daneau G Lobysheva II Frérart F Belge C Jnaoui K Noirhomme P Feron O Balligand JL 《Circulation》2005,112(8):1198-1205