全文获取类型
收费全文 | 934篇 |
免费 | 59篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 39篇 |
妇产科学 | 5篇 |
基础医学 | 97篇 |
口腔科学 | 44篇 |
临床医学 | 71篇 |
内科学 | 170篇 |
皮肤病学 | 40篇 |
神经病学 | 34篇 |
特种医学 | 149篇 |
外国民族医学 | 1篇 |
外科学 | 68篇 |
综合类 | 39篇 |
预防医学 | 79篇 |
眼科学 | 5篇 |
药学 | 45篇 |
中国医学 | 1篇 |
肿瘤学 | 110篇 |
出版年
2022年 | 4篇 |
2021年 | 2篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 10篇 |
2017年 | 13篇 |
2016年 | 13篇 |
2015年 | 29篇 |
2014年 | 18篇 |
2013年 | 33篇 |
2012年 | 25篇 |
2011年 | 34篇 |
2010年 | 34篇 |
2009年 | 49篇 |
2008年 | 29篇 |
2007年 | 27篇 |
2006年 | 20篇 |
2005年 | 24篇 |
2004年 | 34篇 |
2003年 | 19篇 |
2002年 | 14篇 |
2001年 | 13篇 |
2000年 | 12篇 |
1999年 | 20篇 |
1998年 | 54篇 |
1997年 | 63篇 |
1996年 | 56篇 |
1995年 | 42篇 |
1994年 | 41篇 |
1993年 | 38篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 20篇 |
1989年 | 15篇 |
1988年 | 22篇 |
1987年 | 26篇 |
1986年 | 21篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1982年 | 18篇 |
1981年 | 3篇 |
1980年 | 9篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1968年 | 3篇 |
1959年 | 2篇 |
排序方式: 共有1002条查询结果,搜索用时 0 毫秒
91.
Manna R; Todaro L; Latteri M; Gambassi G; Massi G; Grillo MR; Romito A; Caputo S; Gasbarrini GB 《Rheumatology (Oxford, England)》1997,36(1):124-125
The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but
recently hepatitis C virus (HCV) has been suggested as trigger of
autoimmunity. We report a case of a 26-yr-old patient with purpura due to
leucocytoclastic vasculitis associated with hepatitis C virus infection.
Laboratory findings showed AST, ALT, gamma GT within normal limits,
positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction
for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin
antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic
antibodies with perinuclear pattern were also present. A skin biopsy
specimen of a purpuric lesion showed leucocytoclastic vasculitis with small
vessel thrombosis and perivascular deposition of IgM and fibrinogen on
immunofluorescence study. This case shows a role of HCV in leucocytoclastic
vasculitis; it is possible that this HCV can induce autoimmunity
independently of cryoglobulins and liver involvement.
相似文献
92.
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus. 相似文献
93.
G Micali † MR Nasca † R De Pasquale † D Innocenzi‡ 《Journal of the European Academy of Dermatology and Venereology》2003,17(3):320-323
Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis. 相似文献
94.
MR Carvalho ; MA Krieger ; E Almeida ; W Oelemann ; MA Shikanai-Yassuda ; AW Ferreira ; JB Pereira ; A Saez-Alquezar ; PE Dorlhiac-Llacer ; DF Chamone ; et al. 《Transfusion》1993,33(10):830-834
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease. 相似文献
95.
M Alidoosti M Salarifar SE Kassaian AMH Zeinali MS Fathollahi MR Dehkordi 《Cardiovascular journal of Africa》2008,19(6):297-302
Background
Direct stenting without balloon dilatation may reduce procedural costs and duration, and hypothetically, the restenosis rate. This study was designed to compare the in-hospital and long-term outcomes of direct stenting (DS) versus stenting after pre-dilatation (PS) in our routine clinical practice.Methods
The 1 603 patients treated with stenting for single coronary lesions were enrolled into a prospective registry. Patients with acute myocardial infarction (MI) within the preceding 48 hours, and those with highly calcified lesions, total occlusions, or a lesion in a saphenous graft were excluded. The baseline, angiographic and procedural data, inhospital outcomes and follow-up data were recorded in our database and analysed with appropriate statistical methods.Results
Eight hundred and fifty-seven patients (53.5%) were treated with DS and 746 (46.5%) underwent PS. In the DS group, lesions were shorter in length, larger in diameter and had lower pre-procedural diameter stenosis. Type C and diffuse lesions and drug-eluting stents were found less often (p < 0.001). With univariate analysis, dissection and non-Q-wave MI occurred less frequently in this group (0.2 and 0.6% vs 3.9 and 2.1%, p < 0.001 and p = 0.01, respectively). However, the cumulative major adverse cardiac events (MACE) did not differ significantly (4.9 vs 4.6%, p = 0.79). With multivariate analysis, direct stenting reduced the risk of dissection (OR = 0.07, 95% CI: 0.01–0.33, but neither the cumulative endpoint of MACE (OR = 1.1, 95% CI = 0.58–2.11, p = 0.7) nor its constructing components were different between the groups.Conclusions
Direct stenting in the real world has at least similar long-term outcomes in patients treated with stenting after pre-dilatation, and is associated with lower dissection rates. 相似文献96.
97.
Kyle M. Walsh Veryan Codd Terri Rice Christopher P. Nelson Ivan V. Smirnov Lucie S. McCoy Helen M. Hansen Edward Elhauge Juhi Ojha Stephen S. Francis Nils R. Madsen Paige M. Bracci Alexander R. Pico Annette M. Molinaro Tarik Tihan Mitchel S. Berger Susan M. Chang Michael D. Prados Robert B. Jenkins Joseph L. Wiemels ENGAGE Consortium Telomere Group Nilesh J. Samani John K. Wiencke Margaret R. Wrensch 《Oncotarget》2015,6(40):42468-42477
Telomere maintenance has emerged as an important molecular feature with impacts on adult glioma susceptibility and prognosis. Whether longer or shorter leukocyte telomere length (LTL) is associated with glioma risk remains elusive and is often confounded by the effects of age and patient treatment. We sought to determine if genotypically-estimated LTL is associated with glioma risk and if inherited single nucleotide polymorphisms (SNPs) that are associated with LTL are glioma risk factors. Using a Mendelian randomization approach, we assessed differences in genotypically-estimated relative LTL in two independent glioma case-control datasets from the UCSF Adult Glioma Study (652 patients and 3735 controls) and The Cancer Genome Atlas (478 non-overlapping patients and 2559 controls). LTL estimates were based on a weighted linear combination of subject genotype at eight SNPs, previously associated with LTL in the ENGAGE Consortium Telomere Project. Mean estimated LTL was 31bp (5.7%) longer in glioma patients than controls in discovery analyses (P = 7.82×10-8) and 27bp (5.0%) longer in glioma patients than controls in replication analyses (1.48×10-3). Glioma risk increased monotonically with each increasing septile of LTL (O.R.=1.12; P = 3.83×10-12). Four LTL-associated SNPs were significantly associated with glioma risk in pooled analyses, including those in the telomerase component genes TERC (O.R.=1.14; 95% C.I.=1.03-1.28) and TERT (O.R.=1.39; 95% C.I.=1.27-1.52), and those in the CST complex genes OBFC1 (O.R.=1.18; 95% C.I.=1.05-1.33) and CTC1 (O.R.=1.14; 95% C.I.=1.02-1.28). Future work is needed to characterize the role of the CST complex in gliomagenesis and further elucidate the complex balance between ageing, telomere length, and molecular carcinogenesis. 相似文献
98.
99.
100.
Adhesion of sickle neutrophils and erythrocytes to fibronectin 总被引:2,自引:0,他引:2
The pathophysiology of vaso-occlusive crisis in sickle cell disease involves interactions among blood cells, plasma proteins, and vessel wall components. The initial goal of this work was to quantify the adhesion of sickle red blood cells (RBCs) to fibronectin immobilized on glass under both static and dynamic shear stress conditions. High-power microscopic inspection of static assay plates showed striking numbers of adherent neutrophils as well as RBCs. Sickle neutrophils and RBCs were significantly more adherent to fibronectin than the corresponding normal cells in static adhesion assays. Adhesion of both sickle neutrophils and sickle RBCs in dynamic adhesion assays was promoted by a period of static incubation preceding initiation of shear stress conditions. Adherent neutrophils remained attached at shear stresses up to 51 dyne/cm2; most adherent RBCs were attached at shear stresses up to 13 dyne/cm2, but detached at a shear stress of 20 dyne/cm2. Sickle neutrophil adhesion was enhanced significantly by autologous plasma. Elevated levels of plasma interleukin-6 (IL-6; but not IL-1 or IL-8) were found in 6 of 9 sickle cell disease samples examined, and elevated levels of tumor necrosis factor were found in 2 of 9 samples. Plasma IL- 6 levels correlated positively with both the number of sickle neutrophils adherent to fibronectin and the ability of sickle plasma to enhance adhesion of normal neutrophils to fibronectin. These data suggest possible roles for neutrophil activation and for fibronectin in mediating sickle neutrophil and RBC adhesion. 相似文献