全文获取类型
收费全文 | 2592篇 |
免费 | 125篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 45篇 |
儿科学 | 71篇 |
妇产科学 | 64篇 |
基础医学 | 410篇 |
口腔科学 | 255篇 |
临床医学 | 173篇 |
内科学 | 468篇 |
皮肤病学 | 56篇 |
神经病学 | 236篇 |
特种医学 | 28篇 |
外科学 | 206篇 |
综合类 | 8篇 |
一般理论 | 3篇 |
预防医学 | 301篇 |
眼科学 | 52篇 |
药学 | 247篇 |
中国医学 | 32篇 |
肿瘤学 | 72篇 |
出版年
2024年 | 1篇 |
2023年 | 22篇 |
2022年 | 16篇 |
2021年 | 60篇 |
2020年 | 46篇 |
2019年 | 55篇 |
2018年 | 123篇 |
2017年 | 91篇 |
2016年 | 92篇 |
2015年 | 129篇 |
2014年 | 113篇 |
2013年 | 165篇 |
2012年 | 243篇 |
2011年 | 306篇 |
2010年 | 144篇 |
2009年 | 78篇 |
2008年 | 218篇 |
2007年 | 187篇 |
2006年 | 175篇 |
2005年 | 160篇 |
2004年 | 103篇 |
2003年 | 89篇 |
2002年 | 60篇 |
2001年 | 6篇 |
2000年 | 12篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1968年 | 1篇 |
排序方式: 共有2727条查询结果,搜索用时 15 毫秒
91.
Godoi LC Gomes KB Alpoim PN Carvalho Md Lwaleed BA Sant'Ana Dusse LM 《Journal of thrombosis and thrombolysis》2012,34(1):1-6
Preeclampsia (PE) is a multi-system disorder of human pregnancy, whose etiology remains poorly understood. Preeclamptic women are known to have an increased hypercoagulable state that result in excess fibrin deposition in several organs, which compromises their function. Tissue factor (TF) is the main physiological initiator of blood coagulation and its activity is regulated by a specific inhibitor known as Tissue factor pathway inhibitor (TFPI). Based on the important role of TF and TFPI in hemostasis, we hypothesize that their levels may change in the severe PE contributing to exacerbate hypercoagulable state. Some studies have assessed the balance between TF and TFPI in preeclamptic women, but results are inconsistent. Therefore, the aim of this study was to examine these inconsistencies and to assess TF and TFPI plasma levels in three groups of age matched women; pregnant with severe PE (n = 60), normotensive pregnant (n = 50) and normotensive non-pregnant women (n = 50). There was not significantly different among the three groups for TF plasma levels; severe PE women: 338.4 pg/mL (248.1-457.6), normotensive pregnant women: 301.5 pg/mL (216.4-442.9) and normotensive non-pregnant women 393 pg/mL (310.3-522.9). TFPI plasma levels were higher in severe PE comparing to normotensive pregnant women and normotensive non-pregnant women, 115.8 ng/mL (75-149.8); 80.3 ng/mL (59.6-99.7) and 74.5 ng/mL (47.1-98.0), respectively No difference was found between normotensive pregnant women and normotensive non-pregnant women. As for gestational age, a significant difference in TFPI levels was found between severe PE and normotensive pregnant women up to the 33rd week of pregnancy (p = 0.001), and severe PE and non-pregnant women up to the 34th (p = 0.01). In summary, our results indicated that TF plasma levels did not vary in the studied groups, while TFPI plasma levels were significantly increased in severe PE compared to normotensive pregnant and normotensive non-pregnant women. So, our data do not explain the exacerbated hypercoagulability state observed in severe PE. Further studies evaluating genes expression, TF activity and antigen, total and free TFPI and TFPI-2, both in plasma and obstetric tissues, throughout the pregnancy in PE (mild and severe forms) are required. 相似文献
92.
93.
94.
Leal Rato Miguel Nunes Vicente Beatriz da Cunha Maria Ribeiro Marques Tiago Aguiar de Sousa Diana Canhão Patrícia 《Journal of neurovirology》2020,26(5):805-807
Journal of NeuroVirology - Herpes simplex virus 2 (HSV-2) is a very rare cause of central nervous system (CNS) infections. We report a case of a young woman with a left middle cerebral artery (MCA)... 相似文献
95.
Patrícia Machado Rui Pereira Ana Mafalda Rocha Licínio Manco Natércia Fernandes Juliana Miranda Letícia Ribeiro Virgílio E. Do Rosário António Amorim Leonor Gusmão Ana Paula Arez 《British journal of haematology》2010,149(5):775-784
The genetic component of susceptibility to malaria is both complex and multigenic and the better‐known protective polymorphisms are those involving erythrocyte‐specific structural proteins and enzymes. In vivo and in vitro data have suggested that pyruvate kinase deficiency, which causes a nonspherocytic haemolytic anaemia, could be protective against malaria severity in humans, but this hypothesis remains to be tested. In the present study, we conducted a combined analysis of Short Tandem Repeats (STRs) and Single Nucleotide Polymorphisms (SNPs) in the pyruvate kinase‐encoding gene (PKLR) and adjacent regions (chromosome 1q21) to look for malaria selective signatures in two sub‐Saharan African populations from Angola and Mozambique, in several groups with different malaria infection outcome. A European population from Portugal, including a control and a pyruvate kinase‐deficient group, was used for comparison. Data from STR and SNP loci spread along the PKLR gene region showed a considerably higher differentiation between African and Portuguese populations than that usually found for neutral markers. In addition, a wider region showing strong linkage disequilibrium was found in an uncomplicated malaria group, and a haplotype was found to be associated with this clinical group. Altogether, this data suggests that malaria selective pressure is acting in this genomic region. 相似文献
96.
Patrício Aguiar Diogo Cruz Rita Ferro Rodrigues Lígia Peixoto Francisco Araújo José Luís Ducla Soares 《Revista portuguesa de cardiologia》2013,32(4):331-335
The association between hypocalcemia and heart failure is rare. There are few reported cases in the literature of this association, which is termed hypocalcemic cardiomyopathy.We report the case of a 61-year-old woman with no relevant medical history, admitted for progressively worsening exertional dyspnea, orthopnea and edema of the lower limbs for a previous month. Physical examination showed diffuse muscle spasms, with no signs of latent tetany.Further investigation revealed ionized calcium 0.54 mmol/l (normal 1.12-1.30), phosphorus 9.8 mg/dl, parathyroid hormone <2.5 pg/ml and CK >3000 U/l, with normal thyroid function. The electrocardiogram showed long QT interval and a pattern of left ventricular overload, and myocardial biomarkers were negative. The echocardiogram revealed regional wall motion abnormalities, coronary angiography was normal and a cranial CT scan detected calcification of basal ganglia and white matter.She started diuretic and calcium replacement therapy which resulted in complete clinical recovery, with no need for heart failure therapy after normalization of serum calcium. 相似文献
97.
Caroline Xavier-Carvalho Renata Duarte da Silva Cezar Naishe Matos Freire Carla Maria Mola de Vasconcelos Victor Edgar Fiestas Solorzano Thiago Gomes de Toledo-Pinto Luciana Gomes Fialho Rodrigo Feliciano do Carmo Luydson Richardson Silva Vasconcelos Marli Tenório Cordeiro Paulo Baptista Elzinandes leal de Azeredo Rivaldo Venâncio da Cunha Luiz José de Souza Antonio Guilherme Pacheco Claire Fernandes Kubelka Patrícia Muniz Mendes Freire de Moura Milton Ozorio Moraes 《Human immunology》2017,78(10):649-656
Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors. 相似文献
98.
99.
100.
Gomes PB Noronha EC de Melo CT Bezerra JN Neto MA Lino CS Vasconcelos SM Viana GS de Sousa FC 《Journal of ethnopharmacology》2008,120(2):209-214