全文获取类型
收费全文 | 6215篇 |
免费 | 387篇 |
国内免费 | 56篇 |
专业分类
耳鼻咽喉 | 61篇 |
儿科学 | 159篇 |
妇产科学 | 94篇 |
基础医学 | 1073篇 |
口腔科学 | 348篇 |
临床医学 | 467篇 |
内科学 | 1433篇 |
皮肤病学 | 189篇 |
神经病学 | 548篇 |
特种医学 | 116篇 |
外科学 | 560篇 |
综合类 | 46篇 |
一般理论 | 2篇 |
预防医学 | 516篇 |
眼科学 | 112篇 |
药学 | 459篇 |
中国医学 | 49篇 |
肿瘤学 | 426篇 |
出版年
2024年 | 8篇 |
2023年 | 114篇 |
2022年 | 225篇 |
2021年 | 353篇 |
2020年 | 204篇 |
2019年 | 280篇 |
2018年 | 272篇 |
2017年 | 187篇 |
2016年 | 259篇 |
2015年 | 249篇 |
2014年 | 288篇 |
2013年 | 356篇 |
2012年 | 544篇 |
2011年 | 573篇 |
2010年 | 279篇 |
2009年 | 213篇 |
2008年 | 370篇 |
2007年 | 343篇 |
2006年 | 307篇 |
2005年 | 315篇 |
2004年 | 250篇 |
2003年 | 243篇 |
2002年 | 191篇 |
2001年 | 22篇 |
2000年 | 20篇 |
1999年 | 22篇 |
1998年 | 48篇 |
1997年 | 25篇 |
1996年 | 14篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
排序方式: 共有6658条查询结果,搜索用时 15 毫秒
991.
992.
Gabriela da Silva Cruz Ana Luiza Dias Angelo Ticiana Ferreira Larocca Carolina Thé Macedo Márcia Noya- Rabelo Luís Claudio Lemos Correia Jorge Andion Torre?o Bruno Solano de Freitas Souza Ricardo Ribeiro dos Santos Milena Botelho Pereira Soares 《Arquivos brasileiros de cardiologia》2015,105(5):472-478
Background
Galectin-3, a β-galactoside binding lectin, has been described as a mediator of cardiac fibrosis in experimental studies and as a risk factor associated with cardiovascular events in subjects with heart failure. Previous studies have evaluated the genetic susceptibility to Chagas disease in humans, including the polymorphisms of cytokine genes, demonstrating correlations between the genetic polymorphism and cardiomyopathy development in the chronic phase. However, the relationship between the galectin-3 single nucleotide polymorphism (SNP) and phenotypic variations in Chagas disease has not been evaluated.Objective
The present study aimed to determine whether genetic polymorphisms of galectin-3 may predispose to the development of cardiac forms of Chagas disease.Methods
Fifty-five subjects with Chagas disease were enrolled in this observational study. Real-time polymerase chain reaction (PCR) was used for genotyping the variants rs4644 and rs4652 of the galectin-3 gene.Results
For the SNP rs4644, the relative risk for the cardiac form was not associated with the genotypes AA (OR = 0.79, p = 0.759), AC (OR = 4.38, p = 0.058), or CC (OR = 0.39, p = 0.127). Similarly, for the SNP rs4652, no association was found between the genotypes AA (OR = 0.64, p = 0.571), AC (OR = 2.85, p = 0.105), or CC (OR = 0.49, p = 0.227) and the cardiac form of the disease.Conclusion
Our results showed no association between the different genotypes for both SNPs of the galectin-3 gene and the cardiac form of Chagas disease. 相似文献993.
Combination of Controlled Release Platelet‐Rich Plasma Alginate Beads and Bone Morphogenetic Protein‐2 Genetically Modified Mesenchymal Stem Cells for Bone Regeneration 下载免费PDF全文
Gabriela Fernandes Changdong Wang Xue Yuan Zunpeng Liu Rosemary Dziak Shuying Yang 《Journal of periodontology》2016,87(4):470-480
Background: Platelet‐rich plasma (PRP) consists of platelet‐derived growth factor and transforming growth factor‐β that increase proliferation of mesenchymal stem cells (MSCs), whereas bone morphogenetic protein‐2 (BMP2) promotes osteogenic differentiation of MSCs. However, the high degradation rate of fibrin leads to the dissociation of cytokines even before the process of bone regeneration begins. To the best of the authors’ knowledge, this is the first study to examine the combined effect of sustained release of PRP from alginate beads on BMP2‐modified MSC osteogenic differentiation in vitro and sustained release of PRP alone on a fracture defect model ex vivo as well as its effect on calvarial suture closure. Methods: After optimizing the alginate concentration for microspheres, the combined osteogenic and mineralization effect of PRP and BMP2 on MSCs was studied. Self‐setting alginate hydrogel carrying PRP was tested on a femur defect model ex vivo. The effect of PRP at day 15 on the closure of the embryonic mouse calvaria sutures ex vivo was also studied. Results: Increase of PRP concentration promoted proliferation of MSCs, and 2.5% to 10% of PRP gradually increased alkaline phosphatase (ALP) activity in the cells in a dose‐dependent manner. Sustained release of PRP and BMP2 demonstrated significantly higher ALP and mineralization activity (P <0.05). Radiographs of alginate hydrogel with PRP‐treated bone demonstrated nearly complete healing of the fracture, and histologic sections of the embryonic calvaria revealed that PRP leads to suture fusion. Conclusion: Sustained release of PRP along with BMP2‐modified MSCs can significantly promote bone regeneration. 相似文献
994.
Priccila Zuchinali Gabriela C. Souza Graziella Aliti Mariana R. Botton Lívia Goldraich Katia G. Santos Mara H. Hutz Eliane Bandinelli Luis E. Rohde 《Journal of thrombosis and thrombolysis》2014,37(3):338-344
Significant inter-individual variability on the effect of vitamin K to reverse overanticoagulation has been identified. Genetic polymorphisms of the vitamin K epoxide reductase complex subunit 1 (VKORC1) gene might explain in part this variability. The objective of this study was to evaluate the influence of VKORC1 ?1639G>A and 3730G>A polymorphisms on the effect of oral vitamin K supplementation in overanticoagulated patients. We performed an interventional trial of oral vitamin K supplementation in over-anticoagulated outpatients (international normalized ratio [INR] ≥ 4). Subjects received vitamin K (2.5–5.0 mg) according to baseline INR and were genotyped by real time polymerase chain reaction (PCR). INR values were determined at 3, 6, 24 and 72 h after supplementation. We evaluated 33 outpatients, 61 % were males, with a mean age of 62 ± 12 years old. There was a significant decrease in INR values over time for both polymorphisms after oral vitamin K. At 3 h after supplementation, patients carrying the G allele for the ?1639G>A polymorphism had a greater decrease in INR values compared to AA patients (p < 0.05 for difference among groups; p < 0.001 for time variation; p = 0.001 for time × group interaction), with differences of ?1.01 for GG versus AA (p = 0.003) and ?0.84 for GA versus AA (p = 0.024). Mean INR value at 24 h was 1.9 ± 0.6 and at 72 h was 2.1 ± 0.7, with no differences among genotypes. No significant interaction was identified between the 3730G>A polymorphism and vitamin K supplementation. Our study indicated that the VKORC1 ?1639G>A polymorphism plays a role in the response to acute vitamin K supplementation in over-anticoagulated patients, with faster decrease of INR value in patients carrying the G allele. 相似文献
995.
de Oliveira Ribeiro Rafael Antonio Zuta Uxua Ortecho Soares Igor Paulino Mendes Anselmi Caroline Soares Diana Gabriela Briso André Luiz Fraga Hebling Josimeri de Souza Costa Carlos Alberto 《Clinical oral investigations》2022,26(12):7277-7286
Clinical Oral Investigations - The study aims to assess the effects of a 10% H2O2 bleaching gel with different MnO2 concentrations on the bleaching efficacy (BE), degradation kinetics (DK) of H2O2,... 相似文献
996.
Barros Antonia Patricia Oliveira de Melo Alencar Cristiane de Melo Pingarilho Carneiro Alexandra da Silva Pompeu Danielle Barbosa Gabriela Monteiro Araújo Jesuína Lamartine Nogueira Silva Cecy Martins 《Clinical oral investigations》2022,26(2):1299-1307
Clinical Oral Investigations - This study evaluated the effect of photobiomodulation (PBM) combined with 8% strontium acetate (SA8%) in the treatment of dentin hypersensitivity (DH) in non-carious... 相似文献
997.
Falcão Gleicy Gabriela Vitória Spínola Carneiro Sarmento Viviane Almeida Dutra Brenda Soares Russoni Bruno de Oliveira Letycia Santos Costa Dayana Alves Brites Carlos Bouqout Jerry E. Lins-Kusterer Liliane 《Clinical oral investigations》2022,26(3):2565-2573
Clinical Oral Investigations - To compare the oral health status and oral health-related quality of life (OHRQoL) in symptomatic and asymptomatic patients with human T-cell leukemia virus-1... 相似文献
998.
Investigate the presence of Lactobacillus reuteri in saliva after supplementation with L. reuteri and the probiotic effect of L. reuteri on plaque index and supra- and subgingival microbiota. MATERIAL AND METHODS: The study included 23 healthy individuals, randomised into test or control subjects. At baseline and after 12 weeks saliva samples, plaque index and supra- and subgingival plaque samples were obtained. The test subjects were given the study product (containing L. reuteri, ATCC 55730 and ATCC PTA 5289) and the control subjects placebo for 12 weeks. Microbiological analyses were done by checkerboard DNA-DNA hybridization technique and selective culturing for lactobacilli determination. RESULTS: A significant increase in total Lactobacillus counts in saliva occurred in both groups (p < 0.05) with a significant increase of L. reuteri (p = 0.008) in the test group.Termination of intervention resulted in a wash out of L. reuteri. The control group demonstrated a statistically significant increase in PII after 12 weeks (p = 0.023) whilst there was no significant change in the test group. A significant increase was found for most bacterial species in both groups in supra- and subgingival plaque with no significant difference for any of the species between the groups. The ratio between "bad/good" supragingival bacteria decreased for the test group but this decrease did not reach significance. The corresponding ratio for subgingival bacteria decreased significantly in both groups. Supplementation of L. reuteri resulted in presence of L. reuteri in saliva but L. reuteri was washed out after termination of intervention. No significant effect on supra- or subgingival microbiota was observed. The significant increase in PII in the control group with no significant change in the test group may, however, indicate a probiotic effect of L. reuteri in this study population. 相似文献
999.
1000.
Olivera Grbovic-Huezo Kenneth L. Pitter Nicolas Lecomte Joseph Saglimbeni Gokce Askan Matilda Holm Jerry P. Melchor Rohit Chandwani Suhasini Joshi Caj Haglund Christine A. Iacobuzio-Donahue Gabriela Chiosis Tuomas Tammela Steven D. Leach 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(48):30670