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211.
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Ferdinando Iellamo Vincenzo Manzi Giuseppe Caminiti Cristiana Vitale Carlo Castagna Michele Massaro Alessio Franchini Giuseppe Rosano Maurizio Volterrani 《International journal of cardiology》2013
Background
The best format of exercise training in patients with chronic heart failure (CHF) is controversial. We tested the hypothesis that aerobic continuous training (ACT) and aerobic interval training (AIT) induce similar effects on functional capacity, central hemodynamics and metabolic profile in patients with postinfarction CHF provided that the training load is equated by an individually-tailored volume/intensity dose of exercise.Methods
Twenty patients with postinfarction CHF under optimal medical treatment were randomized to ACT or AIT for 12 weeks. Exercise training consisted in individualized loads prescribed according to the Training Impulses (TRIMPi) method, which was determined using the individual HR and lactate profiling obtained during a treadmill test at baseline.Results
Peak VO2 increased significantly by 22% with both ACT and AIT, without differences between the two training programs. Changes in anaerobic threshold and VE/VCO2 slope were not significantly different between ACT and AIT. Resting HR significantly decreased with both exercise modes. Resting cardiac output and stroke volume, left ventricular diastolic dimension and ejection fraction did not change from baseline with both exercise modes. Lipid profile and glucose metabolism were not substantially altered by ACT and AIT.Conclusions
ACT and AIT both induce significant improvement in aerobic capacity in patients with postinfarction CHF, without significant differences between the two training modes, provided that patients are trained at the same, individually tailored, dose of exercise. The TRIMPi method might represent a step forward in the individualization of an aerobic training tailored to the patient's clinical and functional status within cardiac rehabilitation programs. 相似文献213.
Matache C Stefanescu M Dragomir C Tanaseanu S Onu A Ofiteru A Szegli G 《Journal of autoimmunity》2003,20(4):323-331
Matrix metalloproteinase-9 (MMP-9) was involved in inflammation and immune system dysfunctions. Besides immunologic abnormalities, systemic lupus erythematosus (SLE) also presents chronic inflammatory components. Therefore, a role of MMP-9 in SLE pathology might be supposed. To verify this hypothesis, SLE patients and healthy donors were compared for the MMP-9 and MMP-9 mRNA levels in peripheral blood mononuclear cells (PBMCs), the spontaneous secretion of MMP-9 and TIMP-1 and the MMP-9 activity. Thus, we found that fresh PBMCs from SLE patients expressed a significantly higher activity of MMP-9 and spontaneously released higher levels of MMP-9, as compared to healthy donors, while the secreted TIMP-1 level was the same for both groups. When the patients were sub-grouped based on disease status, the most increased pro-MMP-9 activity inside the PBMCs was identified for relapse SLE sub-group. A similar observation for SLE patients with positive serum fibrinogen was found. Following culture, the PBMCs from remission SLE patients secreted significantly higher MMP-9 level, than the PBMCs from relapse SLE patients. PBMCs from relapse SLE patients secreted the highest levels of TIMP-1, although this difference was not statistically significant. Taken together, these observations suggested the multiple roles of MMP-9 and TIMP-1 in progress of inflammation and tissue damage and/or in repair, depending on clinical stages of SLE. 相似文献
214.
Gambacciani M Monteleone P Vitale C Silvestri A Fini M Genazzani AR Rosano GM 《Maturitas》2002,43(2):117-123
OBJECTIVES: The purpose of this study was to evaluate endothelium-dependent flow-mediated dilation (FMD) in the brachial artery and the plasma levels of endothelin-1 in postmenopausal women at risk for coronary artery disease before and after treatment with both estradiol and estradiol plus dydrogesterone. METHODS: Sixteen postmenopausal women (PMW) (mean age 58+/-9 years) with more than two risk factors for coronary artery disease, were randomized to receive either oral estradiol (2 mg) for 28 days or oral estradiol (2 mg) for 14 days and oral estradiol (2 mg) and dydrogesterone (10 mg) for 14 days, in a double-blind, placebo-controlled, single cross-over study. Patients were crossed-over the complementary treatment 7 days after completing the first treatment. The study of forearm blood flow and the measurement of plasma endothelin-1 levels was carried out before and after each treatment. RESULTS: Estradiol significantly increased FMD as compared to baseline; the addition of dydrogesterone did not affect the effect of estradiol on FMD. Similarly reactive hyperemic flow increased after estradiol alone or in association with dydrogesterone compared to baseline. Plasma levels of endothelin-1 were significantly reduced by estradiol both when administered alone or in association with dydrogesterone. CONCLUSIONS: Hormone replacement therapy with estradiol and dydrogesterone improves endothelial function and reduces plasma levels of endothelin-1 in PMW at risk for coronary artery disease. 相似文献
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Sónia Fraga Helena Faria Maria Elisa Soares José Alberto Duarte Leonor Soares Eulália Pereira Cristiana Costa‐Pereira João Paulo Teixeira Maria de Lourdes Bastos Helena Carmo 《Journal of applied toxicology : JAT》2013,33(10):1111-1119
The toxicological profile of gold nanoparticles (AuNPs) remains controversial. Significant efforts to develop surface coatings to improve biocompatibility have been carried out. In vivo biodistribution studies have shown that the liver is a target for AuNPs accumulation. Therefore, we investigated the effects induced by ~20 nm spherical AuNPs (0–200 μM Au) with two surface coatings, citrate (Cit) compared with 11‐mercaptoundecanoic acid (11‐MUA), in human liver HepG2 cells. Cytotoxicity was evaluated using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) reduction and lactate dehydrogenase (LDH) release assays after 24 to 72 h of incubation. DNA damage was assessed by the comet assay, 24 h after incubation with the capped AuNPs. Uptake and subcellular distribution of the tested AuNPs was evaluated by quantifying the gold intracellular content by graphite furnace atomic absorption spectrometry (GFAAS) and transmission electron microscopy (TEM), respectively. The obtained results indicate that both differently coated AuNPs did not induce significant cytotoxicity. An inverse concentration‐dependent increase in comet tail intensity and tail moment was observed in Cit‐AuNPs‐ but not in MUA‐AuNPs‐exposed cells. Both AuNPs were internalized in a concentration‐dependent manner. However, no differences were found in the extent of the internalization between the two types of NPs. Electron‐dense deposits of agglomerates of Cit‐ and MUA‐AuNPs were observed either inside endosomes or in the intercellular spaces. In spite of the absence of cytotoxicity, DNA damage was observed after exposure to the lower concentrations of Cit‐ but not to MUA‐AuNPs. Thus, our data supports the importance of the surface properties to increase the biocompatibility and safety of AuNPs. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
218.
Anna Paola T. R. Pierucci Leonardo R. Andrade Marco Farina Cristiana Pedrosa Maria Helena M. Rocha-Leão 《Journal of microencapsulation》2013,30(3):201-213
α-Tocopherol is a radical chain breaking antioxidant that can protect the integrity of tissues and play an important role in life process. Microparticles containing α-tocopherol were produced by spray drying technique using pea protein (PP), carboxymethylcellulose(CMC) and mixtures of these materials with maltodextrin (PP-M and CMC-M) as wall materials. The microparticles produced were characterised as regards the core retention (high performance liquid chromatography), the morphology (scanning electron microscopy) and size distribution (laser diffraction). The retention of α-tocopherol within all microparticles was above 77%. They showed a spherical shape and roughness at varied degrees. Their mean particles size remained below 7?µm, and the smallest sizes were found in PP and CMC-M microparticles. The results obtained in this work show that the pea protein use for α-tocopherol microencapsulation is a promising system for further application in food. 相似文献
219.
Anna?Luzzi Federica?Morettini Sara?Gazaneo Lucia?Mundo Anna?Onnis Susanna?Mannucci Emily?A?Rogena Cristiana?Bellan Lorenzo?Leoncini Giulia?De FalcoEmail author 《Infectious agents and cancer》2014,9(1):41
Background
A close association between HIV infection and the development of cancer exists. Although the advent of highly active antiretroviral therapy has changed the epidemiology of AIDS-associated malignancies, a better understanding on how HIV can induce malignant transformation will help the development of novel therapeutic agents.Methods
HIV has been reported to induce the expression of DNMT1 in vitro, but still no information is available about the mechanisms regulating DNMT expression in HIV-related B-cell lymphomas.In this paper, we investigated the expression of DNMT family members (DNMT1, DNMT3a/b) in primary cases of aggressive B-cell lymphomas of HIV-positive subjects.Results
Our results confirmed the activation of DNMT1 by HIV in vivo, and reported for the first time a marked up-regulation of DNMT3a and DNMT3b in HIV-positive aggressive B-cell lymphomas. DNMT up-regulation in HIV-positive tumors correlated with down-regulation of specific microRNAs, as the miR29 family, the miR148-152 cluster, known to regulate their expression. Literature reports the activation of DNMTs by the human polyomavirus BKV large T-antigen and adenovirus E1a, through the pRb/E2F pathway. We have previously demonstrated that the HIV Tat protein is able to bind to the pocket proteins and to inactivate their oncosuppressive properties, resulting in uncontrolled cell proliferation. Therefore, we focused on the role of Tat, due to its capability to be released from infected cells and to dysregulate uninfected ones, using an in vitro model in which Tat was ectopically expressed in B-cells.Conclusions
Our findings demonstrated that the ectopic expression of Tat was per se sufficient to determine DNMT up-regulation, based on microRNA down-regulation, and that this results in aberrant hypermethylation of target genes and microRNAs.These results point at a direct role for Tat in participating in uninfected B-cell lymphomagenesis, through dysregulation of the epigenetical control of gene expression.220.
Anna Sapino Francesca Maletta Ludovica Verdun di Cantogno Luigia Macrì Cristina Botta Patrizia Gugliotta Maria Stella Scalzo Laura Annaratone Davide Balmativola Francesca Pietribiasi Paolo Bernardi Riccardo Arisio Laura Viberti Stefano Guzzetti Renzo Orlassino Cristiana Ercolani Marcella Mottolese Giuseppe Viale Caterina Marchiò 《The oncologist》2014,19(11):1118-1126