全文获取类型
收费全文 | 311篇 |
免费 | 8篇 |
专业分类
耳鼻咽喉 | 73篇 |
妇产科学 | 4篇 |
基础医学 | 20篇 |
口腔科学 | 4篇 |
临床医学 | 12篇 |
内科学 | 34篇 |
皮肤病学 | 6篇 |
神经病学 | 45篇 |
特种医学 | 39篇 |
外科学 | 19篇 |
预防医学 | 9篇 |
药学 | 40篇 |
中国医学 | 6篇 |
肿瘤学 | 8篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 4篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2015年 | 14篇 |
2014年 | 9篇 |
2013年 | 17篇 |
2012年 | 24篇 |
2011年 | 16篇 |
2010年 | 14篇 |
2009年 | 7篇 |
2008年 | 16篇 |
2007年 | 10篇 |
2006年 | 7篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 2篇 |
2001年 | 12篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1976年 | 1篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 1篇 |
1970年 | 3篇 |
1969年 | 4篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有319条查询结果,搜索用时 15 毫秒
1.
2.
Quantitative structure-activity relationships (QSAR) have been derived for twenty two 5-benzylidene furanones, pyrrolones and thiophenones having antifungal activity against Candida albicans. The correlation with the parabolic (Hansch) or bilinear (McFarland-Kubinyi) models are superior to those with the linear models (Free-Wilson or Fujita-Ban), while no significant differences exist between the parabolic and bilinear models. Lipophilicity was necessary for good in vitro activity of these compounds. 相似文献
3.
Acute otomastoiditis and its complications: role of CT 总被引:2,自引:0,他引:2
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess. 相似文献
4.
Soraya Castro Trindade Teresa Olczak Isaac Suzart Gomes‐Filho Lília Ferreira de Moura‐Costa Vera Costa Vale Milton Galdino‐Neto Heidiane Alves dos Santos Paulo Cirino de Carvalho Filho Andreas Stocker Maria Teresita Bendicho Márcia Tosta Xavier Eneida de Moraes Marcílio Cerqueira Roberto Meyer 《Journal of periodontology》2013,84(5):650-655
Background: In chronic periodontitis (CP), the gene polymorphism of interleukin‐6 (IL‐6) to 174C/G has been associated with the altered production of this cytokine. The aim of this pilot study is to compare the allelic and genotypic frequencies in patients with CP with control individuals without periodontitis (NP) and to measure the production of IL‐6 by whole blood cells stimulated with Porphyromonas gingivalis HmuY protein. Methods: DNA was isolated from peripheral blood cells of 49 patients with CP and 60 control individuals classified as NP, and genotyping was performed by polymerase chain reaction using sequence‐specific primers. Whole blood cells from 29 patients with CP and 30 control individuals were stimulated for 48 hours with HmuY, and IL‐6 levels were measured using enzyme‐linked immunosorbent assay. Results: The proportion of individuals carrying the G allele at position –174 of the IL‐6 gene was higher in the group with CP (85.7%) than in the normal control group (73.3%; P <0.03). P. gingivalis HmuY‐induced production of IL‐6 was higher in the group with CP (P <0.05). Conclusions: Our findings suggest that P. gingivalis HmuY may be associated with increased IL‐6 production during CP. Furthermore, patients with periodontitis and individuals with higher HmuY‐induced production of IL‐6 show a high frequency of the G allele at position –174. 相似文献
5.
Castelo B. Vilanculo Mrcio J. Da Silva Milena Galdino Teixeira Jesus Avendano Villarreal 《RSC advances》2020,10(13):7691
In this work, we describe a new one-pot synthesis route of valuable linalool oxidation derivatives (i.e., 2-(5-methyl-5-vinyltetrahydrofuran-2-yl propan-2-ol) (1a)), 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (1b) and diepoxide (1c), using a green oxidant (i.e., hydrogen peroxide) under mild conditions (i.e., room temperature). Lacunar Keggin heteropolyacid salts were the catalysts investigated in this reaction. Among them, Na7PW11O39 was the most active and selective toward oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD analyses and potentiometric titration. The main reaction parameters were assessed. Special attention was dedicated to correlating the composition and properties of the catalysts and their activity.In this work, the catalyst Na7PW11O39 was used in a new one-pot synthesis route to oxidize linalool to valuable derivatives (i.e., vinyltetrahydrofuran, vinyltetrahydropyran, and diepoxide), using a green oxidant (H2O2) at room temperature. 相似文献
6.
Roger B. Varela Samira S. Valvassori Jéssica Lopes-Borges Daiane B. Fraga Wilson R. Resende Camila O. Arent Alexandra I. Zugno João Quevedo 《Psychiatry research》2013
The present study aims to investigate the effects of mood stabilizers, lithium (Li) and valproate (VPA), on acetylcholinesterase (AChE) activity in the brains of rats subjected to an animal model of mania induced by d-amphetamine (d-AMPH). In the reversal treatment, Wistar rats were first given d-AMPH or saline (Sal) for 14 days. Between days 8 and 14, the rats were treated with Li, VPA, or Sal. In the prevention treatment, rats were pretreated with Li, VPA, or Sal. AChE activity was measured in the brain structures (prefrontal cortex, hippocampus, and striatum). Li, alone in reversion and prevention treatments, increased AChE activity in the brains of rats. VPA, alone in prevention treatment, increased AChE activity in all brain regions evaluated; in the reversion, only in the prefrontal. However, d-AMPH decreased activity of AChE in the striatum of rats in both the reversion and prevention treatments. VPA was able to revert and prevent this AChE activity alteration in the rat striatum. Our findings further support the notion that the mechanisms of mood stabilizers also involve changes in AChE activity, thus reinforcing the need for more studies to better characterize the role of acetylcholine in bipolar disorder. 相似文献
7.
Barichello T Machado RA Constantino L Valvassori SS Réus GZ Martins MR Petronilho F Ritter C Quevedo J Dal-Pizzol F 《Critical care medicine》2007,35(9):2186-2190
OBJECTIVE: Assess the effect of antioxidant treatment on late memory impairment and early hippocampus oxidative stress after cecal ligation and perforation. SUBJECTS: Male Wistar rats. INTERVENTIONS: Rats underwent sham operation or cecal ligation and perforation. Animals that underwent cecal ligation and perforation were divided into groups: 1) treated with basic support (50 mL/kg saline, 30 mg/kg ceftriaxone, and 25 mg/kg clindamycin every 6 hrs), 2) treated with basic support plus N-acetylcysteine (20 mg/kg N-acetylcysteine at 3, 6, 12, 18, and 24 hrs after cecal ligation and perforation), 3) treated with basic support plus deferoxamine (20 mg/kg deferoxamine at 3 and 24 hrs after cecal ligation and perforation), 4) treated with basic support plus N-acetylcysteine and deferoxamine, or 5) treated with N-acetylcysteine plus deferoxamine. MEASUREMENTS AND MAIN RESULTS: On days 10 and 30 after surgery, the animals underwent behavioral tasks: inhibitory avoidance task, habituation to an open field, and continuous multiple-trials step-down inhibitory avoidance task. The sepsis group showed significantly decreased performance in latency retention compared with the sham group in the inhibitory avoidance task. In the open-field task, the sepsis group presented memory impairment after sepsis. In the continuous multiple-trials step-down inhibitory avoidance task, the sepsis group showed a significant increase in the number of training trials required to reach the acquisition criterion. All these memory impairments were prevented by N-acetylcysteine plus deferoxamine treatment, but not its isolate use. In addition, the combined use of antioxidants attenuated oxidative damage in hippocampus 6 hrs after sepsis induction. CONCLUSIONS: Antioxidant treatment prevented the development of late cognitive deficits in an animal model of sepsis. 相似文献
8.
Samira S. Valvassori Daniela V. Bavaresco Josiane Budni Tamara S. Bobsin Cinara L. Gonçalves Karolina V. de Freitas Emilio L. Streck João Quevedo 《Psychiatry research》2014
The neurobiological basis of bipolar disorder (BD) remains unknown; nevertheless, mitochondrial dysfunction has been identified in this disorder. Inactivation of any step in the tricarboxylic acid (TCA) cycle can impair mitochondrial ATP production. There is recent evidence indicating that PKC is an important therapeutic target for bipolar disorder. Therefore, we evaluated the effects of tamoxifen (TMX—a PKC inhibitor) on the activities of enzymes in the TCA cycle of rat brains subjected to an animal model of mania induced by amphetamine. In the reversal treatment, Wistar rats were first treated with d-AMPH or saliratsne (Sal) for 14 days. Thereafter, between days 8 and 14, the rats were administered TMX or Sal. The citrate synthase, succinate dehydrogenase, and malate dehydrogenase were evaluated in the frontal cortex, hippocampus, and striatum. The d-AMPH administration inhibited TCA cycle enzymes activity in all analyzed structures, and TMX reversed d-AMPH-induced dysfunction. In addition, we observed a negative correlation between d-AMPH-induced hyperactivity and the activity of these enzymes in the rat's brain. These findings suggested that TCA cycle enzymes inhibition can be an important link for the mitochondrial dysfunction seen in BD, and TMX exert protective effects against the d-AMPH-induced TCA cycle enzymes dysfunction. 相似文献
9.
Juliana Cruz da Silva Henrique Ataide Mariz Laurindo Ferreira da Rocha Júnior Priscilla Stela Santana de Oliveira Andrea Tavares Dantas Angela Luzia Branco Pinto Duarte Ivan da Rocha Pitta Suely Lins Galdino Maira Galdino da Rocha Pitta 《Clinics (S?o Paulo, Brazil)》2013,68(6):766-771
OBJECTIVES:
Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients.METHODS:
Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients.RESULTS:
We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine.CONCLUSIONS
Our in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication. 相似文献10.
Amanda Karolina Soares e Silva Dilênia de Oliveira Cipriano Torres Sura Wanessa Santos Rocha Fabiana Oliveira dos Santos Gomes Bruna dos Santos Silva Mariana Aragão Matos Donato Catarina Raposo Ana Célia Oliveira Santos Maria do Carmo Alves de Lima Suely Lins Galdino Ivan da Rocha Pitta José Roberto Botelho de Souza Christina Alves Peixoto 《Cardiovascular pathology》2013,22(1):81-90
BackgroundAtherosclerotic cardiovascular disease is a chronic inflammatory condition. Thiazolidinediones (TZDs) are used to enhance sensitivity to insulin and have demonstrated a protective effect over a variety of cardiovascular markers and risk factors. Controversially, the TZDs are associated with the development of heart failure. Thus, lines of research have invested in the search for new molecules in order to obtain more selective and less harmful treatment alternatives for the pathogenesis of atherosclerosis and its risk factors.MethodsAnimals were fed a diet rich in fat for 10 weeks. In the last 2 weeks, animals received either pioglitazone, LPSF/GQ-02, or LPSF/GQ-16 daily through gavage. At the end of the treatment, blood was collected for biochemical analysis and the aortas were dissected for subsequent analyses.ResultsNo changes in the blood lipid profile were found following the use of the drugs in comparison to the control. However, the new thiazolidine derivatives were more efficient in improving insulin resistance in comparison to pioglitazone and the control group. Morphometric analyses revealed that neither pioglitazone nor LPSF/GQ16 led to satisfactory effects over atherosclerosis. However, LPSF/GQ-02 led to a reduction in area of the atherosclerotic lesions. Ultrastructural analyses revealed extensive degeneration of the endothelium and an increase in apoptotic cells in the subendothelial space following the use of pioglitazone and LPSF/GQ-16. However, LPSF/GQ-02 caused minimal cell alterations in the aortic endothelium. Regarding markers, endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase 9 (MMP-9), LPSF/GQ-16, and pioglitazone exerted similar effects, increasing the expression of MMP-9, and had no effect on the expression of eNOS compared with the control group. On the other hand, LPSF/GQ-02 was effective in reducing the expression of MMP-9 and increased eNOS significantly.ConclusionsThe results suggest that the new thiazolidine derivative LPSF/GQ-02 is a promising candidate for the treatment of atherosclerosis. 相似文献