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101.
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Background: Due to the possible biomedical potential of nanoparticles, titanium dioxide nanoparticles (TiO2 NPs)have received great attention in cancer research. Although selectivity of cytotoxicity with TiO2 NPs in various cells isclinically significant comparisons of cancer and non-cancer cells have been limited. Therefore, we here studied exposureto TiO2 NPs in colorectal cancer cells (CRCs) and human umbilical vein endothelial cells (HUVECs). Methods: Aftercharacterization of TiO2 NPs, culture and treatment of cells (HCT116, HT29 and HUVEC), viability was assessed byMTT assay and in terms of morphological features. Acridine orange (AO) and propidium iodide (PI) assays were carriedout to estimate the incidence of apoptosis. The RT-PCR method was also employed to evaluate the expression of P53,Bax, Bcl-2 and Caspase 3. Results: Exposure to increasing concentrations of TiO2 NPs enhanced overall cell survivalof HCT116 cells and reduced the Bcl-2 and Caspase 3 expression while the ratio of Bax/Bcl-2 was down-regulated.TiO2 NPs at 400 and 50 μg/ml concentrations suppressed cell proliferation and induced apoptosis of HT29 cells andalso up-regulated P53 and Bax at the mRNA level, enhanced the Bax/Bcl-2 ratio and eventually up-regulated Caspase3 mRNA. Although, inhibition of cell proliferation in HUVECs was seen at 200 and 400 μg/ml TiO2 NPs, it was notmarked. Conclusion: TiO2 NPs have selective bio-effects on exposed cells with dose- and cell-dependent influence onviability. Cell proliferation in HCT116 as a metastatic colorectal cancer cell line appeared to be stimulated via multiplesignaling pathways, with promotion of apoptosis in less metastatic cells at 50 and 400 μg/ml concentrations. This wasassociated with elevated P53, Bax and Caspase 3 mRNA and reduced Bcl-2 expression. However, TiO2 NPs did notexert any apparent significant effects on HUVECs as hyperproliferative angiogenic cells.  相似文献   
102.
目的研究扁塑藤素对脂多糖(LPS)诱导人脐静脉血管内皮细胞(HUVEC)损伤的保护作用及可能机制。方法 建立LPS诱导HUVEC损伤模型,HUVEC细胞分为对照组、LPS组以及低、中、高剂量扁塑藤素组(0.1、0.2、0.4 μmol/L扁塑藤素)。CCK-8法测定细胞活力;试剂盒法检测乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)含量;ELISA法检测白细胞介素-1β(IL-1β)、IL-18蛋白水平;蛋白免疫印迹法、实时荧光定量PCR法检测焦亡相关分子NLRP3、Caspase-1、GSDMD蛋白和mRNA表达量。 结果与对照组比较,LPS组细胞活力和SOD含量显著下降(P<0.05),LDH和MDA含量、NLRP3、Caspase-1、GSDMD的蛋白和mRNA表达量均显著升高(P<0.05)。扁塑藤素呈剂量依赖性提高细胞活力和SOD含量,抑制LDH、MDA,降低NLRP3、Caspase-1、GSDMD的蛋白和mRNA表达水平(P<0.05)。 结论扁塑藤素呈剂量依赖性抑制细胞焦亡和减轻氧化应激,从而改善LPS诱导的HUVEC功能损伤。  相似文献   
103.
目的:观察风湿祛痛胶囊对血管内皮细胞生长因子(VEGF)诱导的人脐静脉内皮细胞(HUVEC)的增殖、迁移、黏附、侵袭和管腔形成能力的影响,以及对VEGF受体2(VEGFR2)的干预作用。方法:VEGF体外诱导HUVEC,加入风湿祛痛胶囊低、中、高质量浓度(0. 02,0. 1,0. 5μg·L-1)作用后,分别采用噻唑蓝(MTT)比色法、转移小室(transwell)法、黏附实验、细胞侵袭及管腔形成实验检测HUVEC的增殖活性、迁移、黏附、侵袭及管腔形成能力,蛋白免疫印迹法(Western blot)检测细胞中VEGFR2磷酸化水平和蛋白含量,实时荧光定量聚合酶链式反应(Real-time PCR)检测VEGFR2 mRNA表达水平。结果:与正常组比较,VEGF诱导24,48 h后均能显著升高HUVEC的增殖活性(P 0. 01),诱导24 h能明显升高HUVEC的迁移、黏附、侵袭和管腔形成能力(P 0. 01),显著升高HUVEC中VEGFR2磷酸化及蛋白和mRNA表达水平(P 0. 01);与VEGF组比较,风湿祛痛胶囊低、中、高质量浓度组作用48 h均能明显抑制HUVEC增殖活性(P 0. 05,P 0. 01),作用24 h对VEGF诱导的HUVEC迁移、黏附、侵袭和管腔形成能力有明显抑制作用(P 0. 05),也能下调VEGFR2磷酸化及蛋白和mRNA表达水平(P 0. 05)。结论:风湿祛痛胶囊能降低VEGF诱导的HUVEC细胞增殖、迁移、黏附、侵袭及管腔形成能力,这一作用可能与其抑制VEGFR2的磷酸化、蛋白和mRNA表达水平有关。  相似文献   
104.
    
Amphibian skin contains wound-healing peptides, antimicrobial peptides, and insulin-releasing peptides, which give their skin a strong regeneration ability to adapt to a complex and harsh living environment. In the current research, a novel wound-healing promoting peptide, PM-7, was identified from the skin secretions of Polypedates megacephalus, which has an amino acid sequence of FLNWRRILFLKVVR and shares no structural similarity with any peptides described before. It displays the activity of promoting wound healing in mice. Moreover, PM-7 exhibits the function of enhancing proliferation and migration in HUVEC and HSF cells by affecting the MAPK signaling pathway. Considering its favorable traits as a novel peptide that significantly promotes wound healing, PM-7 can be a potential candidate in the development of novel wound-repairing drugs.  相似文献   
105.
目的:研究萝卜硫素(SFN)促进人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC)生成一氧化氮(NO),参与内皮细胞修复的作用机制.方法:采用MTT法检测SFN对HUVEC细胞存活率的影响;检测SFN对HUVEC NO释放量的影响;采用Western blot法...  相似文献   
106.
    
Transplant rejection occurs following recipient recognition of mismatched HLA on donor tissue, but active rejection is dependent not only upon the severity of the T cell or alloantibody response, but also upon the cell surface expression of target HLA molecules. To investigate the variation in HLA expression using a model of endothelium, human umbilical vein endothelial cell (HUVEC) cultures were generated from 48 umbilical cords donated consecutively following planned caesarean section. HUVECs were stimulated using the cytokines tumour necrosis factor alpha and interferon gamma and HLA expression of unstimulated and stimulated cells determined using flow cytometry. HLA‐A2, HLA‐A3 and HLA‐C antigens all showed a modest increase in expression for 12 hours post cell activation, followed by a more pronounced response over the next 24 to 36 hours. Each of these antigens increased by up to 40 times over unstimulated levels and in addition cells homozygous for specific HLA antigens on average had twice the amount of antigen expressed compared with cells heterozygous for that antigen, both when unstimulated and following cytokine stimulation. Cell activation is an important consideration in the assessment of transplant risk and may help progress towards understanding why rejection does not always occur in the presence of significant donor specific antibody. This data also confirms guidelines for transplantation, which recommend doubling the specific antibody level when considering immunological risk for homozygous donors.  相似文献   
107.
108.
109.
复方苦参注射液联合热疗抗血管生成作用的实验研究   总被引:6,自引:1,他引:6  
目的探讨复方苦参注射液联合热疗对体内外血管生成的抑制作用。方法采用MTT法观察复方苦参注射液联合热疗对人脐静脉内皮细胞(讯舰C)、人结肠癌LOVO细胞增殖的影响;采用transwell板,观察复方苦参注射液对HUVEC迁移的影响;采用鸡胚绒毛尿囊膜(CAM)模型,观察复方苦参注射液对鸡胚绒毛尿囊膜新生血管的抑制作用。结果复方苦参注射液在6.25~200μL/L时具有抑制HUVEC增殖的作用(细胞存活率82.2%-32.5%),与浓度呈负相关(相关系数r及P值分别为一0.972、0.001),此浓度范围内对人结肠癌LOVO细胞增殖的抑制明显低于对HUVEC的抑制,具有明显的抗血管生成作用。12.5μL/mL和25μL/mL复方苦参注射液联合热疗在体外具有抗血管生成的协同效应,6.25μL/mL、50μL/mL、100μL/mL和200μL/mL复方苦参注射液联合热疗在体外具有抗血管生成的次加效应。复方苦参注射液在3.125~25μL/mL时具有抑制HUVEC迁移的作用,在12.5-50μL/mL时对鸡胚绒毛尿囊膜新生血管具有明显的抑制作用。结论小剂量复方苦参注射液在体内外具有抑制血管生成作用,联合热疗具有协同或次加效应。  相似文献   
110.
Studies indicate that oxidative modifications of endothelium and LDL play a preeminent role in atherogenesis; therefore, the preservation of the endothelial antioxidant capacity and the inhibition of LDL oxidation by use of plant-derived compounds are an appealing strategy against several vascular disorders. On this basis, baicalein, eupatorin, galangin, magnolol, myricetin, oleuropein, silibinin and bilobalide were studied against various oxidative conditions. The radical scavenging capacity was analysed using DPPH and ORAC assays. Furthermore, the LDL oxidation was detected by measuring the formation of thiobarbituric acid reactive substances (TBARS) and by monitoring the oxidation kinetics. Further, we used cultured HUVEC to investigate the activities of the polyhydroxyl compounds towards the oxidative stress induced by H2O2. The lowest levels of TBARS were observed in the presence of oleuropein and baicalein, while myricetin, magnolol and eupatorin inhibited these ones to a lesser extent. In addition, oleuropein and myricetin exhibited higher protection in copper-induced LDL oxidation kinetics. However, only myricetin and galangin showed significant protective effects against H2O2 oxidative injury in HUVEC cells. Taken all together the results indicate myricetin as the most active agent among the selected plant-derived polyhydroxyl compounds, with prominent capacities against ox-LDL and ROS production in HUVEC.  相似文献   
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