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101.
Nanoparticle and liposome formulations containing doxycycline or doxycycline and sodium taurocholate (NaTC) were developed in this study. The anticancer effects of doxycycline and penetration properties from those formulations through Caco-2 cell monolayers were investigated. Matrix metalloproteinases (MMPs) have been reported to play a role in the negative prognosis of many malignant tumors including glioblastoma multiforme (GBM). This study is presented to demonstrate that these developed nanoparticle and liposome formulations of doxycycline are capable of inhibiting MMP-2 release from cultured Caco-2 cells. In this study, Caco-2 cells were used as model cell cultures. A MTT test was performed to determine the effect of doxycycline on the viability of Caco-2 cells. Doxycycline nanoparticles were prepared using emulsion polymerization and doxycycline liposomes were prepared using the dry film hydration method. Transport studies of doxycycline through Caco-2 cells were investigated. MMP-2 was found to be inhibited more with doxycycline if NaTC is present in the formulation. NaTC was also found to be useful to increase penetration due to the inhibition of efflux by interacting with p-glycoproteins, in addition to the penetration enhancing effect as a result of opening tight junctions. These developed formulations were proposed to use for the treatment of tumors and GBM.  相似文献   
102.
目的探讨人肺腺癌细胞总RNA转染的树突状细胞(DCs)诱导抗原特异性的细胞毒T细胞(CTLs)对移植瘤裸鼠的抗肿瘤作用。方法 1)从外周血单个核细胞(PBMCs)中诱导DCs,提取人肺癌细胞A549总RNA,用于电转染DCs,转染后的DCs与自体T细胞混合培养,诱导抗原特异性的CTLs;2)实验分为转染RNA的DCs组、转染PBS的DCs组和未转染DCs组,流式细胞术(FCM)鉴定T细胞表型,3H-TdR掺入检测T细胞增殖能力;3)建立肺癌细胞株A549荷瘤裸鼠模型,过继回输CTLs,比较肿瘤体积,计算抑瘤率,免疫组化法检测移植瘤组织中Bax、Bcl-2、COX-2和VEGF的表达,并用全自动图像分析系统分析其平均光密度值(MOD)。结果 1)转染RNA的DCs和自体T细胞共育诱导的CTLs的CD8+T细胞大幅度上调,表达率(79.29±2.18)%明显高于转染PBS的DCs组CD8+T细胞(26.10±1.76)%和未转染DCs组CD8+T细胞(25.58±2.73)%(P0.05);2)转染RNA的DCs显著刺激了自体T细胞增殖,3H-TdR渗入所得的cpm值:阳性对照组为17 105±130,转染RNA的DCs组为7 759±493,转染PBS的DCs组为2 611±161,未转染DCs组为2 248±332(P0.05);3)成功建立肺癌裸鼠移植瘤模型,实验结束时,转染RNA组裸鼠荷瘤体积(540±99)mm3明显小于转染PBS组(1 572±147)mm3和未转染组(2 043±395)mm3(P0.05);4)转染RNA组和转染PBS组的抑瘤率分别为68.53%和8.62%;5)转染RNA的DCs诱导的CTLs能显著上调Bax的表达(转染RNA组MOD值为335±105),显著下调Bcl-2、COX-2和VEGF的表达(转染RNA组MOD值分别为146±47、122±33和128±58)。结论人肺腺癌细胞总RNA转染DCs诱导的抗原特异性CTLs对肺腺癌裸鼠移植瘤的生长产生抑制作用。  相似文献   
103.
异黄酮类物质是一类来自天然植物的多酚类化合物,因其具有明显的生物学活性,已愈来愈受到国内外学者的广泛关注,成为了近年来医药学领域研究的热点。本文对近年来异黄酮类物质抗肿瘤作用机制的研究成果进行综述,并对其开发及应用前景作出了展望。  相似文献   
104.
From the anti-tumor active N-tryptophanyl-β-carboline-3-carboxylic acid benzyl ester and β-carboline-3-carbonyltryptophan benzyl ester, a pharmacophore, Trp-Trp-OBzl, was drawn. Based on the DOCK scores amino acid residue was inserted into the C-terminus of Trp-Trp-OBzl and twenty Trp-Trp-AA-OBzls (AA = amino acid residues) were provided as DNA intercalators. On the in vitro and in vivo models seventeen Trp-Trp-AA-OBzls were anti-tumor active, and twelve Trp-Trp-AA-OBzls were more active than cytarabine. In acute toxicity assay Trp-Trp-AA-OBzls did not damage the immunologic function and had an LD50 of more than 500 mg/kg. The relationships of structure and activity were analyzed with 3D QSAR. The action mechanism studies revealed that the in vivo anti-tumor action of Trp-Trp-AA-OBzls was the result of DNA intercalation.  相似文献   
105.
目的:建立一种基于荧光成像的抗肿瘤药物体外快速筛选系统.方法:①采用二乙酸荧光素(FDA)标记测定活细胞数法,评价26个乌药组分对的体外抗肿瘤活性,并对本方法的线性范围和精密度进行了考察;②在活性筛选结果的指导下,应用LC/MS对样品进行分析,初步推断药效活性物质.结果:①该方法在细胞密度为0~ 10 000/孔的范围内荧光强度与细胞个数线性相关(r2 =0.9858),板内的精密度为9.41%;②在26个乌药组分中,筛选得到两个抗肿瘤活性较强的组分C13和C15,抑制率均达到90%以上.结论:本方法快速、稳定、简便、线性范围宽,可用于从复杂中药组分中快速筛选抗肿瘤活性物质.此外,根据LC/MS分析结果并结合文献报道,推断乌药中具有抗肿瘤活性的化合物为异波尔定碱.  相似文献   
106.
[目的]研究赤104#色素的亚慢性毒性作用。[方法]根据GB 15193-2003《食品安全性毒理学评价程序和方法》设1.08、3.25、9.75、29.25mg/kg四个剂量组,进行大鼠亚慢性毒性试验研究。[结果]赤104#色素大鼠亚慢性毒性试验各剂量组各指标均未显示明显毒性作用。[结论]在本次实验条件下,赤104#色素在29.25mg/kg剂量下未显示有毒性作用。  相似文献   
107.
ObjectiveTo investigate the potential anti-tumor mechanisms of naphthoquinone compound shikonin (SKN) extracted from the root of Chinese herbal medicine plant lithospermum (Lithospermum erythrorhizon Sieb. & Zucc.).MethodsWe first observed that SKN treatment led to swelling and bubbles in HeLa cells that were similar to the phenotype of cell pyroptosis. Subsequently, the HeLa cells experienced a pyroptotic process with SKN, and this was then assessed using lactate dehydrogenase (LDH) release and propidium iodide (PI)/Hoechst double staining experiments. Pyroptosis is defined as gasdermin-mediated programmed necroptosis. To identify the potential pyroptosis machinery, two strategies were utilized that included a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 screening experiment and a pyroptosis reconstitution assay executed by each of the five known gasdermins (GSDMA-E). Moreover, endogenous cleavage was also detected in a panel of tumor cell lines.ResultsCompared with the control, both the LDH release and PI/Hoechst double-staining experiments suggested that SKN induced perforation and enhancement of the permeability of the cell membranes that resulted in pyroptosis in HeLa cells (P = .028 and P = .032, respectively). In addition, the reconstitution assays in human embryonic kidney 293T (HEK-293T) cells and endogenous cleavage assays in HeLa cells indicated that the pyroptosis was controlled by GSDME. In addition, we also found SKN could trigger pyroptosis in a panel of tumor cell lines in which the cellular morphologies were proportional to the GSDME expression levels. Additionally, the cleavage of GSDME was also detected, and this was indicative of a similar GSDME-mediated mechanism.ConclusionOur study not only explained the molecular mechanism of cytotoxicity of SKN to various tumor cells, but also provided additional information for the potential clinical application of natural naphthoquinone compounds against cancer.  相似文献   
108.
目的:探讨黄连素对人胃癌细胞SGC7901凋亡的影响。方法:MTS法检测不同浓度的黄连素(100、150、200μmol/L)对胃癌细胞的抑制作用,Hoechst 33258染色检测不同浓度的黄连素(100、150、200μmol/L)对细胞凋亡的影响;Real Time Q-PCR检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的mRNA表达;Western blot检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的蛋白表达。结果:不同浓度的黄连素能显著降低人胃癌细胞SGC701活性(P<0.05,P<0.01),促进其凋亡,升高Cleaved Caspase-3、Bax的mRNA和蛋白表达水平(P<0.05,P<0.01),降低Bcl-2的mRNA和蛋白表达水平(P<0.05,P<0.01)。结论:不同浓度的黄连素可诱导胃癌细胞凋亡,其机制可能与升高Cleaved Caspase-3、Bax的表达,降低Bcl-2的表达有关。  相似文献   
109.
110.
As a traditional Chinese herbal medicine, Pulsatilla Chinensis (P. Chinensis) is widely used in the clinical practice of traditional Chinese medicine (TCM). Recently, medical research has found that the natural product P. Chinensis saponins and their monomeric compounds extracted from P. Chinensis have a variety of biological activities, especially the triterpenoid saponins, which have significant and broad-spectrum anti-tumor effects. Moreover, its anti-tumor molecular mechanisms include inhibition of the growth and proliferation of tumor cells, repression of the migration, invasion, and metastasis, prevention of tumor cell cycle, regulation of cancer cell energy metabolism, anti-tumor angiogenesis, induction of cancer cell differentiation, apoptosis and autophagy, reversing cancer cell resistance, regulation a variety of related signaling pathways, and improvement of the inflammatory microenvironment of tumor cells. In the present work, we reviewed the related anticancer mechanisms of P. Chinensis saponins and their monomers in different tumors, aiming to provide a theoretical basis for the development and clinical application of new anti-tumor drugs of P. Chinensis saponins and their monomeric compounds.  相似文献   
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