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1.
Pancreatic cancer (PC) is a cancer of the digestive system, and pancreatic ductal adenocarcinoma (PDAC) accounts for approximately 90% of all PC cases. Exosomes derived from PDAC (PDAC-exosomes) promote PDAC development and metastasis. Exosomes are nanoscale vesicles secreted by most cells, which can carry biologically active molecules and mediate communication and cargo transportation among cells. Recent studies have focused on transforming exosomes into good drug delivery systems (DDSs) to improve the clinical treatment of PDAC. This review considers PDAC as the main research object to introduce the role of PDAC-exosomes in PDAC development and metastasis. This review focuses on the following two themes: (a) the great potential of PDAC-exosomes as new diagnostic markers for PDAC, and (b) the transformation of exosomes into potential DDSs.  相似文献   
2.
目的:制备负载连翘苷(phil)的外泌体(exos)递药系统(phil-exos),并考察其对人肺上皮腺癌细胞A549迁移能力的影响。方法:采用差速-超高速离心法结合超滤法获取小鼠肺泡巨噬细胞(MHS)来源的外泌体,超声法制备phil-exos并测定其粒径及电位,采用透射电子显微镜观察其形态,蛋白质免疫印迹法鉴定标志蛋白CD63和Alix,激光共聚焦显微镜观察A549细胞对phil-exos的摄取,划痕实验考察其对A549细胞迁移能力的影响。结果:phil-exos的平均粒径为(139±1)nm,聚合物分散系数(PDI)为(0.237±0.023),Zeta电位为-(19.33±0.17)mV;外观呈类球状,具有茶托状膜结构;外泌体及phil-exos对Alix高表达,CD63低表达。A549细胞8 h时对phil-exos摄取良好,且24 h时phil的迁移抑制率为46.30%,phil-exos的迁移抑制率为81.99%,phil-exos对A549细胞迁移能力具有效抑制作用。结论:phil-exos制备成功,其可显著降低A549细胞的迁移能力。  相似文献   
3.
外泌体是一类直径为30~100 nm的圆盘囊泡,其内包含许多组分,诸如复杂RNA和蛋白质等,主要参与细胞间的信号转导。肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)是肿瘤微环境中普遍存在的巨噬细胞,通过对肿瘤生长、免疫逃逸、侵袭和转移、耐药性等多方面的作用影响肿瘤进程。外泌体在肿瘤相关巨噬细胞的招募、极化及抗肿瘤免疫调控等方面发挥着重要的调节功能。同时,TAMs以外泌体为媒介作用于肿瘤细胞,从而构成了外泌体、TAMs与肿瘤细胞之间相互作用的调控通路。综上所述,本文旨在阐明肿瘤细胞与TAMs之间,以外泌体为“桥梁”相互影响的潜在机制,以及靶向肿瘤细胞和TAMs来源的外泌体在恶性肿瘤治疗中的展望。  相似文献   
4.
目的观察病毒性心肌炎(VMC)病儿血浆外泌体微小RNA(miR)-148a的水平并分析其意义。方法选择2017年9月至2019年6月郑州大学附属儿童医院收治的VMC病儿112例纳入研究组,另选取同期门诊健康体检正常儿童112例为对照组,实时荧光定量PCR(RT-qPCR)检测血浆外泌体miR-148a水平,酶联免疫吸附测定(ELISA)检测血浆外泌体心肌肌钙蛋白I(cTnI),采用自动化生化仪检测血浆外泌体肌酸激酶同工酶(CK-MB)水平、超敏C反应蛋白(hs-CRP)水平。采用Pearson相关性分析检验VMC病儿血浆外泌体miR-148a与cTnI、CK-MB、hs-CRP水平的相关性。绘制受试者工作特征曲线(ROC)分析血浆外泌体miR-148a对VMC的诊断价值。结果血浆外泌体在透射电镜下呈大小不等、直径约100 nm典型圆形或椭圆形囊泡结构。与对照组比较,研究组血浆外泌体miR-148a水平[(1.01±0.12)比(5.34±1.06)]、血浆cTnI、CK-MB、hs-CRP水平均增加(均P<0.001)。VMC病儿血浆外泌体miR-148a与血浆cTnI、CK-MB、hs-CRP水平均呈正相关(r=0.62、0.64、0.49,均P<0.001)。血浆外泌体miR-148a及血浆cTnI、CK-MB、hs-CRP诊断早期VMC的曲线下面积(AUC)分别为0.94、0.94、0.83、0.86,截断值分别为1.87、0.19 μg/L、56.45 U/L、2.06 mg/L,灵敏度分别为94.60%、92.90%、84.80%、83.90%,特异度分别为92.90%、94.60%、83.90%、83.90%。血浆外泌体miR-148a与血浆cTnI诊断早期VMC的效能一致,均优于血浆CK-MB、hs-CRP。结论VMC病儿血浆外泌体miR-148a水平上调,可能对VMC有一定诊断价值。  相似文献   
5.
目的探究肿瘤相关成纤维细胞外泌体对肺癌细胞生长和转移的影响及机制。方法取肺癌患者的癌组织和癌旁组织分离肿瘤相关成纤维细胞(Cancer-associated fibroblasts,CAFs)和成纤维细胞(Normal Fibroblasts,NFs),免疫荧光和Western blot鉴定CAFs和NFs中α-SMA、FSP-1、FAP、Vimentin表达,差速离心法提取CAFs和NFs细胞外泌体,利用透射电镜和Western blot鉴定外泌体,将外泌体与肺癌细胞A549共孵育后检测细胞增殖、迁移、侵袭、细胞凋亡水平,Western blot检测PI3K/AKT/mTOR信号通路激活水平。结果α-SMA、FSP-1、FAP、Vimentin高表达于CAFs;透射电镜和Western blot鉴定外泌体符合其特征;与PBS组相比,与CAFs外泌体共孵育组A549细胞增殖、迁移、侵袭能力显著增加(P<0.001),细胞凋亡水平显著降低(P<0.001),PI3K、AKT、mTOR磷酸化水平显著增加,而与NFs外泌体共孵育后细胞增殖、迁移、侵袭以及凋亡水平无显著变化,PI3K、AKT、mTOR磷酸化水平无显著变化。结论肿瘤相关成纤维细胞外泌体能够通过激活PI3K/AKT/mTOR信号通路,而促进肺癌细胞的生长和转移。  相似文献   
6.
《Molecular therapy》2022,30(2):763-781
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7.
非小细胞肺癌(non-small cell lung cancer,NSCLC)是肺癌中最常见的类型,对化疗及靶向药物的获得性耐药严重影响NSCLC患者的生存期,NSCLC获得性耐药机制复杂,确切机制仍不清楚。肿瘤来源或与肿瘤相关的外泌体是参与调控NSCLC获得性耐药的重要机制,可以通过传递核酸、蛋白质等赋予敏感细胞耐药性。本综述主要介绍近年来外泌体非编码RNA(non-coding RNA,ncRNA)在NSCLC获得性耐药中的研究进展。   相似文献   
8.
《Saudi Dental Journal》2022,34(5):346-354
BackgroundLipopolysaccharides (LPS) stimulate production of inflammatory cytokines. Chrysin is flavonoid beneficial for treatment of inflammatory conditions. Bone marrow mesenchymal stem cell (BM-MSC) exosomes have regenerative ability in different tissues.ObjectiveTo assess potential role of chrysin and BM-MSC exosomes on ultra-structure, viability and function of human dermal fibroblasts-adult (HDFa) stimulated by LPS.MethodsHDFa cells were divided into: Group I: Cells received no treatment. Group II: Cells were stimulated with LPS. Group III: LPS stimulated cells were treated with chrysin. Group IV: LPS stimulated cells were treated with exosomes.ResultsAfter 48 h, ultrastructural examination of HDFa cells in Group I revealed intact plasma membrane and numerous cytoplasmic organelles. Group II displayed destructed plasma membrane and apoptotic bodies. Group III showed intact plasma membrane with loss of its integrity at some areas. Group IV demonstrated intact plasma membrane that showed fusion with exosomes at some areas. Statistical analysis of MTT represented highest mean value of cell viability% in Group IV followed by Groups III, I and II respectively. Statistical analysis of enzyme-linked immunosorbent assay (ELISA) showed the highest mean value of interleukin-1β (IL-1β) was in Group II followed by Groups III, IV and I, while highest mean values of interleukin-10 (IL-10), nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins were in Group I, followed by Groups IV, III and II respectively.ConclusionsLPS have harmful consequences on ultra-structure, viability and function of HDFa cells. BM-MSC exosomes have better regenerative action on inflamed fibroblasts in comparison to chrysin.  相似文献   
9.
刘士鑫  吴瑾 《现代肿瘤医学》2022,(18):3423-3428
卵巢癌是妇科肿瘤领域内的一个热点主题。该种恶性肿瘤疾病的发病率高且隐匿,缺乏有效的早期发现及时诊断并治疗的方式,病情容易加重发生远处转移。因此罹患卵巢癌的女性5年生存率比较低。外泌体属于一类典型的囊性泡样的小体,参与肿瘤的发病及转移机制且在肿瘤疾病的治疗中起着重要作用。本篇综述主要介绍癌细胞外泌体在卵巢恶性肿瘤疾病的诊断、转移及治疗中的研究现状。  相似文献   
10.
The natural behavior of mesenchymal stem cells (MSCs) and their exosomes in targeting tumors is a promising approach for curative therapy. Human tumor tropic mesenchymal stem cells (MSCs) isolated from various tissues and MSCs engineered to express the yeast cytosine deaminase::uracil phosphoribosyl transferase suicide fusion gene (yCD::UPRT-MSCs) released exosomes in conditional medium (CM). Exosomes from all tissue specific yCD::UPRT-MSCs contained mRNA of the suicide gene in the exosome's cargo. When the CM was applied to tumor cells, the exosomes were internalized by recipient tumor cells and in the presence of the prodrug 5-fluorocytosine (5-FC) effectively triggered dose-dependent tumor cell death by endocytosed exosomes via an intracellular conversion of the prodrug 5-FC to 5-fluorouracil. Exosomes were found to be responsible for the tumor inhibitory activity. The presence of microRNAs in exosomes produced from naive MSCs and from suicide gene transduced MSCs did not differ significantly. MicroRNAs from yCD::UPRT-MSCs were not associated with therapeutic effect. MSC suicide gene exosomes represent a new class of tumor cell targeting drug acting intracellular with curative potential.  相似文献   
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