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1.
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination, a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid progression and dissemination of the disease.  相似文献   
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血管生成拟态(vasculogenic mimicry,VM)是血管依赖性实体肿瘤中一种无内皮细胞的“血管样”结构,是肿瘤在高度侵袭过程中的一种特殊的供血模式。VM广泛存在于多种人体恶性肿瘤中,与肿瘤的进展、转移、侵袭和复发密切相关。本文将就胶质瘤血管生成拟态的发生机制、信号通路途径以及分子调控机制等作一综述,并探讨目前研究中面临的问题,旨在为胶质瘤的基因治疗的新切入点提供理论依据。  相似文献   
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任可  周静  李振麟  钱士辉  李贺  王宸 《中草药》2019,50(1):120-128
目的探讨重楼提取物(PPEE)抗骨肉瘤作用及其机制。方法不同质量浓度的PPEE处理骨肉瘤细胞,采用MTT法、Hoechst 33342染色、流式细胞术、Matrigel培养、免疫印迹法分别检测细胞增殖抑制率、细胞凋亡、细胞周期、血管生成拟态(VM)形成及相关蛋白表达情况。裸鼠移植瘤模型观察PPEE的体内抑瘤效果。结果 PPEE对骨肉瘤细胞半数抑制浓度(IC50)为10~60μg/m L,对成骨细胞增殖影响较小。PPEE可浓度依赖性地将骨肉瘤143B细胞阻滞在G2/M期,上调细胞周期相关蛋白p-CDK1、p-Cdc25C、p-Chk2表达,下调cyclinB1表达;促进细胞凋亡,上调cleavedCaspase-3、8、9和PARP表达,上调Bax/Bcl-2;抑制细胞体外VM形成,下调FAK、Mig-7、MMP-2和MMP-9表达。体内实验显示PPEE能明显抑制骨肉瘤生长和体内VM形成,延长荷瘤裸鼠生存期。结论 PPEE在体内外均具有良好的抗骨肉瘤活性,其作用机制可能与诱导骨肉瘤细胞凋亡、阻滞细胞周期及破坏骨肉瘤VM形成有关。  相似文献   
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Autoimmune hepatitis (AIH) is a severe form of hepatitis resulting in the autoimmune-mediated destruction of the liver parenchyma. Whereas many of the immunopathogenic events have been elucidated and some of the drivers of the disease have been identified, little is known about the aetiology of the disease. There are certain risk factors, such as particular human leucocyte antigen (HLA) haplotypes, that enhance the susceptibility for AIH or influence the severity of the disease. However, as for many other autoimmune diseases, the mere presence of such risk factors does not warrant the occurrence of the disease. Not all individuals carrying risk factors develop AIH, and not all patients with AIH are carriers of high-risk alleles. Thus, additional environmental factors need to be considered as triggers for AIH. Environmental factors include diet, sunlight exposure, stress, medication and hygiene, as well as pathogen infections and vaccinations. This review discusses if pathogens should be considered as triggers for the initiation and/or propagation of AIH.  相似文献   
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Primary biliary cholangitis (PBC) is a multi-factorial disease caused by the interaction of both genetic predisposition and environmental triggers. Bacterial infection has been investigated most intensively, both epidemiologically and experimentally, as a prime environmental aetiology in PBC. The association of recurrent history of urinary tract infection (UTI) with PBC has been frequently confirmed by several large-scale, case–control studies, despite variation in geographic area or case-finding methods. Escherichia coli is a predominant pathogen in most cases with UTI. Animal studies and molecular mimicry analysis between the human and E. coli E2 subunit of the 2-oxo-acid dehydrogenase complexes demonstrated that E. coli infection is a key factor in breaking immunological tolerance against the mitochondria, resulting in the production of anti-mitochondrial autoantibodies (AMA), the disease-specific autoantibodies of PBC. Novosphingobium aromaticivorans, a ubiquitous xenobiotic-metabolizing bacterium, is another candidate which may be involved in the aetiology of PBC. Meanwhile, improved environmental hygiene and increased prevalence of PBC, especially in males, may argue against the aetiological role of bacterial infection in PBC. Multiple mechanisms can result in the loss of tolerance to mitochondrial autoantigens in PBC; nonetheless, bacterial infection is probably one of the dominant pathways, especially in female patients. Notably, there is a rising prevalence of male patients with PBC. With increasing exposure to environmental xenobiotics in both genders, studies directed towards identifying the environmental culprit with systematically designed case–control studies are much needed to further determine the environmental factors and role of bacterial infections in PBC.  相似文献   
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Chemotherapy for non‐small cell lung cancer (NSCLC) is far from satisfactory, mainly due to poor targeting of antitumor drugs and self‐adaptations of the tumors. Angiogenesis, vasculogenic mimicry (VM) channels, migration, and invasion are the main ways for tumors to obtain nutrition. Herein, RPV‐modified epirubicin and dioscin co‐delivery liposomes were successfully prepared. These liposomes showed ideal physicochemical properties, enhanced tumor targeting and accumulation in tumor sites, and inhibited VM channel formation, tumor angiogenesis, migration and invasion. The liposomes also downregulated VM‐related and angiogenesis‐related proteins in vitro. Furthermore, when tested in vivo, the targeted co‐delivery liposomes increased selective accumulation of drugs in tumor sites and showed extended stability in blood circulation. In conclusion, RPV‐modified epirubicin and dioscin co‐delivery liposomes showed strong antitumor efficacy in vivo and could thus be considered a promising strategy for NSCLC treatment.  相似文献   
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目的 探讨逆转录病毒介导的短发夹RNA(shRNA)干扰迁移诱导基因7(Mig-7)对肝细胞癌(HCC)细胞血管生成拟态(VM)形成及体外侵袭转移能力的影响.方法 设计2条Mig-7 mRNA寡核苷酸序列(Mig-7 shRNA-1,Mig-7 shRNA-2)和1条作为负对照的无关序列(Mig-7 shRNA-N).构建Mig-7shRNA逆转录病毒表达载体质粒,并将要接受转染的人肝癌细胞MHCC-97H分为6组:转染Mig-7 shRNA-1组;转染Mig-7 shRNA-2组;转染Mig-7 shRNA-N组;转染空载质粒组(Vector);重组人血管内皮抑素(ES,商品名:恩度)组;MHCC-97H细胞对照组(Control).半定量PCR、Western blot检测其对Mig-7表达的影响;三维细胞培养观察其对VM形成的影响;细胞间粘附实验、Transwell侵袭实验及迁移实验观察其对细胞粘附、侵袭及迁移能力的影响.结果 转染后,Mig-7 shRNA-1组与Mig-7 shRNA-2组中Mig-7 mRNA与蛋白的表达、MHCC-97H细胞形成VM能力、细胞侵袭、迁移能力明显减低(P<0.05),细胞间粘附能力明显增加(P<0.05);Mig-7 shRNA-N组、Vector组、ES组中MHCC-97H细胞Mig-7的表达、VM形成、细胞间粘附、迁移、侵袭能力较MHCC-97H细胞组均无明显变化.结论 逆转录病毒介导的shRNA能够有效下调Mig-7的表达并明显抑制HCC细胞VM形成能力及侵袭转移能力,增加细胞间的粘附作用;ES对HCC细胞的Mig-7表达、VM形成、侵袭转移及粘附能力无明显影响.  相似文献   
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胡佳丽  高玉 《国际眼科杂志》2016,16(8):1477-1479
视网膜母细胞瘤( retinoblastoma ,Rb)是眼内常见恶性肿瘤之一,恶性程度高,危害大。传统的治疗方法破坏性强,预后不佳。低氧诱导因子-1α在Rb中高表达,影响肿瘤细胞的分化增殖及转移,参与血管生成拟态的生成,进而调控Rb的整个发生发展过程。本文将对低氧诱导因子-1α在Rb发生发展中的作用做一综述,以期为Rb的治疗开辟新的途径。  相似文献   
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