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1.
《Molecular therapy》2022,30(1):32-46
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2.
IntroductionThe lymph node ratio (LNR), which represents the proportion of metastatic lymph nodes resected, has been found to be a prognostic variable in several cancers, but data for Medullary thyroid carcinoma (MTC) are sparse. The aim of this study was to determine the value of the LNR in predicting outcome in patients with MTC.Materials and methodsA retrospective multicenter study design of 107 patients with MTC who underwent total thyroidectomy with neck dissection between 1984 and 2016. The association of LNR with patient and tumor characteristics and prognostic factors was evaluated.ResultsStudy population consisted of 53.3% female, mean age at diagnosis was 50.3 ± 18.4 years; 16.8% had inherited MTC. LNR was positively correlated with tumor size (p = 0.018) and inversely correlated with age at diagnosis (p = 0.024). A higher LNR was associated with extrathyroidal extension (p < 0.001), multifocality (p = 0.001), bilateral tumor (p = 0.002), distant metastases (p < 0.001), and tumor recurrence (OR = 14.7, p < 0.001). LNR was also correlated to postoperative calcitonin levels (p < 0.001) and carcinoembryonic antigen (p = 0.011). LNR >0.1 was associated with shorter disease-specific survival in patients at risk: tumor larger than 20 mm at diagnosis (p = 0.013), sporadic MTC (p = 0.01), and age above 40 years at diagnosis (p = 0.004). Cox multivariate survival analysis revealed LNR as the only significant independent factor for disease free survival (p = 0.005).ConclusionsThis study showed that LNR correlates well with patient and tumor characteristics and prognostic variables. We suggest that LNR should be considered an important parameter for predicting outcome in MTC.  相似文献   
3.
目的:研究鱼藤素(De)诱导SGC-7901胃癌细胞凋亡的其作用机制。方法:运用CCK-8细胞活力检测法考察不同浓度(10、20、40、60、80、100 mol/L)鱼藤素作用24、48 h对SGC-7901胃癌细胞的细胞毒性;将SGC-7901胃癌细胞分为对照组及20、40 mol/L鱼藤素药物组,给药作用24 h后,蛋白质印迹法检测p-AKTThr308、叉头框蛋白O1(FoxO1)、B淋巴细胞瘤-2基因(Bcl-2)等蛋白的表达水平;运用蛋白激酶B(AKT)基因转染使SGC-7901胃癌细胞中AKT过表达,然后给予20、40 mol/L鱼藤素给药作用24 h,以未用AKT基因转染的SGC-7901胃癌细胞作为对照组蛋白质印迹法检测p-AKTThr308、FoxO1、Bcl-2等蛋白的表达水平,实时荧光定量PCR(RT-qPCR)检测FoxO1、Bcl-2、Bax mRNA的表达水平。结果:不同浓度的鱼藤素对SGC-7901胃癌细胞均具有一定的细胞毒性;20、40 mol/L鱼藤素给药作用24 h能够显著降低SGC-7901胃癌细胞中p-AKTThr308、Bcl-2等蛋白的表达水平,升高FoxO1的表达水平;与对照组比较,AKT基因转染后,SGC-7901胃癌细胞中p-AKTThr308、Bcl-2等蛋白表达水平升高,FoxO1蛋白表达降低,与模型组比较,20、40 mol/L鱼藤素给药作用后能够降低p-AKTThr308、Bcl-2等蛋白的表达水平,降低Bcl-2 mRNA的表达水平,升高FoxO1及Bax的表达水平。结论:鱼藤素能够通过作用于AKT/FoxO1信号通路诱导胃癌细胞SGC-7901凋亡。  相似文献   
4.
目的:探究miRNA-132(miR-132)通过Hedgehog 信号通路对肝细胞癌细胞凋亡的机制。方法:用miR- 132 类似物转染人肝癌HepG2 细胞,将样本分为空白组( 无转染HepG2)、NC组(HepG2 转染miR-132-NC)、 YJ 组(HepG2 转染miR-132 mimic)。通过qRT-PCR 检测miR-132 在HepG2 细胞中的表达量,采用CCK-8 法、流 式细胞仪、Transwell 小室、免疫印迹检测细胞增殖、凋亡、侵袭能力以及Shh 蛋白表达。结果:PCR检测结果显示, 3 组对比,YJ 组HepG2 细胞中miR-132 表达量最高,说明转染成功;CCK-8 检测结果显示,YJ 组HepG2 细胞增 殖数量最低,空白组HepG2 细胞的增殖与NC组相似,皆高于YJ 组;流式细胞检测结果显示,与NC组及空白组 比较,YJ 组HepG2 细胞凋亡数量最多 ;Transwell 小室检测结果显示, YJ 组细胞侵袭数量与空白组和NC组相比 明显降低,空白组细胞侵袭数量与NC组相比数据接近;免疫印迹检测结果显示,YJ 组Shh 蛋白相对表达量与空 白组和NC组比明显降低。结论:过表达miR-132 降低Hedgehog 信号通路,可促进人肝癌HepG2 细胞凋亡作用。  相似文献   
5.
Sindbis virus (SINV), a positive-sense single stranded RNA virus that causes mild symptoms in humans, is transmitted by mosquito bites. SINV reverse genetics have many implications, not only in understanding alphavirus transmission, replication cycle, and virus-host interactions, but also in biotechnology and biomedical applications. The rescue of SINV infectious particles is usually achieved by transfecting susceptible cells (BHK-21) with SINV-infectious mRNA genomes generated from cDNA constructed via in vitro translation (IVT). That procedure is time consuming, costly, and relies heavily on reagent quality. Here, we constructed a novel infectious SINV cDNA construct that expresses its genomic RNA in yeast cells controlled by galactose induction. Using spheroplasts made from this yeast, we established a robust polyethylene glycol-mediated yeast: BHK-21 fusion protocol to rescue infectious SINV particles. Our approach is timesaving and utilizes common lab reagents for SINV rescue. It could be a useful tool for the rescue of large single strand RNA viruses, such as SARS-CoV-2.  相似文献   
6.
BACKGROUNDFine-needle biopsy is an accurate and cost-efficient tool for the assessment of thyroid nodules. It includes two primary methods: Fine-needle capillary biopsy (FNCB) and fine-needle aspiration biopsy. Needle tract seeding (NTS) is a rare complication of thyroid fine-needle biopsy mainly caused by fine-needle aspiration biopsy rather than FNCB. Here, we present an extremely rare case of a papillary thyroid carcinoma (PTC) patient with FNCB-derived NTS. CASE SUMMARYWe report a 32-year-old woman with PTC who showed subcutaneous NTS 1 year after FNCB and thyroidectomy. NTS was diagnosed based on clinical manifestations, biochemistry indices, and imaging (computed tomography and ultrasound). Pathological identification of PTC metastases consistent with the puncture path is the gold standard for diagnosis. Surgical resection was the main method used to treat the disease. After surgery, thyroid function tests and ultrasound scans were performed every 3-6 mo. To date, no evidence of tumor recurrence has been observed.CONCLUSIONFNCB is a safe procedure as NTS is rare, and can be easily removed surgically with no recurrence. Accordingly, NTS should not limit the usefulness of FNCB.  相似文献   
7.
背景与目的:食管癌是全球威胁人类生命和健康的常见恶性肿瘤之一,中国每年食管癌发病人数占全球发病总人数的一半以上,以食管鳞癌最为常见。放疗是食管癌三大治疗手段之一,而放射抗性是导致其治疗失败的主要原因。神经营养因子受体相互作用MAGE类药物(neurotrophin receptor-interacting MAGE homolog,NRAGE)在放射抗性细胞株TE13R120中表达量明显高于亲本TE13细胞,且NRAGE亚细胞定位变化可能参与食管癌细胞放射抗性的形成。通过基因转染构建NRAGE稳定表达的食管癌细胞系,以进一步明确NRAGE基因与食管鳞癌细胞放射抗性的关系,分析该基因影响放射抗性的具体机制。方法:通过基因转染构建NRAGE稳定表达的食管癌细胞系。采用细胞克隆形成实验检测细胞放射敏感性,采用流式细胞术检测细胞周期及凋亡;细胞划痕、Transwell侵袭实验检测细胞迁移、侵袭能力,采用实时荧光定量聚合酶链反应(real-time fluorescence quantitive polymerase chain reaction,RTFQ-PCR)和蛋白质印迹法(Western blot)检测细胞中β-catenin表达情况。组间差异采用t检验或方差分析。结果:实验分为转染过表达组(Eca109/NRAGE组)和空白对照组(Eca109组)。Eca109/NRAGE细胞中NRAGE的表达量明显高于Eca109(t=29.65,P<0.05)。照射后Eca109/NRAGE细胞的放射抗性显著高于Eca109。流式细胞术检测结果显示,Eca109/NRAGE细胞中对射线抵抗性最强的S期细胞比例增加,对射线最敏感的G 2 /M期减少。Eca109/NRAGE细胞凋亡率较Eca109细胞降低(t=3.268,P<0.05)。Eca109/NRAGE细胞迁移和侵袭能力均高于Eca109。RTFQ-PCR和Western blot检测结果显示,β-catenin的mRNA表达及蛋白水平在Eca109/NRAGE细胞中明显高于Eca109(t=15.87,P<0.05)。结论:NRAGE参与Eca109细胞放射抗性的形成,改变细胞的细胞周期分布和凋亡情况,影响细胞迁移及侵袭能力并可能影响食管癌细胞的放射敏感性,该作用可能与激活Wnt/β-catenin信号转导通路有关。  相似文献   
8.
背景:研究表明Asxl1的缺失可导致骨质发育不全、骨质缺损类疾病的发生,但目前在根尖周炎环境下该因子与骨破坏之间的关系暂无相关报道。目的:探讨炎性微环境下Asxl1对成骨细胞增殖分化的影响。方法:实验选用脂多糖刺激MC3T3-E1细胞建立体外炎性微环境,通过CCK-8实验筛取脂多糖最佳质量浓度和最佳作用时间,然后用20 mg/L脂多糖刺激MC3T3-E1细胞24 h,免疫荧光检测Asxl1的蛋白表达水平,Real Time-PCR检测Asxl1 mRNA的表达水平。为进一步验证Asxl1基因在炎性微环境中影响成骨细胞的增殖与分化,脂多糖刺激形成炎性微环境后转染Asxl1-SiRNA 24 h,采用CCK-8检测细胞增殖活性,RealTime-PCR检测Asxl1及成骨相关基因ALP和RUNX2 mRNA的表达水平。结果与结论:①脂多糖刺激MC3T3-E1细胞后,Asxl1蛋白和mRNA表达水平呈降低趋势;②脂多糖刺激MC3T3-E1细胞后,转染Asxl1-SiRNA 24 h,细胞增殖活性下降趋势明显,Asxl1基因及成骨相关基因ALP和RUNX2 mRNA的表达水平明显降低;③结果提示,Asxl1可能通过参与炎性反应过程,影响成骨细胞的增殖与分化,进而参与骨破坏进程。  相似文献   
9.
Background: Achieving long-term gene expression in kidney will be beneficial for gene therapy of renal and congenital diseases, genetic studies constructing animal disease models, and the functional analysis of disease-related genes.

Purpose: The purpose of this study was to develop an in vivo long-term gene expression system in murine kidney using ?C31 integrase.

Methods: Gene expression in cultured RENCA, TCMK-1, and HEK293 cells was assessed. The long-term in vivo gene expression system in the kidney was achieved by co-transfecting 5?µg of pORF-luc/attB as a donor plasmid and 20?µg of pCMV-luc as a helper plasmid into the right kidney of mice by electroporation. Luciferase expression levels were measured to determine longevity of the expression.

Results: Significantly high luciferase expression levels were observed in cultured RENCA, TCMK-1, and HEK293 cells over 1 month compared with controls (non-integrase system). The luciferase cDNA sequence was integrated at a pseudo attP site termed mpsL1. In vivo luciferase expression levels in the integrase group were sustained and significantly higher than those in the control group over 2 months. Furthermore, ?C31 integrase-transfected cells had less genomic DNA damage caused by integrase expression.

Discussion and conclusion: These results demonstrated that the ?C31 integrase system could produce long-term (2 months) in vivo gene expression in mouse kidney.  相似文献   
10.
目的: 探讨应用超声靶向破坏微泡 (UTMD) 技术介导小鼠肝癌细胞株JNK1基因的表达、细胞迁移和侵袭抑制的作用,阐明其作用机制。方法: 构建并筛选RNA干扰效果最好的短发夹RNA(shRNA)。将小鼠肝癌细胞株Hca-F分为正常Hca-F细胞组、shRNA质粒组、脂质体组、超声微泡结合超声辐照组及脂质体结合超声微泡加超声辐照组。采用倒置荧光显微镜观察各组细胞转染率,荧光定量PCR和Western blotting 法检测JNK1基因mRNA和蛋白表达水平,CCK-8法检测各组细胞的细胞活性,应用Transwell 实验检测各组细胞的体外迁移能力。结果: 脂质体结合超声微泡加超声辐照组细胞转染率高于shRNA质粒组、脂质体组和超声微泡结合超声辐照组(均P<0.05),脂质体组和超声微泡结合超声辐照组比较差异无统计学意义(P>0.05)。脂质体结合超声微泡加超声辐照组JNK1 mRNA和蛋白表达水平低于其他各组(P<0.05);脂质体结合超声微泡加超声辐照组细胞活性和平均穿膜细胞数均低于其他各组(P<0.05)。结论: UTMD技术结合脂质体转染法可以提高小鼠肝癌细胞株JNK1 shRNA的转染效率,增强其对基因表达、细胞活力、迁移和侵袭能力的抑制。  相似文献   
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