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31.
曾艾  张琴  刘炜  何梅  王聪 《现代生物医学进展》2019,19(11):2144-2147
目的:探讨超声联合钼靶X线对直径小于1 cm的乳腺癌诊断价值。方法:选择我院2012年1月至2017年12月收治的66例乳腺疾病患者,所有患者术前均经钼靶X线及彩色多普勒超声检查,分析其病理结果,分析钼靶X线、彩色多普勒超声及二者联合对乳腺肿块的检查结果(边缘毛刺征、血管、淋巴结、微小钙化),比较其对乳腺癌的灵敏度、特异度、准确度、阳性预测值及阴性预测值。结果:66例患者中,经病理检查发现恶性肿瘤34例,良性肿瘤32例。与病理检测相比,彩色多普勒超声联合钼靶X线对乳腺肿块的良恶性检出率无差异性(P0.05),而彩色多普勒超声,钼靶X线的良恶性检出率均显著降低(P0.05)。彩色多普勒超声与钼靶X线良恶性检出率对比无差异(P0.05),但均低于彩色多普勒超声联合钼靶X线的检出率(P0.05)。彩色多普勒超声与钼靶X线对乳腺癌的边缘毛刺征的检出率对比无统计学意义(P0.05);彩色多普勒超声对血管和淋巴结的检出率明显高于钼靶X线,而微小钙化的检出率明显低于钼靶X线,对比差异有统计学意义(P0.05)。彩色多普勒超声联合钼靶X线的灵敏度、特异度、准确度、阳性预测值及阴性预测值均明显高于彩色多普勒超声及钼靶X线(P0.05),钼靶X线及彩色多普勒超声间对比无统计学意义(P0.05)。结论:彩色多普勒超声与钼靶X线对直径小于1 cm乳腺癌的诊断各有优势,二者联合应用的诊断价值优于单一诊断方法。  相似文献   
32.
目的:探讨超声内镜(EUS)辅助下内镜黏膜下切除术(EMR)对食管癌前病变患者肿瘤标志物及应激反应指标的影响。方法:选择山东大学齐鲁医院青岛院区消化内科于2016年3月至2018年4月期间收治的食管癌前病变患者137例,采用随机数字表法将患者分为常规组(n=68,常规胃镜下行EMR)和EUS组(n=69,EUS辅助下行EMR),比较两组患者临床指标,比较两组术前、术后血清肿瘤标志物及应激反应指标水平,比较两组术前、术后1周相关遗传学分子水平。结果:EUS组手术时间、术后流质饮食时间均短于常规组(P0.05),并发食管黏膜小穿孔例数、使用钛夹止血例数均少于常规组(P0.05)。两组患者术后肿瘤特异性生长因子(TSGF)、细胞角蛋白19血清片段21-1(CYFRA21-1)、鳞状上皮细胞癌抗原(SCC-Ag)均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后肾上腺素(E)、去甲肾上腺素(NE)、肾素(R)、血管紧张素Ⅱ(AngⅡ)、醛固酮均较术前升高,但EUS组低于常规组(P0.05)。两组患者术后1周细胞周期素E(Cyclin E)、转化生长因子-α(TGF-α)均较术前降低,且EUS组低于常规组(P0.05)。结论:相比于常规胃镜,经EUS辅助下EMR治疗食管癌前病变可有效改善患者的临床指标,减轻患者应激反应,有利于降低血清肿瘤标志物及遗传学分子水平。  相似文献   
33.
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Highlights
  • •AP-DIA/SWATH analysis to identify TCTP-interacting proteins in NF1 tumor cells.
  • •A highly specific TCTPEF1A2 interaction but rather than TCTPEF1A1 interaction.
  • •TCTPEF1A2 interaction mediating formation of EF1A2-elogation factor complex.
  • •TCTPEF1A2 dependent translation machinery regulating NF1 tumor cell growth.
  相似文献   
34.
During the last four decades, nuclear medicine has undergone enormous growth, and positron emission tomography (PET) has been in the driving seat for most of the time. 18F-fluorodeoxyglucose (18F-FDG) is the most widely used agent for the detection of hibernating myocardium and metabolically active cancer tissue. But its cost and limited availability are the main limitations. For a long time different researchers and groups of pharmacists have tried to label glucose with a cheaper and long-acting radionuclide like 99mTc. However, they failed to achieve this goal owing to the chemical complexity of 99mTc and the lack of maintaining the physiological activity of diagnostic compounds. A pre-targeting strategy based on strain-promoted [3 + 2] azide-alkyne cycloaddition (SPAAC) reaction was applied to solve this problem. Functional click synthons were synthesized: 2-azido-2-deoxy-d-glucose (GlucN3) as a glucose analogue, and N- (2- (2- (2- (bis (pyridin-2-ylmethyl) amino) ethoxy) ethoxy) ethyl-2- (6H-11,12-didehydrodibenzo [a,e] cycloocten-5-ylideneaminooxy) acetamide (C7) as a 99mTc(CO)3 labeling and azido-binding group. The results of biodistribution experiments in mice bearing S180 tumor show the relatively high tumor/blood ratio (up to 2.95) and tumor/muscle ratio (up to 6.37), and both of them decreases significantly in the glucose blocking experiment. It indicates that GlucN3 behaves similarly to glucose and that in vivo SPAAC reactions can occur effectively. It is supposed that this pre-targeting strategy can indeed enhance target specificity and may be used for glucose metabolism imaging in tumor diagnosis.  相似文献   
35.
The development of alternative therapeutic strategies to tumor necrosis factor (TNF)-blocking antibodies for the treatment of inflammatory diseases has generated increasing interest. In particular, selective inhibition of TNF receptor 1 (TNFR1) promises a more precise intervention, tackling only the pro-inflammatory responses mediated by TNF while leaving regenerative and pro-survival signals transduced by TNFR2 untouched. We recently generated a monovalent anti-TNFR1 antibody fragment (Fab 13.7) as an efficient inhibitor of TNFR1. To improve the pharmacokinetic properties of Fab 13.7, the variable domains of the heavy and light chains were fused to the N-termini of newly generated heterodimerizing Fc chains. This novel Fc heterodimerization technology, designated “Fc-one/kappa” (Fc1κ) is based on interspersed constant Ig domains substituting the CH3 domains of a γ1 Fc. The interspersed immunoglobulin (Ig) domains originate from the per se heterodimerizing constant CH1 and CLκ domains and contain sequence stretches of an IgG1 CH3 domain, destined to enable interaction with the neonatal Fc receptor, and thus promote extended serum half-life. The resulting monovalent Fv-Fc1κ fusion protein (Atrosimab) retained strong binding to TNFR1 as determined by enzyme-linked immunosorbent assay and quartz crystal microbalance, and potently inhibited TNF-induced activation of TNFR1. Atrosimab lacks agonistic activity for TNFR1 on its own and in the presence of anti-human IgG antibodies and displays clearly improved pharmacokinetic properties.  相似文献   
36.
《遗传学报》2022,49(10):913-926
Ferroptosis has emerged as a crucial regulated cell death involved in a variety of physiological processes or pathological diseases, such as tumor suppression. Though initially being found from anticancer drug screening and considered not essential as apoptosis for growth and development, numerous studies have demonstrated that ferroptosis is tightly regulated by key genetic pathways and/or genes, including several tumor suppressors and oncogenes. In this review, we introduce the basic concepts of ferroptosis, characterized by the features of non-apoptotic, iron-dependent, and overwhelmed accumulation of lipid peroxides, and the underlying regulated circuits are considered to be pro-ferroptotic pathways. Then, we discuss several established lipid peroxidation defending systems within cells, including SLC7A11/GPX4, FSP1/CoQ, GCH1/BH4, and mitochondria DHODH/CoQ, all of which serve as anti-ferroptotic pathways to prevent ferroptosis. Moreover, we provide a comprehensive summary of the genetic regulation of ferroptosis via targeting the above-mentioned pro-ferroptotic or anti-ferroptotic pathways. The regulation of pro- and anti-ferroptotic pathways gives rise to more specific responses to the tumor cells in a context-dependent manner, highlighting the unceasing study and deeper understanding of mechanistic regulation of ferroptosis for the purpose of applying ferroptosis induction in cancer therapy.  相似文献   
37.
BackgroundComparative effectiveness studies of cancer therapeutics in observational data face confounding by patterns of clinical treatment over time. The validity of survival analysis in longitudinal health records depends on study design choices including index date definition and model specification for covariate adjustment.MethodsOverall survival in cancer is a multi-state transition process with mortality and treatment switching as competing risks. Parametric Weibull regression quantifies proportionality of hazards across lines of therapy in real-world cohorts of 12 solid tumor types. Study design assessments compare alternative analytic models in simulations with realistic disproportionality. The multi-state simulation framework is adaptable to alternative treatment effect profiles and exposure patterns.ResultsEvent-specific hazards of treatment-switching and death are not proportional across lines of therapy in 12 solid tumor types. Study designs that include all eligible lines of therapy per subject showed lower bias and variance than designs that select one line per subject. Confounding by line number was effectively mitigated across a range of simulation scenarios by Cox proportional hazards models with stratified baseline hazards and inverse probability of treatment weighting.ConclusionQuantitative study design assessment can inform the planning of observational research in clinical oncology by demonstrating the potential impact of model misspecification. Use of empirical parameter estimates in simulation designs adapts analytic recommendations to the clinical population of interest.  相似文献   
38.
目的:探究重症肺炎患者干扰素-r、白细胞介素-6 和肿瘤坏死因子-alpha含量变化及其临床意义。方法:选取我院收治并确诊 为肺炎的患者103 例,根据病情不同,将其分为重症肺炎组52 例及普通肺炎组51 例,同时选取同期参加健康体检人群50 例,为 对照组。比较三组成员不同时间段干扰素-r、白细胞介素-6 和肿瘤坏死因子-alpha含量,重症肺炎组患者存活与死亡组上述因子含 量情况。结果:入院6 h 后,与对照组比较,重症肺炎及普通肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-琢含量较高P< 0.05,与普通肺炎组比较,重症肺炎组重症肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P<0.05;入院24 h后,与 对照组比较,重症肺炎组干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P<0.05,普通肺炎组与对照组比较无差异P> 0.05;重症肺炎死亡组患者干扰素-r、白细胞介素-6 及肿瘤坏子因子-alpha含量较高P<0.05。结论:干扰素-r、白细胞介素-6 以及 肿瘤坏死因子-alpha参与患者的免疫调节,可间接提示患者的病程发展,可作为判断病情程度的有利依据。  相似文献   
39.
哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,m TOR)在肿瘤的发生、侵袭、转移,甚至肿瘤的局部复发都起着重要的作用。头颈肿瘤作为全球最常见的癌症死亡原因之一,有多元的逐步恶化的过程。近年来研究表明m TOR信号通路的异常表达是头颈肿瘤最常见的病理改变之一,且m TOR信号通路的多种组成元件与头颈肿瘤患者的预后有明显的相关性,这不仅可为头颈肿瘤的特异性靶向治疗提供依据,而且也可为预测头颈肿瘤患者的预后提供参考。本文就m TOR信号通路及其在头颈肿瘤中的作用做一综述,旨在对m TOR信号通路和头颈肿瘤及其预后的关系有更进一步的认识。  相似文献   
40.
目的:口腔鳞状细胞癌是一类极易发生局部侵袭和淋巴结转移的恶性肿瘤,CD9蛋白在多种肿瘤的发生发展及侵袭转移过程中起到重要作用,本研究旨在分析CD9蛋白在口腔鳞状细胞癌中的表达水平及其临床意义。方法:收集我院诊断明确的口腔鳞癌肿瘤患者石蜡标本合计80例,通过免疫组化手段对CD9蛋白表达水平进行评价,并根据CD9蛋白的表达水平分组,分析患者的临床病理学特征与CD9蛋白的关系。结果:CD9在正常组织和癌旁组织正常表达,在肿瘤组织中表达率低,其表达水平和口腔鳞癌的分化程度,淋巴结转移及最终分期有相关性(P0.05)。结论:本研究结果揭示,CD9在口腔鳞状细胞癌的发生发展中起到重要作用,CD9蛋白水平的低表达或不表达可能预测着肿瘤具有更明显的恶性生物学行为,并可能成为口腔鳞状细胞癌预后的生物学指标及基因治疗的新靶点。  相似文献   
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