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71.
A new amdoparvovirus, named raccoon dog and fox amdoparvovirus (RFAV), was identified in farmed sick raccoon dogs and arctic foxes. Phylogenetic analyses showed that RFAV belongs to a new species within the genus Amdoparvovirus of the family Parvoviridae. An RFAV strain was isolated in Crandell feline kidney cell culture.  相似文献   
72.
医用电子仪器专业是一门新兴的交叉边沿性学科,分析近年来医电专业开设过程中所存在的问题.并对解决方案进行了探讨。  相似文献   
73.
Circular RNA (circRNA) participates in a variety of pathophysiological processes, including the development of gastric cancer (GC). However, the role of circ_0006089 in GC progression and its underlying molecular mechanism need to be further revealed. Quantitative real‐time PCR was utilized for detecting circ_0006089, microRNA (miR)‐361‐3p and transforming growth factor‐β1 (TGFB1) expression. The interaction between miR‐361‐3p and circ_0006089 or TGFB1 was confirmed using a dual‐luciferase reporter assay and an RNA immunoprecipitation (RIP) assay. Cell proliferation, metastasis, apoptosis, and angiogenesis were determined using colony formation assay, EdU assay, transwell assay, flow cytometry, and tube formation assay. Cell glycolysis was evaluated by detecting glucose consumption, lactate production, and ATP levels. In addition, western blot (WB) analysis was used to measure protein expression. Xenograft tumor models were used to assess the effect of circ_0006089 knockdown on GC tumorigenesis. circ_0006089 had been found to be upregulated in GC tissues and cells, and it could act as an miR‐361‐3p sponge. circ_0006089 knockdown suppressed GC proliferation, metastasis, glycolysis, angiogenesis, and increased apoptosis, while this effect could be revoked by miR‐361‐3p inhibitor. TGFB1 was targeted by miR‐361‐3p, and its overexpression reversed the effects of miR‐361‐3p on GC cell function. Also, circ_0006089 promoted TGFB1 expression via sponging miR‐361‐3p. Animal experiments showed that silenced circ_0006089 inhibited GC tumorigenesis through the miR‐361‐3p/TGFB1 pathway. Our results revealed that the circ_0006089/miR‐361‐3p/TGFB1 axis contributed to GC progression, confirming that circ_0006089 might be a potential therapeutic target for GC.  相似文献   
74.
原发性肝癌Twist基因表达的研究   总被引:7,自引:3,他引:4  
目的:研究Twist基因在人原发性肝癌(primary liver cancer,PLC)组织中的表达及其临床意义。方法:应用免疫组织化学SABC染色方法检测45例PLC组织及癌旁组织中Twist蛋白并采用RT-PCR对TwistmR-NA的表达进行分析研究。结果:PLC组织、癌旁组织及正常肝组织中Twist的阳性表达率分别为80.0%、57.8%和22.2%。PLC和癌旁组织与正常对照肝组织中Twist的表达相比较差异均有统计学意义,P〈0.05。肿瘤包膜也可见Twist表达。RT-PCR检测Twist结果显示,PLC组织中Twist mRNA表达显著上调。结论:PLC组织中高表达转录因子Twist对肿瘤的发生、发展起着重要作用。  相似文献   
75.
76.
The processes of cancer initiation, progression, and response to therapy are affected by the sex of cancer patients. Immunotherapy responses largely depend on the tumor microenvironment (TME), but how sex may shape some TME features, remains unknown. Here, we analyzed immune infiltration signatures across 19 cancer types from 1771 male and 1137 female patients in The Cancer Genome Atlas to evaluate how sex may affect the tumor mutational burden (TMB), immune scores, stromal scores, tumor purity, immune cells, immune checkpoint genes, and functional pathways in the TME. Pan‐cancer analyses showed higher TMB and tumor purity scores, as well as lower immune and stromal scores in male patients as compared to female patients. Lung adenocarcinoma, lung squamous carcinoma, kidney papillary carcinoma, and head and neck squamous carcinoma showed the most significant sex biases in terms of infiltrating immune cells, immune checkpoint gene expression, and functional pathways. We further focused on lung adenocarcinoma samples in order to identify and validate sex‐specific immune cell biomarkers with prognostic potential. Overall, sex may affect the tumor microenvironment, and sex‐specific TME biomarkers may help tailor cancer immunotherapy in certain cancer types.  相似文献   
77.
南京鼓楼医院脊柱外科于2002年建立并开始应用脊柱外科手术患者临床数据库系统.文章回顾总结脊柱外科手术患者临床数据库系统的应用体会,供参考.  相似文献   
78.
Aims/IntroductionOverweight and obesity in adults are strongly associated with an increased risk of prediabetes, and this study set out to gain a better understanding of the optimal body mass index (BMI) range for assessing the risk of prediabetes in the Chinese population.Materials and MethodsThe cohort study included 100,309 Chinese adults who underwent health screening. Participants were divided into six groups based on the cut‐off point for BMI recommended by the World Health Organization (underweight: <18.5 kg/m2, normal‐weight: 18.5–24.9 kg/m2, pre‐obese: 25.0–29.9 kg/m2, obese class I: 30.0–34.9 kg/m2, obese class II: 35.0–39.9 kg/m2, and obese class III ≥40 kg/m2). The association of BMI with prediabetes and the shape of the correlation were modeled using multivariate Cox regression and restricted cubic spline regression, respectively.ResultsIn the multivariate Cox regression model, with normal weight as the control group, underweight people had a lower risk of developing prediabetes, whereas obese and pre‐obese people had a higher risk of prediabetes. Additionally, in the restricted cubic spline model, we found that the association of BMI with prediabetes follows a positive dose–response relationship, but does not conform to the pattern of obesity paradox. Among the general population in China, a BMI of 23.03 kg/m2 might be a potential intervention threshold for prediabetes.ConclusionsThe national cohort study found that the association of BMI with prediabetes follows a positive dose–response relationship, rather than a pattern of obesity paradox. For Chinese people with normal weight, more attention should be paid to glucose metabolism when BMI exceeds 23.03 kg/m2.  相似文献   
79.
Glioblastoma multiform (GBM) is a highly aggressive primary brain tumor. Exosomes derived from glioma cells under a hypoxic microenvironment play an important role in tumor biology including metastasis, angiogenesis and chemoresistance. However, the underlying mechanisms remain to be elucidated. In this study, we aimed to explore the role of connexin 43 on exosomal uptake and angiogenesis in glioma under hypoxia. U251 cells were exposed to 3% oxygen to achieve hypoxia, and the expression levels of HIF-1α and Cx43, involved in the colony formation and proliferation of cells were assessed. Exosomes were isolated by differential velocity centrifugation from U251 cells under normoxia and hypoxia (Nor-Exos and Hypo-Exos), respectively. Immunofluorescence staining, along with assays for CCK-8, tube formation and wound healing along with a transwell assay were conducted to profile exosomal uptake, proliferation, tube formation, migration and invasion of HUVECs, respectively. Our results revealed that Hypoxia significantly up-regulated the expression of HIF-1α in U251 cells as well as promoting proliferation and colony number. Hypoxia also increased the level of Cx43 in U251 cells and in the exosomes secreted. The uptake of Dio-stained Hypo-Exos by HUVECs was greater than that of Nor-Exos, and inhibition of Cx43 by 37,43gap27 or lenti-Cx43-shRNA efficiently prevented the uptake of Hypo-Exos by recipient endothelial cells. In addition, the proliferation and total loops of HUVECs were remarkably increased at 24 h, 48 h, and 10 h after Hypo-Exos, respectively. Notably, 37,43gap27, a specific Cx-mimetic peptide blocker of Cx37 and Cx43, efficiently alleviated Hypo-Exos-induced proliferation and tube formation by HUVECs. Finally, 37,43gap27 also significantly attenuated Hypo-Exos-induced migration and invasion of HUVECs. These findings demonstrate that exosomal Cx43 contributes to glioma angiogenesis mediated by Hypo-Exos, and suggests that exosomal Cx43 might serve as a potential therapeutic target for glioblastoma.  相似文献   
80.
Transporters are traditionally considered to transport small molecules rather than large-sized nanoparticles due to their small pores. In this study, we demonstrate that the upregulated intestinal transporter (PCFT), which reaches a maximum of 12.3-fold expression in the intestinal epithelial cells of diabetic rats, mediates the uptake of the folic acid-grafted nanoparticles (FNP). Specifically, the upregulated PCFT could exert its function to mediate the endocytosis of FNP and efficiently stimulate the traverse of FNP across enterocytes by the lysosome-evading pathway, Golgi-targeting pathway and basolateral exocytosis, featuring a high oral insulin bioavailability of 14.4% in the diabetic rats. Conversely, in cells with relatively low PCFT expression, the positive surface charge contributes to the cellular uptake of FNP, and FNP are mainly degraded in the lysosomes. Overall, we emphasize that the upregulated intestinal transporters could direct the uptake of ligand-modified nanoparticles by mediating the endocytosis and intracellular trafficking of ligand-modified nanoparticles via the transporter-mediated pathway. This study may also theoretically provide insightful guidelines for the rational design of transporter-targeted nanoparticles to achieve efficient drug delivery in diverse diseases.  相似文献   
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