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101.
Stainless steel wear debris of a scoliotic growth guidance system has little local and systemic effect in an animal model 下载免费PDF全文
102.
昼夜节律是生命体为适应自然环境而产生的一种生物特性,生物钟基因调节着生命体的节律,Bmal1、Clock、PERs、CRYs、Rev-erbα等生物钟基因及下游的钟控基因发挥了重要作用。免疫细胞与骨细胞之间通过共同的细胞因子和信号通路相互作用,调节骨代谢平衡,免疫紊乱会导致骨代谢异常。骨免疫学的诞生有利于深入研究骨骼系统与免疫系统的相互作用,骨免疫参与了许多骨科疾病和免疫性疾病的发生和进展。生理状态下,生物钟基因通过调控骨骼系统与免疫系统的生物节律,在维持骨免疫的平衡状态中发挥着重要作用。病理状态下,生物钟基因功能异常不但导致骨骼系统和免疫系统的节律紊乱,进一步导致骨量丢失和免疫炎症反应,而且通过IL-1、IL-6、TNF-α、RANKL等骨免疫因子对骨代谢产生作用。反过来,免疫炎症反应也会对生物钟基因正常功能产生影响,进而影响骨代谢。根据生物钟基因和骨代谢自身的特点,认识生理病理状态下生物钟基因与骨免疫的相互作用,对骨骼系统疾病和免疫系统疾病的防治有一定的指导意义。 相似文献
103.
J. Hu X. Feng M. Valdearcos D. Lutrin Y. Uchida S.K. Koliwad M. Maze 《British journal of anaesthesia》2018,120(3):537-545
Background
Perioperative neurocognitive disorders (PND) result in long-term morbidity and mortality with no effective interventions available. Because interleukin-6 (IL-6), a pro-inflammatory cytokine, is consistently up-regulated by trauma, including after surgery, we determined whether IL-6 is a putative therapeutic target for PND in a mouse model.Methods
Following institutional approval, adult (12–14 weeks) male C57/Bl6 mice were pretreated with the IL-6 receptor (IL6R) blocking antibody tocilizumab prior to open tibia fracture with internal fixation under isoflurane anaesthesia. Inflammatory and behavioural responses in a trace fear conditioning (TFC) paradigm were assessed postoperatively. Separately, the effects of IL-6 administration or of depletion of bone marrow-derived monocytes (BM-DMs) with clodrolip on the inflammatory and behavioural responses were assessed. Blood brain barrier disruption, hippocampal microglial activation, and infiltration of BM-DMs were each assessed following IL-6 administration.Results
The surgery-induced decrement in freezing time in the TFC assay, indicative of cognitive decline, was attenuated by tocilizumab (P<0.01). The surgery-induced increase in pro-inflammatory mediators was significantly reduced by tocilizumab. Exogenously administered IL-6 significantly impaired freezing behaviour (P<0.05) and up-regulated pro-inflammatory cytokines; both responses were prevented by depletion of BM-DMs. IL-6 disrupted the blood brain barrier, and increased hippocampal activation of microglia and infiltration of BM-DMs.Conclusions
IL-6 is both necessary and sufficient to produce cognitive decline. Following further preclinical testing of its perioperative safety, the IL6R blocker tocilizumab is a candidate for prevention and/or treatment of PND. 相似文献104.
Porcine IL‐6, IL‐1β, and TNF‐α regulate the expression of pro‐inflammatory‐related genes and tissue factor in human umbilical vein endothelial cells 下载免费PDF全文
Hanchao Gao Qing Zhang Jicheng Chen David K.C. Cooper Hidetaka Hara Pengfei Chen Ling Wei Yanli Zhao Jia Xu Zesong Li Zhiming Cai Shaodong Luan Lisha Mou 《Xenotransplantation》2018,25(5)
Whether porcine cytokines are induced after pig‐to‐primate xenotransplantation and activate human cells remains unknown. First, we investigated the regulation of porcine IL‐6, IFN‐γ, IL‐1β, and TNF‐α in xenotransplantation using an in vitro model in which porcine aortic endothelial cells (PAECs) and porcine peripheral blood mononuclear cells (PBMCs) were stimulated with human serum. Downstream cytokines/chemokines were monitored. Pro‐inflammatory cytokines (IL‐6, IFN‐γ, and IL‐1β) and chemokines (IL‐8, MCP‐1, and CXCL2) were upregulated in the both cell types. TNF‐α was induced 10‐fold in PAECs, but not in PBMCs. Then, we assessed the role of porcine IL‐6, IFN‐γ, IL‐1β, and TNF‐α in xenotransplantation using western blotting and real‐time PCR. Human umbilical vein endothelial cells (HUVECs) were selected as the target cells. Signaling pathways and downstream genes, such as those related to adhesion, inflammation, and coagulation, and chemokines were investigated. Porcine IL‐1β and TNF‐α significantly activated NF‐κB and P38, and STAT3 was activated by porcine IL‐6 in HUVECs. The adhesion genes (E‐selectin, VCAM‐1, and ICAM‐1), inflammatory cytokines (IL‐6, IL‐1β, and TNF‐α), chemokines (MCP‐1 and IL‐8), and the pro‐coagulation gene (tissue factor) were upregulated by porcine IL‐1β and TNF‐α. Porcine IL‐6 increased the expression of ICAM‐1, IL‐6, MCP‐1, and tissue factor, but decreased IL‐8 expression slightly. Surprisingly, porcine IFN‐γ could not activate STAT1 or regulate the expression of any of the above genes in HUVECs. In conclusion, these findings suggest that porcine IL‐6, IL‐1β, and TNF‐α activate HUVECs and regulate downstream genes expression, which may promote inflammation and coagulation response after xenotransplantation. 相似文献
105.
目的探讨米诺环素预处理对老年大鼠吸入异氟醚后认知功能和海马炎症反应的影响。方法健康雄性SPF级SD大鼠48只,约20月龄,体重350~400g,随机分为3组:生理盐水组(NS组)、异氟醚组(Iso组)、米诺环素预给药组(M组),每组16只。NS组腹腔注射等容量生理盐水;Iso组大鼠开始吸入2.5%异氟醚3min,随后1.5%异氟醚麻醉维持4h;M组于吸入异氟醚前30min腹腔注射米诺环素50mg/kg,余同Iso组。所有大鼠麻醉结束后24h立即进行认知功能测试,包括Morris水迷宫和旷场实验测试,认知功能测试完毕后立即处死大鼠,取海马组织,采用ELISA法测定大鼠海马IL-1、IL-6、TNF-α的浓度。结果与NS组比较,Iso组第2、3和4天逃避潜伏期明显延长(P0.05),第5天平台象限停留时间明显缩短、穿越平台象限次数明显减少(P0.05),第1、2和3天中心区停留时间明显缩短(P0.05)。与Iso组比较,M组第2、3和4天逃避潜伏期明显缩短(P0.05),第5天平台象限停留时间明显延长、穿越平台象限次数明显增多(P0.05),第1、2和3天中心区停留时间明显延长(P0.05)。与NS组比较,Iso组海马IL-1、IL-6、TNF-α浓度明显升高(P0.05),与Iso组比较,M组海马IL-1、IL-6、TNF-α浓度明显降低(P0.05)。NS组和M组不同时点各指标差异无统计学意义。结论米诺环素预处理可减轻异氟醚麻醉所致老年大鼠认知功能障碍,其机制可能与抑制海马炎症反应有关。 相似文献
106.
Aim To explore the mechanism of grape seed proanthocyanidins (GSPs) targeting astrocytes (AS), so as to regulate the phenotype and function of AS and maximize their neuroprotective effect. Methods The effects of GSPs on the phenotype, secretion of pro-inflammatory factors and neurotrophic factors of Al AS induced by TNF-α, IL-1α and Clq were investigated by RT-PCR, Elisa and Western blot in vitro. And JNK phosphorylation was determined using Western blot. Results GSPs significantly reduced the expression of C3d and Clq of Al AS markers and inhibited the phosphorylation of JNK. Moreover, compared with the model group, GSPs could significantly inhibit the release of pro-inflammatory cytokines IL-6, IL-1 α, IL-17 and H 2 O 2, and promote the secretion of anti-inflammatory cytokine TGF-β and neurotrophic factor CNTF. Conclusions GSPs can inhibit the polarization of AS to Al and improve the inflammatory micro-environment, which are related to the inhibition of JNK phosphorylation. © 2023 Publication Centre of Anhui Medical University. All rights reserved. 相似文献
107.
108.
T. Ris A. Teixeira-Carvalho R. Matos Pinto Coelho C. Brandao-de-Resende M. Souza Gomes L. Rodrigues Amaral P. H. Oliveira Murta Pinto L. J. Souza Santos J. Teixeira Salles Jolien Roos-Hesselink N. Verkaik T. Cristina Abreu Ferrari M. C. Pereira Nunes 《Clinical and experimental immunology》2019,196(3):374-382
Infective endocarditis (IE) is the cardiac disease with the highest rates of mortality. New biomarkers that are able to identify patients at risk for death are required to improve patient management and outcome. This study aims to investigate if cytokines, chemokines and growth factors measured at IE diagnosis can predict mortality. Patients with definite IE, according to the Duke’s modified criteria, were included. Using high-performance Luminex assay, 27 different cytokines, chemokines and growth factors were analyzed. Machine learning techniques were used for the prediction of death and subsequently creating a decision tree, in which the cytokines, chemokines and growth factors were analyzed together with C-reactive protein (CRP). Sixty-nine patients were included, 41 (59%) male, median age 54 [interquartile range (IQR) = 41–65 years] and median time between onset of the symptoms and diagnosis was 12 days (IQR = 5–30 days). The in-hospital mortality was 26% (n = 18). Proinflammatory cytokines interkeukin (IL)-15 and C-C motif chemokine ligand (CCL4) were found to predict death, adding value to CRP levels. The decision tree predicted correctly the outcome of 91% of the patients at hospital admission. The high-risk group, defined as CRP ≥ 72 mg/dL, IL-15 ≥ 5·6 fg/ml and CCL4 ≥ 6·35 fg/ml had an 88% in-hospital mortality rate, whereas the patients classified as low-risk had a mortality rate of 8% (P = < 0·001). Cytokines IL-15 and CCL4 were predictors of mortality in IE, adding prognostic value beyond that provided by CRP levels. Assessment of cytokines has potential value for clinical risk stratification and monitoring in IE patients. 相似文献
109.
W. Lu Y. Wang Q. Zhang S. Owen M. Green T. Ni M. Edwards Y. Li L. Zhang A. Harris J-L. Li D. G. Jackson S. Jiang 《Clinical and experimental immunology》2019,198(2):198-211
Tumour necrosis factor (TNF) is a multi-functional cytokine with profound and diverse effects on physiology and pathology. Identifying the molecular determinants underlying the functions and pathogenic effects of TNF is key to understanding its mechanisms of action and identifying new therapeutic opportunities based on this important molecule. Previously, we showed that some evolutionarily conserved peptides derived from TNF could induce cell death (e.g. apoptosis and/or necrosis), a feature of immune defence mechanisms shared by many vertebrates. In this study, we demonstrated that necrosis-inducing peptide P16 kills human glioblastoma cancer cells and primary human hepatoma or renal cancer cells isolated from patients who had not responded to standard treatments. Importantly, we show that the necrosis-inducing peptide P1516 significantly improves survival by inhibiting tumour metastasis in a 4T1 breast cancer syngeneic graft mouse model. Because the lymphatic system is an important metastatic route in many cancers, we also tested the effect of TNF-derived peptides on monolayers of primary human lymphatic endothelial cells (hDLEC) and found that they increased junctional permeability by inducing cytoskeletal reorganization, gap junction formation and cell death. Transmission electron microscopy imaging evidence, structural analysis and in-vitro liposome leakage experiments strongly suggest that this killing is due to the cytolytic nature of these peptides. P1516 provides another example of a pro-cytotoxic TNF peptide that probably functions as a cryptic necrotic factor released by TNF degradation. Its ability to inhibit tumour metastasis and improve survival may form the basis of a novel approach to cancer therapy. 相似文献
110.
Monique Garcia Alana Santos‐Dias Andr Luis Lacerda Bachi Manoel Carneiro Oliveira‐Junior Adilson Santos Andrade‐Souza Srgio Csar Ferreira Jefferson Comin Jonco Aquino‐Junior Francine Maria Almeida Nicole Cristine Rigonato‐Oliveira Ana Paula Ligeiro Oliveira Luiz Eduardo Baggio Savio Robson Coutinho‐Silva Tobias Müller Marco Idzko Timo Siepmann Rodolfo Paula Vieira 《European journal of immunology》2019,49(6):928-939
Creatine (Cr) is a substrate for adenosine triphosphate synthesis, and it is the most used dietary supplement among professional and recreative athletes and sportsmen. Creatine supplementation may increase allergic airway response, but the cellular and molecular mechanisms are unknown. We used murine model of OVA‐induced chronic asthma and showed that Cr supplementation increased total proteins, ATP level, lymphocytes, macrophages, and IL‐5 levels in BALF, as well as IL‐5 in the supernatant of re‐stimulated mediastinal lymph nodes. IL‐5 and IL‐13 expression by epithelial cells and by peribronchial leukocytes were increased by Cr. Cr augmented the expression of P2 × 7 receptor by peribronchial leukocytes and by epithelial cells, and increased the accumulation of eosinophils in peribronchial space and of collagen fibers in airway wall. In human cells, while Cr induced a release of ATP, IL‐6, and IL‐8 from BEAS‐2B cells, whole blood cells, such as eosinophils, and CD4+ T cells, P2 × 7 receptor inhibitor (A740003) reduced such effects, as denoted by reduced levels of ATP, IL‐6, and IL‐8. Therefore, Cr supplementation worsened asthma pathology due to activation of airway epithelial cells and peribronchial leukocytes, involving purinergic signaling. 相似文献