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991.
Endothelial cells (ECs) released microvesicles (EMVs) could modulate the functions of target cells by transferring their microRNAs (miRs). We have reported that miR-125a-5p protected EC function. In this study, we determined whether EMVs provided beneficial effects on ECs by transferring miR-125a-5p. Human brain microvessel ECs were transfected with miR-125a-5p mimic or miR-125a-5p short hairpin RNA to obtain miR-125a-5p overexpressing ECs and miR-125a-5p knockdown ECs, and their derived EMVs. For the functional study, ECs or hypoxia/reoxygenation injured ECs were coincubated with various EMVs. The survival and angiogenic function of ECs were measured. Western blot and quantitative real time polymerase chain reaction (qRT-PCR) were used for measuring the levels of phosphoinositide 3-kinase (PI3K), phosphorylation-Akt (p-Akt)/Akt, p-endothelial nitric oxide synthase (p-eNOS), cleaved caspase-3, and miR-125a-5p. PI3K inhibitor was used for pathway analysis. EMVs promoted the proliferation, migration, and tube formation ability of ECs, and alleviated the apoptotic rate of ECs. These effects were associated by an increase in p-Akt/Akt and p-eNOS, and a decrease in cleaved caspase-3 could be abolished by LY294002. Overexpression or downregulation of miR-125a-5p in EMVs promoted or inhibited those effects of EMVs. EMVs could enhance the survival and angiogenic function of ECs via delivering miR-125a-5p to modulate the expression of PI3K/Akt/eNOS pathway and caspase-3.  相似文献   
992.
SR splicing-factors (SRSFs) play a vital role in carcinogenesis. SRSF5 was demonstrated to be upregulated in lung cancer and identified as a novel prognostic indicator for small-cell lung cancer. However, the role of SRSF5 in the pathogenesis of non–small cell lung cancer (NSCLC) and the molecular mechanism involved are still undefined. The expression of SRSF5 in NSCLC cells was detected by quantitative real-time polymerase chain reaction and Western blot analysis. The proliferation of cells was evaluated by cell counting kit-8 and BrdU assays. Apoptosis was assessed by flow cytometry and Western blot analysis of apoptosis-associated proteins including B-cell lymphoma 2 (Bcl-2), Bax, and cytochrome C (Cyt C). Glycolysis was detected by determining glucose consumption, lactate production, and pyruvate kinase M2 (PKM2) expression. We found that SRSF5 messenger RNA and protein levels were elevated in NSCLC cells. SRSF5 knockdown inhibited the proliferation and Ki67 expression in NSCLC cells. SRSF5 silencing increased the apoptotic rate, upregulated Bax and Cyt C, and decreased Bcl-2 level in NSCLC cells. Moreover, Knockdown of SRSF5 repressed glycolysis in NSCLC cells via reducing PKM2 expression. Enhanced glycolysis by PKM2 overexpression attenuated the effects of SRSF5 silencing on NSCLC cell proliferation and apoptosis. Overall, knockdown of SRSF5 inhibited proliferative ability and induced apoptosis by suppressing PKM2 expression in NSCLC cells.  相似文献   
993.
SMAD ubiquitination regulatory factor 1 (SMURF1) has been described as a tumor suppressor in multiple aggressive cancers. Nevertheless, the potential role of SMURF1 in ovarian cancer invasion and epithelial-to-mesenchymal transition (EMT) remains unclear. The aim of this study was to evaluate the efficacy of SMURF1 on tumor migration and EMT and elucidate the underlying molecular mechanism in ovarian carcinoma. We found elevated SMURF1 in several ovarian cancer cells in both messenger RNA and protein. Additionally, silencing SMURF1 apparently repressed cell proliferation and invasion capacity of SKOV3 and A2780 cells and markedly attenuated expression of linked proteins such as proliferating cellnuclear antigen, matrix metalloproteinase (MMP)-2, and MMP-9. Furthermore, depletion of SMURF1 dramatically impeded EMT progress by modulating EMT biomarkers, with a notable increase in E-cadherin expression accompanied by the decrease in N-cadherin and vimentin in both SKOV3 and A2780 cells. Interestingly, elimination of SMURF1 led to disabled homolog 2 DOC-2/DAB2 interacting protein (DAB2IP) activation and dampened AKT/Skp2 signaling. Most important, depleted of DAB2IP or treatment with the AKT agonist 740Y-P effectively abolished the suppressive effects of SMURF1 knockout on cell invasiveness and EMT process. Taken all data together, these findings demonstrated that the absence of SMURF1 repressed cell proliferation, invasive capability, and EMT process in ovarian cancer through DAB2IP/AKT/Skp2 signaling loops, suggesting that SMURF1 may serve as a new potential therapeutic agent for ovarian cancer.  相似文献   
994.
Maternal thyroid hormones (THs) have been proven crucial for embryonic development in humans, but their influence within the natural variation on wild animals remains unknown. So far the only two studies that experimentally investigated the potential fitness consequences of maternal THs in birds found inconsistent results. More studies are thus required to assess the general effects of maternal THs and their influences on more behavioral and physiological parameters. In this study, we experimentally elevated yolk TH content in a wild migratory passerine species, the collared flycatcher Ficedula albicollis, to investigate the effects on hatching success, nestling growth and oxidative stress. We found that TH‐injected eggs had a higher hatching success, and the nestlings hatched from TH‐injected eggs were heavier and larger than control nestlings, but only during the early postnatal period. These differences vanished by fledging. Nestlings from TH‐injected eggs exhibited lower activity of the glutathione‐s‐transferase, a major antioxidant enzyme, than control nestlings at day 12, a few days before fledging, but they did not differ in oxidative damage and overall intracellular oxidative state. These results suggest that the early growth‐enhancing effects incurred no observable oxidative stress. We hypothesize that such a transient growth‐enhancing effect might be adaptive in advancing the development and maturation of the offspring so they are well‐prepared in time for the upcoming migration. Further studies investigating whether such advancing effects can influence long‐term fitness, will be more than valuable.  相似文献   
995.
This paper described our efforts to develop dianilinopyrimidines as novel EGFR inhibitors. All the target compounds were tested for inhibitory effects against wild type EGFR (EGFRwt) and three tumour cells, including A549, PC-3, and HepG2. Some of the compounds performed well in antitumor activities. Especially, compound 4c 2-((2-((4-(3-fluorobenzamido)phenyl)amino)-5-(trifluoromethyl) pyrimidin-4-yl)amino)-N-methylthiophene-3-carboxamide showed higher anti-tumour activities than Gefitinib. The IC50 values of compound 4c against A549, PC-3, and HepG2. reached 0.56 μM, 2.46 μM, and 2.21 μM, respectively. In addition, further studies indicated that compound 4c could induce apoptosis against A549 cells and arrest A549 cells in the G2/M phase. Molecular docking studies showed that compound 4c could closely interact with EGFR. Generally, compound 4c was the potential for developing into an anti-tumour drug.  相似文献   
996.
Dopamine receptors are involved in several immunological diseases. We previously found that dopamine D3 receptor (D3R) on mast cells showed a high correlation with disease activity in patients with rheumatoid arthritis, but the mechanism remains largely elusive. In this study, a murine collagen-induced arthritis (CIA) model was employed in both DBA/1 mice and D3R knockout mice. Here, we revealed that D3R-deficient mice developed more severe arthritis than wild-type mice. D3R suppressed mast cell activation in vivo and in vitro via a Toll-like receptor 4 (TLR4)-dependent pathway. Importantly, D3R promoted LC3 conversion to accelerate ubiquitin-labeled TLR4 degradation. Mechanistically, D3R inhibited mTOR and AKT phosphorylation while enhancing AMPK phosphorylation in activated mast cells, which was followed by autophagy-dependent protein degradation of TLR4. In total, we found that D3R on mast cells alleviated inflammation in mouse rheumatoid arthritis through the mTOR/AKT/AMPK-LC3-ubiquitin-TLR4 signaling axis. These findings identify a protective function of D3R against excessive inflammation in mast cells, expanding significant insight into the pathogenesis of rheumatoid arthritis and providing a possible target for future treatment.Subject terms: Immunological disorders, Rheumatic diseases  相似文献   
997.
The present study was performed to explore whether and how impaired autophagy could modulate calcium/calmodulin-dependent protein kinase II (CAMKII)-regulated necrosis in the pathogenesis of acute pancreatitis (AP). Wistar rats and AR42J cells were used for AP modeling. When indicated, genetic regulation of CAMKII or ATG7 was performed prior to AP induction. AP-related necrotic injury was positively regulated by the incubation level of CAMKII. ATG7 positively modulated the level of CAMKII and necrosis following AP induction, indicating that there might be a connection between impaired autophagy and CAMKII-regulated necrosis in the pathogenesis of AP. microRNA (miR)-30b-5p was predicted and then verified as the upstream regulator of CAMKII mRNA in our setting of AP. Given that the level of miR-30b-5p was negatively correlated with the incubation levels of ATG7 after AP induction, a rescue experiment was performed and indicated that the miR-30b-5p mimic compromised ATG7 overexpression-induced upregulation of CAMKII-regulated necrosis after AP induction. In conclusion, our results indicate that ATG7-enhanced impaired autophagy exacerbates AP by promoting regulated necrosis via the miR-30b-5p/CAMKII pathway.Subject terms: Cytokines, Acute inflammation  相似文献   
998.
999.
Liver regeneration is a complicated biological process orchestrated by various liver resident cells. Hepatic cell proliferation and reconstruction of the hepatic architecture involve multiple signaling pathways. It has been reported that the Hh signal is involved in liver regeneration. However, the signal transduction pathways and cell types involved are ill studied. This study aimed to investigate hedgehog signal response cell types and the specific molecular mechanism involved in the process of liver regeneration. Partial hepatectomy (PH) of 70% was performed on ICR (Institute of Cancer Research) mice to study the process of liver regeneration. We found that the hedgehog signal was activated significantly after PH, including hedgehog ligands, receptors and intracellular signaling molecules. Ligand signals were mainly expressed in bile duct cells and non-parenchymal hepatic cells, while receptors were expressed in hepatocytes and some non-parenchymal cells. Inhibition of the hedgehog signal treated with vismodegib reduced the liver regeneration rate after partial hepatectomy, including inhibition of hepatic cell proliferation by decreasing Cyclin D expression and disturbing the cell cycle through the accumulation of Cyclin B. The current study reveals the important role of the hedgehog signal and its participation in the regulation of hepatic cell proliferation and the cell cycle during liver regeneration. It provides new insight into the recovery of the liver after liver resection.  相似文献   
1000.
Poly (ADP-ribose) polymerase (PARP) inhibitor (PARPi) resistance remains a therapeutic challenge in ovarian cancer. High-mobility group box 3 (HMGB3) plays significant roles in the development of drug resistance of many cancers. However, the function of HMGB3 in PARPi resistance is poorly understood. In the current study, we clarified that HMGB3 was aberrantly overexpressed in high-grade serous ovarian carcinoma (HGSOC) tissues, and high HMGB3 levels indicated shorter overall survival and drug resistance in HGSOC. The overexpression of HMGB3 increased the insensitivity of ovarian cancer to PARPi, whereas HMGB3 knockdown reduced PARPi resistance. Mechanistically, PARP1 was identified as a novel interaction partner of HMGB3, which could be blocked using olaparib and was enhanced upon DNA damage conditions. We further showed that loss of HMGB3 induced PARP1 trapping at DNA lesions and inhibited the PARylation activity of PARP1, resulting in an increased DNA damage response and cell apoptosis. The PARPi-resistant role of HMGB3 was also verified in a xenograft mouse model. In conclusion, HMGB3 promoted PARPi resistance via interacting with PARP1, and the targeted inhibition of HMGB3 might overcome PARPi resistance in ovarian cancer therapy.Subject terms: Chemotherapy, Ovarian cancer, Ovarian cancer, Cancer therapeutic resistance  相似文献   
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