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991.
Inflammation has been demonstrated to be the key factor for intervertebral disc degeneration (IVD), which remains a major public health problem. Isofraxidin is a coumarin compound that possesses strong anti-inflammatory activity. However, the role of isofraxidin in IVD remains unclear. The aim of this study was to evaluate the effects of isofraxidin on inflammatory response in human nucleus pulposus cells (NPCs) exposed to interleukin-1β (IL-1β). The results proved that isofraxidin attenuated the IL-1β-induced significant increases in inflammatory mediators and cytokines including nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α), and IL-6. Besides, isofraxidin also inhibited the induction effect of IL-1β on matrix metalloproteinases (MMP)-3 and MMP-13. Moreover, the NF-κB activation caused by IL-1β was significantly inhibited by isofraxidin treatment. These findings suggested that isofraxidin alleviates IL-1β-induced inflammation in NPCs. Our work provided an idea that isofraxidin might act as a novel preventive role in IVD.  相似文献   
992.
In this experiment, the cross-talk betweenNotch and the NF-κB signaling pathway was examined to reveal the mechanism of slowing down the type II collagen (ColII) and aggrecan degeneration affected by inflammatory cytokines. The expression levels of ColII and aggrecan in the intervertebral disc were observed through immunohistochemistry and hematoxylin-eosin staining+alcian blue staining, respectively. The expression levels of ColII, aggrecan, Runx2, and NF-κB in the nuclei of human nucleus pulposus cells (hNPCs) in each group, as well as the phosphorylation and acetylation levels of p65, were examined through Western blot analysis. The 293T cells were transfected with a plasmid containing the overexpressed relative domain of Notch1 intracellular domain (NICD1), and immunoprecipitation (IP) was performed to observe the combination of NICD1 and p65. HNPCs were transfected with a lentiviral-contained overexpression lacking the ANK region of NICD1, and IP was performed to observe the combination of NICD1 and p65. The expression of ColII and aggrecan in the intervertebral disc culture increased when γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-Sphenylglycine t-butyl ester (DAPT) was added to the disc culture medium. Western blot revealed that DAPT inhibited p65 phosphorylation and acetylation, and the p65 and p50 levels in the nucleus decreased. NICD1 was found to be combined with p65 in contrast to the reverse consequences after ANK domain deletion in hNPCs. In nucleus pulposus cells, the combination of p65 and the ANK domain of NICD1 is a critical procedure for the degeneration related to the NF-κB signaling pathway activation induced by IL-1β and TNF-α.  相似文献   
993.
Postoperative hepatocellular carcinoma (HCC) recurrence and metastasis throw great threaten to its overall survival (OS). This paper focus on exploring the prognostic significance of NANOG and OCT4 expression in HCC recurrence and OS after liver transplantation. Eighty-six patients who meet University of California San Francisco (UCSF) criteria and underwent liver transplantation in Tianjin First Central Hospital between August 2010 and August 2013 were included. Expression of NANOG and OCT4 was determined by immunohistochemistry. The relationships between NANOG and OCT4 expression with tumor recurrence, tumor count, histology stage, lymph node metastasis (LNM) and microvascular invasion (MVI) were explored through the χ2 test and Cox regression analysis. We found that 19/26 and 20/24 patients with positive expression of NANOG and OCT4 relapsed. Combination of NANOG and OCT4 expression was indicated as valuable prognostic signature for HCC recurrence prediction (P < 0.0011). Besides, we identified other key factors with significant correlations with recurrence, such as LNM (P = 0.011) and MVI (P = 0.024). Strikingly, recurrence sites could significantly affect recurrence time (P = 0.0062) and patients with recurrence in transplanted liver have longer recurrence time. In conclusions, we analyzed the relationships between NANOG/OCT4 expression, clinicopathology features, HCC recurrence, and OS after liver transplantation for the first time. Combination of NANOG, OCT4, LNM, histopathological stage, and MVI may be predictor for HCC recurrence posttransplantation. Comprehensive of histopathological stage grade and LNM were considered as prognosis factor for OS after liver transplantation. This should be helpful for treatment method selection for HCC patients after liver transplantation.  相似文献   
994.
Cholangiocarcinoma (CCA) is a severe malignancy usually producing a poor prognosis and high mortality rate. MicroRNAs (miRNAs) have been reported in association with CCA; however, the role miR-329 plays in the CCA condition still remains unclear. Therefore, this study was conducted to explore the underlying mechanism of which miR-329 is influencing the progression of CCA. This work studied the differential analysis of the expression chips of CCA obtained from the Gene Expression Omnibus database. Next, to determine both the expression and role of pituitary tumor transforming gene-1 (PTTG1) in CCA, the miRNAs regulating PTTG1 were predicted. In the CCA cells that had been intervened with miR-329 upregulation or inhibition, along with PTTG1 silencing, expression of miR-329, PTTG1, p-p38/p38, p-ERK5/ERK5, proliferating cell nuclear antigen (PCNA), Cyclin D1, Bcl-2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and caspase-3 were determined. The effects of both miR-329 and PTTG1 on cell proliferation, cell-cycle distribution, and apoptosis were also assayed. The miR-329 was likely to affect the CCA development through regulation of the PTTG1-mediated mitogen-activated protein kinase (MAPK) signaling pathway. The miR-329 targeted PTTG1, leading to inactivation of the MAPK signaling pathway. Upregulation of miR-329 and silencing of PTTG1 inhibited the CCA cell proliferation, induced cell-cycle arrest, and subsequently promoted apoptosis with elevations in Bax, cleaved caspase-3, and total caspase-3, but showed declines in PCNA, Cyclin D1, and Bcl-2. Moreover, miR-329 was also found to suppress the tumor growth by downregulation of PTTG1. To summarize, miR-329 inhibited the expression of PTTG1 to inactivate the MAPK signaling pathway, thus suppressing the CCA progression, thereby providing a therapeutic basis for the CCA treatment.  相似文献   
995.
996.
997.
Acute liver failure (ALF) is a disease resulted from diverse etiology, which generally leads to a rapid degenerated hepatic function. However, transplantation bone marrow–derived mesenchymal stem cells (BMSCs) transplantation has been suggested to relieve ALF. Interestingly, microRNA-214 (miR-214) could potentially regulate differentiation and migration of BMSCs. The present study aims to inquire whether miR-214 affects therapeutic potential of BMSCs transplantation by targeting PIM-1 in ALF. 120 male Wistar rats were induced as ALF model rats and transplanted with BMSCs post-alteration of miR-214 or PIM-1 expression. Further experiments were performed to detect biochemical index (alanine aminotransferase [ALT], aspartate transaminase [AST], total bilirubin [TBiL]), and expression of miR-214, PIM-1, hepatocyte growth factor (HGF), caspase 3, tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) in rat serum. Apart from the above detection, apoptosis of hepatocytes and Ki67 protein expression in hepatic tissues of rats were additionally assessed. After BMSCs transplantation with miR-214 inhibition, a decreased expression of ALT, AST, and TBiL yet an increased expression of HGF was shown, coupled with a decline in the expression of caspase 3, TNF-α, and IL-10. Meanwhile, alleviated hepatic injury and decreased apoptotic index of hepatic cells were observed and the positive rate of Ki67 protein expression was significantly increased. Moreover, miR-214 and caspase 3, TNF-α, and IL-10 decreased notably, while PIM-1 was upregulated in response to miR-214 inhibition. Strikingly, the inhibition of PIM-1 reversed effects triggered by miR-214 inhibition. These findings indicated that downregulation of miR-214 improves therapeutic potential of BMSCs transplantation by upregulating PIM-1 for ALF.  相似文献   
998.
999.
Wnt7a is a member of the Wnt family and has been reported to be involved in the carcinogenesis and progression of many types of human cancer. However, little is known about Wnt7a expression and function in gastric cancer (GC). In the present study, Wnt7a expression in GC tissues and cells was investigated, the correlation between Wnt7a expression and the prognosis was also examined. The effects of Wnt7a on proliferation, invasion, and metastasis were evaluated in vitro and in vivo. Furthermore, the expression of epithelial-mesenchymal transition (EMT) markers and hypermethylation of the Wnt7a promoter were both detected. Wnt7a was downregulated in GC and its expression was associated with poor prognosis of patients with GC. Moreover, upregulation of Wnt7a significantly suppressed the growth, invasion, and metastasis abilities of GC cells in vitro and in vivo. Mechanistically, Wnt7a was found to inhibit EMT process of GC cells. In addition, the reducing expression of Wnt7a was due to methylation of 5′-CpG island within the promoter. Furthermore, the tumor suppressor role of Wnt7a is independent of canonical Wnt/β-catenin signaling in GC cells. In conclusion, our findings demonstrated that Wnt7a could be used as a potential diagnostic marker and target for GC management.  相似文献   
1000.
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