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991.
Kang SU  Shin YS  Hwang HS  Baek SJ  Lee SH  Kim CH 《PloS one》2012,7(4):e34988
Nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1) is induced by nonsteroidal anti-inflammatory drugs and possesses proapoptotic and antitumorigenic activities. Although tolfenamic acid (TA) induces apoptosis in head and neck cancer cells, the relationship between NAG-1 and TA has not been determined. This study investigated the induction of apoptosis in head and neck cancer cells treated by TA and the role of NAG-1 expression in this induction. TA reduced head and neck cancer cell viability in a dose-dependent manner and induced apoptosis. The induced apoptosis was coincident with the expression of NAG-1. Overexpression of NAG-1 enhanced the apoptotic effect of TA, whereas suppression of NAG-1 expression by small interfering RNA attenuated TA-induced apoptosis. TA significantly inhibited tumor formation as assessed by xenograft models, and this result accompanied the induction of apoptotic cells and NAG-1 expression in tumor tissue samples. Taken together, these results demonstrate that TA induces apoptosis via NAG-1 expression in head and neck squamous cell carcinoma, providing an additional mechanistic explanation for the apoptotic activity of TA.  相似文献   
992.
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value.  相似文献   
993.
994.
Obesity-related hepatic steatosis is commonly associated with central fat accumulation and alterations in adipocytokine secretion; however, the connection between nonobese hepatic steatosis and adipocytokines remains unclear. We aim to investigate this connection using an animal model of conditional hepatitis C virus (HCV) core-transgenic mice. Double transgenic mice (DTM) with doxycycline (dox)-regulated hepatic overexpression of the HCV core protein were fed standard rodent chow ad libitum following 1 month of a dox-rich diet. The mice exhibited nonobese hepatic steatosis at 2 months of age. The levels of leptin and adiponectin were assessed in 2-month-old DTM (i.e., HCV core-tetracycline transactivator (tTA)) and single transgenic mice (STM; i.e., tTA). The total fat mass and the body fat distribution of the mice were evaluated using dual-energy X-ray absorptiometry (DEXA) and magnetic resonance imaging (MRI). Microarray analyses and quantitative real-time PCR were conducted using RNA obtained from the visceral fat of paired DTM and STM. Adiponectin was administered intraperitoneally to the 2-month-old DTM. No significant differences of the various fat components were noted between the DTM and STM. Leptin mRNA was downregulated in the visceral fat of DTM (P = 0.011), and serum adiponectin protein levels were reduced in the DTM compared with those in the STM (P = 0.035). Adiponectin treatment also significantly ameliorated hepatic steatosis in the DTM compared to the controls (P = 0.024). In conclusion, HCV core-induced nonobese hepatic steatosis is associated with downregulation of the leptin gene in visceral fat and concurrent hypoadiponectinemia; however, these effects may be ameliorated by adiponectin treatment.  相似文献   
995.
Kim BM  Lee DH  Choi HJ  Lee KH  Kang SJ  Joe YA  Hong YK  Hong SH 《IUBMB life》2012,64(3):259-265
The recombinant kringle domain (UK1) of urokinase plasminogen activator was previously reported to exert antiangiogenic activity against Vascular Endothelial Growth Factor (VEGF)-induced angiogenesis in both in vitro and in vivo models. In this study, we explored the molecular signaling mechanisms involved in the antiangiogenic activity of UK1 by examining VEGF signaling proteins. VEGF165 stimulates the phosphorylation of VEGF signaling molecules, and pretreatment with UK1 blocked VEGF-induced signal transduction associated with proliferation, survival, and migration. UK1 also suppressed VEGF165-induced activation of MMP-2. Moreover, UK1 suppressed the phosphorylation and activation of VEGFR2 in VEGF-stimulated human umbilical cord vein endothelial cells (HUVECs) by blocking the dimerization of VEGFR2. Overall, our findings suggest that UK1 inhibits VEGF-induced proliferation, migration, and matrix metalloproteinase activity of HUVECs by suppressing VEGFR2 dimerization and subsequent angiogenic signals.  相似文献   
996.
Some of the most serious diseases involve altered size and structure of the arterial wall. Elucidating how arterial walls are built could aid understanding of these diseases, but little is known about how concentric layers of muscle cells and the outer adventitial layer are assembled and patterned around endothelial tubes. Using histochemical, clonal, and genetic analysis in mice, here we show that the pulmonary artery wall is constructed radially, from the inside out, by two separate but coordinated processes. One is sequential induction of successive cell layers from surrounding mesenchyme. The other is controlled invasion of outer layers by inner layer cells through developmentally regulated cell reorientation and radial migration. We propose that a radial signal gradient controls these processes and provide?evidence that PDGF-B and at least one other signal contribute. Modulation of such radial signaling pathways may underlie vessel-specific differences and pathological changes in arterial wall size and structure. VIDEO ABSTRACT:  相似文献   
997.
998.
Tubulin-α(1A/1B) C-terminal tail (CTT) has seven glutamic acid residues among the last 11 amino acids of its sequence that are potential sites for glutamylation. Cleavage of C-terminal tyrosine resulting in the detyrosinated form of tubulin-α(1A/1B) is another major modification. These modifications among others bring about highly heterogeneous tubulin samples in brain cells and microtubules, play a major role in directing intracellular trafficking, microtubule dynamics, and mitotic events, and can vary depending on the cell and disease state, such as cancer and neurodegenerative disorders. Identified previously using primary mass spectrometry (MS) ions and partial Edman sequencing, tubulin-α(1A/1B) glutamylation was found exclusively on the E(445) residue. We here describe the analysis of tubulin-α(1A/1B) glutamylation and detyrosination after 2-DE separation, trypsin and proteinase K in-gel digestion, and nanoUPLC-ESI-QqTOF-MS/MS of mouse brain and bovine microtubules. Tyrosinated, detyrosinated, and Δ2-tubulin-α(1A/1B) CTTs were identified on the basis of a comparison of fragmentation patterns and retention times between endogenous and synthetic peptides. Stringent acceptance criteria were adapted for the identification of novel glutamylation sites. In addition to the previously identified site at E(445), glutamylation on mouse and bovine tubulin-α(1A/1B) CTTs was identified on E(441) and E(443) with MASCOT Expect values below 0.01. O-Methylation of glutamates was also observed.  相似文献   
999.
The VAPB/ALS8 major sperm protein domain (vMSP) is implicated in amyotrophic lateral sclerosis and spinal muscular atrophy, yet its function in the nervous system is not well understood. In Caenorhabditis elegans and Drosophila, the vMSP is cleaved from its transmembrane anchor and secreted in a cell type-specific fashion. We show that vMSPs secreted by neurons act on Lar-like protein-tyrosine phosphatase and Roundabout growth cone guidance receptors expressed in striated muscle. This signaling pathway promotes Arp2/3-dependent actin remodeling and mitochondrial localization to actin-rich muscle I-bands. C. elegans VAPB mutants have mitochondrial localization, morphology, mobility, and fission/fusion defects that are suppressed by Lar-like receptor or Arp2/3 inactivation. Hence, growth cone guidance receptor pathways that remodel the actin cytoskeleton have unanticipated effects on mitochondrial dynamics. We propose that neurons secrete vMSPs to promote striated muscle energy production and metabolism, in part through the regulation of mitochondrial localization and function. VIDEO ABSTRACT:  相似文献   
1000.
Kim SJ  Moon GJ  Cho YH  Kang HY  Hyung NK  Kim D  Lee JH  Nam JY  Bang OY 《PloS one》2012,7(5):e37036
Preclinical and clinical studies have shown that the application of CD105(+) mesenchymal stem cells (MSCs) is feasible and may lead to recovery after stroke. In addition, circulating microparticles are reportedly functional in various disease conditions. We tested the levels of circulating CD105(+) microparticles in patients with acute ischemic stroke. The expression of CD105 (a surface marker of MSCs) and CXCR4 (a CXC chemokine receptor for MSC homing) on circulating microparticles was evaluated by flow cytometry of samples from 111 patients and 50 healthy subjects. The percentage of apoptotic CD105 microparticles was determined based on annexin V (AV) expression. The relationship between serum levels of CD105(+)/AV(-) microparticles, stromal cells derived factor-1α (SDF-1α), and the extensiveness of cerebral infarcts was also evaluated. CD105(+)/AV(-) microparticles were higher in stroke patients than control subjects. Correlation analysis showed that the levels of CD105(+)/AV(-) microparticles increased as the baseline stroke severity increased. Multivariate testing showed that the initial severity of stroke was independently associated with circulating CD105(+)/AV(-) microparticles (OR, 1.103 for 1 point increase in the NIHSS score on admission; 95% CI, 1.032-1.178) after adjusting for other variables. The levels of CD105(+)/CXCR4(+)/AV(-) microparticles were also increased in patients with severe disability (r = 0.192, p = 0.046 for NIHSS score on admission), but were decreased with time after stroke onset (r = -0.204, p = 0.036). Risk factor profiles were not associated with the levels of circulating microparticles or SDF-1α. In conclusion, our data showed that stroke triggers the mobilization of MSC-derived microparticles, especially in patients with extensive ischemic stroke.  相似文献   
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