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981.
BackgroundThere is limited literature evaluating the impact of isolated cannabis use on outcomes for patients following spinal surgery. This study sought to compare 90-day complication, 90-day readmission, as well as 2-year revision rates between baseline cannabis users and non-users following thoracolumbar spinal fusion (TLF) for adult spinal deformity (ASD).MethodsThe New York Statewide Planning and Research Cooperative System (SPARCS) database was queried between January 2009 and September 2013 to identify all patients who underwent TLF for ASD. Inclusion criteria were age ≥18 years and either minimum 90-day (for complications and readmissions) or 2-year (for revisions) follow-up surveillance. Cohorts were created and propensity score-matched based on presence or absence of isolated baseline cannabis use. Baseline demographics, hospital-related parameters, 90-day complications and readmissions, and two-year revisions were retrieved. Multivariate binary stepwise logistic regression identified independent outcome predictors.Results704 patients were identified (n=352 each), with comparable age, sex, race, primary insurance, Charlson/Deyo scores, surgical approach, and levels fused between cohorts (all, p>0.05). Cannabis users (versus non-users) incurred lower 90-day overall and medical complication rates (2.4% vs. 4.8%, p=0.013; 2.0% vs. 4.1%, p=0.018). Cohorts had otherwise comparable complication, revision, and readmission rates (p>0.05). Baseline cannabis use was associated with a lower risk of 90-day medical complications (OR=0.47, p=0.005). Isolated baseline cannabis use was not associated with 90-day surgical complications and readmissions, or two-year revisions.ConclusionIsolated baseline cannabis use, in the absence of any other diagnosed substance abuse disorders, was not associated with increased odds of 90-day surgical complications or readmissions or two-year revisions, though its use was associated with reduced odds of 90-day medical complications when compared to non-users undergoing TLF for ASD. Further investigations are warranted to identify the physiologic mechanisms underlying these findings. Level of Evidence: III  相似文献   
982.
Microbial glycan degradation is essential to global carbon cycling. The marine bacterium Salegentibacter sp. Hel_I_6 (Bacteroidota) isolated from seawater off Helgoland island (North Sea) contains an α-mannan inducible gene cluster with a GH76 family endo-α-1,6-mannanase (ShGH76). This cluster is related to genetic loci employed by human gut bacteria to digest fungal α-mannan. Metagenomes from the Hel_I_6 isolation site revealed increasing GH76 gene frequencies in free-living bacteria during microalgae blooms, suggesting degradation of α-1,6-mannans from fungi. Recombinant ShGH76 protein activity assays with yeast α-mannan and synthetic oligomannans showed endo-α-1,6-mannanase activity. Resolved structures of apo-ShGH76 (2.0 Å) and of mutants co-crystalized with fungal mannan-mimicking α-1,6-mannotetrose (1.90 Å) and α-1,6-mannotriose (1.47 Å) retained the canonical (α/α)6 fold, despite low identities with sequences of known GH76 structures (GH76s from gut bacteria: <27%). The apo-form active site differed from those known from gut bacteria, and co-crystallizations revealed a kinked oligomannan conformation. Co-crystallizations also revealed precise molecular-scale interactions of ShGH76 with fungal mannan-mimicking oligomannans, indicating adaptation to this particular type of substrate. Our data hence suggest presence of yet unknown fungal α-1,6-mannans in marine ecosystems, in particular during microalgal blooms.Subject terms: Metagenomics, Microbial ecology, Structural biology, Fungal ecology, Molecular ecology  相似文献   
983.
984.
Osteopontin (OPN) is a secreted phosphoprotein which has been linked to tumor progression and metastasis in a variety of cancers including hepatocellular carcinoma (HCC). Previous studies have shown that OPN is upregulated during liver injury and inflammation. However, the role of OPN in hepatitis C virus (HCV)-induced liver disease pathogenesis is not known. In this study, we determined the induction of OPN, and then investigated the effect of secreted forms of OPN in epithelial to mesenchymal transition (EMT), migration and invasion of hepatocytes. We show the induction of OPN mRNA and protein expression by HCV-infection. Our results also demonstrate the processing of precursor OPN (75 kDa) into 55 kDa, 42 kDa and 36 kDa forms of OPN in HCV-infected cells. Furthermore, we show the binding of secreted OPN to integrin αVβ3 and CD44 at the cell surface, leading to the activation of downstream cellular kinases such as focal adhesion kinase (FAK), Src, and Akt. Importantly, our results show the reduced expression of epithelial marker (E-cadherin) and induction of mesenchymal marker (N-cadherin) in HCV-infected cells. We also show the migration and invasion of HCV-infected cells using wound healing assay and matrigel coated Boyden chamber. In addition, we demonstrate the activation of above EMT markers, and the critical players involved in OPN-mediated cell signaling cascade using primary human hepatocytes infected with Japanese fulminant hepatitis (JFH)-1 HCV. Taken together, these studies suggest a potential role of OPN in inducing chronic liver disease and HCC associated with chronic HCV infection.  相似文献   
985.
The adipokine tartrate resistant acid phosphatase (TRAP) 5a isoform exerts a growth factor-effect on pre-adipocytes. This study aimed to identify potential TRAP 5a interacting proteins in pre-adipocytes using pull down assays in combination with mass spectrometry. Nidogen-2, a protein shown to be expressed intracellularly and for secretion by pre-adipocytes, was shown to interact, through its globular G3 domain, with TRAP 5a in vitro. In vivo, TRAP 5a interacted with nidogen-2 in cultured 3T3-L1 mouse pre-adipocytes, as well as with transforming growth factor-β (TGF-β) interacting protein (TRIP-1), which is a protein that has previously been suggested to interact with TRAP in bone. In addition, TRAP 5a and nidogen-2 co-localized in adipose tissue cells in situ. These results indicate that TRAP 5a interacts with nidogen-2 and TRIP-1 in pre-adipocytic cells.  相似文献   
986.
A strategy of ex situ electrochemical method has been proposed for investigating the chloride effect on hemoglobin (Hb). Unlike the common electrochemical method that measures the chloride effect on Hb in bulk solution (in situ), the effects of chloride anion on Hb were investigated ex situ by adsorptive transfer voltammetry (AdTV) in this work. Gold electrode modified by self-assembled monolayer of 3-mercaptopropanoic acid (AuE/MPA) was prepared and then incubated in a series of Hb solutions containing different concentrations of chloride anion for adsorbing Hb-Cl (AuE/MPA/Hb-Cl). The resulting electrode was then measured in phosphate buffer solution by cyclic voltammetry. The corresponding voltammograms showed obvious promotion of the direct electron transfer of Hb with remarkable increase of peak currents, decrease of peak-to-peak separations, and negative shift of the formal potentials. As complementation, the adsorption behavior of Hb-Cl on AuE/MPA, the structural information of Hb-Cl, and the electrocatalytic ability of AuE/MPA/Hb-Cl toward hydrogen peroxide were investigated by surface plasmon resonance, circular dichroism spectrum, ultraviolet-visible spectrum and amperometry, respectively. The results indicate that the chloride effect resulted in more electroactive sites of Hb on the surface of electrode. Meanwhile, the specific and nonspecific interactions between Hb and chloride anion can be discriminated from the electrochemical parameters obtained by AdTV.  相似文献   
987.
ABSTRACT: BACKGROUND: The presence of diabetes mellitus poses a challenge in the treatment of patients with acute myocardial infarction (AMI). We aimed to evaluate the sex-specific outcomes of diabetic and non-diabetic patients with AMI who have undergone percutaneous coronary intervention (PCI). METHODS: Data of the Estonian Myocardial Infarction Registry for years 2006[EN DASH]2009 were linked with the Health Insurance Fund database and the Population Registry. Hazard ratios (HRs) with the 95 % confidence intervals (CIs) for the primary composite outcome (non-fatal AMI, revascularization, or death whichever occurred first) and for the secondary outcome (all cause mortality) were calculated comparing diabetic with non-diabetic patients by sex. RESULTS: In the final study population (n = 1652), 14.6 % of the men and 24.0 % of the women had diabetes. Overall, the diabetics had higher rates of cardiovascular risk factors, co-morbidities, and 3[EN DASH]4 vessel disease among both men and women (p < 0.01). Among women, the diabetic patients were younger, they presented later and less often with typical symptoms of chest pain than the non-diabetics (p < 0.01). Women with diabetes received aspirin and reperfusion for ST-segment elevation AMI less often than those without diabetes (p < 0.01). During a follow-up of over two years, in multivariate analysis, diabetes was associated with worse outcomes only in women: the adjusted HR for the primary outcome 1.44 (95 % CI 1.05 [MINUS SIGN] 1.96) and for the secondary outcome 1.83 (95 % CI 1.17 [MINUS SIGN] 2.89). These results were largely driven by a high (12.0 %) mortality during hospitalization of diabetic women. CONCLUSIONS: Diabetic women with AMI who have undergone PCI are a high-risk group warranting special attention in treatment strategies, especially during hospitalization. There is a need to improve the expertise to detect AMI earlier, decrease disparities in management, and find targeted PCI strategies with adjunctive antithrombotic regimes in women with diabetes.  相似文献   
988.
By the virtual screening method we have screened out Dihydrochalcone as a top-lead for the Alzheimer’s disease using the database of about 32364 natural compounds. The binding affinity of this ligand to amyloid beta (A) fibril has been thoroughly studied by computer simulation and experiment. Using the Thioflavin T (ThT) assay we have obtained the inhibition constant IC50 M. This result is in good agreement with the estimation of the binding free energy obtained by the molecular mechanic-Poisson Boltzmann surface area method and all-atom simulation with the force field CHARMM 27 and water model TIP3P. Cell viability assays indicated that Dihydrochalcone could effectively reduce the cytotoxicity induced by A. Thus, both in silico and in vitro studies show that Dihydrochalcone is a potential drug for the Alzheimers disease.  相似文献   
989.
990.
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