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51.
Atherosclerosis accounts for numerous cardiovascular diseases, and cytokines have a critical role in acceleration or suppression of disease. Salusin-α presents a new class of bioactive peptides that can have anti-atherogenic properties. Therefore, the effects of salusin-α on the expression of some pro- and anti-inflammatory cytokines and on TNF-α-induced inflammatory responses in human umbilical vein endothelial cells (HUVECs) were examined. The involvement of the NF-κB pathway in effects of salusin-α in HUVECs was checked using Bay 11-7082 as an NF-κB inhibitor. The mRNA expression of pro-inflammatory cytokines including IL-6, IL-8, and IL-18 and anti-inflammatory cytokine IL-1Ra was assessed by real-time PCR. The protein levels of cytokines were measured by the ELISA method. Salusin-α suppressed both mRNA and protein expression of pro-inflammatory cytokines and induced mRNA and protein expression of IL-1Ra in HUVECs. Salusin-α suppressed TNF-α-induced inflammatory responses in HUVECs. The down-regulatory or up-regulatory effects of salusin-α on expression of cytokines could not be influenced by Bay 11-7082 pretreatment. Our findings indicate anti-inflammatory effects of salusin-α and suggest a novel peptide-based therapeutic strategy for atherosclerosis.  相似文献   
52.
Many experimental and computational studies have identified key protein coding genes in initiation and progression of esophageal squamous cell carcinoma (ESCC). However, the number of researches that tried to reveal the role of long non-coding RNAs (lncRNAs) in ESCC has been limited. LncRNAs are one of the important regulators of cancers which are transcribed dominantly in the genome and in various conditions. The main goal of this study was to use a systems biology approach to predict novel lncRNAs as well as protein coding genes associated with ESCC and assess their prognostic values. By using microarray expression data for mRNAs and lncRNAs from a large number of ESCC patients, we utilized “Weighted Gene Co-expression Network Analysis” (WGCNA) method to make a big coding-non-coding gene co-expression network, and discovered important functional modules. Gene set enrichment and pathway analysis revealed major biological processes and pathways involved in these modules. After selecting some protein coding genes involved in biological processes and pathways related to cancer, we used “LncTar”, a computational tool to predict potential interactions between these genes and lncRNAs. By combining interaction results with Pearson correlations, we introduced some novel lncRNAs with putative key regulatory roles in the network. Survival analysis with Kaplan-Meier estimator and Log-rank test statistic confirmed that most of the introduced genes are associated with poor prognosis in ESCC. Overall, our study reveals novel protein coding genes and lncRNAs associated with ESCC, along with their predicted interactions. Based on the promising results of survival analysis, these genes can be used as good estimators of patients' survival, or even can be analyzed further as new potential signatures or targets for the therapy of ESCC disease.  相似文献   
53.
Intravascular optical coherence tomography (IV‐OCT) is a light‐based imaging modality with high resolution, which employs near‐infrared light to provide tomographic intracoronary images. Morbidity caused by coronary heart disease is a substantial cause of acute coronary syndrome and sudden cardiac death. The most common intracoronay complications caused by coronary artery disease are intimal hyperplasia, calcification, fibrosis, neovascularization and macrophage accumulation, which require efficient prevention strategies. OCT can provide discriminative information of the intracoronary tissues, which can be used to train a robust fully automatic tissue characterization model based on deep learning. In this study, we aimed to design a diagnostic model of coronary artery lesions. Particularly, we trained a random forest using convolutional neural network features to distinguish between normal and diseased arterial wall structure. Then, based on the arterial wall structure, fully convolutional network is designed to extract the tissue layers in normal cases, and pathological tissues regardless of lesion type in pathological cases. Then, the type of the lesions can be characterized with high precision using our previous model. The results demonstrate the robustness of the model with the approximate overall accuracy up to 90%.   相似文献   
54.
A novel series of tacrine based cyclopentapyranopyridine- and tetrahydropyranoquinoline-kojic acid derivatives were designed, synthesized, and evaluated as anti-cholinesterase agents. The chemical structures of all target compounds were characterized by 1H-NMR, 13C-NMR, and elemental analyses. The synthesized compounds mostly inhibited acetylcholinesterase enzyme (AChE) with IC50 values of 4.18–48.71 μM rather than butyrylcholinesterase enzyme (BChE) with IC50 values of >100 μM. Among them, cyclopentapyranopyridine-kojic acid derivatives showed slightly better AChE inhibitory activity compared to tetrahydropyranoquinoline-kojic acid. The compound 10-amino-2-(hydroxymethyl)-11-(4-isopropylphenyl)-7,8,9,11-tetrahydro-4H-cyclopenta[b]pyrano[2′,3′ : 5,6]pyrano[3,2-e]pyridin-4-one ( 6f ) bearing 4-isopropylphenyl moiety and cyclopentane ring exhibited the highest anti-AChE activity with IC50 value of 4.18 μM. The kinetic study indicated that the compound 6f acts as a mixed inhibitor and the molecular docking studies also illustrated that the compound 6f binds to both the catalytic site (CS) and peripheral anionic site (PAS) of AChE. The compound 6f showed moderate neuroprotective properties against H2O2-induced cytotoxicity in PC12 cells. The theoretical ADME study also predicted good drug-likeness for the compound 6f . Based on these results, the compound 6f seems to be a very promising AChE inhibitor for the treatment of Alzheimer's disease.  相似文献   
55.
2D transition metal‐dichalcogenides are emerging as efficient and cost‐effective electrocatalysts for the hydrogen evolution reaction (HER). However, only the edge sites of their trigonal prismatic phase show HER‐electrocatalytic properties, while the basal plane, which is absent of defective/unsaturated sites, is inactive. Herein, the authors tackle the key challenge of increasing the number of electrocatalytic sites by designing and engineering heterostructures composed of single‐/few‐layer MoSe2 flakes and carbon nanomaterials (graphene or single‐wall carbon nanotubes) produced by solution processing. The electrochemical coupling between the materials that comprise the heterostructure effectively enhances the HER‐electrocatalytic activity of the native MoSe2 flakes. The optimization of the mass loading of MoSe2 flakes and their electrode assembly via monolithic heterostructure stacking provides a cathodic current density of 10 mA cm?2 at overpotential of 100 mV, a Tafel slope of 63 mV dec?1, and an exchange current density (j0) of 0.203 µA cm?2. In addition, thermal and chemical treatments are exploited to texturize the basal planes of the MoSe2 flakes (through Se‐vacancies creation) and to achieve in situ semiconducting‐to‐metallic phase conversion, respectively, thus they activate new HER‐electrocatalytic sites. The as‐engineered electrodes show a 4.8‐fold enhancement of j0 and a decrease in the Tafel slope to 54 mV dec?1.  相似文献   
56.
Clean hydrogen production is highly promising to meet future global energy demands. The design of earth‐abundant materials with both high activity for hydrogen evolution reaction (HER) and electrochemical stability in both acidic and alkaline environments is needed, in order to enable practical applications. Here, the authors report a non‐noble 3d metal Cl‐chemical doping of liquid phase exfoliated single‐/few‐layer flakes of MoSe2 for creating MoSe2/3d metal oxide–hydr(oxy)oxide hybrid HER‐catalysts. It is proposed that the electron‐transfer from MoSe2 nanoflakes to metal cations and the chlorine complexation‐induced neutralization, as well as the in situ formation of metal oxide–hydr(oxy)oxides on the MoSe2 nanoflakes' surface, tailor the proton affinity of the catalysts, increasing the number and HER‐kinetics of their active sites in both acidic and alkaline electrolytes. The electrochemical coupling between doped‐MoSe2/metal oxide–hydr(oxy)oxide hybrids and single‐walled carbon nanotubes heterostructures further accelerates the HER process. Lastly, monolithic stacking of multiple heterostructures is reported as a facile electrode assembly strategy to achieve overpotential for a cathodic current density of 10 mA cm?2 of 0.081 and 0.064 V in 0.5 m H2SO4 and 1 m KOH, respectively. This opens up new opportunities to address the current density versus overpotential requirements targeted in pH‐universal hydrogen production.  相似文献   
57.

Background

Diabetes is an important risk factor for atherosclerosis. The diabetic foot is characterized by the presence of arteriopathy and neuropathy. When ischemia is diagnosed, restoration of pulsatile blood flow by revascularization may be considered for salvaging the limb. The treatment options are angioplasty with or without stenting and surgical bypass or hybrid procedures combining the two.

Aims

To evaluate the outcomes of severe ischemic diabetic foot ulcers for which percutaneous transluminal angioplasty (PTA) was considered as the first-line vascular procedure. Factors associated with successful PTA were also evaluated.

Methods

In 80 consecutive diabetic patients with foot ulcers and severe limb ischemia, PTAwas performed if feasible. All patients were followed until healing or for one year. Clinical and angiographic factors in fluencing outcomes after PTA were sought by univariate and multivariate analysis.

Results

PTAwas done in 73 of the 80 (91.2%) patients, and considered clinically succe ssful in 58(79.9%). Successful PTA was significantly higher in patients with Superficial femoral artery, posterior Tibialis and dorsalis pedis arteries involvement in the univariate analysis. Seven patients were expired during the study follow up due to MI, pulmonary thromboembolism and GI bleeding.

Conclusion

PTA in diabetic patients with severe ischemic foot ulcers provided favorable. Some parameters could be used for predicting PTA successfulness.
  相似文献   
58.
59.
There are large numbers of different intracellular signaling pathways regulated by Tyrosine kinases (Trk) receptors. Trk receptors, especially TrkB, are also frequently overexpressed in a variety of human malignant tumors. In this study, we have computationally designed small peptide-based inhibitors of TrkB and investigated their effects on the proliferation and apoptosis of two ovarian cancer cell lines. Molecular docking of TrkB with its ligand and antagonist, BDNF and Cyclotraxin B respectively, was carried out using HADDOCK program. A peptide library was constructed based on the critical residues involved in the TrkB binding site. After docking and optimization, two selected peptides were purchased and their effects on the viability and apoptosis of the cells were evaluated by performing MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) test and flow cytometry assay. Subsequently, the levels of expression and phosphorylation statues of TrkB and its two downstream genes including MAPK3 and eIF4E were assessed with western blot. We found that designed peptides effectively reduced TrkB, MAPK3 and eIF4E phosphorylation, reduced cell viability and induced apoptosis in the treated cells when compared to untreated cells. In conclusion, the BDNF/TrkB signaling is shown to be attenuated substantially in the presence of peptide inhibitors suggesting a strong inhibitory potential of the designed peptides for Trk family.  相似文献   
60.
Different glucokinase isoforms are produced by tissue-specific alternative RNA splicing in the liver and pancreatic islet, the only tissues in which glucokinase activity has been detected. To determine whether differences in protein structure brought about by alternative RNA splicing have an effect on glucose phosphorylating activity, we expressed cDNAs encoding four different hepatic and islet glucokinase isoforms and determined the Km and Vmax of each. When the glucokinase B1 and L1 isoforms were expressed in eukaryotic cells, both high Km glucose phosphorylating activity and immunoreactive protein were detected. However, when the glucokinase B2 and L2 isoforms were expressed, both of which differ by deletion of 17 amino acids in a region between the putative glucose and ATP-binding domains, no high Km glucose phosphorylating activity and much less immunoreactive protein were detected. When the glucokinase B1 and B2 isoforms were expressed in Escherichia coli as fusion proteins with glutathione S-transferase, affinity-purified B1 fusion protein was able to phosphorylate glucose whereas the B2 fusion protein was not, thus indicating that the lack of glucose phosphorylating activity from both the B2 and L2 isoforms is due to lack of intrinsic activity in addition to accumulation of less protein. The Km values of the B1 and L1 isoforms, which differ from each other by 15 amino acids at the NH2 terminus, were similar, but the Vmax of the B1 isoform was 2.8-fold higher than that of the L1 isoform. Mutagenesis of the first two potential initiation codons in the glucokinase B1 cDNA from ATG to GTC (methionine to valine) indicated that the first ATG was crucial for activity and is, therefore, the likely translation initiation codon. Messenger RNAs encoding both the B2 and L2 isoforms of glucokinase were detected in islet and liver by polymerase chain reaction amplification of total cDNA, indicating that mRNAs utilizing this weak alternate splice acceptor site in the fourth exon are normally present in both the liver and islet but as minor components. A regulatory role for weak alternate splice acceptor and donor sites in the glucokinase gene was suggested by examining the expression of the gene in the pituitary and in AtT-20 cells. Interestingly, although glucokinase mRNAs of appropriate sizes were detected in both the AtT-20 cells and rat pituitaries, neither exhibited any detectable high Km glucose phosphorylating activity.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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