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Several contributions of circulating microvesicles (MVs) to the endothelial dysfunction have been reported in the past; a head-to-head comparison of platelet- and monocyte–derived MVs has however never been performed. To this aim, we assessed the involvement of these MVs in vessel damage related processes, i.e., oxidative stress, inflammation, and leukocyte-endothelial adhesion. Platelets and monocytes isolated from healthy subjects (HS, n = 15) were stimulated with TRAP-6 and LPS to release MVs that were added to human vascular endothelial cell (hECV) culture to evaluate superoxide anion production, inflammatory markers (IL-6, TNFα, NF-κB mRNA expression), and hECV adhesiveness. The effects of the MVs-induced from HS were compared to those induced by MVs spontaneously released from cells of patients with ST-segment elevation myocardial infarction (STEMI, n = 7). MVs released by HS-activated cells triggered a threefold increase in oxidative burst in a concentration-dependent manner. Only MVs released from monocytes doubled IL-6, TNFα, and NF-κB mRNA expression and monocyte-endothelial adhesion. Interestingly, the effects of the MVs isolated from STEMI-monocytes were not superimposable to previous ones except for adhesion to hECV. Conversely, MVs released from STEMI-platelets sustained both redox state and inflammatory phenotype. These data provide evidence that MVs released from activated and/or pathologic platelets and monocytes differently affect endothelial behavior, highlighting platelet-MVs as causative factors of impaired endothelial function in the acute phase of STEMI.  相似文献   
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Chromatographic techniques were used to separate secondary products generated by thermal degradation of methyl linoleate hydroperoxides (MLHP). The MLHP were obtained by oxidation, selected, and concentrated by solid-phase extraction (SPE) and thin-layer chromatography (TLC). The purified MLHP were then thermo-degraded in the gas-chromatographic glass liner and analyzed on-line by gas chromatography-mass spectrometry (GC-MS). The MLHP were also thermodegraded and collected in a short silicic acid-packed column, eluted, separated by TLC, and then analyzed by GC. By considering the elution in TLC, the GC retention times and the GC-MS analyses, it was possible to characterize the mono- and the dioxygenated secondary products, particularly those having a boiling point higher than methyl linoleate. The peaks that corresponded to the mono-oxygenated products (epoxy, hydroxy, and keto) were identified, and, on the basis of their MS spectra, molecular structures were proposed. A specific elution order was suggested for keto derivatives: 9-keto,Δ10,12- and 13-keto,Δ9,11-octadecadienoate. The hydroxy derivatives, which show the typical fragmentations of 9-hydroxy,Δ10,12- and 13-hydroxy,Δ9,11-octadecadienoate, were also identified. On the other hand, identification of the di-oxygenated compounds was more difficult, and, therefore, it was not possible to indicate each positional isomer; however, their elution order could be epoxy-hydroxy and epoxy-keto derivatives.  相似文献   
24.
Lung cancer represents an extremely diffused neoplastic disorder with different histological/molecular features. Among the different lung tumors, non-small-cell lung cancer (NSCLC) is the most represented histotype, characterized by various molecular markers, including the expression/overexpression of the fibroblast growth factor receptor-1 (FGFR1). Thus, FGF/FGFR blockade by tyrosine kinase inhibitors (TKi) or FGF-ligand inhibitors may represent a promising therapeutic approach in lung cancers. In this study we demonstrate the potential therapeutic benefit of targeting the FGF/FGFR system in FGF-dependent lung tumor cells using FGF trapping (NSC12) or TKi (erdafitinib) approaches. The results show that inhibition of FGF/FGFR by NSC12 or erdafitinib induces apoptosis in FGF-dependent human squamous cell carcinoma NCI-H1581 and NCI-H520 cells. Induction of oxidative stress is the main mechanism responsible for the therapeutic/pro-apoptotic effect exerted by both NSC12 and erdafitinib, with apoptosis being abolished by antioxidant treatments. Finally, reduction of c-Myc protein levels appears to strictly determine the onset of oxidative stress and the therapeutic response to FGF/FGFR inhibition, indicating c-Myc as a key downstream effector of FGF/FGFR signaling in FGF-dependent lung cancers.  相似文献   
25.
Although human cytomegalovirus (HCMV) infection is mostly asymptomatic for immunocompetent individuals, it remains a serious threat for those who are immunocompromised, in whom it is associated with various clinical manifestations. The therapeutic utility of the few available anti‐HCMV drugs is limited by several drawbacks, including cross‐resistance due to their common mechanism of action, i.e., inhibition of viral DNA polymerase. Therefore, compounds that target other essential viral events could overcome this problem. One example of this is the 6‐aminoquinolone WC5 , which acts by directly blocking the transactivation of essential viral Early genes by the Immediate‐Early 2 (IE2) protein. In this study, the quinolone scaffold of the lead compound WC5 was investigated in depth, defining more suitable substituents for each of the scaffold positions explored and identifying novel, potent and nontoxic compounds. Some compounds showed potent anti‐HCMV activity by interfering with IE2‐dependent viral E gene expression. Among them, naphthyridone 1 was also endowed with potent anti‐HIV activity in latently infected cells. Their antiviral profile along with their innovative mechanism of action make these anti‐HCMV quinolones a very promising class of compounds to be exploited for more effective antiviral therapeutic treatment.  相似文献   
26.
The preparation of highly aromatic elastomers from a bisphenol A-based divinyl-terminated resin and polymerization with various aromatic silane containing compounds utilizing a room temperature hydrosilylation reaction is demonstrated. The polymers exhibit high thermal and oxidative stability with 5% weight losses around 430 and 350°C and char yields ranging from 35% to 40%. The thermosets maintained their elastomeric properties with good hardness and mechanical properties as measured by elongation measurements. The toughness of the thermosets was not improved with the inclusion of aromatic moieties but the hardness did appear to increase with the addition of more aromatic groups.  相似文献   
27.
Poly(ADP-ribose) polymerases (PARP) are proteins responsible for DNA damage detection and signal transduction. PARP inhibitors (PARPi) are able to interact with the binding site for PARP cofactor (NAD+) and trapping PARP on the DNA. In this way, they inhibit single-strand DNA damage repair. These drugs have been approved in recent years for the treatment of ovarian cancer. Although they share some similarities, from the point of view of the chemical structure and pharmacodynamic, pharmacokinetic properties, these drugs also have some substantial differences. These differences may underlie the different safety profiles and activity of PARPi.  相似文献   
28.
Resveratrol (RSV) is a natural compound that displays several pharmacological properties, including anti-cancer actions. However, its clinical application is limited because of its low solubility and bioavailability. Here, the antiproliferative and anti-inflammatory activity of a series of phenylacetamide RSV derivatives has been evaluated in several cancer cell lines. These derivatives contain a monosubstituted aromatic ring that could mimic the RSV phenolic nucleus and a longer flexible chain that could confer a better stability and bioavailability than RSV. Using MTT assay, we demonstrated that most derivatives exerted antiproliferative effects in almost all of the cancer cell lines tested. Among them, derivative 2, that showed greater bioavailability than RSV, was the most active, particularly against estrogen receptor positive (ER+) MCF7 and estrogen receptor negative (ER-) MDA-MB231 breast cancer cell lines. Moreover, we demonstrated that these derivatives, particularly derivative 2, were able to inhibit NO and ROS synthesis and PGE2 secretion in lipopolysaccharide (LPS)-activated U937 human monocytic cells (derived from a histiocytoma). In order to define the molecular mechanisms underlying the antiproliferative effects of derivative 2, we found that it determined cell cycle arrest at the G1 phase, modified the expression of cell cycle regulatory proteins, and ultimately triggered apoptotic cell death in both breast cancer cell lines. Taken together, these results highlight the studied RSV derivatives, particularly derivative 2, as promising tools for the development of new and more bioavailable derivatives useful in the treatment of breast cancer.  相似文献   
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Green Public Procurement (GPP) is a significant policy tool for reducing the environmental impacts of services and products throughout their whole life cycle. Scientific and easily verifiable environmental criteria, based on a life cycle approach, should be developed and used within procurement procedures. In this paper, Life Cycle Assessment (LCA) is applied to wood windows showing how it can support the criteria definition. After a foreword on GPP development in Italy, the evaluation features of the environmental performances of building materials and components are outlined. The LCA case study is then presented, describing the use of the analysis results to define the environmental criteria. LCA allowed to identify the main impacts and the critical processes of the window life cycle, giving a scientific framework to discuss GPP criteria with manufacturers associations and stakeholders. Nevertheless, it couldn’t help neither in identifying detailed criteria for GPP nor to define numerical thresholds to be used as reference in procurement procedures. The appropriate strategies should be selected taking into account the technical status of the market, the standard development and the voluntary industry commitments, involving manufacturers associations. Finally, some elements to develop a structured approach for GPP of construction materials are presented.  相似文献   
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