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61.
The Nanoparticle (NP) and their oxides are being progressively used and expected to be more frequently used in textiles. Nanoparticle (NP) has higher toxicological risk than larger particles because of their physicochemical properties, chemical reactivity and biological activity. In fact, the stability of nano-oxide particles in the medium is always challenging as they lack functional groups to leverage upon textile materials directly. Thus, in many finishing processes, cross-linkers and/or adhesives are applied together with NP at the cost of inferior comfort, feel and fastness which tends to be toxic and prone to release NPs under common laundering, physical stress and sweat. This study shows that the diffusion of NPs into the fibre polymer matrix via dyeing technique could be much durable, safer in terms of cytotoxicity levels and easy to process for tailoring desired functional attributes. We studied the possibility of a simple application technique via dyeing of vinyl sulphone based reactive dye with four kinds of NPs followed by their cytotoxicity test using cell line A431.1% silica dyed sample have shown highest (198.5%) increase in tensile strength followed by 2% silica and 2% CNT whereas a decrease in elongation is highest in the case of CNT 2% (5.31%) and significantly enhancing the moisture management properties in case of CNT and silica. The study showed promising results in dyeing with TiO2, CNT (Carbon nanotubes), Silica and Alumina NPs in enhancing the mechanical, moisture management, and surface frictional properties to ensure comfortable and safe wear.  相似文献   
62.
Cell‐based biosensors treat living cells as sensing elements and are able to detect the functional information of biologically active analytes. Monitoring cytotoxicity with high sensitivity, rapidity and at low cost is of great interest in the fields of clinical diagnostics, environmental monitoring, food safety and security. This research investigates the behaviour of different cell types on nanostructured architectures. The development of cell‐based assays using bioimpedance devices has the potential of screening anti‐cancer drugs; these have a potential impact for developing new techniques and tools for the analysis of cells in the bio‐pharma industry. Gold impedance electrodes have been successfully fabricated for impedance measurement on cells cultured on the electrode surface which was modified with gold nanopillars with a height of 60 nm and 150 nm diameter in a highly ordered layout thanks to the e‐beam lithography technique. This article investigates the effects on the sensitivity achieved with the ECIS (Electric Cell‐substrate Impedance Spectroscopy) measurements while monitoring the cytotoxicity of two different drugs (Antrodia Camphorata extract and Nicotine) on different cell lines (HeLa, A549 and BALBc 3T3) cultured on the nanostructured devices. The change of morphology of cells growing on the nanostructured electrodes was also investigated through SEM imaging.  相似文献   
63.
This study aimed to assess the anti-aging potential of the ethanol extract of Passiflora edulis f. edulis Sims seeds, through in vitro determination of antioxidant activity and inhibition assays of some enzymes related to skin aging. Furthermore, using in silico methods (docking and molecular dynamics), were established the affinity of the majority compounds of the extract on the target enzymes, ending with the prediction of drug-likeness properties. The extract showed a high total phenolic content, represented mainly by flavonoids and phenolic acids, as well as a considerable antioxidant potential measured through the DPPH, FRAP and ORAC methods. In the inhibition assays of the enzymes collagenase, elastase and tyrosinase, IC50 values presented were optimal. Docking studies demonstrated marked binding ability of the extract constituients (specially, fisetin, galangin and S-eriodictyol) to the Collagenase and Tyrosinase. Molecular dynamics validated the stability and rationality of these molecular docking studies, MM/PBSA calculations provide strong evidence for both their specific heavy binding and how enzyme-ligand complex stabilized inside the catalytic domain, and drug-likeness studies showed suitable dermato-pharmacokinetics indices for most of components of extract. Findings from this study suggest that ethanol extract of P. edulis has a great potential as an anti-aging agent.  相似文献   
64.
One of the most severe environmental problems is heavy metal contamination, putting the world's sustainability at risk. Much effort has been put into developing sensors that can be taken anywhere to detect the environmental effects of heavy metals. Sensitivity, selectivity, multiplexed detection ability, and mobility enhance significantly when nanoparticles and nanostructures are incorporated into sensors. LDHs (layered double hydroxides) have gotten much attention in analytical chemistry in recent years because of their benefits, including their large specific surface area, ease of synthesis, low cost, and high catalytic efficiency and biocompatibility. LDHs are often manufactured as nanomaterial composites or created with specialized three-dimensional structures depending on the application. However, in these settings, LDHs (as color indicators, extracting sorbents, and electrochemical sensing) are usually restricted. Upcoming signs of progress and development possibilities of LDHs in analytical chemistry are reviewed in this paper to assist overcome these problems. Furthermore, the approaches used in the design of LDHs, including structural aspects, are defined and assessed in preparation for future analytical applications. The latest advances in optical and electrochemical sensors to detect heavy metals are described in this review. The sorts and characteristics of LDHs will be explored first. We will then go into microelectrode (or nanoelectrode) arrays, nanoparticle-modified electrodes, and microfluidic optical and electrochemical sensing assays in detail. This paper also discusses design strategies for LDH-based nanostructured sensors and the advantages of using nanomaterials and nanostructures.  相似文献   
65.
66.
Amyloid deposits are pathological hallmark of a large group of human degenerative disorders of unrelated etiologies. While accumulating evidence suggests that early oligomers may account for tissue degeneration, most detection tools do not allow the monitoring of early association events. Here we exploit bimolecular fluorescence complementation analysis to detect and quantify the dimerization of three major amyloidogenic polypeptides; islet amyloid polypeptide, β‐amyloid and α‐synuclein. The constructed systems provided direct visualization of protein‐protein interactions in which only assembled dimers display strong fluorescent signal. Potential inhibitors that interfere with the initial intermolecular interactions of islet amyloid polypeptide were further identified using this system. Moreover, the identified compounds were able to inhibit the aggregation and cytotoxicity of islet amyloid polypeptide, demonstrating the importance of targeting amyloid dimer formation for future drug development.  相似文献   
67.
Transfection of cells with a plasmid encoding for the first ten strands of the GFP protein (GFP1‐10) provides the means to detect cytosolic peptide import at low micromolar concentrations. Cytosolic import of the eleventh strand of the GFP protein either by electroporation or by cell‐penetrating peptide‐mediated import leads to formation of the full‐length GFP protein and fluorescence. An increase in sensitivity is achieved through structural modifications of the peptide and the expression of GFP1‐10 as a fusion protein with mCherry.  相似文献   
68.
We performed on‐plate enzyme and inhibition assays of glucose 6‐phosphate dehydrogenase using thin‐layer chromatography. The assays were accomplished based on different retardation factors of the substrates, enzyme, and products. All the necessary steps were integrated on‐plate in one developing process, including substrate/enzyme mixing, reaction starting, and quenching as well as product separation. In order to quantitatively measure the enzyme reaction, the developed plate was then densitometrically evaluated to determine the peak area of the product. Rapid and high‐throughput assays were achieved by loading different substrate spots and/or enzyme (and inhibition) spots in different tracks on the plate. The on‐plate enzyme assay could be finished in a developing time of only 4 min, with good track‐to‐track and plate‐to‐plate repeatability. Moreover, we determined the Km values of the enzyme reaction and Ki values of the inhibition (Pb2+ Cd2+ and Cu2+ as inhibitors), as well as the corresponding kinetics using the on‐plate assay. Taken together, our method expanded the application of thin‐layer chromatography in enzyme assays, and it could be potentially used in research fields for rapid and quantitative measurement of enzyme activity and inhibition.  相似文献   
69.
The homing properties of adipose tissue-derived mesenchymal stem cells (AdMSCs) have stimulated intravenous applications for their use in stem cell therapy. However, the soluble factors and corresponding cellular receptors responsible for inducing chemotaxis of AdMSCs have not yet been reported. In the present study, the migration capacity of human AdMSCs (hAdMSCs) toward various cytokines or growth factors (GFs) and the expression of their receptors were determined. In a conventional migration assay, PDGF-AB, TGF-β1, and TNF-α showed the most effective chemoattractant activity. When AdMSCs were preincubated with various chemokines or GF, and then allowed to migrate toward medium containing 10% FBS, those preincubated with TNF-α showed the highest migratory activity. Next, hAdMSCs were either preincubated or not with TNF-α, and allowed to migrate in response to various GFs or chemokines. Prestimulation with TNF-α increased the migration activity of hAdMSCs compared to unstimulated hAdMSCs. When analyzed by FACS and RT-PCR methods, hAdMSCs were found to express C-C chemokine receptor type 1 (CCR1), CCR7, C-X-C chemokine receptor type 4 (CXCR4), CXCR5, CXCR6, EGF receptor, fibroblast growth factor receptor 1, TGF-β receptor 2, TNF receptor superfamily member 1A, PDGF receptor A and PDGF receptor B at both the protein and the mRNA levels. These results indicate that the migration capacity of hAdMSCs is controlled by various GFs and chemokines. Prior in vitro modulation of the homing capacity of hAdMSCs could stimulate their movement into injured sites in vivo when administered intravenously, thereby improving their therapeutic potential.  相似文献   
70.
In the present study, the phytochemical study of the n-hexane extract from flowers of Nectandra leucantha (Lauraceae) afforded six known neolignans (1–6) as well as one new metabolite (7), which were characterized by analysis of NMR, IR, UV, and ESI-HRMS data. The new compound 7 exhibited potent activity against the clinically relevant intracellular forms of T. cruzi (amastigotes), with an IC50 value of 4.3 μM and no observed mammalian cytotoxicity in fibroblasts (CC50 > 200 μM). Based on the results obtained and our previous antitrypanosomal data of 50 natural and semi-synthetic related neolignans, 2D and 3D molecular modeling techniques were employed to help the design of new neolignan-based compounds with higher activity. The results obtained from the models were important to understand the main structural features related to the biological response of the neolignans and to aid in the design of new neolignan-based compounds with better biological activity. Therefore, the results acquired from phytochemical, biological, and in silico studies showed that the integration of experimental and computational techniques consists of a powerful tool for the discovery of new prototypes for development of new drugs to treat CD.  相似文献   
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