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71.
In-situ hybridization provides a convenient and reliable method to detect human papillomavirus (HPV) infection in formalin-fixed paraffin-embedded tissue. Cases of conjunctival papillomas, conjunctival intraepithelial neoplasia (CIN), conjunctival carcinoma in situ (cCIS), and invasive squamous cell carcinoma (SCC), in which low-risk (LR) and/or high-risk (HR) HPV types were evaluated by RNA or DNA in-situ hybridization, were retrospectively identified. LR HPV types were frequently detected in conjunctival papillomas (25/30, 83%), including 17/18 (94%) with RNA probes, compared to 8/12 (75%) with DNA probes. None of the CIN/cCIS or SCC cases were positive for LR HPV by either method. HR HPV was detected by RNA in-situ hybridization in 1/16 (6%) of CIN/cCIS cases and 2/4 (50%) of SCC cases, while DNA in-situ hybridization failed to detect HPV infection in any of the CIN/cCIS lesions. Reactive atypia and dysplasia observed in papillomas was generally associated with the detection of LR HPV types. Collectively, our findings indicate RNA in-situ hybridization may provide a high-sensitivity approach for identifying HPV infection in squamous lesions of the conjunctiva and facilitate the distinction between reactive atypia and true dysplasia. There was no clear association between HPV infection and atopy in papillomas or dysplastic lesions.  相似文献   
72.
Precise prediction of protein secondary structures from the associated amino acids sequence is of great importance in bioinformatics and yet a challenging task for machine learning algorithms. As a major step toward predicting the ultimate three dimensional structures, the secondary structure assignment specifies the protein function. Considering a multilayer perceptron neural network, pruned for optimum size of hidden layers, as the reference network, advanced kinds of recurrent neural network (RNN) are devised in this article to enhance the secondary structure prediction. To better model the strong correlations between secondary structure elements, types of modular reciprocal recurrent neural networks (MRR-NN) are examined. Additionally, to take into account the long-range interactions between amino acids in formation of the secondary structure, bidirectional RNN are investigated. A multilayer bidirectional recurrent neural network (MBR-NN) is finally applied to capture the predominant long-term dependencies. Eventually, a modular prediction system based on the interactive combination of the MRR-NN and MBR-NN boosts the percentage accuracy (Q3) up to 76.91% and augments the segment overlap (SOV) up to 68.13% when tested on the PSIPRED dataset. The coupling effects of the secondary structure types as well as the sequential information of amino acids along the protein chain can be well cast by the integration of the MRR-NN and the MBR-NN.  相似文献   
73.
Mechanical stress following injury regulates the quality and speed of wound healing. Improper mechanotransduction can lead to impaired wound healing and scar formation. Vimentin intermediate filaments control fibroblasts’ response to mechanical stress and lack of vimentin makes cells significantly vulnerable to environmental stress. We previously reported the involvement of exosomal vimentin in mediating wound healing. Here we performed in vitro and in vivo experiments to explore the effect of wide-type and vimentin knockout exosomes in accelerating wound healing under osmotic stress condition. Our results showed that osmotic stress increases the size and enhances the release of exosomes. Furthermore, our findings revealed that exosomal vimentin enhances wound healing by protecting fibroblasts against osmotic stress and inhibiting stress-induced apoptosis. These data suggest that exosomes could be considered either as a stress modifier to restore the osmotic balance or as a conveyer of stress to induce osmotic stress-driven conditions.  相似文献   
74.
Around 77 new oncology drugs were approved by the FDA in the past five years; however, most cancers remain untreated. Small molecules and antibodies are dominant therapeutic modalities in oncology. Antibody-drug conjugates, bispecific antibodies, peptides, cell, and gene-therapies are emerging to address the unmet patient need. Advancement in the discovery and development platforms, identification of novel targets, and emergence of new technologies have greatly expanded the treatment options for patients. Here, we provide an overview of various therapeutic modalities and the current treatment options in oncology, and an in-depth discussion of the therapeutics in the preclinical stage for the treatment of breast cancer, lung cancer, and multiple myeloma.  相似文献   
75.
This work evaluates the use of a core–shell nozzle assembly in conjunction with gas jet spinning technique for production of bicomponent nanofibers from an immiscible polymer pair of polyvinylpyrrolidone (PVP) and poly(vinyl acetate) (PVAc) with three morphological forms—interpenetrating network (IPN), core–shell, and bilobal structurers—by varying the sets of miscible solvents offering different affinity for the polymers. Such fiber structures have strong potential in drug delivery and wound dressing applications. Solutions of PVP and PVAc in respective single solvents metered through a core–shell nozzle assembly meet at the exit of the nozzle and a liquid jet is initiated upon contact with a turbulent gas jet. The gas jet stretches the liquid jet into nanofibers. The results indicate that miscible solvent pairs with low affinity for one of the polymer component yield core–shell morphology with distinct polymer interfaces, while the miscible solvent pairs with high affinity for both polymers produce IPN morphology. Also, interchanging core and shell solutions does not alter the IPN morphology. Finally, bilobal nanofiber structures result from spinning of polymer solutions in miscible solvents with low affinity for the second polymer using a nonconcentric core–shell nozzle assembly. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48901.  相似文献   
76.
In this study, we aimed to produce a coloured polyester fabric through the in situ sonosynthesis of copper nanoparticles using copper sulphate, hydrazine, sodium hydroxide and polyvinylpyrrolidone. The treated fabrics were characterised by X‐ray diffraction, field emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and elemental mapping. Moreover, mechanical properties, wettability and antibacterial/antifungal activities of the treated fabrics were evaluated. Central composite design based on the response surface methodology was used to study the effect of copper sulphate, hydrazine hydrate and sodium hydroxide on the weight gain and colour of the treated fabrics. In addition to their roles as reducing agents, hydrazine and sodium hydroxide were responsible for the simultaneous aminolysis and hydrolysis of polyester, increasing the adsorption of nanoparticles on the surface. According to the results, the reddish brown samples treated with copper nanoparticles showed excellent antibacterial and antifungal efficiencies, improved tensile strength and decreased wettability.  相似文献   
77.
In this study, the effectiveness of ACP in inactivating Aspergillus flavus inoculated to military rations snack using response surface methodology (RSM) was investigated. Additionally, the effect of this treatment on the total count and yeast–mold count, as well as some quality properties of military rations snack, was examined. RSM was applied to study the voltage effects (5–15 kV), the distance between ACP emitter and sample (3–7 cm), and different treatment time (2–10 min) on the physicochemical properties of the military rations snack. Increasing voltage and time, together with reducing distance, caused a decrease in A. flavus, total count, yeast and mold count, total aflatoxin, as well as color difference. The peroxide value also increased with increasing voltage levels. The optimum conditions for treated military rations snack by ACP are as follows: a system voltage of 9 kV, a distance of 3 cm between the sample and the emitter, and a time of 6 min. Under these conditions, the responses, including the utmost reduction of 4.31 log CFU/g for the total count, 4.64 log CFU/g for yeast–mold count, and 2.98 log CFU/g for A. flavus were found from starting level of 5.2, 2, and 3.1 log CFU/g, respectively. It was found that snack samples had a 3.66% decrease in moisture content, 76.13% decrease in total aflatoxin, 3.01% increase in color difference, and 0.22 meq O2.kg/oil increase in peroxide value as a result of ACP application. ACP has the potential to increase microbiological safety by maintaining desirable quality properties in military rations snack.  相似文献   
78.
Drinking water quality is considered a continuing concern of human health. Herein, for the improvement of water quality, dual functioning core-shell (CS) nanofibers were developed by use of polysulfone (PSU)/graphene oxide (GO) as the adsorbent core layer for removing heavy metal ions and polyvinylpyrrolidone (PVP)/mint extract as the shell layer for inducing antioxidant activity to the water. Various analyses on the strip samples before and after the water treatment experiment were performed. ATR-FTIR by appearing or disappearing chemical bonds, TEM micrographs based on the formation of shell layer around the nanofibers, FESEM according to the uniformity and diameter of nanofibers, and EDX analysis based on the elemental and mapping results, verified the core-shell structure of nanofibers. The results of the antioxidant activity demonstrated that after the dissolution shell layer, radical scavenging capability of water was improved effectively. Thereafter, the remained core layer had a high capacity and efficiency for the adsorption of metal ions especially for CS3 with 70.9% and 58.7% efficiency for Fe(III) and Ni(II). By achieving 0.975 and 0.568 L/g partition coefficient (PC), the desired performance of CS3 (core layer: 15 wt% PSU, 0.5% GO and shell layer: 5 wt% PVP, and 2.5 wt% mint) was confirmed.  相似文献   
79.
80.
There are several techniques for preparing hydrogel biomaterials. Among these techniques, preparation of interpenetrating polymer networks hydrogel (IPNs) has been more interested during last years. IPNs are fabricated by the incorporation of monomers or polymeric chains in hydrogel network. Natural polymers such as hyaluronic acids have some advantages such as biocompatibility, biodegradability and non-toxicity. In this review, we would have a brief view to the interpenetrating polymer networks hydrogel based on hyaluronic acids and its applications as a drug delivery system and tissue engineering applications.  相似文献   
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