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1.
Curvilinear reformatting of 3D magnetic resonance imaging data has been recognized by the medical community as a helpful noninvasive tool for displaying the cerebral anatomy. It consists of automatically creating, with respect to a reference surface, a series of equidistant curvilinear slices at progressively deeper cuts. In comparison with planar slices, it allows more precise localization of lesions and identification of subtle structural abnormalities. However, current curvilinear reformatting tools either rely on the time-consuming manual delineation of guiding curves on 2D slices, or require costly automatic brain segmentation procedures. In addition, they extract the skin and skull, impeding a precise topographic correlation between the location of the brain lesion and skin surface. This impairs planning of craniotomy for neurosurgery, and of the appropriate implantation of electrodes for intracranial electroencephalography in presurgical evaluation. In this work, we present a novel approach based on direct manipulation of the visualized volume data. By using a 3D painting metaphor, the reference surface can be defined incrementally, according to the principle that the user interacts with what she/he sees. As a response, an animation of the reformatting process is displayed. The focus of this paper is a new volume tagging algorithm behind user interactions. It works at an interactive frame rate on current graphics hardware.  相似文献   
2.
Immiscible blends of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and poly(styrene-co-acrylonitrile) (SAN) with a weight composition of 60/40 were compatibilised by polystyrene-block-polybutadiene-block-poly(methyl methacrylate) triblock terpolymers (SBM) using a two-stage melt-processing approach. In order to investigate the influence of the SBM composition on the compatibilisation efficiency, the block lengths of the triblock terpolymers were systematically varied. The resulting morphological features of the blend systems as function of SBM composition and processing parameters are correlated with the resulting thermal and thermo-mechanical properties. In the ideal case, SBM should be located at the interface as PS is miscible with PPE while PMMA is miscible with SAN. The elastomeric middle block as an immiscible component should remain at the interface. This particular morphological arrangement is known as the ‘raspberry morphology’. A detailed TEM analysis of the blend morphologies following initial extrusion-compounding revealed a high compatibilisation efficiency of the SBM types with equal lengths of the end blocks and, furthermore, the desired raspberry morphology was achieved. In contrast, high PS contents in comparison to the other blocks led to a pronounced micelle formation in the PPE phase. Further evaluation of the blend structures following injection-moulding indicated that the morphologies remain relatively stable during this second melt-processing step. A detailed thermal analysis of all blend systems supports the interpretation of the observed morphological features. The fundamental correlation between SBM composition and blend morphology established in this study opens the door for the controlled development of interfacial properties of such compatibilised PPE/SAN blends during melt-processing.  相似文献   
3.
Microsystem Technologies - We report the synergistic photoluminescent effect observed in heterogeneous colloidal solutions comprising different volumetric concentrations of Si and CdTe quantum dots...  相似文献   
4.
Glioblastoma multiforme is a lethal disease and represents the most common and severe type of glioma. Drug resistance and the evasion of cell death are the main characteristics of its malignancy, leading to a high percentage of disease recurrence and the patients’ low survival rate. Exploiting the modulation of cell death mechanisms could be an important strategy to prevent tumor development and reverse the high mortality and morbidity rates in glioblastoma patients. Ferroptosis is a recently described type of cell death, which is characterized by iron accumulation, high levels of polyunsaturated fatty acid (PUFA)-containing phospholipids, and deficiency in lipid peroxidation repair. Several studies have demonstrated that ferroptosis has a potential role in cancer treatment and could be a promising approach for glioblastoma patients. Thus, here, we present an overview of the mechanisms of the iron-dependent cell death and summarize the current findings of ferroptosis modulation on glioblastoma including its non-canonical pathway. Moreover, we focused on new ferroptosis-inducing compounds for glioma treatment, and we highlight the key ferroptosis-related genes to glioma prognosis, which could be further explored. Thereby, understanding how to trigger ferroptosis in glioblastoma may provide promising pharmacological targets and indicate new therapeutic approaches to increase the survival of glioblastoma patients.  相似文献   
5.
Sleeping Beauty (SB) is the first DNA transposon employed for efficient transposition in vertebrate cells, opening new applications for genetic engineering and gene therapies. A transposon-based gene delivery system holds the favourable features of non-viral vectors and an attractive safety profile. Here, we employed SB to engineer HEK293 cells for optimizing the production of a chimpanzee Adenovector (chAd) belonging to the Human Mastadenovirus C species. To date, chAd vectors are employed in several clinical settings for infectious diseases, last but not least COVID-19. A robust, efficient and quick viral vector production could advance the clinical application of chAd vectors. To this aim, we firstly swapped the hAd5 E1 with chAd-C E1 gene by using the CRISPR/Cas9 system. We demonstrated that in the absence of human Ad5 E1, chimp Ad-C E1 gene did not support HEK293 survival. To improve chAd-C vector production, we engineered HEK293 cells to stably express the chAd-C precursor terminal protein (ch.pTP), which plays a crucial role in chimpanzee Adenoviral DNA replication. The results indicate that exogenous ch.pTP expression significantly ameliorate the packaging and amplification of recombinant chAd-C vectors thus, the engineered HEK293ch.pTP cells could represent a superior packaging cell line for the production of these vectors.  相似文献   
6.
The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application.  相似文献   
7.
8.
Lipase from Aspergillus sp. obtained by solid‐state fermentation (SSF) on wheat bran (LWB), soybean bran (LSB) and soybean bran combined with sugarcane bagasse (LSBBC) were 67.5, 58 and 57.3 U of crude lipase per gram substrate, respectively. The optimum pH of activity and stability of the LWB was between 8 and 9, and the optimum temperature of activity and stability was 50 °C and up to 60 °C, respectively. The LSB and LSBBC showed two peaks of optimum pH (4 and 6) and optimal values of temperature and stability at 50 °C. The LSB was stable in the pH range of 6–7, while LSBBC in the range of pH 4–7. All the enzymes show activities on p‐nitrophenyl esters (butyrate, laurate and palmitate). LWB stood out either on the hydrolysis of sunflower oil, presenting 66.1% of the activity over commercial lipase and on the esterification of oleic acid and ethanol, surpassing the activities of the commercial lipases studied. The thin layer chromatography showed that LWB and LSB have produced ethyl esters from corn oil, while LWB produced it from sunflower oil.  相似文献   
9.
Fungal strains were screened for lipase producing activities and 10 strains were classified as good producers. Aspergillus sp., Fusarium sp., and Penicillium sp. exhibited the highest activities when fermented in wheat bran (WB) and soybean bran (SB). No fungal growth was observed using sugarcane bagasse (CB). An experimental design was applied to incorporate CB into the fermentation process for lipase production by Aspergillus sp. and Penicillium sp., and to evaluate the best moisture content for the substrate. Strains studied achieved maximum lipase activities with 25% CB combined with 75% WB or SB at 40% moisture content. The highest lipase activities were observed for WB and SB, and for SB combined with CB using Aspergillus sp. Fermentation of 96 h was the optimum period for enzyme production.  相似文献   
10.
Recent data have shown that parallel processing by the cerebral hemispheres can expand the capacity of visual working memory for spatial locations (J. F. Delvenne, 2005) and attentional tracking (G. A. Alvarez & P. Cavanagh, 2005). Evidence that parallel processing by the cerebral hemispheres can improve item identification has remained elusive. The authors used a novel variant of the attentional blink paradigm to show that the attentional blink is reduced if targets are divided between the hemispheres rather than directed to a single hemisphere. Parallel processing by the cerebral hemispheres can thus expand the capacity of processes involved in item identification. The authors also show that prior engagement of the attentional system may compromise the processing of items directed to the right visual field. This pseudoextinction may explain the failures of previous attempts to demonstrate that parallel processing can improve item identification (J. F. Delvenne, 2005; S. J. Luck, S. A. Hillyard, G. R. Mangun, & M. S. Gazzaniga, 1989). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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