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21.
Metachromatic leukodystrophy (MLD) is a lysosomal storage disease, caused by deficiency of arylsulfatase A (ASA), that manifests primarily in the white matter of the nervous system. Currently, no specific treatment exists that will reverse its fatal outcome. Replacement therapy has been hampered by the blood-brain barrier (BBB). To circumvent this problem we designed an ex vivo gene therapy strategy that includes the retrovirus-mediated ASA transduction of cells, such as activated lymphocytes, that are able to traverse the BBB or other membranes of the CNS. For this purpose, two recombinant retroviruses based on the pLXSN vector were produced, containing the wild-type ASA cDNA or a pseudodeficiency ASA cDNA, which encodes a smaller enzyme with normal activity. After transduction, ASA activity increased more than 100-fold in fibroblasts from an MLD patient. Furthermore, ASA-transduced MLD PBLs expressed 30 times higher ASA activity when compared with control PBLs. Moreover, cell culture experiments demonstrated that transduced fibroblasts could efficiently transfer ASA to deficient cells across a transwell barrier, whereas transduced MLD lymphocytes could transfer ASA to deficient fibroblasts only by direct cell-to-cell contact. Finally, ASA was taken up by normal oligodendrocytes and Schwann cells, the target myelinating glial cells for therapy in MLD. These data suggest possible short-term strategies for transfer of ASA into the CNS via transduced autologous cells while long-term strategies, related to autologous transduced bone marrow transplant, take effect in patients.  相似文献   
22.
This paper describes the outcome of discussions held during the Third International BCI Meeting at a workshop to review and evaluate the current state of BCI-related hardware and software. Technical requirements and current technologies, standardization procedures and future trends are covered. The main conclusion was recognition of the need to focus technical requirements on the users' needs and the need for consistent standards in BCI research.  相似文献   
23.
As is well known, pasteurization treatments are not sufficient for destroying heat resistance of spore forming microorganisms, which are prevented from germination and growing by pH reducing. So, the acidification process becomes one of the most important pre-treatments for the canning industry. It is commonly applied before pasteurization treatment with the purpose of inhibiting spore germination and for reducing heat resistance of the microorganism, thereby allowing to reduce the time or temperature values of the heat treatment. With the aim to reduce the pH of vegetables several techniques are available but their application is not easy to plan. Often, industries define operative conditions only on the basis of empirical experience, thus increasing the risk of microbial growth or imparting an unpleasant sour taste. With the aim of highlighting the correct plan and management of acidification treatments to reach safety without degrading quality of canned fruit and vegetables, the topics that are reviewed and discussed are the effects of low pH on heat resistance of the most important microorganisms, acidification techniques and significant process variables, the effect of low pH on sensorial properties, and future trends.  相似文献   
24.
The ongoing COVID-19 pandemic is having a tremendous effect on the current food system. The situation urges us to face many issues never experienced before, aimed at mitigating a multitude of sanitary and social risks. The current pandemic has affected the food system in many ways: significant changes in dietary habits and in the health status of people; the food chain is broken, which has an effect on food security (including making it difficult to find or to buy fresh food at affordable prices); unemployment or underemployment is rising due to the damages of the food sector; there is a lack of food-socialising events which has an effect on people’s mental status; and there are concerns about food safety. To mitigate all these issues, the implementation of innovative technologies urges. We have mapped the scientific studies and online information on 3D food printing (3DFP) about the effects of 3DFP on the food system and people’s health when adopted in food industry, restaurants, hospitals, schools, offices, homes, etc. Finally, this information has been examined in light to the future challenges of the food chain also considering the ongoing COVID-19 pandemic, demonstrating its potential benefits to mitigate this and future pandemics.  相似文献   
25.
The rate constants of the natural degradation processes of low density polyethylene and polypropylene films have been calculated on the basis of the molecular weights of weathered samples. Moreover, the optical densities, obtained by means of IR spectroscopy, indicate that the formations of carbonyl and vinyl groups are zero-order reactions.  相似文献   
26.
Polyurethanes (PUs) were synthesized from toluenediisocyanates (TDIs) and a polymeric diol having polydimethylsiloxane and polyoxyethylene blocks of the ABA type, ended with OH groups. Prepolymers, prepared in toluene solution using ratios [NCO]/[OH] ≥ 2, were crosslinked with triisopropanolamine (TIPA) (ratio [OH]/[NCO] = 1.1) (two-step process). PUs were also obtained with a one-step process using, contemporaneously, TDI, block copolymer, and, as crosslinking agent, TIPA or the glyceride of ε-hydroxyhexanoic acid. Polydimethylsiloxane (PDMSO) was prepared as a reference material. The course of the reaction between block copolymer and TDI was studied by differential scanning calorimetry in the absence and presence of benzoyl chloride (BzCl). Without BzCl, with ratios [NCO]/[OH] > 2, uncontrolled crosslinking side reactions occur. The properties of the PU films obtained with the two methods were studied both for the density of crosslinking and for gas transport properties. The two-step polymers are less crosslinked than the others and are characterized by higher diffusion coefficients and by higher permeability to gases. The permeability order is 10?9 (N cm3 cm?1 cm?1 cm Hg?1 s?1) for CH4, O2, CO, and N2 and is 10 times higher for CO2. The selectivity for the couple O2/N2 is higher than that obtained with PDMSO films. Considerable selectivities are shown for the couples CO2/N2 and CO2/CO. © 1995 John Wiley & Sons, Inc.  相似文献   
27.
Assistive technology is an emerging area, where robotic devices can help individuals with motor disabilities to achieve independence in daily activities. This paper deals with a system that provides remote control of Sony AIBO, a commercial mobile robot, within the assistive project ASPICE. The robot can be controlled by various input devices, including a Brain-Computer Interface. AIBO has been chosen for its friendly-looking aspect, in order to ease interaction with the patients. The development of the project is described by focusing on the design of the robot navigation system. Single step, semi-autonomous and autonomous navigation modes have been realized to provide different levels of control. Automatic collision avoidance is integrated in all cases. Other features of the system, such as the video feedback from the robotic platform to the user, and the use of AIBO as communication aid, are briefly described. The performance of the navigation system is shown by simulations as well as experiments. The system has been clinically validated, in order to obtain a definitive assessment through patient feedback.
Donatella MattiaEmail:
  相似文献   
28.
The aim of this work was to evaluate and compare the effects of conventional (hot air) and microwave drying on the lipid oxidation of stuffed pasta. Experiments were carried out on the pasta type ravioli dried by conventional and microwave treatments. Peroxide values and induction times were evaluated for the oil extracted from the stuffing. Peroxide values of the lipid extracts for the samples dried by conventional drying and microwave drying were similar (P-level = 0.51) and less than threshold acceptable value (25 mequiv O2/kg oil). The use of microwave processing could be a remarkable energy saving measure as well as a way of lowering production costs without compromising product quality.  相似文献   
29.
The formation of starch–lipid complexes plays an important role in extruded products. The effect of gluten proteins on thermal conditions at which the starch–lipid complexes formed during extrusion cooking of wheat flour with the addition of oleic acid was evaluated, considering wheat starch as a reference. The presence of gluten proteins in wheat flour extrudates brought about a reduction of the formation of starch–lipid complexes compared to blend of wheat starch and oleic acid extruded at the same operating conditions (melting enthalpy: 0.4 vs. 1.6 kJ kg?1). Moreover, the lubricant effect of oleic acid observed during extrusion of wheat starch (low values of specific mechanical energy and residence time) was not found during extrusion of wheat flour with addition of oleic acid because of the interaction between gluten proteins and oleic acid. This research points out the importance of proteins on biopolymer modifications and their effect on extrudate quality.  相似文献   
30.
The problem of the definition and evaluation of brain connectivity has become a central one in neuroscience during recent years as a way to understand the organization and interaction of cortical areas during the execution of cognitive or motor tasks. In this article, we propose the use of the directed transfer function (DTF) method on cortical signals estimated from high-resolution electroencephalography (EEG) recordings. An application of the proposed technique to the estimation of the cortical connectivity pattern in normal subjects and in one spinal-cord-injured patient is also provided.  相似文献   
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