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961.
This study was designed to evaluate the effects of a single intramammary infusion of Panax ginseng extract on cell proliferation and death mechanism in bovine mammary gland during early involution. Eight mammary quarters from six non-pregnant cows in late lactation were infused with 10 ml of ginseng solution (3 mg/ml), six quarters were treated with 10 ml of placebo (vehicle alone) and six quarters were maintained as uninoculated controls. Milking was interrupted after infusion. Animals included in the three groups were slaughtered 7 d after inoculation and samples for histological analysis were taken. Morphometric analysis showed a significant increase in percentages of mammary tissue area occupied by stroma in ginseng-treated quarters compared with controls. A significant increase of immunostained area for bax protein and active caspase-3 was observed in ginseng-treated quarters compared with controls, whereas no differences were observed for bcl-2 immunostaining. Expression of bax mRNA was significantly higher in ginseng-treated quarters than in controls. The bax/bcl-2 ratio indicated a significant predominance of bax over bcl-2 mRNA expression in ginseng-treated quarters compared with controls. The rise of epithelial and stromal cell apoptosis in situ by TUNEL was more marked in quarters treated with ginseng than in controls. Ginseng inoculation had no effect on the number of epithelial and stromal proliferating cells labelled with Ki-67 antibody. Ratio of apoptotic to proliferating cells was higher in quarters treated with ginseng compared with controls, indicating a net loss of cells in parenchymal components. Also, the intramammary inoculation of ginseng extract at drying off increased the rate of mammary cell apoptosis without inhibiting cell proliferation. Taken together, these changes are indicative of mammary regression enhancement during early involution.  相似文献   
962.
The aim of this article is to observe differences between research areas when it comes to establish collaboration ties with local, national or international partners. It also intends to determine in what extent the collaboration can influence the patent transfer. A collaboration network between CSIC researchers and their external collaborators was built. Several statistical tests were used to find significant differences between research areas. A multiple regression model was also utilized in order to know what type of collaboration is more successful to transfer a patent. The results show that there are two well defined groups. A “Bio” group with a high international collaboration pattern but less national participation; and a “Physicist” group supported by a high proportion of national partners but with few international connections. The regression analysis found that the national collaboration is the variable that most increase the patent transfer.  相似文献   
963.
The Work Package 4 of the ORAMED project, a collaborative project (2008-11) supported by the European Commission within its seventh Framework Programme, is concerned with the optimisation of the extremity dosimetry of medical staff in nuclear medicine. To evaluate the extremity doses and dose distributions across the hands of medical staff working in nuclear medicine departments, an extensive measurement programme has been started in 32 nuclear medicine departments in Europe. This was done using a standard protocol recording all relevant information for radiation exposure, i.e. radiation protection devices and tools. This study shows the preliminary results obtained for this measurement campaign. For diagnostic purposes, the two most-used radionuclides were considered: (99m)Tc and (18)F. For therapeutic treatments, Zevalin(?) and DOTATOC (both labelled with (90)Y) were chosen. Large variations of doses were observed across the hands depending on different parameters. Furthermore, this study highlights the importance of the positioning of the extremity dosemeter for a correct estimate of the maximum skin doses.  相似文献   
964.
A mathematical programming model is presente for the optimal planning of the reuse of municipal solid waste (MSW) to maximize the economic benefit while simultaneously considering sustainability and safety criteria. The proposed methodology considers several phases of the supply chain including waste separation, distribution to processing facilities, processing to obtain useful products, and distribution of products to consumers. Additionally, the safety criteria are based on the potential fatalities associated with waste management. The proposed optimization model is formulated as a multiobjective optimization problem, which considers three different objectives including the maximization of the net annual profit, the maximization of the amount of reused MSW, and the minimization of the social risk associated with the supply chain. The proposed model is applied to a case study in the central‐west region of Mexico. The results show the tradeoff between the social risk and the economic and environmental criteria. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1881–1899, 2015  相似文献   
965.
Pickling is a preservation method of vegetables by brine immersion. Residual pickling solutions cannot be reused owing to high yeast content and the presence of polygalacturonase, which may produce vegetable softening. It has been reported that high‐pressure homogenization can reduce enzyme activity and microbial population in liquid foods. An investigation was aimed at studying the effect of high‐pressure homogenization cycles on polygalacturonase activity and yeast survival of residual pickling solutions, from processing of six vegetables. Each pickling solution was pumped through a homogenizing valve at 69 MPa pressure and was recirculated up to 15 times. Yeast counts and polygalacturonase activity were determined in treated solutions after being subjected to 1, 2, 5, 10, and 15 pressure cycles. Untreated and thermally treated solutions were used for comparison. Up to 4 log reductions in yeast inactivation was observed after five high‐pressure cycles treatments, contrasted with only 2 log reductions in thermal treatment. No clear relationship between enzyme inactivation and the number of high pressure cycles, or a thermal parallel effect, were observed. Copyright © 2007 Society of Chemical Industry  相似文献   
966.
967.
Increasingly high hopes are being placed on organic semiconductors for a variety of applications. Progress along these lines, however, requires the design and growth of increasingly complex systems with well‐defined structural and electronic properties. These issues have been studied and reviewed extensively in single‐component layers, but the focus is gradually shifting towards more complex and functional multi‐component assemblies such as donor–acceptor networks. These blends show different properties from those of the corresponding single‐component layers, and the understanding on how these properties depend on the different supramolecular environment of multi‐component assemblies is crucial for the advancement of organic devices. Here, our understanding of two‐dimensional multi‐component layers on solid substrates is reviewed. Regarding the structure, the driving forces behind the self‐assembly of these systems are described. Regarding the electronic properties, recent insights into how these are affected as the molecule's supramolecular environment changes are explained. Key information for the design and controlled growth of complex, functional multicomponent structures by self‐assembly is summarized.  相似文献   
968.
Orts  F.  Ortega  G.  Cucura  A. C.  Filatovas  E.  Garzón  E. M. 《The Journal of supercomputing》2021,77(8):8433-8444
The Journal of Supercomputing - Quantum image processing focuses on the use of quantum computing in the field of digital image processing. In the last few years, this technique has emerged since...  相似文献   
969.
Packed bed thermal energy storage (TES) systems have been identified in the last years as one of the most promising TES alternatives in terms of thermal efficiency and economic viability. The relative simplicity of this storage concept opens an important opportunity to its implementation in many environments, from the renewable solar‐thermal frame to the industrial waste heat recovery. In addition, its implicit flexibility allows the use of a wide variety of solid materials and heat transfer fluids, which leads to its deployment in very different applications. Its potential to overcome current heat storage system limitations regarding suitable temperature ranges or storage capacities has also been pointed out. However, the full implementation of the packed bed storage concept is still incomplete since no industrial scale units are under operation. The main underlying reasons are associated to the lack of a complete extraction of the full potential of this storage technology, derived from a successful system optimization in terms of material selection, design, and thermal management. These points have been evidenced as critical in order to attain high thermal efficiency values, comparable to the state‐of‐the‐art storage technologies, with improved technoeconomic performance. In order to bring this storage technology to a more mature status, closer to a successful industrial deployment, this paper proposes a double approach. First, a low‐cost by‐product material with high thermal performance is used as heat storage material in the packed bed. Second, a complete energetic and efficiency analysis of the storage system is introduced as a function of the thermal operation. Overall, the impact of both the selected storage material and the different thermal operation strategies is discussed by means of a thermal model which permits a careful discussion about the implications of each TES deployment strategy and the underlying governing mechanisms. The results show the paramount importance of the selected operation method, able to increase the resulting cycle and material usage efficiency up to values comparable to standard currently used TES solutions.  相似文献   
970.
Fluid thickening is the main compensatory strategy for patients with oropharyngeal dysphagia (OD) associated with aging or neurological diseases, and there is still no pharmacological treatment. We aimed to compare the effects of increasing bolus viscosity with that of acute stimulation with TRPV1, TRPA1 or TRPM8 agonists on the biomechanics and neurophysiology of swallow response in patients with OD. We retrospectively analyzed seven studies from our laboratory on 329 patients with OD. The effect of increasing shear viscosity up to 3682 mPa·s was compared by videofluoroscopy and pharyngeal sensory evoked potentials (pSEP) with that of adding to the bolus: capsaicin (TRPV1, 150 μM/10 μM), piperine (TRPA1/V1, 1 mM/150 μM), menthol (TRPM8, 1 mM/10 mM), cinnamaldehyde-zinc (TRPA1, 100 ppm–70 mM), citral (TRPA1, 250 ppm) or citral-isopulegol (TRPA1-TRPM8, 250 ppm–200 ppm). Fluid thickening improved the safety of swallow by 80% (p < 0.0001) by delaying bolus velocity by 20.7 ± 7.0% and time to laryngeal vestibule closure (LVC) by 23.1 ± 3.7%. Capsaicin 150μM or piperine 1 mM significantly improved safety of swallow by 50% (p < 0.01) and 57.1% (p < 0.01) by speeding time to LVC by 27.6% (p < 0.001) and 19.5% (p < 0.01) and bolus velocity by 24.8% (p < 0.01) and 16.9% (p < 0.05), respectively. Cinnamaldehyde-zinc shortened the P2 latency of pSEPs by 11.0% (p < 0.01) and reduced N2-P2 amplitude by 35% (p < 0.01). In conclusion, TRPV1 and TRPV1/A1 agonists are optimal candidates to develop new pharmacological strategies to promote the recovery of brain and swallow function in patients with chronic OD.  相似文献   
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