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The menisci exert a prominent role in joint stabilization and in the distribution of mechanical loading. Meniscal damage is associated with increased risk of knee OA. The aim of this study was to characterize the synovial membrane and meniscal tissues in patients undergoing arthroscopic partial meniscectomy for meniscal tear and to evaluate association with clinical outcomes. A total of 109 patients were recruited. Demographic and clinical data were collected. Visual Analogic Scale (VAS) measuring pain and Knee injury and Osteoarthritis Outcome Score (KOOS) were recorded at baseline and at 2-years follow-up. Histological and immunohistochemical characterizations were performed on synovial membranes and meniscal tissues. More than half of the patients demonstrated synovial mononuclear cell infiltration and hyperplasia. Synovial fibrosis was present in most of the patients; marked vascularity and CD68 positivity were observed. Inflammation had an impact on both pain and knee symptoms. Patients with synovial inflammation had higher values of pre-operative VAS and inflammation. Higher pre-operative pain was observed in patients with meniscal MMP-13 production. In conclusion, multivariate analysis showed that synovial inflammation was associated with pre-operative total KOOS scores, knee symptoms, and pain. Moreover, meniscal MMP-13 expression was found to be associated with pre-operative pain in multivariate analysis. Thus, targeting inflammation of the synovial membrane and meniscus might reduce clinical symptoms and dysfunction at the time of surgery.  相似文献   
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The goal of this study was the design and evaluation of a thiolated cyclodextrin providing high drug solubilizing and mucoadhesive properties for ocular drug delivery. Hydroxypropyl-β-cyclodextrin (HP-β-CD) was thiolated via a microwave-assisted method, resulting in a degree of thiolation of 33%. Mucoadhesive properties of thiolated HP-β-CD (HP-β-CD-SH) were determined via rheological measurements and ex vivo studies on isolated porcine cornea. Due to thiolation of HP-β-CD, a 2-fold increase of mucus viscosity and a 1.4-fold increase in residence time on isolated corneal tissue were achieved. After instillation, the mean precorneal residence time and AUC of dexamethasone (DMS) eye drops were 4-fold and 11.7-fold enhanced by HP-β-CD-SH, respectively. Furthermore, in the presence of HP-β-CD-SH, a constant high level of DMS in aqueous humour between 30 and 150 min after administration was observed. These results suggest that HP-β-CD-SH is an excellent excipient for ocular formulations of poorly soluble drugs in order to prolong their ocular residence time and bioavailability.  相似文献   
45.
The volume method is used to evaluate the productive potential of unexploited and minimally exploited geothermal fields. The distribution of PCO2 in shallow groundwaters delimits the geothermal fields. This approach is substantiated by the good correspondence between zones of high CO2 flux, and the areal extension of explored geothermal systems of high enthalpy (Monte Amiata and Latera), medium enthalpy (Torre Alfina) and low enthalpy (Viterbo). Based on the data available for geothermal fields either under exploitation or investigated by long-term production tests, a specific productivity of 40 t h−1 km−3 is assumed. The total potential productivity for the recent volcanic areas of Latium is about 28 × 103 t h−1, with 75% from low-enthalpy geothermal fields, 17% from medium-enthalpy systems, and 8% from high-enthalpy reservoirs. The total extractable thermal power is estimated to be 2220–2920 MW, 49–53% from low-enthalpy geothermal fields, 28–32% from medium-enthalpy systems, and 19–20% from high-enthalpy reservoirs.  相似文献   
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The main purpose of this article was to describe the morphology of mesenchymal stem cells (MSCs) differentiated in vitro towards osteogenic and chondrogenic lineages and to focus on the ultrastructural features associated with these processes. Human mononuclear cells (hMNC) were isolated, expanded, and analyzed for the expression of specific cell surface markers to demonstrate their stem cell characteristics. Human mononuclear cells were differentiated in vitro in an osteogenic and in a chondrogenic sense for 7, 14, 21, and 28 days. Subsequently, they were processed using electron microscopic analysis (FEISEM). Alizarin red and alcian blue staining were carried out to demonstrate the deposition of mineral salts and proteoglycans in the extracellular matrix. Undifferentiated MSCs showed a cell surface covered by filopodia and ondulopodia. During differentiation, the MSCs changed their shape from a round to a fibroblastic-like shape. At the end of the differentiation, several filaments with a parallel orientation in the osteogenic samples as well as a network organization in the chondrogenic samples were detected in the extracellular spaces. This study demonstrated that there are morphological features associated with the undifferentiated and differentiated states of the MSCs, which could be utilized as new parameters for identifying and classifying these cells.  相似文献   
47.
An analytical technique for correlating ground level return-stroke currents to the produced surface electromagnetic fields is discussed. The ground is realistically assumed to have finite conductivity. The lossless nonuniform transmission line model with cross section exponentially decreasing upward turns out to be a powerful, as well as plausible, discharge channel representation. By virtue of the analytical nature of this approach, a number of details typically ascribed to the electromagnetic performance of lightning appear on the whole suitably counted for. Therefore, the hypotheses employed and the results found for this investigation can be assumed to be useful for studying the discharge phenomenon  相似文献   
48.
Cerium(IV) oxide has been reported to catalyse the direct carboxylation of methanol to dimethylcarbonate, DMC. Nevertheless, the life of commercially available catalysts is quite short as after the first cycle the activity decreases and after a few cycles goes to zero. Noteworthy, no reports are in the literature about the stability of catalysts and their life. We have investigated the behaviour of catalysts and their de-activation using either surface techniques, such as XPS, or structural techniques, such as XRD. The reduction of Ce(IV) to Ce(III) and surface modification seem to be responsible for de-activation of the oxide. The results of a detailed study correlating the size and structure of particles to the activity of the catalysts are reported in this paper. In particular, pure commercial CeO2 is compared, using High Throughput Experiments (HTE), with CeO2 synthesised in our laboratory and with the latter loaded with Al or Fe at various concentrations. The hetero-metals have a different effect on the stabilization of the Ce-catalyst and on its activity. Al-loaded CeO2 affords the most interesting results in terms of lifetime and activity. Therefore, the correlation of the structural properties of CeO2 loaded with Al at a concentration variable between 3 and 40% to the activity in catalysis is discussed in detail. XPS and XRD data have been used for the characterization of the catalyst before and after a catalytic run. Pure synthesised CeO2 and CeO2 loaded with Al are able to maintain their activity for several cycles (apparent TON of several tens) or three days of operation without any treatment after recovery, with a much better performance than the commercial catalysts that, conversely, loose their activity after a few cycles. The size of the particles determines the activity of the catalyst and we show that particles having a size 15–60 nm are the most active, while particles sized micrometers are much less active.  相似文献   
49.
Many recently developed applications are related to the photocatalytic behavior of semiconductive oxides. Among the different oxides, titanium dioxide (TiO2) is one of the most interesting due to its high photocatalytic efficiency towards a great number of reactions and to its hydrophilic properties. Aim of this work is the evaluation and comparison of the photocatalytic properties of different crystalline titanium dioxide films, directly grown on titanium substrates by surface anodization (eventually followed by thermal annealing) and by Pulsed Laser Deposition (PLD) on titanium and silicon substrates, followed by thermal annealing. The structure and morphology of the layers were characterized by Scanning Electron Microscopy and X-Ray Diffraction and photocatalytic tests on stearic acid mineralization were performed. Results showed that the PLD layers possess a higher photocatalytic efficiency than anodized titanium. This can be attributed to the microstructured/microporous morphology of the related surfaces. Instead, PLD TiO2 layers with a relatively high content of the rutile phase have a reduced photocatalytic efficiency with respect to mainly anatase containing layers.  相似文献   
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