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431.
Globoid cell leukodystrophy or Krabbe disease is an inherited autosomal recessive disorder caused by mutations in the galactosylceramidase gene. The objective of the study was to present information about the fatty acid (FA) composition of the brain and serum of twitcher mice, a mouse model of Krabbe disease, compared to wild type, in order to identify biomarker of disease progression. We defined the FA profiles by identifying the main components present in serum and brain using GC‐EI‐MS analysis. The FA percentage composition was measured and data were analyzed considering the disease and the mouse age as experimental factors. Significant correlations were established, both in brain and in serum, in the fatty acid percentage composition of twitcher compared to wild type mice. The most abundant saturated fatty acid in brain was the palmitic acid (C16:0) with mean values significantly increased in twitcher mouse (p = 0.0142); moreover, three monounsaturated, three polyunsaturated (PUFA) and a plasmalogen were significantly correlated to disease. In the serum highly significant differences were observed between the two groups for three polyunsaturated fatty acids. In fact, the docosahexaenoic acid (C22:6n3c) content was significantly increased (p = 0.0116), while the C20 PUFA (C20:3n6c and C20:5n3c) were significantly decreased in twitcher serum samples. Our study shows a specific FA profile that may help to define a possible pattern that could distinguish between twitcher and wild type; these data are likely to provide insight in the identification of new biomarkers to monitor the disease progression and thereby permit the critical analysis of therapeutic approaches.  相似文献   
432.
ABSTRACT

Architecture and urban heritage have been decisive in the modernization of the historical centre of Santiago de Chile. As early as the first half of the nineteenth century they added value to this area of the capital. Public authorities, with the support of regulations, identified valuable urban heritage, incorporating it into urban transformations. For various practical or historical reasons, buildings and public spaces were preserved and eventually reused, giving birth to a renewed idea of planning, which took advantage of this existing heritage. The incorporation of new typologies into the colonial urban fabric, together with the conservation of traditional buildings and public spaces, produced memorable places, both in the republican and modern city. They enriched the urban practices and the city landscapes, offering a valuable continuity with the colonial and republican past. The integration of old and new stimulated the emergence of an urbanism of quality. This article focuses on three specific moments of that peculiar modernization process: the consolidation of the original colonial grid (1818–1846), Vicuña Mackenna’s Transformation Plan (1872–1875) and Santiago's first official Urbanization Plan (1939).  相似文献   
433.
Advances in the analysis of mycotoxins and its quality assurance   总被引:1,自引:0,他引:1  
This article covers the latest activities in mycotoxin analysis and the advances of its respective quality assurance. The majority of mycotoxin analyses carried out in the laboratories is still based on physicochemical methods, which are continually improved. For example, immunoaffinity columns and multifunctional clean-up columns have become of increasing importance and in some areas of mycotoxin analysis they have more or less displaced conventional liquid-liquid partitioning or column chromatography during clean-up. The need for rapid yes/no decisions on the other hand has led to a number of new screening methods. In particular, rapid and easy-to-use test kits based on immunoanalytical principles or the generation of artificial macromolecular receptors employed in molecularly imprinted polymers (MIPs) have made good progress. Further research in mycotoxin analysis is pursued in the field of biosensors and also the potential of infrared spectroscopic techniques as screening method has been demonstrated. In the area of multi mycotoxin analysis the most promising development was observed in mass spectrometry. At the same time, several interlaboratory studies in the field of mycotoxin analysis revealed problems proven by high between laboratory standard deviation and non-traceable results. This not only shows the necessity of reliable methods and well defined performance characteristics but also the need for appropriate calibrants of defined concentration and stated purity. A certified zearalenone (ZON) calibrant is already available and a certified calibrant containing various trichothecenes is currently under development. (Certified) reference materials are available for aflatoxins in a number of commodities, ochratoxin A (OTA) in wheat, deoxynivalenol (DON) in maize and wheat, and ZON in maize. With these measures important steps towards traceability of results in mycotoxin analysis have been achieved.  相似文献   
434.
According to the Italian laws, some categories of workers entrusted with duties possibly constituting a threat to security, physical safety, and health of third parties have to be screened to exclude the use/abuse of the following drugs of abuse: opiates, cocaine, cannabinoids, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, methadone, and buprenorphine. Toxicological tests can be performed with urinary on-site rapid screening devices, provided that sensitivities up to specified cutoffs are ensured. The present study reports performances, in terms of sensitivity, specificity, and accuracy, of an automatic on-site test and of an FPIA-based device, using gas chromatography/mass spectrometry (GC/MS) as a reference methodology. Three levels of concentration were tested, corresponding to the cutoff and to 2 and 3 times the limits, respectively. In terms of sensitivities, neither the on-site nor the benchtop instrumentations gave positive results, since values of zero percentage were obtained for concentrations up to 2-fold the limits. Even if good results were obtained in terms of specificity and accuracy by both devices, none of them seem to be adequate for the current application to the toxicological screening at workplaces. In fact, a rapid screening device can be used for drug tests provided that it ensures sensitivity at the prescribed cutoffs. Data showed that such is completely rejected and a more sensitive instrumentation should be preferred.  相似文献   
435.
Pulsed light (PL) was tested for its utility to improve the microbial quality and safety of ready-to-eat cooked meat products. Vacuum-packaged ham and bologna slices were superficially inoculated with Listeria monocytogenes and treated with 0.7, 2.1, 4.2 and 8.4 J/cm2. PL treatment at 8.4 J/cm2 reduced L. monocytogenes by 1.78 cfu/cm2 in cooked ham and by 1.11 cfu/cm2 in bologna. The effect of PL on lipid oxidation and sensory properties was also investigated. The 2-thiobarbituric acid values were very low and chromaticity parameters were within the normal values reported for cooked meat products. PL at 8.4 J/cm2 did not affect the sensory quality of cooked ham, while treatments above 2.1 J/cm2 negatively influenced the sensory properties of bologna. The combination of PL and vacuum packaging provided ham with an additional shelf-life extension of 30 days compared with only vacuum packaging. The shelf-life of bologna was not extended by PL.

Industrial relevance

The efficacy of pulsed light for the decontamination of surfaces offers excellent possibilities to ensure food safety and to extend shelf-life of ready-to-eat (RTE) products. The results of this study indicate that Listeria monocytogenes can be reduced by approximately 2 log cfu/cm2 in RTE cooked ham and 1 log cfu/cm2 in bologna using a fluence of 8.4 J/cm2. This dose does not affect the sensory properties of ham and triples its shelf-life when compared with conventional RTE products. On the contrary, fluences above 2.1 J/cm2 are not suitable for the treatment of bologna since sensory quality is modified.  相似文献   
436.
Profilins are pan-allergen proteins present in various plant foods and pollens. The objective was to develop a method for purification and characterisation of profilin from soy protein isolate. Furthermore, profilin was quantified in soy products and the effect of processing evaluated. Profilin was purified using poly-l-proline affinity chromatography, dialysis and ultrafiltration, and its quantification was implemented by indirect ELISA. Profilin in soymilks ranged from 4.37 ± 0.14 to 7.24 ± 0.30 mg/g protein, while in fermented products profilin ranged from 1.67 ± 0.02 to 5.47 ± 0.02 mg/g protein. Pasteurisation of soymilk was an ineffective method to completely eliminate profilin. Food matrix influenced thermal stability; at 100 °C, β-sheet and random coil structures were altered, while the α-helices remained intact. Induced fermentation of soybean meal by Bifidobacterium lactic, Lactobacillus plantarum and Saccharomyces cerevisiae resulted in 68.3% to 72.7% reduction of soy profilin. Heat treatment, fermentation and hydrolysis effectively reduced soy profilin.  相似文献   
437.
Soybean is a major source of protein and other nutrients and non-nutrient bioactives for human health. The objective was to compare the bioactive compounds of a low-protein (BRS 133) soybean in comparison to a high-protein (BRS 258) soybean cultivar. The high-protein soybean contained 17% lower carbohydrates and a lower chemical score (63) in relation to the low-protein soybean, which had a higher chemical score (76), associated with the higher methionine content (1.2%). Cultivar BRS 258 had more calcium (15.5%), phosphorus (30.1%), iron (18.7%), copper (9.0%) and zinc (11.5%), and a higher concentrations of lunasin, BBI and lectin (20.3%, 19.0% and 27.1%, respectively) than the low-protein cultivar. BRS 133 had 75.4% higher concentration of total isoflavones (5.1% of total aglycones) and 31.0% total saponins, as compared to BRS 258. It was concluded that the low-protein soybean cultivar contained higher isoflavones and saponins, but lower levels of minerals and bioactive peptides, such as lunasin.  相似文献   
438.
By following a rely-guarantee style of reasoning, we present novel termination and cost analyses for concurrent programs that, in order to prove termination or infer the cost of a considered loop: (1) infer the termination/cost of each loop as if it were a sequential one, imposing assertions on how shared-data is modified concurrently; and then (2) prove that these assertions cannot be violated infinitely many times and, for cost analysis, infer how many times they are violated. At the core of the analysis, we use a may-happen-in-parallel analysis to restrict the set of program points whose execution can interleave. Interestingly, the same kind of reasoning can be applied to prove termination and infer upper bounds on the number of iterations of loops with concurrent interleavings. To the best of our knowledge, this is the first method to automatically bound the cost of such kind of loops. We have implemented our analysis for an actor-based language, and showed its accuracy and efficiency by applying it on several typical applications for concurrent programs and on an industrial case study.  相似文献   
439.
Acute lymphoblastic leukemia type B (B-ALL) is the most common kind of pediatric leukemia, characterized by the clonal proliferation of type B lymphoid stem cells. Important progress in ALL treatments led to improvements in long-term survival; nevertheless, many adverse long-term consequences still concern the medical community. Molecular and cellular target therapies, together with immunotherapy, are promising strategies to overcome these concerns. Cannabinoids, enzymes involved in their metabolism, and cannabinoid receptors type 1 (CB1) and type 2 (CB2) constitute the endocannabinoid system, involved in inflammation, immune response, and cancer. CB2 receptor stimulation exerts anti-proliferative and anti-invasive effects in many tumors. In this study, we evaluated the effects of CB2 stimulation on B-ALL cell lines, SUP-B15, by RNA sequencing, Western blotting, and ELISA. We observe a lower expression of CB2 in SUP-B15 cells compared to lymphocytes from healthy subjects, hypothesizing its involvement in B-ALL pathogenesis. CB2 stimulation reduces the expression of CD9, SEC61G, TBX21, and TMSB4X genes involved in tumor growth and progression, and also negatively affects downstream intracellular pathways. Our findings suggest an antitumor role of CB2 stimulation in B-ALL, and highlight a functional correlation between CB2 receptors and specific anti-tumoral pathways, even though further investigations are needed.  相似文献   
440.
(1) Background: Bisphenol A (BPA) is an endocrine disruptor that is widely present in the environment and exerts adverse effects on various body tissues. The objective of this study was to determine its repercussions on bone tissue by examining its impact on selected functional parameters of human osteoblasts. (2) Methods: Three human osteoblast lines were treated with BPA at doses of 10−5, 10−6, or 10−7 M. At 24 h post-treatment, a dose-dependent inhibition of cell growth, alkaline phosphatase activity, and mineralization was observed. (4) Results: The expression of CD54 and CD80 antigens was increased at doses of 10−5 and 10−6 M, while the phagocytic capacity and the expression of osteogenic genes (ALP, COL-1, OSC, RUNX2, OSX, BMP-2, and BMP-7) were significantly and dose-dependently reduced in the presence of BPA. (5) Conclusions: According to these findings, BPA exerts adverse effects on osteoblasts by altering their differentiation/maturation and their proliferative and functional capacity, potentially affecting bone health. Given the widespread exposure to this contaminant, further human studies are warranted to determine the long-term risk to bone health posed by BPA.  相似文献   
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