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381.
Alloreactive and autoreactive antibodies have been associated with the development of chronic lung allograft dysfunction (CLAD), but their pathogenic role is disputed. Orthotopic left lung transplantation was performed in the Fischer-344 to Lewis rat strain combination followed by the application of ciclosporine for 10 days. Four weeks after transplantation, lipopolysaccharide (LPS) was instilled into the trachea. Lungs were harvested before (postoperative day 28) and after LPS application (postoperative days 29, 33, 40, and 90) for histopathological, immunohistochemical, and Western blot analyses. Recipient serum was collected to investigate circulating antibodies. Lung allografts were more strongly infiltrated by B cells and deposits of immunoglobulin G and M were more prominent in allografts compared to right native lungs or isografts and increased in response to LPS instillation. LPS induced the secretion of autoreactive antibodies into the circulation of allograft and isograft recipients, while alloreactive antibodies were only rarely detected. Infiltration of B cells and accumulation of immunoglobulin, which is observed in allografts treated with LPS but not isografts or native lungs, might contribute to the pathogenesis of experimental CLAD. However, the LPS-induced appearance of circulating autoreactive antibodies does not seem to be related to CLAD, because it is observed in both, isograft and allograft recipients.  相似文献   
382.
Platelet concentrates and especially their further product platelet lysate, are widely used as a replacement for cell culturing. Platelets contain a broad spectrum of growth factors and bioactive molecules that affect cellular fate. However, the cellular response to individual components of the human platelet concentrate is still unclear. The aim of this study was to observe cellular behavior according to the individual components of platelet concentrates. The bioactive molecule content was determined. The cells were supplemented with a medium containing 8% (v/v) of platelet proteins in plasma, pure platelet proteins in deionized water, and pure plasma. The results showed a higher concentration of fibrinogen, albumin, insulin growth factor I (IGF-1), keratinocyte growth factor (KGF), and hepatocyte growth factor (HGF), in the groups containing plasma. On the other hand, chemokine RANTES and platelet-derived growth factor bb (PDGF-bb), were higher in the groups containing platelet proteins. The groups containing both plasma and plasma proteins showed the most pronounced proliferation and viability of mesenchymal stem cells and fibroblasts. The platelet proteins alone were not sufficient to provide optimal cell growth and viability. A synergic effect of platelet proteins and plasma was observed. The data indicated the importance of plasma in platelet lysate for cell growth.  相似文献   
383.
Potassium sodium niobate (KNN) thin films are potentially useful for energy harvesting devices and for lead-free piezoelectric microelectromechanical systems. This work reports the activation energies for nucleation, growth and perovskite phase transformation from a 0.5% manganese-doped KNN 2-methoxyethanol-based solution modified with acetylacetone and excess alkali precursors. The films were annealed in a rapid thermal processor (RTP) with a hold step at temperatures from 500 to 550°C. The activation energies for perovskite transformation and growth, determined by electron micrograph observation, were 687 ± 13 and 194 ± 10 kJ/mol. The activation energy for nucleation was 341 ± 20 kJ/mol. Based on these data, crystallization in KNN is found to be nucleation-limited; thus, it should be possible to reduce the crystallization temperature by utilizing a seed layer which provides nucleation sites, provided the organics are removed from the film.  相似文献   
384.
    
Zusammenfassung Die quantitative Bestimmung von Stärke mit Anthron eignet sich dazu, geringe Stärkereste auf maschinell gespültem Geschirr zu erfassen. Die Methode ist gleichermaßen anwendbar auf native Kartoffelstärke als auch auf deren Derivate in Form von kaltlöslicher Stärke, Distärkephosphat, kaltquellendem Stärkeacetat und oxidativ modifizierter Stärke. Die ermittelten Eichkurven sind bis 300 g/ml linear. Die untere Bestimmungsgrenze liegt bei 2,6 g/ml Stärke. Sowohl die alkalische Stärke- als auch die Anthronlösung bleibt bei Raumtemperatur bis zu 5 Tagen stabil.
A method for the determination of native and modified starches on dishes cleaned by dish-washers
Summary The quantitative determination of starch with anthrone has been used to determine minimal residues of starch on dishes cleaned by dishwashers. The method can also be applied to the determination of native starch in potatoes as well as in derivatives such as cold water soluble starch, with ionic phosphate groups cross-linked starch, starch acetates swelling in cold water and of oxidative modified starch. The standard curves are linear, up to 300 g/ml dissolved starch. The lowest concentration of starch that can be determined by the method is 2.6 g/ml. Both the alkaline starch solution and the anthrone reagent remain stable up to 5 days at ambient temperature.
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385.
Recently, the coffee constituents 5-O-caffeoylquinic acid (CGA) and N-methylpyridinium (NMP) were identified as inducers of the Nrf2/antioxidant-response element (ARE) detoxifying pathway under cell-culture condition. To study the impact of CGA and NMP on the Nrf2-activating properties of a complex coffee beverage, two different model coffees were generated by variation of the roasting conditions: a low-roast coffee rich in CGA and a heavy-roast low in CGA but containing high levels of NMP. Activation of the Nrf2/antioxidant-response element pathway was monitored in vitro and in vivo.  相似文献   
386.
Recent results from prospective cohort studies have shown that moderate coffee consumption is associated with a reduced risk for diabetes mellitus type II or Alzheimer's disease. Since reactive oxygen species (ROS) are believed to be involved in the pathogenesis of these diseases, antioxidants in coffee might contribute to this risk reduction. We aimed at elucidating whether a dark roast coffee beverage (CB) rich in N‐methylpyridinium ions (NMP: 785 μmol/L) and low in chlorogenic acids (CGA: 523 μmol/L) has stronger antioxidant effects on human erythrocytes than a CB prepared from a light roast with opposite proportions (CGA: 4538 μmol/L; NMP: 56 μmol/L). Following a 2‐wk wash out period, 500 mL of the respective CB was administered to 30 subjects daily for 4‐wk. Blood and spot urine samples were collected at the beginning and at the end of each intervention. Intake of the dark roast CB most effectively improved the antioxidant status of erythrocytes: superoxide dismutase and glutathione peroxidase activity decreased by 5.8 and 15%, respectively, whereas tocopherol and total glutathione concentrations increased by 41 and 14%, respectively. Furthermore, administration of the NMP‐rich CB led to a significant body weight reduction in pre‐obese subjects, whereas the CGA‐rich CB did not.  相似文献   
387.
The electrical conductance G of mechanical break-junctions fabricated from the rare-earth metal dysprosium has been investigated at 4.2 K where Dy is in the ferromagnetic state. In addition to the usual variation of the conductance while breaking the wire mechanically, the conductance can be changed reproducibly by variation of the magnetic field H, due to the large magnetostriction of Dy. For a number of contacts, we observe discrete changes in G(H) in the range of several G(0) = 2e(2)/h. The behavior of G(H) and its angular dependence can be quantitatively understood by taking into account the magnetostrictive properties of Dy. This realization of a magnetostrictive few-atom switch demonstrates the possibility of reproducibly tuning the conductance of magnetic nanocontacts by a magnetic field.  相似文献   
388.
Screening the volatiles isolated from a standard polypropylene material consisting of a polypropylene homopolymer, the filler talcum, and a mixture of antioxidants, for odor-active compounds by application of an aroma extract dilution analysis revealed 30 odorants with flavor dilution factors ranging from 1 to 64. Eighteen odor-active compounds were subsequently quantitated by gas chromatography-mass spectrometry using stable isotopically substituted odorants as internal standards, and their odor activity values (OAVs) were calculated as ratios of the concentrations to the odor threshold values. Five odorants showed OAVs ≥1, among which were hex-1-en-3-one (OAV 12), butanoic acid (OAV 3), as well as 4-methylphenol, butan-1-ol, and 2-tert-butylphenol (all OAV 1). A comparative analysis of polypropylene materials with different additives suggested plastic-like, pungent smelling hex-1-en-3-one as an ubiquitous key odorant. Odor-active amounts of alkylphenols, in particular plastic-like, phenolic smelling 2-tert-butylphenol, were additionally formed in the presence of talcum and phenolic antioxidants. Whereas the precursors of the phenols were thus obvious, the origin of hex-1-en-3-one was unknown. Injection molding showed only little influence on odorant concentrations.  相似文献   
389.
390.
Mass media campaigns, while often expensive, are proven, cost-effective interventions and should not be considered out-of-reach, especially where governments have some sway over media markets, where large media discounts are possible or where other novel strategies can be employed.  相似文献   
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