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51.
The composition of fatty acids in abdominal subcutaneous adipose tissue and the correlation of fatty acid values of plasma and erythrocytes had not been reported in Japan. The aim of the present study was to investigate the fatty acid composition and correlation of plasma and erythrocyte phospholipids (PL) and adipose triacylglycerols (TG) in 75 adult patients admitted for non-malignant diseases. We also examined the relationship of n-3 and n-6 polyunsaturated fatty acid (PUFA) with patients’ characteristics. The total n-3 PUFA were 11.2, 11.8 and 1.9%, and the ratios of n-6/n-3 were 2.41, 1.87 and 8.20 in plasma and erythrocyte PL and adipose TG, respectively. There were the highest correlations for total n-3 PUFA and the n-6/n-3 ratio between plasma and erythrocyte PL and adipose TG. There was a positive correlation between n-3 PUFAs and age, but a negative correlation was found between n-6 PUFAs and age. There was no significant difference in the values of PUFAs in plasma and erythrocyte PL and adipose TG between men and women. The patients with cholesterol cholecystolithiasis showed a significantly lower proportion of eicosapentaenoic acid in plasma and erythrocyte PL than those of the other patients. Our findings suggest that PUFA in plasma and erythrocyte PL may be good biomarkers and more acceptable for studying participants than adipose TG.  相似文献   
52.
Miho Shibao 《Thin solid films》2008,516(9):2607-2610
The effects of light illumination on field effect transistors based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric methyl ester (PCBM) composite films have been studied. It is found that the light illumination on pure P3HT and PCBM generally resulted in decrease of the threshold voltages and increase of the mobilities by a little. In the composite film at the PCBM contents of x = [P3HT] / ([P3HT] + [PCBM]) = 0.67 ∼ 0.9, an ambipolar field transport appeared. The light illumination effect was observed remarkably in the shift of threshold voltage for the hole generation at x = 0.75. Variations of Hole and electron mobilities and threshold voltage of electron generation upon light illumination were basically similar to those of the pure materials. The results were discussed in terms of the light assisted carrier generation in field effects.  相似文献   
53.
The skin produces a plethora of antimicrobial peptides that not only show antimicrobial activities against pathogens but also exhibit various immunomodulatory functions. Human β-defensins (hBDs) are the most well-characterized skin-derived antimicrobial peptides and contribute to diverse biological processes, including cytokine production and the migration, proliferation, and differentiation of host cells. Additionally, hBD-3 was recently reported to promote wound healing and angiogenesis, by inducing the expression of various angiogenic factors and the migration and proliferation of fibroblasts. Angiogenin is one of the most potent angiogenic factors; however, the effects of hBDs on angiogenin production in fibroblasts remain unclear. Here, we investigated the effects of hBDs on the secretion of angiogenin by human dermal fibroblasts. Both in vitro and ex vivo studies demonstrated that hBD-1, hBD-2, hBD-3, and hBD-4 dose-dependently increased angiogenin production by fibroblasts. hBD-mediated angiogenin secretion involved the epidermal growth factor receptor (EGFR), Src family kinase, c-Jun N-terminal kinase (JNK), p38, and nuclear factor-kappa B (NF-κB) pathways, as evidenced by the inhibitory effects of specific inhibitors for these pathways. Indeed, we confirmed that hBDs induced the activation of the EGFR, Src, JNK, p38, and NF-κB pathways. This study identified a novel role of hBDs in angiogenesis, through the production of angiogenin, in addition to their antimicrobial activities and other immunomodulatory properties.  相似文献   
54.
Masubuchi S  Arai M  Machida T 《Nano letters》2011,11(11):4542-4546
We have fabricated graphene/graphene oxide/graphene (G/GO/G) junctions by local anodic oxidation lithography using atomic force microscopy (AFM). The conductance of the G/GO/G junction decreased with the bias voltage applied to the AFM cantilever V(tip). For G/GO/G junctions fabricated with large and small |V(tip)|. GO was semi-insulating and semiconducting, respectively. AFM-based LAO lithography can be used to locally oxidize graphene with various oxidation levels and achieve tunability from semiconducting to semi-insulating GO.  相似文献   
55.
A new method of supplying radical species to aqueous solutions using a hydrogen-oxygen flame is investigated. When a hydrogen-oxygen flame is directed on the surface of an aqueous solution, hydroxyl radicals (*OH) produced in the flame are extracted into the aqueous phase. The presence of *OH in the aqueous solution was confirmed by electron paramagnetic resonance with spin trapping using 5,5-dimethyl-1-pyrroline-N-oxide. The extraction of *OH into the aqueous solution was monitored using a quantitative analysis of hydrogen peroxide (H2O2). The effects of the hydrogen and oxygen gas flow rates, hydrogen/oxygen ratio, and atmosphere on H2O2 formation were studied. When the hydrogen-oxygen flame blew on a phosphate buffer solution (pH 6.7) under an Ar atmosphere, the concentration of H2O2 increased with the blowing time of the flame and the flow rate of hydrogen gas. Under air, nitrate and nitrite ions were formed in the aqueous phase in addition to H2O2, and the H2O2 concentration was lower than that under argon. The application of this new method to an aqueous solution of Cu(II)-ethylenediaminetetraacetic acid (EDTA) caused a remarkable decrease in the concentration of Cu(II)-EDTA and total organic carbon.  相似文献   
56.
57.
Immunostimulating effects of water extract from bulbus arteriosus in tuna were examined and found to enhance IgM production by human hybridoma HB4C5 cells. When tuna bulbus arteriosus extract was heated, the IgM production-stimulating activity was decreased or lost. To identify the active substance, the extract was partially purified by anion-exchange chromatography, and proteins contained in positive fractions were analyzed by LC-MS/MS. The positive fractions contained lactate dehydrogenase, triosephosphate isomerase, enolase, and haemoglobin. Each of these four proteins was verified to enhance IgM production by HB4C5 cells with the commercially available purified proteins, suggesting that all of these four proteins are active substances in the extract. The immunostimulatory effect of these proteins was also examined on mouse primary spleen lymphocytes in vitro. Lactate dehydrogenase enhanced IgA, IgG, and IgM production and triosephosphate isomerase enhanced IgA and IgG production. In particular, lactate dehydrogenase had the strongest Ig production-stimulating effect on HB4C5 cells and on mouse primary lymphocytes. Thus, fish viscera may serve as an important raw material for the enhancement of the acquired immune system, once processed.  相似文献   
58.
We examined effects of surface electric fields for the crystallization of calcite on polarized hydroxyapatite ceramics with and without polyacrylic acid (PAA) as soluble additive. Both on negatively and positively charged surfaces without PAA, the only precipitates were rhombohedra calcite crystals with the face of the {10.4} plane favorably oriented parallel to the surfaces. This oriented growth was explained by the nucleation theory in the presence of an external electric field. However, the addition of PAA drastically changed the situation of the calcite crystals, i.e., the crystallites were the hemispheric aggregates of calcite needles with a facetted rhombohedral {10.4} end face and flat island-shaped aggregates of ones with a rough (00.1) end face having a triangular shape. The calcite needles grew along the crystallographic [00.1] axis. This oriented growth was explained by epitaxy on the PAA–Ca2+ complexes adsorbing on the surfaces. The morphology of the PAA–Ca2+ complex assemblies adsorbing on the surfaces before the calcite nucleation was an important factor to control the structure of calcite aggregates formed following. This morphology was controlled by properties of the surface electric field and the spatial distribution of the negatively and positively charged sites in the PAA–Ca2+ complexes.  相似文献   
59.
Lactococcus lactis G50 is a candidate probiotic bacterium with immunomodulatory activity. We evaluated the suitability of strain G50 as orally administered probiotics on the basis of its resistance to simulated gastrointestinal (GI) stress, including the presence of lysozyme, low pH, and bile, carbohydrate preference, and bacterial cell surface composition in vitro. This strain survived GI stresses but its resistance to lysozyme was affected by the type of available carbohydrate in the growth medium; it was unaffected with lactose, xylose and galactose as the carbon source but was significantly lower for fructose, sucrose and glucose. The resistance of strain G50 to low pH was unaffected by carbon source. Resistance to bile was determined by two methods; growth and survival study and varied with carbon source. The growth of strain G50 with 0.3% bile was lowest in lactose-containing broth, higher in broth containing xylose or galactose, and highest in broth containing sucrose, glucose, or fructose. In contrast, the survival of cells after 3 h incubation with 0.3% bile was highest for lactose. The hydrophobicity of bacterial cells, which can be related to epithelial adhesion in certain cases, was also highest for lactose. The fatty acid composition of cells grown on lactose differed from that of cells grown on other carbon sources. These results suggest that survival of strain G50 in the GI tract depends on the kinds of carbohydrates available. Carbohydrate preferences were observed for other strains of lactic acid bacteria under conditions of GI stress, and this preference varied with the strain and the type of GI stress. Careful consideration should be given to the selection of carbohydrates for in vitro testing of the survival of lactic acid bacteria in the GI tract.  相似文献   
60.
In this study, a one-step method is discussed for producing uniform cell-sized microgels using glass capillaries filled with a binary polymer blend of polyethylene glycol (PEG) and gelatin. Upon decreasing temperature, phase separation of the PEG/gelatin blends and gelation of gelatin occur, and then the polymer blend forms linearly aligned, uniformly sized gelatin microgels in the glass capillary. When DNA is added to the polymer solution, gelatin microgels entrapping DNA are spontaneously formed, and the DNA prevents the coalescence of the microdroplets even at temperatures above the melting point. This novel method to form uniform cell-sized microgels may be applicable to other biopolymers. This method is expected to contribute to diverse materials science via biopolymer microgels and biophysics and synthetic biology through cellular models containing biopolymer gels.  相似文献   
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