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61.
We applied the scaffold-free culture method to chondrocytes and attempted to reconstitute articular cartilage grafts. Primary rat costal chondrocytes were immobilized into hollow fibers by centrifugation at a density of 3 x 10(8) cells/cm(3) to induce the formation of cylindrical-shaped multicellular aggregates (organoids) and cultured for one month. The organoids were evaluated by histological and gene expression analyses. Chondrocytes formed cylindrical organoids in hollow fibers (HFs). Histochemical analysis revealed the accumulation of a cartilage extracellular matrix (collagen and proteoglycan) around cells in the lumen of HFs with culture time, forming a low-cellular-density tissue similar to native cartilage by day 28. Furthermore, in contrast to that in traditional monolayer culture, the organoid maintained the gene expression of the cartilage extracellular matrix (type II collagen, aggrecan) for one month of culture. In conclusion, our organoid formation method was effective in producing a cartilage-like tissue. This result suggests that the technique may be applicable to the development of an articular cartilage graft.  相似文献   
62.
A commercial adzuki bean extract (AE) was evaluated for antioxidant effectiveness in cured and uncured cooked pork sausages. TBARS values, instrumental color evaluation and sensory panel scores were assessed. For uncured sausages, AE at 0.2% was equally effective as 0.1% butylated hydroxytoluene (BHT) in reducing TBARS values. Similarly, AE at 0.2% significantly (P<0.01) reduced the TBARS in cured sausages. Incorporation of 0.2% AE into sausages produced higher (P<0.05) CIE lab color a* value and lower (P<0.05) L* and b* values. Sensory panels did not detect any difference in color, odor, taste, flavor, and overall acceptance in uncured pork sausages with addition of 0.2% AE. However, there were adverse changes in the color and odor of cured sausages, even though the taste, flavor, and overall acceptance were similar. Therefore, the results suggest that AE is a potential antioxidant.  相似文献   
63.
Continuous cultures of Saccharomyces cerevisiae show a robust autonomous temperature compensated oscillation in many metabolic functions. Respiratory activity, a convenient output to measure, oscillates with a period of 40 min. Deletion of GTS1, whose protein product has homology to the circadian per protein, has been implicated in temporal events within yeast, causes a reduction in periodicity to 18 min (wild-type period 40-60 min). The dilution rate was steadily increased from 0.04/h to 0.085/h and the oscillation stabilized after four to six dilutions. However, Gts1p's involvement in the maintenance and generation of metabolic synchrony, and in the central oscillating loop, appear to be minimal, as the mutant oscillation was robust and autonomous. Deletion of GTS1 did cause decreased temperature compensation of the period of the oscillation from Q(10) = 1.07 for the wild-type to Q(10) = 1.6 for the mutant. Also the degree of nutrient compensation observed for the wild-type was not observed in the GTS1-null mutant strain. It is postulated that Gts1p is involved in the mechanism that communicates external conditions, such as temperature, to the central oscillating loop.  相似文献   
64.
Hard-to-degrade animal proteins are ubiquitously present throughout animal bodies. Enormous numbers of these proteins generated in the meat industry are converted to industrial wastes, the disposal of which is tremendously difficult. Most hard-to-degrade animal proteins are currently disposed of by incineration; however, this method has ecological disadvantages in terms of an apparent energy loss and the production of a large amount of carbon dioxide. As a result, an innovative solution to these problems has been sought. In this review, we focus on the degradation of three hard-to-degrade animal proteins (extracellular matrix proteins, collagen in particular, keratin, and prion proteins) and discuss the decomposing capability of thermophilic bacteria. These proteins are strongly resistant to proteinases because of their structural features; therefore, new approaches employing bacterial proteases with strong activity and broad specificity are required for practical application.  相似文献   
65.
ABSTRACT: We investigated the oxidative stability of soybean oil and fish oil fortified with iron solubilized by lactoferrin (FeLF). Oxidative stability was evaluated by measuring the induction period of the Rancimat test. The induction time of soybean oil added FeCl3 was decreased; however, that of added FeLF was not. This effect of lactoferrin was also observed in the iron-catalyzed oxidation offish oil at temperatures ranging from 50°C to 120°C, and at concentrations of iron ranging from 0 to 500 ppm. Thus, lactoferrin is considered useful as a natural iron stabilizer for food products containing polyunsaturated fatty acids.  相似文献   
66.
There has been much interest in the potential of using probiotic bacteria for treating allergic diseases. A double-blind, placebo-controlled study was conducted to examine the effectiveness of Lactobacillus GG (LGG) and L. gasseri TMC0356 (TMC0356) in alleviating Japanese cedar pollinosis (JCP), a seasonal allergic rhinitis caused by Japanese cedar pollen. Fermented milk prepared with the tested bacteria or placebo yoghurt was administered to 40 subjects with a clinical history of JCP for 10 weeks. Subjective symptoms, self-care measures and blood samples were compared between the two groups. Peripheral blood mononuclear cells (PBMCs) were collected from seven patients with JCP and in vitro cytokine production by the isolated PBMCs was analysed in the presence of heat-killed lactic acid bacteria. Consumption of the fermented milk significantly decreased the mean symptom score for nasal blockage after 9 weeks (P<0.05) and mean symptom-medication scores after 9 and 10 weeks when compared with the placebo group (P<0.01 and P<0.05 respectively). The tested strains of lactic acid bacteria affected cytokine production by isolated PBMCs in vitro in a strain-dependent manner. LGG significantly inhibited IL-4 and IL-5 production by PBMCs stimulated by both Cry j 1 and PHA. TMC0356 only suppressed IL-5 production stimulated by PHA. The fermented milk prepared with LGG and TMC0356 might be beneficial in JCP because of its effect on nasal blockage. The effects of LGG and TMC0356 might arise at least partly from their specific down-regulation of the human Th2 immune response.  相似文献   
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Bioaccumulation of synthetic musks in a marine food chain was investigated by analyzing marine organisms at various trophic levels, including lugworm, clam, crustacean, fish, marine mammal, and bird samples collected from tidal flat and shallow water areas of the Ariake Sea, Japan. Two of the polycyclic musks, HHCB and AHTN, were the dominant compounds found in most of the samples analyzed, whereas nitro musks were not detected in any of the organisms, suggesting greater usage of polycyclic musks relative to the nitro musks in Japan. The highest concentrations of HHCB were detected in clams (258-2730 ng/g lipid wt.), whereas HHCB concentrations in mallard and black-headed gull were low, and comparable with concentrations in fish and crab. These results are in contrast to the bioaccumulation pattern of polychlorinated biphenyls; for which a positive correlation between the concentration and the trophic status of organisms was found. Such a difference in the bioaccumulation is probably due to the metabolism and elimination of HHCB in higher trophic organisms. Temporal trends in concentrations of synthetic musks were examined by analyzing tissues of marine mammals from Japanese coastal waters collected during 1977-2005. HHCB concentrations in marine mammals have shown significant increase since the early 1990s, suggesting a continuous input of this compound into the marine environment. Comparison of the time trend for HHCB with those for PCBs and PBDEs suggested that the rates of increase in HHCB concentrations were higher than the other classes of pollutants. To examine the geographical distribution of HHCB, we have analyzed tissues of fish, marine mammals, and birds collected from several locations. Synthetic musks were not detected in a sperm whale (pelagic species) from Japanese coastal water and in eggs of south polar skua from Antarctica. While the number of samples analyzed is limited, these results imply a lack of long-range transportation potential of synthetic musks in the environment.  相似文献   
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