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71.
An inhibitor of the protein kinase CKII (CKII) was purified from leaves of Glycine max (L.) Merrill and was identified as coumestrol by structural analysis. Coumestrol inhibited the phosphotransferase activity of CKII toward β-casein, with an IC50 of about 5 μM. It acted as a competitive inhibitor with respect to ATP as a substrate, with an apparent Ki value of 7.67 μM. Coumestrol at 50 μM resulted in 50% and 30% growth inhibition of human breast cancer MCF-7 and colorectal cancer HCT116 cells, respectively. Coumestrol promoted senescence through the p53-p21Cip1/WAF1 pathway by inducing reactive oxygen species (ROS) production in MCF-7 and HCT116 cells. The ROS scavenger N-acetyl-l-cysteine (NAC), NADPH oxidase inhibitor apocynin and p22phox siRNA almost completely abolished this event. Overexpression of CKIIα antagonised cellular senescence mediated by coumestrol, indicating that this compound induced senescence via a CKII-dependent pathway. Since senescence is an important tumour suppression process in vivo, these results suggest that coumestrol can function by inhibiting oncogenic disease, at least in part, through CKII inhibition-mediated cellular senescence.  相似文献   
72.
73.
The antifungal effects of essential oils (EOs) on cultures of the known cheese fungal contaminants Penicillium spp. were evaluated. Cinnamon leaf and bark EOs were the most effective among 8 EOs tested. The main components of both cinnamon EOs were eugenol, cinnamaldehyde, and linalool. Both inhibited growth of Penicillium spp. at a concentration of 10% v/v (2,000 ppm/mm2) on a lawn cell plate. When tested using 3 commercially available cheese starters, cinnamon EOs showed no effect against the FD-DVS ABT-5 cheese starter. However, growth of lactobacilli was inhibited in the presence of ≥10% (v/v) of leaf and bark EOs for the KAZU 1 starter, and ≥5% (v/v) for the FD-DVS FLORA-DANICA starter. A concentration of 4,000 ppm/mm2 of cinnamon EOs completely inhibited growth of the Penicillium spp. that naturally contaminates the surface of Appenzeller cheese.  相似文献   
74.
This study investigated the anti-inflammatory effects of Pellinus linteus (PL) extract supplementation in healthy young men. The subjects were 18 healthy young males 20 years of age that were given 1.5 L of 0.12% PL extract orally (n=8) or a placebo (control group, n=10) daily for 4 weeks. The body composition, the white blood cell (WBC) count and differential as well as the serum cortisol, interleukin (IL)-1β, and IL-6 concentrations were measured before and after the supplementation. Serum concentrations of cortisol and IL-1β at rest after oral supplementation were significantly decreased compared to before treatment (p<0.01, p<0.05, respectively). However, there was no change in the IL-6. And also, these factors in PL extract supplement group were significantly reduced after performing the exercise compared to control group. These results suggest that oral PL extract supplements for 4 weeks had a significant effect on inhibition of inflammatory markers in healthy young men.  相似文献   
75.
This study was designed to evaluate the effect of the oral administration of fruit extracts (lemon and Japanese apricot) combined with red-ginseng on the endurance and availability of metabolic substrates in ICR mice. Administration of the fruit extracts and red-ginseng (RG) (1:1) significantly increased swimming capacity, by 40%, with increased expenditures of non-esterified fatty acids and triglycerides in the plasma of the mice after 1 week of feeding. There was no significant increase in swimming capacity with the fruit extract alone. These results suggest that the fruit extract could synergistically elevate the effects of red-ginseng on swimming capacity in the mice by increasing fat utilization and reducing the consumption of stored glucose.  相似文献   
76.
Saccharomyces cerevisiae sphinganine C4-hydroxylase encoded by the SUR2 gene catalyses the conversion of sphinganine to phytosphingosine. We isolated the SUR2 gene from Pichia ciferrii using nucleotide sequence homology to S. cerevisiae SUR2 to study hydroxylation of sphinganine in the sphingoid base overproducing yeast P. ciferrii. A positive clone was confirmed by nucleotide sequencing. A syringomycin-E resistance phenotype of a S. cerevisiae sur2-null mutant was complemented by expression of the cloned P. ciferrii SUR2 gene. Restoration of phytosphingosine production in the complemented strain was also confirmed, indicating that the cloned gene is a functional homologue of S. cerevisiae SUR2. .  相似文献   
77.
The effects of electron beam irradiation on microbial inactivation and quality of noninoculated and inoculated (Listeria monocytogenes) kimchi pastes were examined. Kimchi paste samples were irradiated at doses of 2, 4, 6, 8 and 10 kGy and stored for 21 days at 4 °C. Irradiation (10 kGy) reduced the populations of total aerobic bacteria, lactic acid bacteria, and yeast and moulds in the samples by 1.72, 2.24 and 0.86 log CFU g?1, respectively, compared to the control. In particular, coliforms were not detected at 8 and 10 kGy, and the population of Lmonocytogenes in inoculated samples was significantly decreased by 2.67 log CFU g?1. Electron beam irradiation delayed the changes in O2 and CO2 concentrations, pH, acidity and reducing sugar content observed in kimchi paste during storage. These results suggest that electron beam irradiation can be used to improve the microbiological safety and shelf life of kimchi paste.  相似文献   
78.
Changes in color, browning indices, enzyme activity, and physical and chemical quality during the storage period were investigated to assess the effectiveness of storage period extension along with the addition of ascorbic acid (AA) and citric acid (CA) to salted Chinese cabbage. After 16 days of storage, the change in chromaticity value showed treatment with 0.5% CA showed the lowest change in the brown index during the storage period. The control showed the highest residual activity of polyphenol oxidase among control, AA, and CA-treated salted cabbage. AA and CA treatment effectively inhibited the initial populations of microorganisms including total aerobic bacteria, lactic acid bacteria, and yeast and molds in salted Chinese cabbage during storage. Further, the texture, i.e., hardness, chewability, and elasticity, tended to decrease with increasing storage. These results suggest that treatment with AA could help maintain the quality of salted Chinese cabbage during the storage period.  相似文献   
79.
Food Science and Biotechnology - The objective of this study was to evaluate the functional properties of Weissella cibaria JW15 (JW15) by investigating its antagonistic and antioxidant activities....  相似文献   
80.
Oh  Seon-Min  Kim  Hui-yun  Bae  Ji-Eun  Ye  Sang-Jin  Kim  Byung-Yong  Choi  Hee Don  Choi  Hyun-Wook  Baik  Moo-Yeol 《Food science and biotechnology》2019,28(6):1723-1731
Food Science and Biotechnology - Physicochemical properties of acetylated (AC), cross-linked (CL), and hydroxypropylated (HP) chestnut starches were investigated. Modified chestnut starch showed...  相似文献   
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