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41.
Abstract: This study aimed to determine dietary vitamin D intake of U.S. Americans and Canadians and contributions of food sources to total vitamin D intake. Total of 7‐ or 14‐d food intake data were analyzed for vitamin D by a proprietary nutrient assessment methodology that utilized food intake data from the Natl. Eating Trends® service, portion size data from NHANES 1999–2004, and nutrient values using the Univ. of Minnesota's Nutrition Data System for Research software. Study participants were 7837 U.S. Americans and 4025 Canadians, ≥2‐y‐old males and females. The main outcome measures were total dietary vitamin D intake, percent contribution of foods to total vitamin D intake, and vitamin D intake by cereal and breakfast consumption habits. ANOVA was used to determine differences in means or proportions by age and gender and according to breakfast consumption habits. Mean vitamin D intake ranged from 152 to 220 IU/d. Less than 2% of participants in all age groups from the United States and Canada met the 2011 Recommended Daily Allowance (RDA) for vitamin D from foods. Milk, meat, and fish were the top food sources for vitamin D for both Americans and Canadians. Ready‐to‐eat (RTE) cereal was a top 10 source of vitamin D for Americans but not Canadians. Vitamin D intake was higher with more frequent RTE cereal and breakfast consumption in both countries, largely attributable to greater milk intake. Practical Application: Most U.S. Americans and Canadians do not meet the 2011 Inst. of Medicine recommended daily allowance (RDA) for vitamin D for their age groups from foods. Increasing breakfast and cereal consumption may be a useful strategy to increase dietary vitamin D intake to help individuals meet the RDA for vitamin D, particularly by increasing milk intake. However, it is likely that additional food fortification or vitamin D supplementation is required to achieve the RDA.  相似文献   
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The testosterone concentration in allantoic fluid between 90 and 150 days of gestation in cattle can be used to determine the fetal sex; values were 442 +/- 20-3 (S.E.M.) pg testosterone/ml for males fetuses and 215 +/- 8-2 pg/ml for female fetuses.  相似文献   
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Skin tumour development was studied in groups of mice painted once with 125 mug of 3-methylcholanthrene (MCA) either at 12:00 or at 24:00 MET. Eight animals were kept in each box. The animals were observed weekly for 20 months and all tumours were registered. There was no difference between the two groups of mice as regards tumour induction time or number of papilloma-bearing mice. In the groups of mice treated at 24:00 the number of skin tumours to develop was 9 per cent higher than in groups of mice treated at 12:00. This difference in papilloma yields is not statistically significant. Among female mice painted at 24:00 carcinoma-bearing animals were significantly more numerous (50 per cent) than among those painted at 12:00, whereas there was no difference between the groups of male mice. Considering the groups collectively (males + females), the intergroup difference (17 per cent) in advantage of painting at 24:00 was barely significant (0.5 less than p less than 0.10). There was no difference between the groups as regards the total number of carcinomas to occur. When the tumour yields in individual boxes were found to vary greatly. The slight increase in tumour yield after night painting correlates with the circadian variation in proliferative activity of the epidermidis. Previous reports in the literature have shown similar differences. Further investigations and better methods seem necessary before a definite conclusion can be drawn concerning a possible diurnal variation in the susceptibility of mouse skin to chemical carcinogenesis. It is also emphasized that it is necessary to exercise great caution when the results of classical epidermal chemical carcinogenesis experiments are to be interpreted. It seems necessary to observe animals for at least 15 months before any conclusion can be drawn.  相似文献   
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Environmental implications of municipal solid waste-derived ethanol   总被引:1,自引:0,他引:1  
We model a municipal solid waste (MSW)-to-ethanol facility that employs dilute acid hydrolysis and gravity pressure vessel technology and estimate life cycle energy use and air emissions. We compare our results, assuming the ethanol is utilized as E85 (blended with 15% gasoline) in a light-duty vehicle, with extant life cycle assessments of gasoline, corn-ethanol, and energy crop-cellulosic-ethanol fueled vehicles. We also compare MSW-ethanol production, as a waste management alternative, with landfilling with gas recovery options. We find that the life cycle total energy use per vehicle mile traveled for MSW-ethanol is less than that of corn-ethanol and cellulosic-ethanol; and energy use from petroleum sources for MSW-ethanol is lower than for the other fuels. MSW-ethanol use in vehicles reduces net greenhouse gas (GHG) emissions by 65% compared to gasoline, and by 58% when compared to corn-ethanol. Relative GHG performance with respect to cellulosic ethanol depends on whether MSW classification is included or not. Converting MSW to ethanol will result in net fossil energy savings of 397-1830 MJ/MT MSW compared to net fossil energy consumption of 177-577 MJ/MT MSW for landfilling. However, landfilling with LFG recovery either for flaring or for electricity production results in greater reductions in GHG emissions compared to MSW-to-ethanol conversion.  相似文献   
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A rat epididymal protein of 27 kDa was identified using neonatal tolerization. This study reports the production and characterization of a polyclonal antiserum to this protein. ELISA was used to demonstrate that this antiserum reacts strongly with epididymal sperm proteins, but has little or no reactivity with testicular proteins. Western blot analysis revealed that this polyclonal antiserum recognized a 27 kDa protein extracted from the corpus epididymidis as well as from spermatozoa from the corpus and cauda epididymides, and immunostaining revealed the presence of the protein in the corpus to cauda epididymides. Stronger reactivity was observed in the supranuclear region and stereocilla of principal cells of the corpus epididymidis and in the luminal content of the corpus and cauda epididymides. The testicular section showed no reactivity. Treatment with the antiserum resulted in time- and dose-dependent agglutination of rat spermatozoa. By indirect immunofluorescence, the antiserum localized proteins in the mid-piece region of rat spermatozoa. Studies were carried out to determine the age at which the protein first became apparent during postnatal development. The protein was expressed from day 40 onwards, as demonstrated by western blot analysis. The androgen regulation of this protein was ascertained by castration and supplementation studies. Expression of this protein showed a decline starting at day 14 after castration and by day 21 the protein was absent; however, androgen replacement resulted in the reappearance of the protein. The results of these studies indicate that the protein identified is specific to the epididymis, and is regulated by development and androgens. The importance of epididymis-specific proteins that are regulated by androgens in sperm maturation is discussed, and the need to ascertain the sequence of the protein and clone the cognate gene is indicated.  相似文献   
50.
HPLC-ABTS~+·在线法筛选细叶杜香叶部抗氧化活性成分   总被引:1,自引:0,他引:1  
利用HPLC-ABTS+.在线法对细叶杜香叶中的抗氧化活性成分进行筛选和分析鉴定,结果表明:在细叶杜香甲醇提取物的乙酸乙酯萃取组分中筛选到2种抗氧化活性成分,经质谱和核磁共振波谱分析鉴定为染料木苷和槲皮素。  相似文献   
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