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21.
OBJECTIVES: To investigate the tracking of sugar-sweetened, carbonated soft drinks intake from age 15 to 33 years and the association between this intake and lifestyle factors and body weight. DESIGN: A longitudinal study with 18-20 years of follow-up. Data about diet, physical activity, smoking and dieting were collected in 1981/1979, 1991 and 1999. Body weight and height were measured in 1981/1979 and self-reported in 1999. SETTING: Oslo, Norway. SUBJECTS: Four hundred and twenty-two men and women. RESULTS: Tracking of soft drinks intake from adolescence into early adulthood (age 25 years) and from early adulthood into later adulthood (33 years) was moderate to high, while tracking from adolescence into later adulthood was low. Comparing those reporting a high intake of soft drinks in both 1991 and 1999 with those reporting a low intake at both times, male long-term high consumers were more likely to smoke (48 vs. 21%, P=0.002) and reported higher intakes of energy (12.2 vs. 10.2 MJ day(-1), P=0.005) and sugar (142 vs. 50 g day(-1), P<0.001) in 1999 than did long-term low consumers. Women high consumers were less likely to be physically active (14 vs. 42%, P=0.03) and had higher sugar intake (87 vs. 41 g day(-1), P<0.001) in 1999 than did women low consumers. There were no differences in body mass index, overweight or obesity in 1999 between long-term high and low consumers. CONCLUSION: In this study, stability of soft drinks intake from age 15 to 25 years and from age 25 to 33 years was moderate to high, while from age 15 to 33 years it was low. Soft drinks intake from age 25 to 33 years was associated with smoking and physical inactivity, but not with body weight.  相似文献   
22.
This paper reports a 3D-QSAR study using Catalyst software to explain the nature of interactions between flavor compounds and beta-lactoglobulin. A set of 35 compounds, for which dissociation constants were previously determined by affinity chromatography, was chosen. The set was divided into three subsets. An automated hypothesis generation, using HypoGen software, produced a model that made a valuable estimation of affinity and provided an explanation for the lack of correlation previously observed between the hydrophobicity of terpenes and the affinity for the protein. On the basis of these results, it appears that aroma binding to beta-lactoglobulin is caused by both hydrophobic interactions and hydrogen bonding, which plays a critical role. Catalyst appears to be a reliable tool for the application of 3D-QSAR study in aroma research.  相似文献   
23.
Conifers and other trees are constantly adapting to changes in light conditions, water/nutrient supply and temperatures by physiological and morphological modifications of their foliage. However, the relationship between physiological processes and anatomical characteristics of foliage has been little explored in trees. In this study we evaluated needle structure and function in Norway spruce families exposed to different light conditions and transpiration regimes. We compared needle characteristics of sun-exposed and shaded current-year needles in a control plot and a thinned plot with 50% reduction in stand density. Whole-tree transpiration rates remained similar across plots, but increased transpiration of lower branches after thinning implies that sun-exposed needles in the thinned plot were subjected to higher water stress than sun-exposed needles in the control plot. In general, morphological and anatomical needle parameters increased with increasing tree height and light intensity. Needle width, needle cross-section area, needle stele area and needle flatness (the ratio of needle thickness to needle width) differed most between the upper and lower canopy. The parameters that were most sensitive to the altered needle water status of the upper canopy after thinning were needle thickness, needle flatness and percentage of stele area in needle area. These results show that studies comparing needle structure or function between tree species should consider not only tree height and light gradients, but also needle water status. Unaccounted for differences in needle water status may have contributed to the variable relationship between needle structure and irradiance that has been observed among conifers.  相似文献   
24.
The stone-like otoliths from the ears of teleost fishes are involved in balance and hearing and consist of calcium carbonate crystallites embedded in a protein framework. We report that a previously unknown gene, starmaker, is required in zebrafish for otolith morphogenesis. Reduction of starmaker activity by injection of modified antisense oligonucleotides causes a change in the crystal lattice structure and thus a change in otolith morphology. The expression pattern of starmaker, along with the presence of the protein on the growing otolith, suggest that the expression levels of starmaker control the shape of the otoliths.  相似文献   
25.
Forde A  Pain E 《Science (New York, N.Y.)》2005,308(5720):428-430
Making the transition from postdoc to independent investigator is tough. Scientists who received prestigious fellowships or grants relate their experiences-and offer some advice.  相似文献   
26.
Previous exclosure studies measuring the top-down control of arthropod abundance and herbivory combined the effects of birds and bats. We experimentally partitioned bird predation from bat predation in a lowland tropical forest in Panama and measured the direct effects (arthropod abundance) and indirect effects (herbivory). The exclusion of birds and bats each directly increased arthropod abundance on plants: Bird-exclosed plants contained 65% more, and bat-exclosed plants 153% more, arthropods than controls. Birds and bats also indirectly increased herbivory: Bird-exclosed plants suffered 67% more, and bat-exclosed plants 209% more, herbivory than controls. We conclude that bats have dramatic ecological effects that were previously overlooked.  相似文献   
27.
28.
In the bacterium Escherichia coli, the Min proteins oscillate between the cell poles to select the cell center as division site. This dynamic pattern has been proposed to arise by self-organization of these proteins, and several models have suggested a reaction-diffusion type mechanism. Here, we found that the Min proteins spontaneously formed planar surface waves on a flat membrane in vitro. The formation and maintenance of these patterns, which extended for hundreds of micrometers, required adenosine 5'-triphosphate (ATP), and they persisted for hours. We present a reaction-diffusion model of the MinD and MinE dynamics that accounts for our experimental observations and also captures the in vivo oscillations.  相似文献   
29.
The spliceosome, a ribonucleoprotein complex that includes proteins and small nuclear RNAs (snRNAs), catalyzes RNA splicing through intron excision and exon ligation to produce mature messenger RNAs, which, in turn serve as templates for protein translation. We identified four point mutations in the U4atac snRNA component of the minor spliceosome in patients with brain and bone malformations and unexplained postnatal death [microcephalic osteodysplastic primordial dwarfism type 1 (MOPD 1) or Taybi-Linder syndrome (TALS); Mendelian Inheritance in Man ID no. 210710]. Expression of a subgroup of genes, possibly linked to the disease phenotype, and minor intron splicing were affected in cell lines derived from TALS patients. Our findings demonstrate a crucial role of the minor spliceosome component U4atac snRNA in early human development and postnatal survival.  相似文献   
30.
Recycling of greenhouse irrigation water in hydroponic tomato production requires a water remediation process to reduce the risk of pathogen proliferation and the accumulation of other chemical compounds. The dissolution of ozone into bulk irrigation solutions is an effective technology for reducing chemical contaminant and pathogen levels in greenhouse irrigation water. Greenhouse managers utilizing ozonation typically remove residual ozone prior to distribution to the crop. Removal of the active compound in this treatment process has been deemed a prudent measure intended to prevent ozone-based plant damage. This said, although atmospheric ozone has been extensively studied with respect to its phytotoxicity, there are very few studies available on ozone in the aqueous phase in which evidence to support the removal of ozone (on the basis of phytotoxicity) is provided. Furthermore, removal limits the overall efficacy of the treatment as the ozone is not available to treat distribution lines and emitters. The purpose of this study was to determine if aqueous ozone impacts tomato (Lycopersicon esculentum Mill. cv Matrix F1) productivity when applied directly to a mineral wool growth substrate via drip irrigation. At the highest aqueous ozone treatment level (3.0 mg L−1) significant increases in leaf area, shoot dry matter, and stem thickness were observed. There were no differences across all treatments in terms of net CO2 assimilation rate, stomatal conductance, internal leaf CO2 concentration, chlorophyll content index, and fruit production. A qualitative assessment of algae growth on the substrate surface was conducted. Both ozone treatments resulted in a visually discernible reduction in algae prevalence on the substrate surface. The results of this study do not support the removal of aqueous ozone (at the concentrations examined) prior to distribution when the solution is applied via drip irrigation in mineral wool hydroponic tomato production.  相似文献   
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