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81.
Recently, bioactive benzoxazinoids were discovered in cereal grains and bakery products. In this study, we studied the uptake, distribution, and metabolism of these secondary metabolites using a pig model. Twelve benzoxazinoid compounds and their 4 transformation products were quantified in the pigs' diets and biofluids using high-performance liquid chromatography coupled to electrospray ionization triple quadrupole mass spectrometry. The 2-β-D-glucopyranosyloxy-4-hydroxy-1,4-benzoxazin-3-one (DIBOA-glc) was the most dominant benzoxazinoid (232 nmol/g DM) seconded by the double-hexose derivative of DIBOA (provisionally characterized here as DIBOA-glc-hex) in the rye-based diet. DIBOA-glc (derived from the diet and intestinal deglycosylation of DIBOA-glc-hex) was apparently reduced to 2-β-D-glucopyranosyloxy-1,4-benzoxazin-3-one (HBOA-glc), the most dominant benzoxazinoid in the blood (829 nmol/L). The benzoxazinoid compounds were excreted in the urine, with HBOA-glc (18 μmol/L) as a major metabolite. In this study, we determined for the first time the bioavailability of dietary benzoxazinoids that have high digestibility, distribution, and metabolism in mammals. These findings could be a milestone for the exploitation of healthful and pharmacological properties of benzoxazinoids.  相似文献   
82.
The application of hydrochars as soil amendments could be an option to ameliorate soil quality by enhancing nutrient and water‐holding capacity of sandy soils. But when hydrochar application is directly followed by sowing, it can decrease the soil mineral‐N concentration and the germination rate of crops. We currently lack evidence, whether these effects are persistent or transient and thus can be avoided by adjusting the application strategy, e.g., by prolonging the period between application and sowing. A set of pot trials with spring barley (Hordeum vulgare L.) was performed to study the initial and subsequent effects of different hydrochar amendments on germination, biomass production, and plant N availability. To this end, two subsequent cultivations of barley were grown on hydrochar‐amended soil–peat substrates. The first barley cultivation was sown directly after hydrochar application. After the harvest, the same substrates were cultivated with barley again. Germination, biomass production, and N concentration in the biomass were reduced when sowing directly followed the application of hydrochars. Differences in germination rate and biomass production between hydrochar treatments depended on the hydrochar feedstock. A recultivation of the hydrochar‐amended substrates 9 weeks after hydrochar application showed no significant effects on germination and biomass production. The N concentration in plants was still lower in the hydrochar treatments despite additional fertilization. The N immobilized during the first cultivation period was not released in the following weeks. We conclude that the germination‐inhibiting substances in hydrochars were removed in the weeks after soil incorporation. This is probably due to microbial degradation of hydrochar components and a consecutive immobilization of mineral N. Hydrochar amendment had only short‐term effects on germination and biomass production of barley that can be avoided by applying hydrochar at least 4 weeks prior to sowing. The N concentration in plants was persistently low even 4 months after hydrochar application which can only be redeemed by adjusting the fertilization strategy.  相似文献   
83.
OBJECTIVE: To report treatment and wound healing after radical surgical mass excision in the equine buccal region. STUDY DESIGN: Clinical case reports. ANIMALS: An 11-year-old Warmblood gelding and a 9-year-old Norwegian Trotter gelding. METHODS: Large tumoral masses were removed from the buccal region by radical electrosurgery, creating large defects into the oral cavity. Wound ultimately healed by second intention. RESULTS: Buccal defects in both horses healed well by second intention without tumor recurrence. CONCLUSIONS: Locally invasive tumors involving the cheek region of the horse can be successfully treated by radical electroexcision alone, creating transmural defects up to 14 cm length x 8 cm height. CLINICAL RELEVANCE: Large transmural defects in the cheek region of the horse, formed by radical surgery can heal satisfactorily by second intention healing without undue discomfort to the patient or major complications.  相似文献   
84.
Sequence diversity in the two barley (Hordeum vulgare L.) genes encoding sucrose synthase I (SSI) and sucrose phosphate synthase II (SPSII), both of which are involved in sucrose accumulation and grain filling, was studied by partial resequencing of eight reference genotypes and SNP analysis by pyrosequencing in a panel of 94 spring and 96 winter European barley varieties. The resequencing was based on two adjacent SSI fragments of size 880 and 820 bp, and a 2,322 bp SPSII fragment. In the SSI gene, 26 SNPs were present in the larger fragment, and 25 in the smaller one, and 11 of these were exploited to develop high-throughput SNP assays used for haplotype analysis. An association analysis based on either a general or a mixed linear model suggested that the predominant three haplotypes influenced certain components of both kernel and malting quality. However, the level of phenotype/haplotype association shown with the SPSII gene was rather low. SNP variation of SSI was used to map the locus to chromosome 7H.  相似文献   
85.
Non-target effects of a bacterial (Pseudomonas fluorescens DR54) and a fungal (Clonostachys rosea IK726) microbial control agent (MCA), on the indigenous microbiota in bulk soil and rhizosphere of barley, and subsequent a sugar beet crop, were studied in a greenhouse experiment. MCAs were introduced by seed and soil inoculation. Bulk and rhizosphere soils were sampled regularly during the growth of barley and sugar beet. The soils were assayed for the fate of MCAs and various features of the indigenous soil microbiota. At the end of the experiment (193 d), DR54 and IK726 had declined by a factor of 106 and 20, respectively, and DR54 showed a short-lasting growth increase in the sugar beet rhizosphere. In general, the non-target effects were small and transient. IK726 seemed to have general stimulating effects on soil enzyme activity and the soil microbiota, and resulted in a significant increase in plant dry weight. The plant growth-promoting effect of DR54 was less pronounced and the DR54 displaced indigenous pseudomonads. DR54 stimulated growth of protozoans with a tolerance for the anti-fungal compound viscosinamide produced by DR54. Treatment with the fungicide Fungazil had no effects on plant growth or soil microorganisms. Phospholipid fatty acid (PLFA) analysis detected the perturbations of the soil microbial community structure in the MCA treatments as well as the return to non- perturbed conditions reflecting the decline of inoculant populations. The PLFA technique appears to be suitable for in situ monitoring of MCA non-target effects on the soil microbiota, but should be combined with assays for MCA survival and soil enzyme activity.  相似文献   
86.
87.
Voyager 2 photography has complemented that of Voyager I in revealing many additional characteristics of Saturn and its satellites and rings. Saturn's atmosphere contains persistent oval cloud features reminiscent of features on Jupiter. Smaller irregular features track out a pattern of zonal winds that is symmetric about Saturn's equator and appears to extend to great depth. Winds are predominantly eastward and reach 500 meters per second at the equator. Titan has several haze layers with significantly varying optical properties and a northern polar "collar" that is dark at short wavelengths. Several satellites have been photographed at substantially improved resolution. Enceladus' surface ranges from old, densely cratered terrain to relatively young, uncratered plains crossed by grooves and faults. Tethys has a crater 400 kilometers in diameter whose floor has domed to match Tethys' surface curvature and a deep trench that extends at least 270 degrees around Tethys' circumference. Hyperion is cratered and irregular in shape. Iapetus' bright, trailing hemisphere includes several dark-floored craters, and Phoebe has a very low albedo and rotates in the direction opposite to that of its orbital revolution with a period of 9 hours. Within Saturn's rings, the "birth" of a spoke has been observed, and surprising azimuthal and time variability is found in the ringlet structure of the outer B ring. These observations lead to speculations about Saturn's internal structure and about the collisional and thermal history of the rings and satellites.  相似文献   
88.
We studied gliadin solubility, surface tension and foam behavior, and the presence of different gliadin types in gliadin aqueous solutions and foams as a function of pH. Gliadin has excellent foaming properties only at neutral and alkaline pH. Its solubility is minimal near neutral pH, while almost complete at acidic and alkaline pH. Surface tensions of gliadin solutions are minimal around neutral pH, higher at alkaline pH, and highest at acidic pH, which corresponds well with their respective foaming properties. Foams at acidic and alkaline pH values are enriched in γ-gliadin, while foams at pH 8.0 have a similar distribution of α- and γ-gliadins. Thus, γ-gliadin predominantly contributes to the foaming properties of gliadin. The poor foaming properties of gliadin at pH 2.0 improve in the presence of 0.25 and 1.0% NaCl. It follows that the presence of positively charged amino acid residues hinders the formation of stable foam at acidic pH.  相似文献   
89.
90.
Abstract

For studies of the effects of seedbed properties on crop emergence, experiments were carried out in shallow plastic boxes. In some experiments, it was examined whether rainfall after sowing could cause oxygen deficiency in the seedbed sufficiently severe to hamper emergence. Crops studied were barley (Hordeum vulgare L.), wheat (Triticum aestivum L.), oilseed rape (Brassica napus var. oleifera, L., Metzg.) and pea (Pisum sativum L.). For harmful oxygen deficiency to develop it appeared that rainfall would need to cause structural collapse of the surface layer followed by continuously wet weather accompanied by slow drainage and high oxygen consumption in the soil; in the experiments the latter was achieved by large amounts of easily decomposable organic matter. It was concluded that such conditions are rare in the field. Therefore, unless rainfall after sowing generates surface water for an extended period, the poor crop emergence often observed after such rainfall is nearly always caused not by oxygen deficiency, but by surface layer hardening when this layer dries.  相似文献   
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