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291.
Objective To develop a technique for placing continuous peripheral nerve block (CPNB) catheters adjacent to palmar nerves in horses and to evaluate the effect of low‐volume local anesthetic (LA) infusion on nociception in the distal equine thoracic limb. Study design In vitro and in vivo laboratory investigation. Study material and animals Forty‐two thoracic limbs from 22 equine cadavers and five horses. Methods Thoracic limb specimens were dissected to find landmarks for catheter insertion adjacent to medial and lateral palmar nerves. Based on the anatomy of the proximal metacarpus, a technique for placing palmar CPNB catheters was developed and the potential for catheter dislodgement studied in vitro by fluoroscopic visualization during passive carpal flexion and dye injection following simulated limb motion. The feasibility of CPNB catheter instrumentation in standing, sedated horses was tested in five animals, with ultrasound control. Electrical and mechanical stimulation thresholds and response latencies for hoof withdrawal responses (HWR) were determined following saline or LA infusion. Results Medial and lateral CPNB catheters were inserted percutaneously 2 and 4–5 cm, respectively, distal to the accessory carpal bone and advanced for ~7 and 10 cm, respectively, to place the tip just proximal to the communicating branch of the nerves. Catheters were placed correctly in 88% and 85% of cadaver limbs. In the standing horses, LA infusion not only increased HWR thresholds and latencies to noxious mechanical or electrical stimulation but also caused vasodilation and limb swelling over time. Conclusion The technique, developed in vitro, for placing and maintaining palmar CPNB catheters in the equine thoracic limb was successfully applied in vivo. Catheters were well tolerated but LA infusion may cause limb swelling, suggesting a need for further exploration of drug and infusion regimens. Clinical relevance Continuous perineural LA infusion along palmar nerves may develop into an effective analgesic technique in horses suffering from lower limb pain.  相似文献   
292.
ABSTRACT

Organic soil amendments such as biochar are increasingly used to improve the fertility of degraded soils and marginal lands, plant growth, water retention and carbon sequestration. The performance of biochar depends on the parent material, the pyrolysis conditions and the nutrient enrichment process, accounting for the variability of the final products. Recently lignite granulates came into focus offering an alternative characterised by homogeneity, vast availability of the raw material and a standardised production process including nitrogen enrichment through oxidative ammonolysis. In a greenhouse experiment the effects of N-modified lignite granulates (NLG) and composted biochar (BC) on the growth of spring wheat (Triticum aestivum) in a sandy, carbon-free substrate were compared. Additionally, the effect of different NLG application rates (5, 7.5, 11, 15, 28 t ha?1) was investigated. Yields as well as nitrogen and water use efficiency of the soil-plant system were determined at the end of the experiment. Both organic amendments increased yields relative to control plants. An increase in yield, nitrogen and water use efficiency for NLG even at low application rates and a better growth performance compared to BC were observed. Present findings, therefore, indicate, that such granulates offer an alternative to existing organic soil amendments.  相似文献   
293.
Abstract

This survey was aimed at comparing the CO2 gas exchange rate of transgenic potato lines and of the isogenic line Désirée in order to establish if genetic modification has resulted in ecologically relevant changes. In examining two transgenic potato lines and one isogenic line, a modular whole-plant cuvette system was implemented for the first time. Furthermore, suitability of such a cuvette system for comparative examination was to be tested in the survey at hand. The lowest CO2 exchange rate was observed in the SST/FFT line. The SST line achieved the highest CO2 exchange rate of all genotypes tested. Measurement of CO2 exchange rate, and additionally collected data on morphologic and characteristics of yield physiology, resulted in distinctly correlating data. The phenotypical changes observed could be classified within the growth and yield profile specified by the German Federal Office of Plant Varieties (Bundessortenamt) for potato varieties permitted for cultivation in Germany. A changed growth rate of crop in the transgenic lines could not be established. A modular whole-plant cuvette system can be implemented in comparative gas exchange measurements in a partly air-conditioned cell.  相似文献   
294.
We compared N fluxes in a 150-year-old Fagus sylvatica coppice and five adjacent 25-year-old plantations of Fagus sylvatica, Picea abies, Quercus petraea, Pinus laricio and Pseudotsuga menziesii. We measured net N mineralization fluxes in the upper mineral horizon (A1, 0–5 cm) for 4 weeks and gross N mineralization fluxes for two days. Gross rates were measured during the 48-h period after addition of 15NH4 and 15NO3. Mineralization was measured by the 15NH4 dilution technique and gross nitrification by 15NO3 production from the addition of 15NH4, and by 15NO3 dilution. Net and gross N mineralization was lower in the soil of the old coppice, than in the plantations, both on a soil weight and organic nitrogen basis. Gross nitrification was also very low. Gross nitrification measured by NO3 dilution was slightly higher than measured by 15NO3 production from the addition of 15NH4. In the plantations, gross and net mineralization and nitrification from pool dilution were lowest in the spruce stand and highest in the beech and Corsican pine stands. We concluded that: (1) the low net mineralization in the soil of the old coppice was related to low gross rate of mineralization rather than to the concurrent effect of microbial immobilisation of mineral N; (2) the absence of nitrate in the old coppice was not related to the low rate of mineralization nor to the absence of nitrifyers, but most probably to the inhibition of nitrifyers in the moder humus; (3) substituting the old coppice by young stands favours nitrifyer communities; and (4) heterotrophic nitrifyers may bypass the ammonification step in these acid soils, but further research is needed to check this process and to characterize the microbial communities.  相似文献   
295.

Background

The diploid, Solanum caripense, a wild relative of potato and tomato, possesses valuable resistance to potato late blight and we are interested in the genetic base of this resistance. Due to extremely low levels of genetic variation within the S. caripense genome it proved impossible to generate a dense genetic map and to assign individual Solanum chromosomes through the use of conventional chromosome-specific SSR, RFLP, AFLP, as well as gene- or locus-specific markers. The ease of detection of DNA polymorphisms depends on both frequency and form of sequence variation. The narrow genetic background of close relatives and inbreds complicates the detection of persisting, reduced polymorphism and is a challenge to the development of reliable molecular markers. Nonetheless, monomorphic DNA fragments representing not directly usable conventional markers can contain considerable variation at the level of single nucleotide polymorphisms (SNPs). This can be used for the design of allele-specific molecular markers. The reproducible detection of allele-specific markers based on SNPs has been a technical challenge.

Results

We present a fast and cost-effective protocol for the detection of allele-specific SNPs by applying Sequence Polymorphism-Derived (SPD) markers. These markers proved highly efficient for fingerprinting of individuals possessing a homogeneous genetic background. SPD markers are obtained from within non-informative, conventional molecular marker fragments that are screened for SNPs to design allele-specific PCR primers. The method makes use of primers containing a single, 3'-terminal Locked Nucleic Acid (LNA) base. We demonstrate the applicability of the technique by successful genetic mapping of allele-specific SNP markers derived from monomorphic Conserved Ortholog Set II (COSII) markers mapped to Solanum chromosomes, in S. caripense. By using SPD markers it was possible for the first time to map the S. caripense alleles of 16 chromosome-specific COSII markers and to assign eight of the twelve linkage groups to consensus Solanum chromosomes.

Conclusion

The method based on individual allelic variants allows for a level-of-magnitude higher resolution of genetic variation than conventional marker techniques. We show that the majority of monomorphic molecular marker fragments from organisms with reduced heterozygosity levels still contain SNPs that are sufficient to trace individual alleles.  相似文献   
296.
297.
To identify native wildlife species possibly susceptible to infection with Schmallenberg virus (SBV), a midge-transmitted orthobunyavirus that predominantly infects domestic ruminants, samples from various free-living ruminants, but also carnivores, small mammals and wild boar were analyzed serologically. Before 2011, no SBV-specific antibodies were detectable in any of the tested species, thereafter, a large proportion of the ruminant population became seropositive, while every sample taken from carnivores or small mammals tested negative. Surprisingly, SBV-specific-antibodies were also present in a large number of blood samples from wild boar during the 2011/2012 and 2012/2013 hunting seasons. Hence, free-ranging artiodactyls may play a role as wildlife host.  相似文献   
298.
In soils, animals and plants from selected sites in the Rustenburg mining area, a part of the South African ore belt, the heavy metal burden was examined. These sites belong to different soil types and are characterized by different land-use (agriculture, grassland). The heavy metal contamination of the soil samples is relatively high and is dominated by chromium and nickel, metals, which are extracted in the mine near the sampling sites. These high heavy metal concentrations had no clear inhibitory influence on micro-organisms or the enzyme activity of soils. It appears that the high clay content of the soils may counteract the influence of heavy metals. On the other hand, tolerant microbial populations may have been established. In addition, the investigated culture plants there was no correlation between the heavy metal content of the soils and the concentrations in roots and shoots. The dangerous, potential contamination of organs in humans seems to be modest, with the exception of tobacco leaves. The heavy metal content of tissues in the examined animals reflect the environmental habitat in situ with no obvious influence on the health of the animals.  相似文献   
299.
Substituted furanilides and furamides show very good activity against Basidiomycetes. Whilst N-cyclohexyl-x-methyl-3-furamides (where x- is one or more of the vacant positions in the furan ring) further substituted on the amide nitrogen have specific activity against Basidiomycetes (e.g. Ustilago nuda, U. scitaminea, Tilletia tritici and Rhizoctonia solani), N-cyclohexyl-N-methoxy-2,5-dimethyl-3-furamide also gives good control of other classes of fungi (e.g. Fusarium nivale and Helminthosporium gramineum). This compound is to be developed under the Code Number BAS 389 F as a mercury-free seed dressing alone or in combination with other fungicides.  相似文献   
300.
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