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Precision Agriculture - The spatial distribution and density of different weed species were monitored during a long-term survey over a period of 9 years on a 5.8 ha arable field...  相似文献   
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Knowledge of the extent of phenotypic variability, genetic diversity and the realized breeding progress is central for the optimum design of breeding programmes, but little information is available for triticale (× Triticosecale Wittmack). In this study, a collection of 885 diverse European triticale lines was evaluated in multilocation field trials in 2 years. We observed significant genotypic variances and high heritabilities for several agronomic and morphological traits and significant correlations among different traits including grain yield. Based on a subset of the population of 121 varieties registered in Europe between 1983 and 2014, we observed a substantial breeding progress for grain yield with a significant rate of increase of 53 kg/ha or 0.67% per year. All lines were genotyped by a genotyping‐by‐sequencing approach yielding 58 888 polymorphic markers. Our analyses revealed the absence of major population structure but a certain grouping of lines according to their origin. Taken together, our results on triticale germplasm and its breeding history provide important information for breeding programmes and future selection gain in this crop.  相似文献   
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A 3-year-old Warmblood gelding was evaluated for intermittent respiratory distress and an inspiratory noise. These signs were mainly observed at exercise but sometimes occurred at rest as well. At the age of 2 months, a severe episode of respiratory distress had necessitated a temporary tracheotomy, which had then healed uneventfully. Examination of the patient and resting endoscopy revealed no structural laryngeal alterations. Exercise endoscopy revealed episodes of active bilateral laryngeal adduction during inspiration. Spirometrically, a corresponding impairment of inspiratory airflow was identified. These abnormalities were most pronounced at the trot but they occurred at magnitudes of inspiratory airflow lower than those inducing dynamic arytenoid collapse in horses with recurrent laryngeal neuropathy. Therefore, the diagnosis of a laryngeal dyskinesia characterised by an active bilateral arytenoid adduction during inspiration was made. No specific treatment was implemented. Three years later, the owner reported that the condition was markedly improved and the horse was used for pleasure riding.  相似文献   
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Proteasomes are the major energy-dependent proteolytic machines in the eukaryotic and archaeal domains of life. To execute protein degradation, the 20S core peptidase combines with the AAA+ ring of the 19S regulatory particle in eukarya or with the AAA+ proteasome-activating nucleotidase ring in some archaea. Here, we find that Cdc48 and 20S from the archaeon Thermoplasma acidophilum interact to form a functional proteasome. Cdc48 is an abundant and essential double-ring AAA+ molecular machine ubiquitously present in archaea, where its function has been uncertain, and in eukarya where Cdc48 participates by largely unknown mechanisms in diverse cellular processes, including multiple proteolytic pathways. Thus, proteolysis in collaboration with the 20S peptidase may represent an ancestral function of the Cdc48 family.  相似文献   
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Root-knot nematodes (RKN) are obligate endoparasites that severely damage the host root system. Nutrient and water uptake are substantially reduced in infested plants, resulting into altered physiological processes and reduced plant growth. The effect of nematode infestation on the morphological changes of roots and subsequent physiological plant responses of infested tomatoes with the RKN Meloidogyne ethiopica was studied in a pot experiment. Plants were infested with two inoculum densities (10 or 50 eggs per cm3 substrate) and its effect was evaluated 74 and 102 days post inoculation (DPI). Morphological changes and root growth was determined by analysing scanned images of the whole root system. Nematode infestation reduced the portion of fine roots and increased that of coarse roots due to gall formation. Fine roots of non-infested control plants represented around 51% of the area of the whole root system at 74 and 102 DPI. In comparison to controls, plants inoculated with low and high nematode density had 2.1 and 3.2-times lower surface area of fine roots at 102 DPI. Root analyses revealed that plants had a very limited ability to mitigate the effects of the root-knot nematodes infestation by altering root growth. Root galls had a major influence on the hydraulic conductivity of the root system, which was significantly reduced. The low leaf water potential of infested plants coincided with decreased stomatal conductivity, transpiration and photosynthesis. The latter two were reduced by 60–70% when compared to non-infested control plants.  相似文献   
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Purpose X-linked juvenile retinoschisis (XLRS) is the most common juvenile maculopathy in men and is caused by mutations in the gene encoding retinoschisin (RS1). Evidence in the literature on the therapeutic effect of carboanhydrase inhibitors (CAIs) to treat schisis formation in the retina has remained equivocal. Here, we evaluate the effect of the CAI dorzolamide on the structural and functional disease progression in the mouse model for XLRS (Rs1h(-/y) ). Methods Rs1h ( -/y ) mice were treated unilaterally with dorzolamide eye drops (Trusopt(?) 20?mg/mL) every 12?h for 2?weeks starting on postnatal day 14 (n?=?27). Changes of retinal structure were monitored by confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography 12?h, 14?days, 4?weeks, 2?months, and 6?months after completion of the treatment. Results Schisis formation (peak at 3?months) preceded photoreceptor degeneration and hyper-fluorescence (peak at 7?months). Structural pathology was most severe in the superior hemi-retina with previously unreported hyper-fluorescent lesions. Quantitative analysis showed no significant differences regarding the inner or outer retinal thickness of the treated vs. untreated eyes 12?h after the completion of treatment (IRT(12?h) =?-1.29?±?1.89?μm; ORT(12?h) =?0.61?±?2.08?μm; mean?±?95%CI) or at any later time point. Conclusion Time line analysis after short-term treatment with CAI failed to show short-, intermediate-, or long-term evidence of structural improvement in Rs1h(-/y) mice. Schisis formation in the inner retina peaked at the age of 3?months and was followed by photoreceptor degeneration predominantly in the superior hemi-retina. Previously unreported hyper-fluorescent lesions co-register with structural retinal pathologies.  相似文献   
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As West Nile virus (WNV) can cause lethal diseases in raptors, a vaccination prophylaxis of free-living and captive populations is desirable. In the absence of vaccines approved for birds, equine vaccines have been used in falcons, but full protection against WNV infection was not achieved. Therefore, two DNA vaccines encoding the ectodomain of the envelope protein of WNV lineages 1 and 2, respectively, were evaluated in 28 large falcons. Four different vaccination protocols were used, including electroporation and booster-injections of recombinant WNV domain III protein, before challenge with the live WNV lineage 1 strain NY99. Drug safety, plasmid shedding and antibody production were monitored during the vaccination period. Serological, virological, histological, immunohistochemical and molecular biological investigations were performed during the challenge trials. Antibody response following vaccination was low overall and lasted for a maximum of three weeks. Plasmid shedding was not detected at any time. Viremia, mortality and levels, but not duration, of oral virus shedding were reduced in all of the groups during the challenge trial compared to the non-vaccinated control group. Likewise, clinical scoring, levels of cloacal virus shedding and viral load in organs were significantly reduced in three vaccination groups. Histopathological findings associated with WNV infections (meningo-encephalitis, myocarditis, and arteritis) were present in all groups, but immunohistochemical detection of the viral antigen was reduced. In conclusion, the vaccines can be used safely in falcons to reduce mortality and clinical signs and to lower the risk of virus transmission due to decreased levels of virus shedding and viremia, but full protection was not achieved in all groups.  相似文献   
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