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61.
Prevalence of Giardia duodenalis in dairy and beef cattle on farms around Charlottetown, Prince Edward Island (Canada) was determined by analyzing feces using direct immunofluorescence antibody microscopy. Genotypes were determined by 16S-rRNA sequencing. Fecal samples (n = 892) were collected from adult cattle in dairy tie-stall, dairy free-stall, and beef herds (10 herds each), and from calves (n = 183) from 11 dairy farms. Prevalence rates were 38% and 51% in cows and calves, respectively. Giardia duodenalis was present in all dairy herds, in 9/10 beef herds and in calves from 10/11 herds examined. Prevalence rates were 40% and 41% for cows in tie- and free-stall herds, respectively, and 27% for beef cows. Zoonotic Assemblage A was found in 12.2% of calves concomitantly infected with Assemblage E. All successfully sequenced samples (114/128) from cows corresponded to Assemblage E. Giardia duodenalis is highly prevalent in cattle herds in Prince Edward Island and Assemblage A in calves is a potential public health concern.  相似文献   
62.
Although menthol is a common ingredient used in food products, other molecules also evoke coolness through stimulation of the somatosensory system. To discover new molecules having cooling properties, we virtually screened the chemical structures of terpenes and sesquiterpenes to find structures that are similar to (-)-menthol. We realized that dihydroumbellulols could be good candidates. Although their occurrence was reported in Hyptis pectinata Poit, we were unable to obtain these molecules from the plant or to prove their natural occurrence. Therefore, we extracted (-)-(R)-umbellulone from Umbellularia californica Nutt. The (-)-(R)-umbellulone was reduced to prepare (1R,2R/S)-1-isopropyl-4-methylbicyclo[3.1.0]hex-3-en-2-ol, (1R,4R/S)-1-isopropyl-4-methylbicyclo[3.1.0]hexan-2-one, and (1R,2RS,4RS)-1-isopropyl-4-methylbicyclo[3.1.0]hexan-2-ols, named dihydroumbellulols. Sensory analysis suggested that (1R,2R,4S)-dihydroumbellulol has a pleasant, trigeminal cooling effect, about 2-3 times less cooling than (-)-menthol, with a weak odor slightly reminiscent of eucalyptol. In addition, a previously unreported compound was discovered, (-)-(1R)-1-isopropyl-4-methylenebicyclo[3.1.0]hexan-2-one.  相似文献   
63.
One of the objectives of the malting industry is to reduce the energy cost during kilning without major effect on malt quality. In this study, the impact of a low hydration steeping process on lipid transfer protein (LTP1) modifications and β-glucan breakdown was evaluated in low (LH) and high (HH) hydrated malts. LTP1 modifications analyzed by MS/MS revealed acylation, glycation, and disulfide bond breakage in both LH and HH malts. LTP1 free amine content measurement and fluorescence of Maillard protein adducts revealed no significant difference between LH and HH malts. Immunolabeling of LTP1 during malting highlighted the diffusion of the protein from the aleurone layer to the endosperm at the end of steeping in both LH and HH malts. By contrast, a significant higher amount of β-glucans was measured in LH malts after five days of germination, whereas no significant difference between LH and HH malts was revealed through immunostaining of β-glucans or evaluation of the endosperm integrity after seven days of germination. The possibility to reduce the effects of a low hydration steeping process on β-glucan hydrolysis by increasing germination time was discussed.  相似文献   
64.
EIA (Equine Infectious Anemia) is a blood-borne disease primarily transmitted by haematophagous insects or needle punctures. Other routes of transmission have been poorly explored. We evaluated the potential of EIAV (Equine Infectious Anemia Virus) to induce pulmonary lesions in naturally infected equids. Lungs from 77 EIAV seropositive horses have been collected in Romania and France. Three types of lesions have been scored on paraffin-embedded lungs: lymphocyte infiltration, bronchiolar inflammation, and thickness of the alveolar septa. Expression of the p26 EIAV capsid (CA) protein has been evaluated by immunostaining. Compared to EIAV-negative horses, 52% of the EIAV-positive horses displayed a mild inflammation around the bronchioles, 22% had a moderate inflammation with inflammatory cells inside the wall and epithelial bronchiolar hyperplasia and 6.5% had a moderate to severe inflammation, with destruction of the bronchiolar epithelium and accumulation of smooth muscle cells within the pulmonary parenchyma. Changes in the thickness of the alveolar septa were also present. Expression of EIAV capsid has been evidenced in macrophages, endothelial as well as in alveolar and bronchiolar epithelial cells, as determined by their morphology and localization. To summarize, we found lesions of interstitial lung disease similar to that observed during other lentiviral infections such as FIV in cats, SRLV in sheep and goats or HIV in children. The presence of EIAV capsid in lung epithelial cells suggests that EIAV might be responsible for the broncho-interstitial damages observed.  相似文献   
65.
Abstract The objective of this multicentre, parallel, blinded, randomized controlled study was to evaluate the efficacy and the safety of cyclosporine (CsA group, 117 dogs) in comparison with methylprednisolone (MP group, 59 dogs) in the treatment of atopic dermatitis for 4 months. Mean induction dose of both drugs (5 mg/kg CsA, 0.75 mg/kg MP) was tapered over time according to the clinical response. At the end of the study, the mean estimated percentage reduction from baseline (confidence interval) of lesion scores was 52% (44–59) and 45% (35–56), and the reduction in pruritus score was 36% (27–43) and 33% (23–43) in dogs in the CsA and MP groups, respectively. These percentages were not significantly different between groups. A significantly better overall assessment of efficacy was obtained in the CsA-treated dogs (76 vs. 63% responses excellent or good in the CsA compared with MP group). CsA-treated dogs presented a higher frequency of gastrointestinal disorders, mainly vomiting, but MP dogs tended to be more susceptible to infections. There was no remarkable change over baseline of the haematological and biochemical parameters in the two groups.  相似文献   
66.
Ophelimus maskelli (Ashmead) (Hymenoptera: Eulophidae), an invasive species in the Mediterranean area that occurs naturally onEucalyptus camaldulensis at Wagga Wagga in New South Wales, was studied in Israel on the same host plant. The most distinctive characteristic ofO. maskelli as compared with other congeners is the presence of only a single seta on the submarginal vein.O. maskelli shows a clear tendency to oviposit in developed, immature leaves, and it prefers to oviposit on an area of the leaf blade near the petiole. The female lays an average of 109 eggs when maintained on water alone. The egglaying distribution tended towards aggregation, and the same tendency has also been observed within and among trees. The wasp prefers to attack the lower canopy. The gall diameter ranged from 1.2 to 0.9 mm, and gall density from 11.5 to 36.0 galls cm−2, respectively. The typical color of the gall appeared as soon as third instar larva developed. Galls on shaded leaves remained green or greenish-yellow, whereas those that were exposed to the sun were reddish.O. maskelli produces three generations per year in Israel. High flight occurs among the spring generations, starting in early March. The wasps were attracted to green sticky plates much more than to the other tested colors. Heavy galling byO. maskelli results in premature shedding of the leaves, soon after the emergence of the wasps. Among the 84 eucalyptus species tested, the following 14 species were found to be suitable hosts:E. botryoides, E. bridgesiana, E. camaldulensis, E. cinerea, E. globulus, E. gunii, E. nicholii, E. pulverulenta, E. robusta, E. rudis, E. saligna, E. tereticornis andE. viminalis. This study focused on morphological and development characters that can clearly distinguishO. maskelli fromOphelimus eucalypti Gahan, and on examining the effect of crossing between eucalyptus species on the development possibilities of the wasps. Also considered were the effect of the food on adult survival, the competition between the eulophid gall makerLeptocybe invasa Fisher & LaSalle andO. maskelli, the heavy damage inflicted on eucalyptus, and the health problems and nuisance to people caused by the wasp near heavily infested trees during the mass emergence of adults. http://www.phytoparasitica.org posting Dec. 5, 2006.  相似文献   
67.
There is an amazing diversity of cell wall composition and cell wall polysaccharide structure in wheat grain that is only partly explained by the complexity of plant tissues and cell type functions present in this organ. This review presents the state of the art on the structure and diversity of cell wall polymers in mature wheat grain and recent knowledge on cell wall metabolism with a focus on development-associated changes in wheat grain cell wall polysaccharides and genes controlling their biosynthesis. The diversity of polysaccharide structure observed in endosperm cell walls is tentatively explained on the basis of polysaccharide properties and cell type function.  相似文献   
68.
Blooms of the benthic toxic dinoflagellate genus Ostreopsis have been recorded more frequently during the last two decades, particularly in warm temperate areas such as the Mediterranean Sea. The proliferation of Ostreopsis species may cause deleterious effects on ecosystems and can impact human health through skin contact or aerosol inhalation. In the eastern Atlantic Ocean, the toxic O. cf. ovata has not yet been reported to the north of Portugal, and the only species present further north was O. cf. siamensis, for which the toxic risk is considered low. During summer blooms of unidentified Ostreopsis species on the French Basque coast (Atlantic) in 2020 and 2021, people suffered from irritations and respiratory disorders, and the number of analyzed cases reached 674 in 2021. In order to investigate the causes, sampling was carried out during summer 2021 to (i) taxonomically identify Ostreopsis species present using a molecular approach, (ii) isolate strains from the bloom and culture them, and (iii) characterize the presence of known toxins which may be involved. For the first time, this study reports the presence of both O. cf. siamensis and O. cf. ovata, for which the French Basque coast is a new upper distribution limit. Furthermore, the presence of ovatoxins a, b, c, and d in the environmental sample and in a cultivated strain in culture confirmed the toxic nature of the bloom and allowed identifying O. cf. ovata as the producer. The present data identify a new health risk in the area and highlight the extended distribution of some harmful dinoflagellates, presumably in relation to climate change.  相似文献   
69.
Mycoplasma synoviae infection occurs worldwide in commercial poultry flocks and may result in severe economic losses. The prevalence of this mycoplasma in standard layers older than 60 weeks was studied in a French department and the characteristics of infected or free flocks were compared. The genomic profiles of isolates from 36 infected flocks were studied by pulsed-field gel electrophoresis and random amplified polymorphic DNA methods in order to investigate possible routes of transmission. The minimum inhibitory concentrations of antibiotics were determined. Results showed that infection was more frequent in multi-age farms. Egg production and mortality of infected flocks were respectively lower and higher than in non-infected flocks but the differences were not statistically significant. The genomic profiles of isolates were quite homogeneous, a feature which does not facilitate the understanding of routes of transmission. All isolates were susceptible to tetracyclines, macrolides (except erythromycin), spectinomycin and fluoroquinolones.  相似文献   
70.

Purpose

Soil compaction resulting from mechanisation of forest operations reduces air permeability and hydraulic conductivity of soil and can result in the development of hydromorphic and/or anoxic conditions. These hydromorphic conditions can affect physico-chemical properties of the soils. However, early detection of these effects on mineralogical portion of soils is methodologically difficult.

Materials and methods

To analyse the effects of soil compaction on iron minerals in loamy Luvisol, three compacted and three non-compacted soil profiles up to the depth of 50 cm were collected from an artificially deforested and compacted soils after 2 years of treatment. Soil was compacted with the help of 25 Mg wheeler’s load to increase the dry bulk density of soil from 1.21?±?0.05 to 1.45?±?0.1 g cm?3. Soil samples were analysed by X-ray diffraction (XRD) and were treated by citrate bicarbonate (CB) and dithionite citrate bicarbonate (DCB) under controlled conditions. Major and minor elements (Fe, Al, Mg, Si and Mn) were analysed by ICP-AES in the CB and DCB extracts.

Results and discussion

It was found that X-ray diffraction is not an enough sensitive method to detect the quick mineralogical changes due to soil compaction. Results obtained from CB-DCB extractions showed that soil compaction resulted in larger CB and smaller DCB extractable elements as compared to non-compacted soil. Labile Fe was found 30 % of total Fe oxides in compacted soil against 10–14 % in non-compacted soils. Compaction thus resulted in Fe transfer from non-labile to labile oxides (s.l.). Results showed that soil compaction leads to the reduction of Fe3+ to Fe2+. The effects of hydromorphic conditions due to soil compaction were observed up to the depth of 35 cm in forest soil profile. Furthermore, a close association of Al with Fe oxides was observed in the soil samples, while Mn and Si were mainly released from other sources, Mg showing an intermediate behaviour.

Conclusions

Hydromorphic conditions owing to soil compaction affect the mobility and crystallisation process of iron mineral. CB-DCB selective extraction technique, in contrast to XRD technique, can be effectively used to examine the possible effects of soil compaction on iron minerals.
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