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51.
Information is presented on new occurrences of two homopteran pests,Matsucoccus josephi Bodenheimer et Harpaz (Matsucoccidae) andPineus pini (Macquart) (Adelgidae), in Israel, Jordan and southern Lebanon.M. josephi occurs in Israel in almost all natural relicts of Aleppo pine (Pinus halepensis). It infests all plantations of Aleppo pine, brutia pine (Pinus brutia ssp.brutia) and Eldar pine (P. brutia ssp.eldarica) north of 31°12′ lat. N. Heavy damage has been observed in the Judean Foothills, Judean Mts. and northern Samaria.M. josephi and its specific predator,Elatophilus hebraicus Pericart (Hemiptera: Anthocoridae), are recorded for the first time in Jordan and southern Lebanon. The scale was found in all visited Aleppo pine and brutia pine stands in Jordan and in natural and planted brutia pine in southeastern Lebanon. Damage byM. josephi in Jordan was observed only in young plantations of Aleppo pine; in Lebanon no signs of injury were recorded.P. pini was found for the first time in Jordan, where it causes severe damage to young stands of Aleppo pine and stone pine (Pinus pinea). Contribution from the Agricultural Research Organization. No. 1225-E, 1993 series.  相似文献   
52.
We collected acorns from selected Quercus robur and Quercus petraea mother trees growing at stations with different depths to the water table. We produced pairs of micro-cuttings from these single acorns. The obtained pairs of cuttings represented phenotypes of high similarity according to photosynthetic parameters. These pairs of cuttings were used to test the plasticity of response to contrasting water regimes. For each pair, one cutting was submitted to drought and the other was submitted to waterlogging. Drought response was recorded according to gas exchange traits (stomatal closure and water use efficiency). The response to waterlogging was recorded according to the capacity to form hypertrophied lenticels and to maintain the CO2 assimilation rate. Intermediary phenotypes presenting both high water use efficiency and the capacity to develop hypertrophied lenticels were expected.  相似文献   
53.
The objective of this study was to evaluate the efficacy of a vaccine in the prevention of Giardia duodenalis infection in calves. Six 2-week old calves were vaccinated subcutaneously with a sonicated G. duodenalis trophozoite vaccine. Six 2-week old control calves received a subcutaneous injection of sterile phosphate-buffered-saline mixed with adjuvant. Injections were repeated after 28 days. Eleven days after the second injection, calves were challenged orally with 1x10(5) purified G. duodenalis cysts from a naturally infected calf. Throughout the study, fecal samples were collected at regular intervals and examined for the presence of G. duodenalis cysts. Blood samples were collected weekly until G. duodenalis challenge and bi-weekly following challenge. Calves were euthanized 14 days after challenge and G. duodenalis trophozoites within the small intestines were enumerated. Serum antibody titers were significantly higher in vaccinated compared to non-vaccinated calves. Vaccinated calves tended to excrete more G. duodenalis cysts in their feces than non-vaccinated calves. The number of trophozoites in the small intestine was not different between vaccinated and non-vaccinated calves. Changes consistent of moderate enteritis were found in the intestines of one vaccinated and one non-vaccinated calf. Despite a serological immune response following vaccination, this vaccine was not efficacious in preventing giardiasis or reducing cyst shedding in calves.  相似文献   
54.
Phenolics from grapes and wines can play a role against oxidation and development of atherosclerosis. Stilbenes have been shown to have cancer chemopreventive activity and to protect lipoproteins from oxidative damage. A method for the direct determination of stilbene oligomers (viniferin and pallidol) as well as astilbin in different types of wine using high-performance liquid chromatography with UV detection is described. In a survey of 21 commercial wines from the south of France, levels of pallidol and viniferin are reported for the first time in different types of wines. Viniferin was found to be present only in red and botrytized sweet white wines with levels between 0.1 and 1.63 mg/L; pallidol was not found in dry and sweet white wines but only in wines made by maceration with stems, with levels between 0.38 and 2.22 mg/L. Highest levels of astilbin were found in Egiodola (15.13 mg/L), Merlot (11.61 mg/L), and Cabernet Sauvignon (8.24 mg/L) for red wines and in Sauvignon (5.04 mg/L) for white varietal wines. Astilbin levels are highest for recent vintages, but pallidol is not found in older vintages. During noble rot development in Sauvignon or Sémillon grapes from the Sauternes area, levels of trans-astringin, trans-resveratrol, trans-piceid, and pallidol are quite low (<0.5 mg/kg of grapes). Viniferin and astilbin levels become optimum at 2 and 30 mg/kg, respectively, during spot grape and speckle grape stages.  相似文献   
55.
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   
56.
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   
57.
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   
58.
59.

Purpose

Changes in the chemical conditions of sediment following a resuspension event might lead to release of sequestered pollutants. In the present study, arsenic (As) and iron (Fe) speciation were investigated before and after such an event, in sediment from L'Estaque marina (France). This marina is located near an industrial plant which processed As-bearing ores for several decades.

Materials and methods

Cores (0–60 cm) and surface sediment (0–10 cm) were collected by a diver. Sediment properties along the length of the core were determined by coupling chemical extractions, and diffraction (i.e., X-ray diffraction) and spectroscopic techniques (i.e., micro-X-ray fluorescence, scanning electron microscopy coupled with energy dispersive spectroscopy, Raman spectroscopy, and X-ray absorption near-edge spectroscopy). Laboratory experiments mimicking resuspension and resettlement events were conducted over a period of 3 months in both biotic and abiotic (autoclaved) conditions. In both cases, oxidation proceeded by oxygen diffusion from the top to the bottom of the sediment.

Results and discussion

It was demonstrated that the unperturbed sediment was anoxic. Arsenic, almost fully under its trivalent As(III) form, had a concentration between 194 and 473 μg g?1, and its main carrier phase was the Fe-monosulfide mackinawite; this mineral originated from in situ transformation of Fe oxides, partly emitted by the industrial plant. The observed progressive pyritisation of mackinawite was not accompanied by further reduction of As which means that As remained bound to mackinawite, as incorporation into the pyrite lattice would require that it reduced to its (?I) oxidation state. After oxidation during the resuspension event, and in abiotic conditions, As was fully pentavalent As(V) in the oxidized zone of the re-settled sediment. On the contrary, in the biotic experiment, the development of a bacterial mat, which consumed oxygen for respiration processes, preserved the sediment from total oxidation. Consequently, As was present under both As(III) and As(V) forms, the first one being minor (~20 % of total As) in the top of the sediment. The diversity of aioA genes was large, and was similar in the oxidized layer and the deeper black-colored sediment.

Conclusions

These results indicate that biological processes partly control the in situ geochemical system by inducing low redox areas in theoretically oxidized sediments.  相似文献   
60.
In the Krui arae, (South Sumatra, Indonesia), the damar agroforests (Shorea javanica, Dipterocarpaceae) are but one element of the farming systems which include several other cropping systems such as irrigated or rainfed rice cultivation, and coffee plantation.Rainfed rice is cultivated in forest clearings, in order to meet rice requirements which cannot be met with irrigated rice crop only. In the forest clearings, coffee stands are established in rice crop, and later, Damar are planted among coffee plants. As a result of this cropping system, the damar agroforest spreads while the forest dwindles.In one village, no more forest land is available for peasants' clearings. The resulting high land pressure causes cropping systems and farming systems to change or to be exported to neighbouring areas where forest land is still available.
Résumé Les agroforêts à damar (Shorea javanica) ne sont qu'un élément du système d'exploitation agricole de la région de Krui, Sud Sumatra, Indonésie. Ceux-çi associent plusieurs systèmes de culture tels que la riziculture irriguée, la culture du riz pluvial et la plantation de cafeiérs.L'insuffisance des surfaces en rizières irriguées est compensée par la culture du riz pluvial, pratiquée en ladang, parcelle de forêt défrichée et brûlée. Sur les ladangs se succèdent les cultures de riz, de café puis de damar, transformant ainsi la forêt naturelle en agroforêt à damar. On assiste à l'extension continue des agroforêts au détriment de la forêt naturelle.Dans un des villages étudiés, la réserve de terres forestières communales est épuisée, déjà transformée en agroforêts. La forte pression fonçière qui en résulte induit des transformations dans les systèmes de production agricole ou incite des agriculteurs à migrer dans des régions voisines encore riches en terres forestières. Dans ces régions, les migrants reproduisent un système agroforestier très proche de celui de Krui, dans la mesure où les conditions écologiques le permettent.
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