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111.
The factors responsible for the clinical progress of visceral leishmaniasis (VL) in dogs have not been yet established. The starting hypothesis was the possibility of associating the changing level of a specific type of cytokines with the evolution of the infection towards infection-manifested disease or resistant behaviour. For this purpose the authors have established a connection between Leishmania load, cytokine mRNA accumulation, and the progression of the disease in naturally infected asymptomatic dogs. We made use of real-time (RT) PCR system to detect the expression of cytokine mRNA levels during all the phases of the infection. In particular, we measured the amount of parasites in samples such as blood, lymph nodes and skin, and the expression levels of IFN-gamma, IL-2, IL-4, IL-10, IL-12 and IL-18 cytokines in the blood. We employed different targeted real-time PCR assay on 40 naturally infected dogs, initially asymptomatic; 20 of these progressed to overt disease, and the 20 remaining dogs remained asymptomatic throughout the period of study (2 years). Two other groups included: 20 naturally infected dogs with clinical signs of VL, and 20 healthy dogs living in a non-endemic area. All these animals were employed as positive and negative controls, respectively. The overall results obtained demonstrate that the simultaneous evaluation of parasites and cytokine levels represents a reliable tool for predicting disease development, and thus for choosing the best treatment for the asymptomatic form of the disease.  相似文献   
112.
The occurrence of ichthyosis in two Italian Chianina calves is described for the first time. Both animals, affected by ichthyosis fetalis and ichthyosis congenita, respectively, showed diffuse cutaneous thickening which had been present since birth. The first patient was a three-month-old female calf; inelastic leather cuirass-like skin associated with generalized hypotrichosis and local alopecia, delay of the physiologic change of coat colour, stiff movement and growth retardation were the most prominent clinical characteristics. The patient was kept under observation for almost one year. The second case occurred in a 18-day-old female calf which was referred to our clinic after it had already died; the presence of irregular hyperkeratotic plates separated by deep fissures over the entire cutaneous surface and the slight eversion of the mucocutaneous junction (eclabium and ectropion) were the most characteristic alterations. In both cases, the major histopathological feature was a diffuse lamellar orthokeratotic hyperkeratosis. An underlying genetic defect was strongly suspected on the basis of a common ancestor for the two sires of the affected calves and of the current scientific knowledge.  相似文献   
113.
The authentication of the conditions of animal production, based on the analysis of meat commercial cuts, is a major challenge on both societal and analytical grounds. The aim of the present work was to propose a method for the extraction of the volatile compounds from ruminant raw muscles trimmed of fat and to assess by mass spectrometry-based techniques the relevance of these compounds for the authentication of the type of feeding offered to the animals. The first step of the study consisted of validating conditions of dynamic headspace (DH) extraction of volatile compounds that enabled us to minimize the appearance of heat-induced artifacts and to maximize the richness of the DH-gas chromatography-mass spectrometry profile (DH-GC-MS) of raw lamb muscle. An extraction temperature of 35 degrees C (vs 60 and 90 degrees C) and a sample mass of 6.25 g (vs 12.5, 25, and 50 g) were shown to be suitable. The second step aimed at identifying volatile compounds enabling us to discriminate muscle samples from 16 experimental lambs fed either concentrate (n = 8) or pasture (n = 8). Before, to carefully explore the information given by the DH-GC-MS signal, the MS spectra acquired along the chromatogram were summed and then converted in a virtual-DH-MS spectral fingerprint to have a quick overview of the discriminative potential of the volatile fraction. According to univariate (analysis of variance) and to multivariate (principal component analysis) data treatments performed on virtual-DH-MS fingerprints, the meat volatile fraction was relevant to reveal the type of feeding of the living animal. The detailed examination of the information given by the GC dimension showed that 33 volatile compounds among the 204 detected in the muscle by DH-GC-MS enabled us to discriminate the type of feeding of the lambs. The relevance of these results is discussed in light of previous studies performed on adipose tissues.  相似文献   
114.
Essential oil (EO) from aerial parts (leaves, juvenile branches, and flowers when present) of Pistacia lentiscus L. growing wild in five localities of Sardinia (Italy) was extracted by steam-distillation (SD) and analyzed by gas chromatography (GC), FID, and GC-ion trap mass spectrometry (ITMS). Samples of P. lentiscus L. were harvested between April and October to study the seasonal chemical variability of the EO. A total of 45 compounds accounting for 97.5-98.4% of the total EO were identified, and the major compounds were alpha-pinene (14.8-22.6%), beta-myrcene (1-19.4%), p-cymene (1.6-16.2%), and terpinen-4-ol (14.2-28.3%). The yields of EO (v/dry w) ranged between 0.09 and 0.32%. Similar content of the major compounds was found in samples from different origins and seasonal variability was also observed. The EOs were tested for their antifungal activity against Aspergillus flavus, Rhizoctonia solani, Penicillium commune, Fusarium oxysporum. Two samples were weakly effective against Aspergillus flavus. Furthermore, terpinenol and alpha-terpineol, two of the major components of EO of Pistacia lentiscus L., totally inhibited the mycelian growth of A. flavus. Quite good antioxidant activity of the EO was also found.  相似文献   
115.
Land-use changes have strong impacts on biological communities. Among them, land abandonment is threatening a large number of conservation-concern species associated with semi-natural habitats shaped by ‘traditional’ farming. We focused on the red-backed shrike as a model for investigating the effect of land abandonment on a threatened bird species, and used historical data to model dynamic scenarios. We explored variations in habitat suitability from the 1950s to the present and predicted possible future variations. After investigating local habitat preferences of the species, we formulated a spatially explicit model of habitat suitability for shrikes according to current land-use types; then, we evaluated past habitat suitability, by applying the model to three known past scenarios, and simulated the habitat changes after land abandonment. By combining a habitat-association approach with past and future land use scenarios, we assessed and predicted the effects of habitat changes caused by abandonment. Shrike occurrence was favoured by the cover of four types of grassland and of shrubland with trees, and negatively affected by broadleaved woodlands. The current average habitat suitability is less than half of what it was in the 1950s. Future predictions in a complete abandonment scenario suggest that important decrease could be expected 10 or 20 years after abandonment, and that after 30 years the red-backed shrike would be completely extinct. Alternative scenarios involving partial abandonment suggested that subsidy policies may mitigate the effects of abandonment. Knowing land-use dynamics allowed the exploration of effects of land-use changes and corroborated the importance of low-intensity farming for conservation.  相似文献   
116.
Large quantity of dehydrated oil sludge, generated in the disposal process of oil-containing sewage in Shengli oilfield, needs to be rendered harmless to human and to the environment. Bioremediation has been accepted as an important method for the treatment of oil sludge by employing indigenous or extraneous microbial flora. The bioremediation of a dehydrated oil sludge of 960 m3 in volume was carried out in a prepared bed in Binyi oil-containing sewage disposal station, Shengli oil fields, China. Four different treatments were made to study the impact of certain process parameters on the bioremediation efficiency. Of the oil contaminants, 52.75% was degraded within 160 days when treated in a greenhouse, while the oil contaminations decreased by only 15.46% in the untreated sludge. The variations of the physical and chemical properties of oil sludge, the amount and the functional diversity of microorganisms in sludge were characterized. The results indicated that the water-holding capacity of oil sludge, the amount and the metabolism functional diversity of microorganisms in sludge in the three treatments increased markedly compared with the control.  相似文献   
117.
Hypertension development in the spontaneously hypertensive rat (SHR) leads to vascular wall widening by smooth muscle cell proliferation. In these cells, triglycerides (TG) and cholesteryl esters (CE) can accumulate until they become foam cells. We administrated two oleic rich oils, virgin olive (VOO) and high oleic sunflower oils (HOSO), to Wistar-Kyoto rats (WKY) and SHR because these oils have been reported to reduce the risk for coronary heart disease in hypertensive patients and SHR. After 12 weeks of feeding, we analyzed the TG and CE composition and the lipolytic (lipoprotein lipase, LPL, and non-LPL) activity in aortas of these animals. HOSO increased the content of linoleic acid in CE and TG of aortas from both WKY and SHR as compared with animals fed VOO by proportionally decreasing the content of oleic acid. Conversely, VOO reduced the LPL and non-LPL lipolytic activities, hence limiting the free fatty acids available for the synthesis of TG and CE in the vascular wall.  相似文献   
118.
The chemical composition of the essential oil of the Sardinian Rosmarinus officinalis L. obtained by hydro distillation and steam\hydro distillation was studied using GC-FID and MS. Samples were collected at different latitude and longitude of Sardinia (Italy). The yields ranged between 1.75 and 0.48% (v/w, volume/dry-weight). A total of 30 components were identified. The major compounds in the essential oil were alpha-pinene, borneol, (-) camphene, camphor, verbenone, and bornyl-acetate. Multivariate analysis carried out on chemical molecular markers, with the appraisal of chemical, pedological, and random amplified polymorphic DNA data, allows four different clusters to be distinguished. The antimicrobial and antifungal tests showed a weak activity of Sardinian rosemary. On the other hand, an inductive effect on fungal growth, especially toward Fusarium graminearum was observed.  相似文献   
119.
120.
Cryopreservation of gametes and embryos is used to maintain genetic diversity of domestic and wild felids. However, felid oocytes and preimplantation embryos contain large amount of intracellular lipids, which affect their cryosensitivity. The objective was to compare the effects of slow freezing and vitrification and to study lipid phase transition (LPT) during cooling in cat embryos. In vitro-derived embryos were cultured 48 hr up to 4–8 cell stage, thereafter were either slow frozen or vitrified. Propylene glycol (PG) alone was used as a cryoprotective agent (CPA) for slow freezing, and a mixture of PG and dimethyl sulfoxide (DMSO) were used as CPAs for vitrification. After thawing/warming, embryos were in vitro cultured additionally for 72 hr. The total time of in vitro culture was 120 hr for all the groups including non-frozen controls. Effects of both cryopreservation procedures on the subsequent embryo development and nuclear fragmentation rate in embryonic cells were compared. There was no significant differences among the percentages of embryos achieved morula and early blastocyst stage in frozen-thawed group (36.4% and 20.0%), in vitrified-warmed group (34.3% and 28.6%) and in controls (55.6% and 25.9%). Cell numbers as well as nuclear fragmentation rate did not differ in these three groups. Average lipid phase transition (LPT) temperature (T*) was found to be relatively low (–2.2 ± 1.3°C) for the domestic cat embryos. It is supposed that the low LPT of LDs may provide a good background for successful application of slow freezing to domestic cat embryos. Generally, our study indicates that slow freezing and vitrification are both applicable for domestic cat embryo cryopreservation.  相似文献   
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