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Not much is known about IBDV-pathogenesis and immune mechanisms following in ovo vaccination. In this study, we compared the immunopathogenesis of an intermediate IBDV-vaccine in post-hatch- and in ovo-inoculated chickens. In ovo-vaccinated birds recovered significantly faster from lesions of the bursa of Fabricius than post-hatch vaccinated (P<0.05). A significant accumulation of intrabursal CD8(+) T cells was observed in post-hatch but not in in ovo-vaccinated chickens (P<0.05). The innate immunity was comparable between in ovo- and post-hatch-vaccinated groups as indicated by comparable intrabursal macrophage accumulation and intrabursal IBDV-clearance. Overall, our observations indicate that IBDV in ovo vaccination may be advantageous over post-hatch. In ovo-vaccinated birds recover faster from bursa lesions and exhibit similar protection against challenge in comparison to post-hatch vaccinated.  相似文献   
43.
Avian pneumovirus (APV) causes a respiratory disease in turkeys. The virus has been associated with morbidity and mortality due to secondary infections. Our objective was to determine if APV caused immunosuppression in the T-cell or B-cell compartments and to study the pathogenesis of the disease in APV maternal antibody-lacking 2-wk-old commercial turkeys. APV was administered by the eyedrop/intranasal route. Observations were made for gross lesions, viral genome, and T-cell mitogenesis and cytokine secretion at 3, 5, 7, 14, and 21 days postinoculation (DPI). During the acute phase of the disease that lasted for about 1 wk, the turkeys exposed to APV showed clinical signs characterized by nasal discharge and sinus swelling. Virus genome was detected by in situ hybridization in cells of turbinates and trachea at 3 and 5 DPI. At 3 and 5 DPI, spleen cells of the birds infected with APV markedly decreased proliferative response to concanavalin A (Con A). Con A and lipopolysaccharide stimulation of spleen cells from virus-exposed turkeys resulted in accumulation of nitric oxide-inducing factors (NOIF) in the culture fluid. NOIF were not detected in culture fluids of Con A-stimulated spleen cells of virus-free turkeys. APV did not compromise the antibody-producing ability of turkeys against several extraneous antigens such as Brucella abortus and tetanus toxoid.  相似文献   
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The intensive agricultural use and consequently the drainage of fen soils have caused modifications in structure and nutrient dynamics. Pedogenetic processes result in the formation of typical soil horizons with distinctive soil properties. These are the basis for soil classification. In the present review, results are compiled. Modifications of abiotic and biotic parameters of fen soils due to drainage and rewetting are presented. Recommendations on the further use of fen soils are submitted.  相似文献   
46.
Traditional models of soil organic matter decomposition predict that soil carbon pools with high chemical stability and large physical structure are more resistant against degradation than chemically labile and fine-grained material. We investigated whether soil fauna, by its direct and indirect effects on carbon turnover, would reinforce or counteract this general trend.The effects of four major faunal groups on carbon pools of differing recalcitrance were studied in an extensive microcosm experiment. Ninty-six microcosms were inoculated with nematodes, enchytraeids, collembola, and lumbricids in three densities, including combinations of groups. Bare agricultural soil and soil covered with maize litter were used as substrates. The microcosms were kept under constant conditions at 12 °C and 50% water holding capacity for 60 days. At the end of the experiment, soil particles were separated into size classes (<63 μm, 63-250 μm, >250 μm) and carbon pools were separated into solubility fractions (K2SO4-soluble, pyrophosphate-soluble, insoluble), by means of ultrasonic dispersion and subsequent stepwise solubilisation.Both in bare soil and in soil with litter, the carbon pools with the highest chemical stability (insoluble) and the larger particle sizes (>63 μm) were degraded more intensively than all other pools in the presence of lumbricids. The pools of intermediate chemical stability (pyrophosphate-soluble) underwent simultaneous degradation and neoformation brought about by different animal groups. The chemically most labile pool (K2SO4-soluble) remained largely unaffected by the fauna. Fixation of carbon in microbial biomass was increased by nematodes in bare soil and by enchytraeids in soil with litter. The results illustrate in detail how, under the influence of soil fauna, soil carbon pools are decomposed in a cascade-like process where carbon is transferred from the stable to the more labile pools, while simultaneously a proportion is fixed in microbial biomass and another part is lost as CO2. Thereby, the relationship between a substrate's persistence and its chemical stability and physical size is substantially modified. We summarize the mechanisms that most likely are responsible for the different effects of the investigated faunal groups.  相似文献   
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Anthocyanins from blood orange [Citrus sinensis (L.) Osbeck] juices were isolated and purified by means of high-speed countercurrent chromatography and preparative high-performance liquid chromatography. Structures of the pigments were then elucidated by electrospray ionization multiple mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The major anthocyanins of the juice were characterized as cyanidin 3-glucoside and cyanidin 3-(6"-malonylglucoside). Furthermore, six minor anthocyanins were detected and identified as cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-sophoroside, delphinidin 3-(6"-malonylglucoside), peonidin 3-(6"-malonylglucoside), and cyanidin 3-(6"-dioxalylglucoside). The occurrence of the latter compound in blood oranges is reported here for the first time, together with full NMR spectroscopic data. Further investigations revealed the presence of four anthocyanin-derived pigments, which are formed through a direct reaction between anthocyanins and hydroxycinnamic acids during prolonged storage of the juice. These novel pyranoanthocyanins were identified as the 4-vinylphenol, 4-vinylcatechol, 4-vinylguaiacol, and 4-vinylsyringol adducts of cyanidin 3-glucoside through comparison of their mass spectrometric and chromatographic properties with those of synthesized reference compounds.  相似文献   
49.
In 2008 and 2009, two consecutive outbreaks of Q fever in humans were recorded in the district of Freudenstadt, northern Black Forrest, Baden-Württemberg, Germany. In 2008, a total of 41 persons from a single local community fell ill and were found infected with Coxiella burnetii. Although comprehensive diagnostic and epidemiological outbreak investigations were conducted and control measures taken which included vaccination of ruminants at risk in three parts of the affected community, re-occurrence of the disease in 2009 with further 29 confirmed human Q fever cases could not be prevented. While the origin of infection of the first outbreak was probably a flock of 550 sheep moved in the surrounding of the affected villages, the source of infection for the consecutive outbreak in 2009 could not be identified. It seems possible that meadows contaminated with infectious placenta or birth fluids represented the sources of infection.  相似文献   
50.
Objective: To describe the anatomic features of the equine trochanteric bursa and to evaluate 4 techniques for bursa centesis. Study Design: Prospective, randomized design. Animals: Equine cadavers (n=2) and 20 live horses. Methods: The trochanteric bursae of 2 equine cadavers were injected with latex to identify the boundaries of the bursae. Four techniques for centesis of the trochanteric bursa were evaluated by attempting to inject dye into both trochanteric bursae of 20 live horses. Techniques included injection of the bursa with the limb‐bearing weight and injection with the limb nonweight bearing and supported on a block, with or without ultrasonographic guidance of the needle. Ultrasonographic guidance of the needle was performed with or without the use of a guide channel attached to the ultrasound probe. Each of the 4 techniques was used to inject 10 bursae. The region of the bursa was dissected after horses were euthanatized to determine the location of the dye. Results: The trochanteric bursa was most successfully injected with the limb positioned caudally with the foot on a block, even though topographic landmarks for centesis were more difficult to identify when the limb was in this position. The highest incidence of success was achieved when the needle was inserted using ultrasonographic guidance with the foot in a Hickman block. Conclusion: Positioning the limb caudally with the foot nonweight bearing and on a block facilitated centesis of the trochanteric bursa.  相似文献   
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