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The composition and antioxidant activity of Italian poplar propolis obtained using three harvesting methods and extracted with different solvents were evaluated. Waxes, balsams, and resins contents were determined. Flavones and flavonols, flavanones and dihydroflavonols, and total phenolics were also analyzed. To characterize the phenolic composition, the presence of 15 compounds was verified through HPLC-MS/MS. The antioxidant activity was evaluated through 1,1-diphenyl-2-picrylhydrazyl radical and reducing power assays. The ability of propolis to inhibit lipid oxidation was monitored by analyzing hydroperoxide and TBARS formation in lipids incorporated into an oil-in-water (O/W) emulsion. Acetone shows the highest extraction capacity. Wedge propolis has the highest concentration of active phenolic compounds (TP = 359.1 ± 16.3 GAEs/g; TFF = 5.83 ± 0.42%; TFD = 7.34 ± 1.8%) and seems to be the most promising for obtaining high-value propolis more suitable to prepare high-quality dietary supplements (TBARS = 0.012 ± 0.009 mmol std/g; RP = 0.77 ± 0.07 TEs/g).  相似文献   
73.
Invasive alien species cost forestry billions of euros every year and their early detection is becoming of utmost importance. The aim of this study is to improve some of the techniques available for trapping alien wood boring beetles (Scolytinae, Cerambycidae, and Buprestidae) arriving at high-risk sites, such as ports. During 2009–2011, trapping carried out in four Italian seaports tested the comparative efficiency of different luring (single-lure vs. multi-lure traps) and trap designs (cross-vane vs. multi-funnel). In addition, trap captures within the ports were compared with those obtained in surrounding areas. Six out of 49 species trapped in 3 years of investigation were of alien origin: four Scolytinae and two Cerambycidae. The number of species trapped in multi-lure traps was as high as that resulting from the sum of the single-lure traps. The two trap designs performed equally well, but multi-funnel traps were more robust and easier to use in ports. In 2011, the number of species trapped in ports and surrounding areas was similar, although differently distributed. On a total of 26 species trapped in this experiment, nine were exclusive to ports, of which three aliens, eight were exclusive to surrounding areas, of which one alien, and nine were common to both habitats, of which one alien. In conclusion, we suggest the use of multi-funnel traps baited with different lures for monitoring alien wood boring beetles in ports. Using traps outside the port is also recommended to validate the surveillance program.  相似文献   
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The aim of this study was to evaluate if the exposure to Avian metapneumovirus (aMPV) and/or to Turkey hemorrhagic enteritis virus (THEV) was significant for the induction of episodes of colibacillosis in aMPV and THEV vaccinated turkeys. Colibacillosis-associated mortality was recorded and longitudinal virological studies performed in three consecutive turkey flocks reared in the same farm. aMPV and THEV diagnostic swabs and blood samples were made once a week up to 14 weeks of age. Swabs were processed by molecular techniques for viruses detection and antibody titres were evaluated. Field subtype B aMPVs were detected in all flocks at different ages of life always associated with respiratory signs and increase of colibacillosis-associated mortality. THEV has been consistently detected in all flocks since the 9th week of age. Vaccination with a single dose of the THEV commercial inactivated vaccine available in Italy seems does not protect the birds from the infection. Sequence comparison of the hexon protein of one of the THEV strains detected, and strains isolated worldwide, revealed high similarity between them. These results are consistent with the notion that the hexon protein, being the major antigenic component of the virus, is highly conserved between the strains. Results showed that field aMPV infection is directly correlated to colibacillosis-associated mortality. Less clear appears the role of THEV because the endemicity of aMPV makes difficult to evaluate its role in predisposing colibacillosis in absence of aMPV. It would be interesting to further investigate this issue through experimental trials in secure isolation conditions.  相似文献   
75.
BACKGROUND: Oil Red O, a stain commonly used to demonstrate lipid in frozen tissue, also may be used to stain air-dried cytologic specimens. OBJECTIVE: The purpose of this study was to prospectively evaluate the value of Oil Red O in identifying lipid to aid in the differentiation of liposarcomas from other types of sarcoma. METHODS: Twelve tumor specimens from dogs were evaluated. The tumors were included in the study if initial cytologic evaluation indicated a sarcoma, and if histologic confirmation was available. Oil Red O was applied to all cytologic specimens. RESULTS: Tumor specimens were diagnosed histologically as liposarcoma (3 well-differentiated, 1 pleomorphic), hemangiopericytoma (n = 3), fibrosarcoma (n = 3), malignant fibrous histiocytoma (n = 1), and undifferentiated sarcoma (n = 1). Cytologic specimens from all liposarcomas showed strong positive staining of cytoplasmic vacuoles for lipid. Specimens from other sarcomas stained negative for Oil Red O, with the exception of weak, irregular positive staining in 1 hemangiopericytoma. CONCLUSION: Our results suggest that Oil Red O staining may be an easy, inexpensive, and useful diagnostic tool for the differentiation of liposarcoma from other mesenchymal neoplasms.  相似文献   
76.
Background: Bronchoalveolar lavage (BAL) allows cell recovery from the lower respiratory tract; differential cell counts of BAL fluid gives important information in the assessment of various bronchial and pulmonary diseases. To the best of our knowledge no study has investigated the relation between the number of cells counted and the reproducibility of BAL fluid differential cell counts. Objective: The purpose of this study was to investigate using statistical methods how many cells should be counted in cytocentrifuged BAL fluid preparations in order to obtain a reliable enumeration of each cell type. Methods: BAL fluid samples from dogs with suspected bronchopulmonary disease were obtained during fiberoptic bronchoscopy with a standardized protocol. Differential cell counts were performed on May–Grünwald–Giemsa‐stained cytocentrifuged preparations by 2 independent observers. Reproducibility for the enumeration of each cell type was expressed as the intraclass correlation coefficient. We considered a threshold level of ≥0.90 to be high and a threshold level of ≥0.85 to be adequate. Results: Forty BAL fluid samples were included in the study. For neutrophils, alveolar macrophages, and eosinophils high reproducibility was reached by counting 200 cells; adequate reproducibility was reached for lymphocytes and bronchial epithelial cells by counting 500 cells. Conclusions: A 500‐cell differential count is required for all types of cells to be quantified with adequate reproducibility in canine cytocentrifuged BAL fluid samples.  相似文献   
77.
Botrytis cinerea is one of the pathogens resulting in the heaviest commercial losses in ornamental cut flowers, and the severity of grey mould disease partly depends on the presence of ethylene in the storage environment. The efficacy of a β-cyclodextrin-based nanosponge 1:8 (CD-NS) - 1-methylcyclopropene (1-MCP) complex was evaluated as a novel control agent in protecting carnation (Dianthus caryophyllus L. ‘Idra di Muraglia’) cut flowers against B. cinerea infection. Two concentrations of this non-volatile 1-MCP formulation (CD-NS complex, 0.25 and 0.5 μL L−1, a.i.) were compared with commercial gaseous 1-MCP (0.25 μL L−1, a.i.), and an inoculated control. A non-inoculated control was also used to assess the natural infection level. Eleven days after inoculation, the development of grey mould on carnation was significantly reduced (59.9% of flower surface) in cut stems treated with the CD-NS complex at low dosage, compared to the high dosage of the CD-NS complex (91.5%), the commercial gaseous 1-MCP formulation (76.2%) and the inoculated control (100.0%). Endogenous ethylene production was associated with symptom development. Results showed a reduced ethylene production in 1-MCP treated flowers (0.25 μL L−1, a.i., both suspended and gaseous formulation). The CD-NS complex could therefore be an effective alternative to conventional chemicals to protect ornamental cut flowers.  相似文献   
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The clinical and pathologic findings related to an infiltrative facial lipoma in a 5-month-old female Holstein Friesian calf are reported. The tumor was congenital, increased in size with time, and deformed the left side of the face and cranial bones. The clinical condition of the calf was good; the only detectable abnormalities were poor weight gain and decreased motility of the left upper lip. Clinical and radiologic data indicated the mass was not removable. Muscle and lymph node invasion by tumor tissue were detected histologically. Infiltrative lipoma is a rare variety of lipoma that has been reported in dogs, cats, horses, and humans. Although its cytologic characteristics are those of a benign tumor, in this patient the invasiveness of the neoplasm was associated with poor prognosis.  相似文献   
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