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41.
In aquaculture industries, there is an urgent need to develop microbial control strategies, to control disease outbreaks. In recent years, probiotics are considered as a valid alternative for the use of antibiotics in aquaculture to prevent high mortality and promote growth. In the present study, seven strains of bacteria such as Bacillus licheniformis (DAB1), Bacillus pumilus (DAB2), Bacillus sp. (DAB3), Pseudomonas aeruginosa (DAP1), Pseudomonas sp. (DAP2), Pseudomonas aeruginosa (DAP3), Pseudomonas aeruginosa (DAP4), and three pathogenic Vibrio parahaemolyticus (DAV1, DAV2, DAV3) were isolated from healthy and diseased Fenneropenaeus indicus collected from the east coast of Tamilnadu, India. The strains were identified by biochemical analysis and 16S rRNA sequence methods. Among the seven probiotic strains tested, the cell-free extract from DAB1 and DAP1 exhibited higher inhibitory activity of V. parahaemolyticus than other isolates under in vitro conditions. The LC50 of DAV1, DAV2, and DAV3 was found to be ~103 CFU mL?1. Pathogenicity of three V. parahaemolyticus DAV1, DAV2, and DAV3 showed significant mortalities (40 %) in Artemia nauplii at inoculation densities of 103 CFU mL?1 when compared to the controls (unchallenged nauplii). A significant reduction in mortality (P < 0.001) was found by addition of 106 CFU mL?1 of DAB1 and DAP1 strains in nauplii against the pathogens. In conclusion, the present study result reveals that DAB1 and DAP1 have potential applications for controlling pathogenic V. parahaemolyticus in Artemia culture systems and aquaculture practices.  相似文献   
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OBJECTIVES: To determine the effects of pentoxifylline (PTX) administration on lung function and results of cytologic examination of bronchoalveolar lavage fluid in horses affected by recurrent airway obstruction (RAO). ANIMALS: 10 RAO-affected horses. PROCEDURES: 6 horses were orally administered PTX (16 g) mixed with corn syrup, and 4 horses were administered corn syrup alone, twice daily for 14 days. Pulmonary function was evaluated before administration (day 0) and on days 8 and 15. Bronchoalveolar lavage (BAL) was performed on days 0 and 15. Reversibility of airway obstruction was assessed by measuring pulmonary function before and after administration of atropine (0.02 mg/kg, IV). Serum concentration of PTX was measured in 4 horses 30 minutes and 2 and 4 hours after administration of PTX on days 1, 2, 3, 7 and 14. RESULTS: Administration of PTX to BAO-affected horses resulted in a decrease in elastance value on day 8 and on elastance and resistance (RL) values on days 8 and 15. Results for cytologic examination of BAL fluid obtained on day 15 did not differ significantly, compared with values for day 0. Values of RL decreased in all horses following administration of atropine. When mixed in corn syrup and administered orally, PTX was poorly absorbed in horses, and there was noticeable variation in serum PTX concentrations over time and among horses. CONCLUSIONS AND CLINICAL RELEVANCE: Based on these results, it can be concluded that administration of PTX at high doses improved respiratory function of RAO-affected horses maintained in an unfavorable environment.  相似文献   
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Development of antimicrobial resistance is an inevitable consequence of exposure of microorganisms to antimicrobial agents. Although emergence of resistance cannot be prevented, it can be retarded by minimizing use of antimicrobial agents and avoiding selection of relatively resistant pathogenic and nonpathogenic strains caused by exposure to tissue concentrations that confer a competitive advantage. Most attention in veterinary medicine has focused on the emergence of resistance in food-borne pathogens, with relatively little attention being devoted to small companion animals, despite the frequent use of antimicrobial agents in these animals, evidence that resistance is emerging, and potential for transfer of resistance between companion animals and people. To retard further emergence of resistance in small companion animals, it is imperative that surveillance programs be instituted to monitor development of resistance.  相似文献   
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We examined the criteria for sleeping place selection in a social band of Rhinopithecus bieti (black‐and‐white snub‐nosed or golden monkeys) living in the mountainous Samage Forest, Baima Snow Mountain Nature Reserve, Yunnan, China. We performed principal component analysis and found that slope aspect, tree height and trunk diameter were likely key variables influencing selection of sleeping places. Sleeping sites were preferentially located in mixed deciduous/conifer forest. The monkeys slept exclusively in evergreen trees, of which 82% were conifers (mostly Picea likiangensis and Tsuga dumosa) and 18% evergreen oaks (Cyclobalanopsis oxyodon and Quercus spp.). Sleeping trees were tall (mean 30.5 m), had high boles (mean 18.4 m), large diameters (mean 62.6 cm) and large crown areas (mean 57.9 m2). A comparative analysis of phytological and architectural features between trees in “sleeping site plots” (n= 18) and trees in “non‐sleeping‐site plots” (n= 66) revealed that diameter, crown surface area and tree height were significantly (P < 0.01) larger in the former compared with the latter. All investigated roosting sites were situated on steep mountain slopes. Valleys and mountain ridges were avoided. We also detected re‐use of roosting sites on several occasions, but not on consecutive nights. It is most likely that a mix of factors (stability of trees, access to food, unit cohesion, monitoring potential) explains the pattern of sleeping site preference, but predation at night seems to be only slightly important. Climate appears to have a profound influence on patterns of sleeping site selection in the monkeys' harsh temperate habitat. This is demonstrated by the monkeys' preference for mixed forest at medium elevations over montane fir forest at high elevations and slopes instead of ridges, with reduced exposure to wind and precipitation inherent in the former. We also emphasize the possibly substantial role that non‐environmental factors (the nature of social organization and socio‐behavioral strategies) play in determining sleeping site use in R. bieti and other primates.  相似文献   
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As part of a wider study characterizing tree-to-tree variation in fruit traits as a pre-requisite for cultivar development, fruits were collected from each of 63 marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and from 55 trees from the North Central Region of Namibia. The nuts were removed from the fruit flesh, and the kernels extracted, counted and weighed individually to determine the patterns of dry matter partitioning among the nut components (shell and kernel) of different trees. Mean nut, shell and kernel mass were not significantly different between the two countries. Between sites in South Africa there were highly significant differences in mean nut mass, shell mass, kernel mass and kernel number. In Namibia, there were highly significant differences between geographic areas in mean shell mass, kernel mass and kernel number, but not in nut mass. These differences had considerable impacts on shell:kernel ratios (8.0 - 15.4). In South Africa, mean kernel mass was significantly greater in fruits from farmers fields (0.42 g) than from communal land (0.30 g) or natural woodland (0.32 g). Within all sites, in both South Africa and Namibia, there was highly significant and continuous variation between individual trees in nut mass (South Africa = 2.3 - 7.1 g; Namibia = 2.7 - 6.4 g) and kernel mass (South Africa = 0.09 - 0.55 g; Namibia = 0.01 - 0.92 g). The small and valuable kernels constitute a small part of the nut (Namibia = 6.1- 11.1%; South Africa = 7.6 - 10.7%). There can be 4 kernels per nut, but even within the fruits of the same tree, kernel number can vary between 0-4, suggesting variation in pollination success, in addition to genetic variation. The nuts and kernels of the Namibian trees were compared with the fruits from one superior tree (Namibian Wonder: nuts = 10.9 g; kernels = 1.1 g). Oil content (%) and oil yield (g/fruit) also differed significantly between trees (44.7 - 72.3% and 8.0 - 53.0 g/fruit). The percentage frequency distribution of kernel mass was skewed from trees in farmers fields in South Africa and in some sites in Namibia, suggesting a level of anthropogenic selection. It is concluded that there is great potential for the development of cultivars for kernel traits, but there is also a need to determine how to increase the proportion of nuts with four kernels, perhaps through improved pollination success.  相似文献   
49.
Concern has been expressed over the welfare of horses transported from the USA for slaughter in Canada. United States Department of Agriculture owner/shipper certificates for the year 2009 were analyzed to provide quantitative information on the patterns and durations of these journeys. In 2009, horses from 16 states in the northern USA were transported to 6 equine slaughter plants in Canada. Thirty-two percent of loads were from auction centers, 33% from feedlots, and 35% from horse collection centers. The median duration of the journey was 19 h. Thirty-six percent of horses were transported for < 6 h, 11% for 6 to 18 h, 13% for 18 to 24 h, 25% for 24 to 36 h, 9% for 36 to 48 h, and apparently 6% > 48 h. Some journeys exceeded those specified in regulations and, based on other research, would put these horses at risk of negative welfare outcomes, such as dehydration, injury, and fatigue.  相似文献   
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Plantain grown after forest slash-and-burn raises concerns due to the release of CO2 and the destruction of biodiversity. Plantain yields are presented after forest biomass was burned or retained in combination with sucker sanitation versus traditional planting. Biomass burning did not affect plant crop and total yield. Soil chemical properties were weakly positively affected by burning. Sucker sanitation increased total yield at one site from 6.2 to 9.7 Mg ha?1 (p = 0.015), without effects on root health. In the second site, sucker sanitation had no effect on fresh bunch yield (mean 8.59 Mg ha?1), yet significantly improved root health parameters. Thus, at the first site, sucker sanitation elicited a positive response via a mechanism different from nematode control. At the second site, by contrast, nematode control was not the most important factor in yield formation. These data do not support the notion that retaining biomass increases plantain production. Other factors related to labor requirements and later weed infestation are probably more important in farmers' decision making on biomass management.  相似文献   
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