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1.
Kaolin treatment to reduce pomegranate sunburn   总被引:1,自引:0,他引:1  
The aim of this study was to reduce pomegranate losses due to sunburn in south-western Spain. Summer temperatures may rise above 45 °C, resulting in sunburn damage to the fruits, which may inflict losses of up to 40% of the total yield. Data were obtained in two consecutive years. Surround® WP, a product comprising processed, refined kaolin, was sprayed over the whole canopy and fruits four times at 2–3-week intervals from mid-June to early August, the first application at 5% and the other three at 2.5%. The resulting white coating significantly reduced fruit and leaf surface temperatures relative to the control by averages of 4.9 and 2.5 °C, respectively. Sunburn damage of fruits was reduced from 21.9% in untreated control to 9.4% in the Surround WP-treated fruits.  相似文献   
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Quantitative analysis of culture using millions of digitized books   总被引:1,自引:0,他引:1  
We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of 'culturomics,' focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. Culturomics extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities.  相似文献   
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It has been assumed that marine habitats and resources, especially, are almost unlimited, and that if one habitat became degraded or a particular fisheries resource depleted, there always would be another to replace it. Therefore, natural resource management principals are beginning to include human motivation and responses as part of the marine and coastal systems that are being studied and managed. Managers of marine resources face the challenge of balancing conservation and development objectives in the context of the inherent uncertainty of natural systems and the political and social pressures of human systems. Natural resource managers, scientists and the general public seem to share a vision for the future as a world in which societal and economic decisions will be strongly coupled with an increasingly comprehensive understanding of the environment. This in turn will lead to both socio-economic health and ecosystem health. A paradigm shift is being seen in the evolution of the role of scientists in society from simply observers of the natural world with tenuous linkages to resource managers and the public, to partners in modern society's quest for answers to pressing questions related to sustainable use and conservation of natural resources. A US Agency for International Development supported, joint effort between the US National Oceanic and Atmospheric Administration, the Government of Israel and the Hashemite Kingdom of Jordan to conduct a comprehensive research and monitoring program directed at the new Binational Red Sea Marine Pearce Park will be a pioneering effort to employ and test this new paradigm.  相似文献   
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Cells remove proteins by two processes: degradation and dilution due to cell growth. The balance between these basic processes is poorly understood. We addressed this by developing an accurate and noninvasive method for measuring protein half-lives, called "bleach-chase," that is applicable to fluorescently tagged proteins. Assaying 100 proteins in living human cancer cells showed half-lives that ranged between 45 minutes and 22.5 hours. A variety of stresses that stop cell division showed the same general effect: Long-lived proteins became longer-lived, whereas short-lived proteins remained largely unaffected. This effect is due to the relative strengths of degradation and dilution and suggests a mechanism for differential killing of rapidly growing cells by growth-arresting drugs. This approach opens a way to understand proteome half-life dynamics in living cells.  相似文献   
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Tropical Animal Health and Production - The polymorphisms of the PRNP gene influence the susceptibility to scrapie in goats. In this study, caprine PRNP gene was analysed in a total of 249...  相似文献   
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‘Sunred’ nectarine trees were grown in a meadow orchard system of 19,000 plants per hectare. By cutting back all tree top down to the lowest 5 cm of one-year-old wood, immediately after cropping, renewed growth was initiated, flowers differentiated, and the original size of the well-feathered tree was recovered at the end of the growing-season. Thus annual cropping was obtained with a rhythmic change of tree size between two constant levels. Three such consecutive cycles were completed with no sign of tree decline. Bud opening was delayed by about 2 weeks. Fruit bearing was very early, with fruit size smaller and ripening-time later than fruit from conventional mature trees. Yields were about 37, 62 and 94 % of the yield of a conventional adult orchard in the 1st, 2nd and 3rd seasons respectively.  相似文献   
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Mastitis, inflammation of the mammary tissue, is a common disease in dairy animals and mammary pathogenic Escherichia coli (MPEC) is a leading cause of the disease. Lipopolysaccharide (LPS) is an important virulence factor of MPEC and inoculation of the mammary glands with bacterial LPS is sufficient to induce an inflammatory response. We previously showed using adoptive transfer of normal macrophages into the mammary gland of TLR4-deficient C3H/HeJ mice that LPS/TLR4 signaling on mammary alveolar macrophages is sufficient to elicit neutrophil recruitment into the alveolar space. Here we show that TLR4-normal C3H/HeN mice, depleted of alveolar macrophages, were completely refractory to LPS intramammary challenge. These results indicate that alveolar macrophages are both sufficient and essential for neutrophil recruitment elicited by LPS/TLR4 signaling in the mammary gland. Using TNFα gene-knockout mice and adoptive transfer of wild-type macrophages, we show here that TNFα produced by mammary alveolar macrophages in response to LPS/TLR4 signaling is an essential mediator eliciting blood neutrophil recruitment into the milk spaces. Furthermore, using the IL8 receptor or IL1 receptor gene-knockout mice we observed abrogated recruitment of neutrophils into the mammary gland and their entrapment on the basal side of the alveolar epithelium in response to intramammary LPS challenge. Adoptive transfer of wild-type neutrophils to IL1 receptor knockout mice, just before LPS challenge, restored normal neutrophil recruitment into the milk spaces. We conclude that neutrophil recruitment to the milk spaces is: (i) mediated through TNFα, which is produced by alveolar macrophages in response to LPS/TLR4 signaling and (ii) is dependent on IL8 and IL1β signaling and regulated by iNOS-derived NO.  相似文献   
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