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排序方式: 共有416条查询结果,搜索用时 265 毫秒
411.
龙眼的遗传学研究   总被引:1,自引:0,他引:1  
总结了近 2 0多年来龙眼遗传学 ,特别是体细胞遗传学和分子生物学方面取得的研究进展 ,并对龙眼遗传学研究的发展方向和应用前景作了分析  相似文献   
412.
Marine invertebrates contain nutritionally important elements that make them suitable to be included in the human diet, and they are considered an outstanding source of secondary metabolites with multiple biotechnological uses. The sea hare Bursatella leachii is an invasive species in Mar Menor that can be managed through the control of its reproduction and/or by massive biomass removal. In this context, this work evaluated the possible use of biomass from B. leachii in the food and cosmetics industries. Biomass was appraised for nutritional properties, and extracts were prepared and evaluated in vitro for antioxidant and anti-inflammatory capacity, cholinesterase and tyrosinase inhibition, and for total contents in different phenolic groups. It had a moderate moisture level, low ash and fat levels, and an adequate protein amount and protein/lipid ratio. The fatty acids (FA) profile was mainly saturated, dominated by palmitic acid. The methanol extract had the highest acetylcholinesterase inhibition. The acetone extract had the strongest capacity to scavenge 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical, reduce iron, inhibit tyrosinase, decrease nitric oxide production in lipopolysaccharide (LPS)-stimulated microglia cells, and the upmost levels of total phenolics, flavonoids, and tannins. Our results suggest multiple biotechnological applications for B. leachii biomass in different economic areas.  相似文献   
413.
One of the current challenges of global fish farming is developing plant‐based proteins as a feasible substitute for fishmeal in the formulation of aquafeeds. Substitution levels of fishmeal with hydrolyzed soybean meal (HSM) in diets for silver catfish (Rhamdia quelen) were evaluated for growth, protein metabolism and antioxidant activity. The experiment was carried out in a recirculation system of 20 tanks of 250 L. A total of 300 silver catfish juveniles were used to compose five treatments and four replicates per treatment. Levels of soybean hydrolysate (0%, 5%, 10%, 15% and 20%) were tested in diets (39% protein and 3,500 Kcal) for 60 days. Silver catfish growth was higher at all inclusion levels of HSM when compared to the control diet. No change was shown for body protein deposition. The production of nitrogenous compounds in the liver and muscle was also unaffected by any of the diets. The diet containing 20% HSM promoted an increase in the amounts of non‐protein thiols in the gills and brain. The HSM substitution levels of up to 20% of fishmeal in the diet increases growth and contributes to silver catfish antioxidant activity.  相似文献   
414.
The marine environment is an underexplored treasure that hosts huge biodiversity of microorganisms. Marine-derived fungi are a rich source of novel metabolites with unique structural features, bioactivities, and biotechnological applications. Marine-associated Cladosporium species have attracted considerable interest because of their ability to produce a wide array of metabolites, including alkaloids, macrolides, diketopiperazines, pyrones, tetralones, sterols, phenolics, terpenes, lactones, and tetramic acid derivatives that possess versatile bioactivities. Moreover, they produce diverse enzymes with biotechnological and industrial relevance. This review gives an overview on the Cladosporium species derived from marine habitats, including their metabolites and bioactivities, as well as the industrial and biotechnological potential of these species. In the current review, 286 compounds have been listed based on the reported data from 1998 until July 2021. Moreover, more than 175 references have been cited.  相似文献   
415.
桂建芳 《水产学报》2023,47(11):119101-119101
鲫是多倍体鲫属复合种的统称,包括拥有100条染色体的鲫与人工驯养的金鱼以及拥有150多条和200多条染色体的银鲫。它们不仅是重要养殖鱼类,而且是稀有的具有不同倍性的脊椎动物,为研究脊椎动物单性生殖及多倍化机制提供了潜在机会。本文综述了银鲫在遗传进化上的特殊性以及近五年来揭示的基因组演化方面的创新见解,尤其是在精准育种上取得的相关重要突破,结合我们育种实践积累的经验,展望水产育种和水产种业的未来发展。  相似文献   
416.
现代生物技术对血吸虫病诊断的推动作用   总被引:2,自引:0,他引:2  
现代生物技术是新技术革命的重要标志之一,为血吸虫师诊断提供了新技术,新方法和新思路,使血吸虫病诊断的敏感性和特异性显著提高,酶免疫转移印渍技术使血吸虫病诊断上升到分子水平。  相似文献   
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