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91.
Four levels of fish oil and macroporous cation strong acid-resin volume ratios, 1:1, 2:1, 3:1, and 4:1, were used to determine the optimum ratio in terms of the quality of refined oil or fraction-1. Fraction-1 (freely flown oil or refined oil) and fraction-2 (oil retained in the column) were analyzed regarding their quality based on free fatty acid, refractive index, colour, fatty acid profile and sensory evaluation. The results showed that resin refining process significantly improved the fish oilÆs chemical, physical and sensory quality characteristics. The omega-3 fatty acid content in the refined oil fraction was maintained and the level in fraction-2 was significantly higher than the level in fraction-1. Sensory evaluation indicated that the fraction-1 was significantly better than fraction-2. The fish oil and resin volume ratio of 1:1 was found to be the best due to improvement in sensory and chemical characteristics.  相似文献   
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93.
我国海产贝类体中的麻痹性毒素及其来源   总被引:8,自引:0,他引:8  
林燕棠 《水产学报》2001,25(5):479-481
在目前已知的海洋藻类毒素中麻痹性毒素(Paralytic Shellfish Poison,PSP)是毒害事件发上频率最高、对人类影响最为严重的一类毒素。文献记载最早发生该类中毒事件的地区,主要是在欧洲和北美的一些海域[1、2]。据不完全统计,在我国因食用染毒贝类引起的中毒事件有几十起,主要发生在东海和南海海域。因此,贝类麻痹性毒素的含量状况和上市贝类的质量是消费者极为关注的问题,同时也是有关海域渔业可持续发展的保证条件之一。为维护和发展贝类养殖业,保证海产品的质量和促进海产品的出口贸易等,深入…  相似文献   
94.
马苏 《中国兽药杂志》2012,46(2):50-52,56
通过阐述动物源细菌耐药性的产生及演变趋势,分析抗生素在兽医领域中的应用情况,探讨动物细菌传染性疾病的防治策略,旨在了解细菌耐药性对动物细菌传染性疾病治疗的影响,为兽用药品特别是兽用细菌疫苗的发展提供参考,促进动物卫生安全和公共卫生安全。  相似文献   
95.
An analysis of records of plant pathogens first identified in Great Britain from 1970 to 2004 (inclusive) was undertaken to determine the numbers of new species that have become established over time. Results show that the numbers of newly recorded pathogens have not varied significantly. Of the 234 pathogens recorded for the first time between 1970 and 2004, 157 were fungi, 27 were oomycetes, 26 were viruses, 23 were bacteria, and one was a phytoplasma. Approximately 53% of pathogens were found on ornamental crops, 16% on horticultural crops, 15% on wild native species, 12% on agricultural crops, 2% on pasture plants and 2% on exotic forestry tree species. Where the origin of introductions was known or strongly suspected, 47% came from the Netherlands. About 38% of newly recorded pathogens with information on the location of first record were discovered in the South East region of England. Plant Pathologists regarded 19% of all new pathogens as important because of actual or potential economic/environmental losses. The results indicate that the numbers of new or important pathogens establishing in recent years are not increasing and that most new findings are associated with ornamental plants.  相似文献   
96.
An unknown Phytophthora species was discovered in the central Peruvian Andes on blighted foliage of the native South American plant species Urera lacineata. Urera is a genus of native flowering shrubs in the nettle family Urticaceae. This new taxon Phytophthora urerae sp. nov. is herewith formally described based on extensive morphological analysis, phylogenetic analysis of nuclear and mitochondrial loci, and AFLP analysis. Phytophthora urerae sp. nov. is a close relative of the Irish famine pathogen, Phytophthora infestans, and only the third clade 1c taxon described from South America to date. In contrast to the clade 1c taxon Phytophthora andina, first described in South America as a hybrid, P. urerae does not appear to be a hybrid based on cloning and sequencing nuclear loci. Findings of new species in South America may provide novel insights into the origin and evolutionary history of clade 1c Phytophthora species.  相似文献   
97.
内蒙古牙克石市喇嘛山有海西期至燕山期白岗质花岗岩岩组和花岗斑岩岩组出露。受新华夏构造体系波及,塑性地层发生褶皱,刚性岩层断裂,形成区内大小28座突兀挺拔、陡峭嶙峋的花岗岩奇峰;又由于该区气候湿润,岩石风化、溶蚀较快,周围岩石脱落,导致各种类型的花岗岩峰石球化,形成大量石蛋、石柱、象形石、石槽、岩臼、石穴等微地貌。文中简述了喇嘛山花岗岩景观的类型、特征,对其成因进行了分析。  相似文献   
98.
 Eight hundred twenty four nit mutants were induced from 73 strains of Fusarium oxysporum f. sp. vanillae, and classified into four phenotypes by their abilities to utilize different nitrogen sources. Among these mutants, 64.9% were characterized as nit 1, 24.3% as nit 3, 9.8% as nit M, 1.0% as nit X. Based on complementary pairing tests of different nit mutants on the medium MM, 44 isolates belonged to 8 different VCGs, 29 isolates were classified into single and different VCGs. These results indicated that there was significant VCG diversity in Fusarium oxysporum f. sp. vanillae population. VCGs might be correlated with geographic origin of strains, but no close correlation was found between VCGs and pathogenicity.  相似文献   
99.
利用QuEChERS技术结合超高效液相色谱-串联质谱的方法检测5种动物源食品(鸡肉、鸡蛋、猪肝、牛奶、猪肉)中氟虫腈及其3个代谢物残留量。样品用乙腈提取,经低温处理,多壁碳纳米管(MWCNTs)、弗罗里硅土(Florisil)和C18分散固相萃取(d-SPE)净化,外标法定量。在不同浓度的加标水平下,氟虫腈及其代谢物在5种动物源食品中的平均回收率为72.1%~113.8%,相对标准偏差RSD为1.9%~17.6%,检出限LOD在0.73~1.94μg/kg范围内,定量限LOQ在5~10μg/kg范围内。该方法具有简单、灵敏、准确等优点,适用于动物源食品中氟虫腈及其代谢物的快速筛查和定量检测。  相似文献   
100.
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