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随着人们生活水平的提升,鲫鱼成为人们餐桌上不可或缺的重要美食,市场对鲫鱼的需求量较大,所以近年来池塘驯化养殖鲫鱼得以快速的发展。文中对良种鲫鱼的品种进行了介绍,同时对养殖进行了试验对比,并进一步对池塘驯化养殖技术进行了具体的阐述。 相似文献
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为了解居民家庭对过期药品处理的现状,设计了调查问卷分别针对城乡社区进行调查,在对调查数据进行分析的基础上得出调查结论,并提出相应对策建议。 相似文献
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对选修北京师范大学2010年夏季学期"图书馆利用与信息检索"课程的大二学生进行了调查,在调查反馈的基础上对调查结果进行了分析,并对文献检索课程的改进进行了思考。 相似文献
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北京市城市居民休闲状况分析 总被引：2，自引：0，他引：2
2001年下半年，中国人民大学生活时间分配课题组，进行了北京市居民生活时间分配调查。调查方式为人户调查，调查的有效样本量为703人。本文以这次调查的数据为基础，对北京市城市居民休闲生活进行分析。 相似文献
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The acidification of water leads to disturbances in the water and ion metabolism of fish, including the acid-base balance. Many fish probably possess physiological mechanisms to eliminate these disturbances completely or in part. However successful they may be in the short term, such adaptation mechanisms nevertheless require additional energy, thus causing growth and reproduction to be retarded. Taking into account the high sensitivity of fish eggs and larvae to acidification, these phenomena are probably a major contributory factor to the decline of fish stocks in acidified water. 相似文献
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鱼类干扰素系统基因的克隆鉴定及其特征分析 总被引：2，自引：0，他引：2
干扰素 (IFN)系统是脊椎动物抵抗病毒入侵的第一道防御系统 .除了哺乳类 ,有关低等脊椎动物的IFN系统基因知之甚少 .在鱼类 ,近 40年来能证明IFN系统存在的证据主要有两个 :一是检测经病毒诱导后的多种鱼类机体和细胞 ,证明能产生类似哺乳类IFN的抗病毒活性物质 ;二是近年来 ,已经证明在少数几种鱼类中存在与哺乳类IFN系统基因Mx同源的基因 .以前的研究结果表明 ,紫外线灭活的草鱼出血病病毒 (GCHV)能够诱导鲤科鱼类培养细胞 ,如鲫鱼囊胚细胞 (CAB)产生类IFN活性物质 ,并建立宿主细胞的抗病毒状态 .为了揭示鱼类培养细胞抗病毒免疫的分子机制 ,首先建立了一个研究鱼类抗病毒免疫相关基因的细胞模型系统 ,通过用灭活GCHV诱导CABIFN并进行理化、生物学特性鉴定的基础上 ,成功建立了一个囊括鱼类细胞抗病毒基因在内的差减cDNA文库 .其次 ,筛选文库揭示了一批与哺乳类IFN系统基因同源以及找不到同源性的EST ,表达分析证实它们也是IFN刺激基因 .再次 ,根据哺乳类IFN系统研究的最新进展 ,从该细胞模型系统中克隆、鉴定了 1 9个IFN系统基因的全长cDNA序列 ,包括鲫鱼IFN基因 ,IFN信号传导通路基因STAT1 ,IFN诱导表达调控基因IRF7,IFN行使抗病毒作用的效应基因Mx1、Mx2、PKR、Viperin、IFI5 6,以及一些功能未知的 相似文献
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Angela Godwin H. Ramachandra Prabhu 《Indian journal of clinical biochemistry : IJCB》2006,21(1):202-204
Fish and fish oils are the richest sources of ω-3 fatty acids. However, they are susceptible to lipid peroxidation due to
their high degree of unsaturation. In the present study, the level of thiobarbituric acid reactive material in various fish
oils available in the market with and without added Vitamin E was determined. The peroxide levels in fish oil heated to food
frying temperature of 180°C and the effect of addition of vitamin E has also been studied. The results indicate that the peroxide
levels in almost all the products available in the market were abnormally high irrespective of their Vitamin E content. This
might be due to the inefficient methods used for processing and storage of fish oils. Addition of vitamin E was found to have
a significant effect in lowering the rate of peroxidation of fish oil during thermal stress, showing that association of antioxidants
with ω-3 fatty acids lowers the rate of lipid peroxidation. 相似文献
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M. Nandini M. Abdul Rahiman S. Narasimha Rao 《Indian journal of clinical biochemistry : IJCB》2000,15(2):161-166
The effect of dietary supplementation with Oil sardine (Sardinella longiceps) fish at 2/3 fat replacement, on serum lipids in the cholesterol-stressed copper loaded rats was studied. Hypercholesterolemic
state observed during copper toxicity was not alleviated by sardines. Copper loading significantly decreased the triglyceride
levels and the activity of β-hydroxy β-methyl glutaryl (HMG) CoA reductase. Fish supplementation was further effective in
reducing the triglyceride levels in copper loaded rats. Significant increase in the serum phospholipid was observed in the
fish supplemented rats during copper overload. The finding suggests that hypolipidemic potential of fish is certainly altered
to some extent in copper toxicity since, it is well known that copper enhances the formation of free radicals. Thus it may
be concluded that sardine fish is not effective in reducing the cholesterol levels during copper toxicity. 相似文献
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多仿生机器鱼群体及单体控制体系结构的研究 总被引：1，自引：0，他引：1
多仿生机器鱼群体协作与控制的研究,是针对未来仿生机器鱼在水下作业、海洋考察、军事侦察等方面的实际应用而开展的相关理论和关键技术的研究。控制体系结构是其中很重要的一个研究内容,也是今后进一步开展研究工作的基础。考虑到机器鱼自主性和协作性的要求,本文给出了多仿生机器鱼群体和单体控制体系结构,并重点讨论了单体控制体系结构。该体系结构是混合分层的,具有较好的开放性,便于功能的扩展 相似文献
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Objective:PCDD/Fs level in 22 fish samples was investigated in Pearl river Delta area in order that the PCDD/Fs pollution level in common fish can be evaluated. Methods: Dibenzo-p-Dioxins and Dibenzo-Furans was extracted from the sample by Soxhlet extraction, concentrated then purified by column chromatography, carbon column enrichment,. Confirmation and quantitative analysis at ppt(pg/g) level of PCDD/Fs was performed by HRGC/HRMS using multiple ion detection mode(MID). Certified reference material using Proficiency test sample fish muscle test material 0613 that was obtained from Central Science Laboratory(CSL) in Britain. Results: The average of concentration in wet weight is 1.261 ng/kg,, the average total WHO-TEQ for 22 samples is 0.246ng/kg wet weight. Generally, OCDD, 2,3,7,8-TCDF,1,2,3,4,6,7,8-HpCDD was the main contributors to the total 17 PCDD/Fs detected, average account for 21%,16%,14%, respectively. While 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD were main contributors to the total WHO-TEQ, account for 40%,27%,13% respectively. The total TEQ for 22 fishes ranged from 0.03ng/kg wet weight to 0.878 ng/kg wet weight. Conclusions: PCDD/Fs level was largely different from sample to sample depending on the sample kinds. The level in the Pearl river Delta area fish samples is not distinct comparing with other countries, but some kind fish level should be paid more attention on it since its higher level. The relationship between source of PCDD/Fs and PCDD/Fs level in fish will be studied deeply in the future. 相似文献
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基于2009年11-12月和2010年3-4月对增江流域13个样点进行的鱼类资源调查,并结合20世纪80年代的历史资料,分析了增江鱼类群落特征现状及历史变化.结果表明:本次调查共采集鱼类72种,隶属于7目18科60属.与20世纪80年代调查结果相比,物种数相差较小,但两次调查均采集到的鱼类只有43种,种类相似性指数仅为0.44.调查发现新记录种29种,其中多为小型鱼类.但历史记载的26种鱼类在此次调查中未发现.增江鱼类生态类型目前以习缓流或静水、中层栖息、杂食性、定居性鱼类为主.较历史相比,洄游性鱼类种类所占比例变化最大,从19.12％降至11.11％.亲流型种类物种组成相似性变化最大,物种相似性指数仅为0.25.目前增江支流渔获对象在多度和数量上均占优势的为宽鳍鱲(Zacco platypus)、南方波鱼(Rasbora cephalotaenia steineri)、马口鱼(Opsariichthys bidens),其中宽鳍鱲为绝对优势种.干流地区为尼罗非鲫(Oreochromis niloticus)、鲮(Cirrhinus molitorella)、三角鲂(Magalobrame Tarminalis)等,其中,尼罗非鲫是绝对优势种.曾在80年代占据增江渔业主体的黄尾鲴(Xenocypris david)、赤眼鳟(Squaliobarbus curriculus)等物种渔获量已大幅下降.调查发现入侵鱼类4种,其中露斯塔野鲮(Labeo rohita)、下口鲶(Hypostomus plecostomus)和尼罗非鲫在20世纪80年代调查中未发现,为新记录种.调查结果表明增江地区鱼类组成发生了较大变化,而这些变化可能是由该地区大规模挖沙、水坝建设、不合理捕捞、外来鱼类入侵、水域污染等因素导致. 相似文献