鱼类生长与生物能量学研究新进展

国家“九五”科技攻关项目(96-008-02-03); 中国科学院重大项目(KZ951-A1-102-01;KZ951-B1-104); 国家自然科学基金(39625006;39670573;39970584); 国家重点实验室基金(39823003); 广东海大畜牧水产有限公司的资助

不同溶剂和抽提方法测定脂肪含量的比较

采用不同方法测定了鱼粉、豆饼、鱼油、豆油的脂肪含量。结果表明,不同测定方法测定的值显著不同,测定鱼粉和豆饼时,以氯仿-甲醇为溶剂抽提测得的脂肪含量高。测定鱼油和豆油时,氯仿-甲醇冷抽提测定的值较高。

圆形碘泡虫孢子的分离纯化与裂解

中国科学院重大项目 (KZ951 -B1 -1 1 1 ) ; 中国科学院生命科学与生物技术青年科学家小组项目( 1 9990 51 ) ; 中国科学院知识创新项

用鳞片和耳石鉴定鲫年龄的比较研究

两观测者独立观测了分别采自洪湖的 1 75尾和洞庭湖的 1 6 8尾鲫样本的鳞片和耳石 ,结果显示鳞片适于鉴定年龄组成简单、生长较快的洞庭湖鲫种群的年龄 ,两观测者年轮读数的总吻合率可达 90 5% ,与耳石上年轮读数的吻合率也可高达 91 7% ;但用鳞片鉴定年龄结构复杂、生长缓慢的洪湖鲫种群年龄 ,两观测者总吻合率只有 50 9% ,各龄组吻合率随年龄上升而迅速下降 ,与耳石上年轮读数总吻合率也仅为 56 6 % ,存在比耳石低估高龄个体年龄的问题。用耳石鉴定鲫年龄具有易于识别、精确度高的优点 ,用之

池养条件下中华绒螯蟹的若干生物学特征(英文)

开展中华绒螯蟹 (Eriocheirsinensis)生物学研究 ,对指导养殖具有重要意义。 1 993年 6月 2 0日购于上海市崇明县的仔蟹放养于湖北省保安湖渔场的一个试验塘 (2 3 3 0m2 ) ,每天投喂小杂鱼和螺蚌肉。在试验期间 ,河蟹成活率为 1 8.6 %。协方差分析表明 ,性别对各月体重与壳长、体重与壳宽及壳宽与壳长回归方程的截距和斜率均无显著影响 (p >0 .0 5) ;但是 ,两性数据混合后的不同月份间回归方程的截距却有显著差异 (p <0 .0 1 )。在每次取样时 ,雄蟹与雌

银鲫两个雌核发育克隆间两性生殖子代的遗传多样性分析

本研究在揭示银鲫两性生殖方式的基础上,对尾人工雌核发育克隆F的卵子与一尾天然雌核发育克隆D的精子授精所获得的18尾FD后代及其亲本进行RAPD分析。扩增结果表明,在18尾FD子代中可检测到丰富的DNA多态片段,这些多态片段来自于银鲫两性生殖的重组。FD子代的扩增图谱不仅与母本的扩增图谱不同,而且个体间的扩增图谱也存在着较大的差异。这些差异的DNA片段根据其来源可基本分为四类。与异精刺激雌核发育的子代的情况不同,两性生殖FD子代间平均遗传距离高达0.23±0.123,远远高于异精刺激雌核发育的子代间的平均遗

长江中下游湖泊淡水贝类的分布及物种多样性

本文记录了长江中下游湖泊贝类 110种 ,其中腹足类 10科 56种 ,双壳类 5科 54种 .并对长江中下游主要湖泊贝类的区系、物种多样性进行比较 .

“永固紫”染料和四氯苯醌中多氯代二苯并二噁/呋喃的分析

采用浓硫酸对5种不同来源的四氯苯醌和“永固紫”染料样品进行溶解分散,用甲苯提取和多层色谱柱纯化,利用同位素稀释法及高分辨气相色谱质谱(HRGCHRMS)联用技术,测定了其中的多氯代二苯并二口恶口英呋喃(PCDDF)的质量比。结果表明“永固紫”染料及其原料中PCDDF的质量比异常高,八氯代二苯并二口恶口英呋喃(OCDDF)已达到μgg级甚至100μgg级,七氯代二苯并二口恶口英呋喃(HpCDDF)和六氯代二苯并二口恶口英呋喃(HxCDDF)质量比也达到ngg级。所有样品的毒性当量浓度(TEQ)均已超过10p

鱼类免疫组织和细胞的研究概况

中国科学院“九五”重大B资助项目(KZ951 -B1 -1 1 1 )

鱼类体液免疫因子研究进展

中国科学院“九五“重大B资助项目 (KZ95 1-B1-111)

我国某厂石墨电极废渣中二噁英的指纹特征

研究发现我国氯碱工业中由于采用石墨电极，产生的固体废渣中含有大量二噁英，其总浓度高达 ３７８．８５μｇ／ｋｇ，二噁英各组异构体浓度指纹的特征表现为以四至八氯代的二苯并呋喃（ＰＣＤＦｓ）为主，其中２，３，７，８位氯取代ＰＣＤＦｓ占废渣中总ＰＣＤＦｓ的８０ ％以上，而多氯代二苯并二噁英（ＰＣＤＤｓ）的浓度仅处于０．０１５ μｇ／ｋｇ水平．根据二噁英国际毒性当量因子（Ｉ－ＴＥＦ），计算出该电解废渣的毒性当量（Ｉ－ＴＥＱ）值为 ２１．６５μｇ／ｋｇ，我国电解废渣中二噁英的这种典型的“氯碱指纹”，在该氯碱工业废水排

蚌科钩介幼虫比较形态学研究──Ⅰ.四个种幼虫的形态

本文报道圆顶珠蚌、鱼尾楔蚌、中国尖嵴蚌、卵形尖嵴蚌育儿囊的特点和钩介幼虫的形态。应用光镜和扫描电镜对四种蚌的钩介幼虫形态进行了观察和比较。结果表明，四种蚌的育儿囊均为外鳃类的同生型，钩介幼虫为有钩型，幼虫的大小、形状、壳表面、壳钩、棘刺、幼虫丝、感觉毛等在不同种之间存在着差异。文中对这些特征在分类上的意义进行了讨论。

Transient ventilation dynamics induced by heat sources of unequal strength

We examine theoretically the transient displacement flow and density stratification that develops within a ventilated box after two localized floor-level heat sources of unequal strengths are activated. The heat input is represented by two non-interacting turbulent axisymmetric plumes of constant buoyancy fluxes B1 and B2 > B1. The box connects to an unbounded quiescent external environment of uniform density via openings at the top and base. A theoretical model is developed to predict the time evolution of the dimensionless depths λj and mean buoyancies δj of the 'intermediate' (j = 1) and 'top' (j = 2) layers leading to steady state. The flow behaviour is classified in terms of a stratification parameter S, a dimensionless measure of the relative forcing strengths of the two buoyant layers that drive the flow. We find that dδ1/dτ α 1/λ1 and dδ2/dτ α 1/λ2, where τ is a dimensionless time. When S 1, the intermediate layer is shallow (small λ1), whereas the top layer is relatively deep (large λ2) and, in this limit, δ1 and δ2 evolve on two characteristically different time scales. This produces a time lag and gives rise to a 'thermal overshoot', during which δ1 exceeds its steady value and attains a maximum during the transients; a flow feature we refer to, in the context of a ventilated room, as 'localized overheating'. For a given source strength ratio ψ = B1/B2, we show that thermal overshoots are realized for dimensionless opening areas A < Aoh and are strongly dependent on the time history of the flow. We establish the region of {A, ψ} space where rapid development of δ1 results in δ1 > δ2, giving rise to a bulk overturning of the buoyant layers. Finally, some implications of these results, specifically to the ventilation of a room, are discussed. © Cambridge University Press 2013.

Sox genes in grass carp (Ctenopharyngodon idella) with their implications for genome duplication and evolution

The Sox gene family is found in a broad range of animal taxa and encodes important gene regulatory proteins involved in a variety of developmental processes. We have obtained clones representing the HMG boxes of twelve Sox genes from grass carp (Ctenopharyngodon idella), one of the four major domestic carps in China. The cloned Sox genes belong to group B1, B2 and C. Our analyses show that whereas the human genome contains a single copy of Sox4, Sox11 and Sox14, each of these genes has two co-orthologs in grass carp, and the duplication of Sox4 and Sox11 occurred before the divergence of grass carp and zebrafish, which support the "fish-specific whole-genome duplication" theory. An estimation for the origin of grass carp based on the molecular clock using Sox1, Sox3 and Sox11 genes as markers indicates that grass carp (subfamily Leuciscinae) and zebrafish (subfamily Danioninae) diverged approximately 60 million years ago. The potential uses of Sox genes as markers in revealing the evolutionary history of grass carp are discussed.

Insecticide resistance in Chinese populations of the Culex pipiens complex through esterase overproduction

In most parts of China, mosquitoes have been subjected to organophosphate (OP) insecticide treatments since the mid-1960s, and resistance gene monitoring in the Culex pipiens complex (Diptera: Culicidae) started in only a few locations from the end of the 1980s. Many resistant alleles at the Ester locus have been found in field populations, including those commonly found around the world (Ester(B1) and Ester(2)), and those endemic to China (Ester(B6), Ester(B7), Ester(8), and Ester(9)). This situation is atypical, and may represent a complex situation for the evolution of insecticide resistance genes in China. To increase our understanding of the Chinese situation and our ability to manage resistance in the C. pipiens complex, a large study was performed. Twenty field populations were sampled from Beijing to Guangzhou. Bioassays with five insecticides (dichlorvos, parathion, chlorpyrifos, 2-sec-butylphenyl methyl carbamate, and propoxur) disclosed resistance levels variable according to the geographic origin, and up to 85-fold for dichlorvos. Six overproduced esterases were identified, including two that have not been previously described. Most of them were found in all samples, although at variable frequencies, suggesting variable selection or a transient situation, e.g., each one was recently restricted to a particular geographic area. The results are discussed in the context of recent alterations to insecticide campaigns, and of the evolution of resistance genes in Chinese C. pipiens populations.