黑Jun的生长和生态转换效率及其主要影响因素

采用室内流水模拟实验法测定了黑Ｊｕｎ的生长和生态转换效率,及其温度,摄食水平,体重和饵料生物种类的影响,黑Ｊｕｎ的特定生长率随摄食水平增大而减速增长;而特定生长率随温度升高或生态转换效率随温度和摄食水平增大均呈倒Ｕ型变化趋势;实验条件下的最大和最佳生长温度分别为１６．３℃和１５．８℃。维持摄食量和最佳摄食量分别为黑Ｊｕｎ体重的０．７９％和４．１０％。     

不同温度对中国对虾生长及能量收支的影响

研究了18～34℃6个不同恒温下中国对虾(Fenneropenaeus chinensis)的生长、饵料转化率及能量收支。结果表明,中国对虾的体重及能量特定生长率分别变动在1．22％～3．27％和1．33％～1．45％之间,在18～31℃温度范围内随温度升高而升高,34℃下则显著下降．对虾的摄食量及对饵料的消化率总体上随温度升高而升高,但在34℃下则有所降低;饵料重量转化率和能量转化率分别在28．99％～53．09％和15．70％～7．24％之间,总体上随温度升高而有所下降．根据拟合的多项式方程推算得到的中国对虾的最佳生长温度为29．7℃,生长能和呼吸能的变化主导着中国对虾的能量收支模式,随温度升高生长能占摄食能的比例逐渐降低,而呼吸能比例则逐渐升高。本研究表明,对虾在适宜温度下获得的较高生长率主要归因于较高的摄食量和食物消化率。     

鳜和乌鳢最适温度的研究

研究了体重47.2-540.2g的鳜和45.0-546.2g的乌鳢的最适摄食和生长温度。结果表明,鳜的最大摄食率随温度的上升而增大,在25-35℃之间形成“最适温度平台”,低温（10-25℃）时,乌鳢的最大摄食率随温度的上升而增加,在25-30℃之间形成“最适温度平台”,之后随温度的增加而下降,鳜的特定生长率随温度的增加而加快,在25-35℃“最适温度平台”,乌鳢的特定生长率受体重和温度的交互影响。     

温度对黑鲷(Sparus macrocephalus)能量收支的影响

在以玉筋鱼为饵料生物和最大摄食水平条件下,采用室内流水式实验,研究了黑鲷能量收支及温度对能量分配模式的影响。结果表明,黑鲷的摄食率、生长率、总代谢率和排泄率均随温度上升而呈减速增长趋势。不同温度条件下黑鲷的能量收支式为     

真(鱼岁)(Phoxinus phoxinus(L.))的能量收支各组分与摄食量、体重及温度的关系

在不同的摄食水平(饥饿—最大量)及温度(5—15℃)下,对1—5g的真(鱼岁)的摄食量、排粪量、排泄量、代谢量,生长量及生化组成作了测定。真(鱼岁)的最大摄食量随体重及温度增加而增加。食物能量平均有6.5％损失于粪便中,5.1％损失于排泄物中。摄食代谢随摄食量增加而增加。在同一温度下,特定生长率与摄食量的关系是一减速增长曲线。当摄食不受限制时,生长率随温度增加而增加;当摄食受限制时,生长率随温度增加而下降。鱼体的干物质含量及能量含量随摄食量增加而增加。     

摄食水平对不同性别食蚊鱼仔幼鱼生长发育的影响

在实验室27℃水温下,研究了少食、中食和饱食三个摄食水平对0至25日龄雌雄食蚊鱼(Gambusia affinis)的生长发育特征和饵料利用效率的影响。26d饲养实验结束后,对试验鱼摄食和生长指标、臀鳍分化、性成熟及饵料转换效率进行分析。结果显示:到臀鳍开始分化时,饱食组雄鱼的累计摄食总能量和生长速度开始小于雌鱼,且随日龄的增加差异加大;随摄食水平的增加,0日龄仔鱼到臀鳍分化和性成熟的时间缩短。至实验结束,各摄食组的雄鱼均形成发育完善的生殖足,性腺都达到成熟状态;而雌鱼性成熟迟于雄鱼,且其性成熟更易受到摄食水平的影响,饱食组只有约50%的个体达到性成熟,少食组的卵母细胞则均处在小生长期。随着摄食水平的增加,雌雄鱼的体长、体重和干物质特定生长率均呈明显上升趋势,而干物质饵料转化效率则呈明显下降趋势;实验结束时,雌鱼的生长指标和干物质饵料转化率均大于雄鱼。以上结果表明,伴随臀鳍的分化,食蚊鱼在摄食、生长、发育、性成熟和应对食物丰度变化上表现出显著的性别差异。       

海水和淡化水养殖凡纳滨对虾饲料蛋白需求量的比较研究

本研究从生长、饲料利用和体成分等指标综合评价饲料蛋白质含量对凡纳滨对虾的影响。研究发现,在海水养殖环境下,饲料蛋白水平对凡纳滨对虾的存活率、增重率、特定生长率、饵料系数、蛋白效率和虾体粗蛋白含量均有显著性影响(p<0.05)。摄食饲料蛋白含量38%的海养凡纳滨对虾有较高的存活率、增重率以及最高的特定生长率。饵料系数随蛋白含量的增加而减小,虾体粗蛋白含量随饲料蛋白水平升高而增加,而蛋白含量38%和41%实验组饵料系数和虾体粗蛋白含量均没有显著性差异(p>0.05)。淡化水养殖条件下,凡纳滨对虾的存活率随饲料蛋白水平的增加而提高,而增重率和特定生长率均在饲料蛋白含量35%实验组最高,饵料系数随蛋白含量的增加先减小后增大,蛋白含量35%实验组饵料系数显著小于其他实验组。海水养殖条件下,凡纳滨对虾的存活率、末体重、增重率、特定生长率和蛋白质效率均高于淡水养殖的对虾。对虾虾体粗蛋白、粗脂肪和粗灰分含量均随盐度升高而升高,而虾体水分随着盐度的升高而降低。     

日粮水平对中华鳖稚鳖生长的影响

于2001年12月购买当年繁殖的中华鳖(Trionyx sinensis)稚鳖(28．66-53．37g),在30℃水温下进行摄食-生长实验(实验时间为56d),设饥饿、1％、2％、4％和饱食5个日粮水平,研究了摄食水平对中华鳖稚鳖生长和转化效率的影响。方差分析表明：摄食水平对中华鳖稚鳖的特定生长率和转化效率均有显著影响。稚鳖的湿重、干重、蛋白质和能量的特定生长率均随摄食水平的增加呈二次曲线增加,摄食率(RL)-干物质特定生长率(SGRd)的关系模型可表示为：SGRa=-0．0832RL^2 1．0795RL-1．8779(n=25,r^2=0．906．F=105．46);当摄食率为6．97％、6．49％、6．08％和6．34％时,稚鳖湿重、干重、蛋白质和能量的特定生长率分别达到最大值。1％组的各项转化效率均显著低于2％和4％组,干重和能量转化效率显著低于饱食组;2％组的干重和能量转化效率显著高于4％和饱食组。     

摄食水平和投喂频率对大菱鲆幼鱼生长及生化成分的影响

以大菱鲆幼鱼(7.56±0.03 g)为试验对象,在水温17～19℃下,设计了4个摄食水平梯度(1.0％、1.5％、2.0％和饱食)和3个投喂频率梯度(1、2和3次·d-1),探讨了不同摄食水平和投喂频率对其生长及生化成分的影响.结果表明:随着摄食水平的升高,大菱鲆幼鱼的终末体重、相对增重率和摄食率显著升高(P＜0.05);特定生长率随摄食水平的增加呈线性升高;湿重、干重、蛋白质和能量转化效率出现先升高后降低的趋势;摄食水平对鱼体的体成分和组间表观消化率无显著影响(P＞0.05);不同投喂频率下,终末体重、相对增重率、特定生长率及转化效率呈先升高再降低的趋势,在2次·d-1时取得最大值;投喂频率对鱼体的体成分和组间表观消化率无显著影响(P＞O.05).     

小鳞Jian的维持日粮与转换效率

1998年8月在一个养虾场蓄水池利用网箱进行了小鳞Jian维持日粮与转换效率的研究,小鳞jian生长率（GR）与日粮（DR）的关系可表示为GR＝140．37DR－24．03;食物转换效率和能量转换效率分别为13．96％和16．12％,从生长率和特定生长率计算的小鳞Jian维持日粮分别为体重的17．12％,和20．39％,表明从生长率和特定生长率计算维持日粮可能会导致不同的结果,当日粮水平低于3．30％时,小鳞Jian生长表现异常,意味着它可能利用了网采浮游动物以外的其它食物源。     

白蚁与动物及微生物的共生类型及其机制

综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生（宾主共栖和异种共栖）、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌（原生动物、细菌、真菌和放线菌）和外生菌（蚁巢伞菌等）间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用（如纤维素酶）及今后研究物种间的协同进化提供了基础资料。     

New amino-dithiaphospholanes and phosphoramidodithioites and their rhodium and iridium complexes

New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn₂NPSCH₂CH₂S^a(P-S^a) (Bn = benzyl, 4), Bn₂NPSCHCHS^a(CH₂)₃C^aH₂(P-S^a)(C^a-S^a) (6) and Bn₂NP(4-XC₆H₄OMe)₂ (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)₂] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl₂Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the ν_CO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The ¹J_PRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the ¹J_PSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh₃. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh₃.     

Astrocytes and Synaptosomes Transport and Metabolize Lactate and Acetate Differently

Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.     

Rapporteur report: Basics and technology and metrology and standards

The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.     

Relative and combined effects of ethanol and protein deficiency on strontium and barium bone content and fecal and urinary excretion

To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.     

Prostaglandin and thromboxane production by human and guinea-pig macrophages and leucocytes

The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE₂, PGD₂, PGF_2α, TXB₂ and 6-keto-PGF_1α. In all types studied PGE₂ and TXB₂ were the major products formed. The identification of PGE₂ and TXB₂ was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.     

Chemokines and cytokines: axis and allies in asthma and allergy

Allergic asthma can be precipitated by many factors. For the atopic person, fungus, pollen, dust mites, cockroach antigens, and diesel exhaust are all agents that may trigger an allergic attack. Cytokines and chemokines are integral mediators of fungal asthma. From the earliest time points, they recruit and activate the cells required for the clearance of fungus as well as being critical factors involved in the immunopathology of this disease. In the final analysis, it is clear that these mediators can act to the benefit or the detriment of the host.     

Oxidation and nitration of ribonuclease and lysozyme by peroxynitrite and myeloperoxidase

In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.