互花米草总黄酮对小鼠免疫功能的影响

互花米草总黄酮(TFS)是从盐沼植物互花米草中分离得到的一种免疫活性物质。在研究TFS对小鼠免疫功能的影响时发现TFS156.25×10~(-6)ip qd×8导致由环磷酰胺引起的免疫抑制小鼠的胸腺重量增加。TFS154.25×10~(-6)sc qd×5还显著提高C_(57)/BL和昆明小鼠腹腔巨噬细胞的吞噬百分率和吞噬指数。TFS 3.125,12.5ug/ml在体外可明显促进由ConA诱导的~3H-TdR参入的淋巴细胞转化。     

VC对河蟹血清和组织中超氧化物歧化酶及磷酸酶活性的影响

研究了饲料中添加不同含量VC 对河蟹体内超氧化物歧化酶 (SOD)、碱性磷酸酶 (ALP)和酸性磷酸酶 (ACP)活性的影响 .结果表明 ,饲料中不添加VC 时 ,河蟹肝胰腺、卵巢、血清和肌肉各组织中SOD、ALP和ACP活性各异 ,其中SOD活性大小顺序为肝胰腺 >卵巢 >血清 >肌肉 ,ALP活性顺序为肝胰腺 >血清 >卵巢 >肌肉 ,而ACP活性则为肝胰腺 >血清 >肌肉 >卵巢 .饲料中VC 添加量分别 2 .5× 1 0 - 3 、5.0×1 0 - 3 、1 0 .0× 1 0 - 3 和 1 5.0× 1 0 - 3 (m m)时 ,与对照组相比 ,河蟹不同组织中SOD活性显著下降 (p <0 .0 5或 p <0 .0 1 ) ,而ALP、ACP这两种酶的活性却显著升高 (p <0 .0 5或 p <0 .0 1 ) .但它们的变化幅度不同 ,其中就肝胰腺、卵巢、血清和肌肉中SOD活性而言 ,VC 添加量为 1 5.0× 1 0 - 3 (m m )饲料组分别比对照组的低1 41 .3 4 %、1 2 5.94%、1 1 6.67%和 1 1 5.79%;ALP活性 ,VC 添加量为 1 0 .0× 1 0 - 3(m m)饲料组分别比对照组高 93 .0 %、77.5%、1 66.3 %和 2 66.4%;ACP活性 ,VC的添加量为 1 5.0× 1 0 - 3 (m m)饲料组分别比对照组高 1 3 0 .7%、2 3 7.4%、43 7.6%和 2 65.5%.饲料中VC 添加量为 (5.0～ 1 0 .0 )× 1 0 - 3 (m m )时 ,可有效地增强河蟹非特异性免疫能力 .此外 ,本实验还就VC     

北虫草菌Y3胞内与胞外多糖的免疫药理研究

对北虫草菌Ｙ３胞内与胞外多糖的免疫药理活性进行实验研究。结果表明,北虫草多糖可显著提高小鼠腹腔巨噬细胞吞噬功能,增强血清溶菌酶活力,提高小鼠肝、红细胞ＳＯＤ活力,并可对抗环磷酰胺引起的外周血白细胞数目下降。北虫草菌Ｙ３多糖对小鼠迟发型超敏反应与溶血空斑实验都有促进作用,提示其对特异性与非特异性免疫的增强作用。     

增加贝类染色体分裂相的方法初探

研究以太平洋牡蛎为材料 ,用低温同步化法和 8μg/m L的植物血球凝集素 (PHA- M)、50μg/m L 伴刀豆蛋白 A(Con A)两种外源凝集素分别处理其鳃 ,后用鳃做染色体滴片 ,10 % Giemsa染色后镜检 ,统计分裂相数。发现三种方法都能使分裂相比例增加 ,其中低温同步化法效果最好 ,可使分裂相比例由对照的 0 .7× 10 -4 升高到 6 .5× 10 -4 ,提高 8.3倍。PHA- M法使分裂相比例由对照的 0 .7× 10 -4升高到 5.5× 10 -4 ,提高 6 .8倍 ,Con A法使分裂相比例由对照的 0 .7× 10 -4升高到3.6× 10 -4 ,提高 4 .1倍。     

两种东风螺幼虫附着和变态的化学诱导研究

在持续24h作用下,12×10-3mol/dm3 K+可有效地诱导台湾东风螺(Babylonia formosae)和方斑东风螺(B.aerolata)的浮游幼虫90%以上完全变态.持续作用24h,15×10-3mol/dm3 K+对方斑东风螺幼虫有毒害作用,但作用12h可取得较好的诱导效果.增加K+诱导变态的稚贝能正常活动和摄食.增加K+诱导的幼虫变态率随幼虫平均壳高的增大而提高.L-多巴、肾上腺素和去甲肾上腺素在5.5×10-6～5.5×l0-5mol/dm3时对方斑东风螺幼虫的变态无诱导活性,而多巴胺在10-4mol/dm3时可诱导较12×10-3mol/dm3 K+约少一半的变态率.钾通道阻滞剂TEA对K+诱导两种东风螺幼虫变态无阻抑作用.根据添加KCl诱导幼虫变态试验结果,初步认为幼虫获得变态能力时的壳高,在台湾东风螺是860.2～1009.8μm,在方斑东风螺是849.6～956.0μm.两种东风螺的浮游幼虫均有变态延迟现象.     

花鲈仔、稚、幼鱼摄食习性与生长的研究

分析了花鲈仔、稚、幼鱼的摄食习性与生长.结果表明,在水温为15.5～16.5℃时,花妒仔鱼孵出约140h左右开口摄食,开口饵料为小型臂尾轮虫.全长10mm左右的仔鱼可摄食卤虫幼体,全长11mm左右的个体可摄食枝角类.对431尾仔、稚、幼鱼观察结果,在实验条件下其摄食率高达99.1%,胃饱满系数波动于2.38%～16.48%之间,日摄食指数在45%～60%.其摄食强度具明显的昼夜节律,以16:00～20:00胃饱满度最高.仔、稚鱼夜间基本不摄食,部分幼鱼个体少量摄食.仔、稚、幼鱼个体间生长速度具有一定的差异性.其体重与摄食量的关系符合直线方程y=0.1018+8.3261×10-2x;全长与体重的相关关系可用ω=1.6473×10-3L3.4743表示,全长与日龄的关系式为L_t=5.5242e1.9681×10-2D;体重与日龄的回归方程为ω=0.5836e6.9208×10-2D.     

质谱同位素稀释法用于海水痕量铅、镉和锌的分析及其前处理研究

本文应用双硫腙-氯仿萃取质谱同位素稀释法(IDMS)和洁净实验技术相结合,分析了海水中痕量Pb、Cd和Zn,准确度好,精密度优于±3%,Pb、Cd和Zn的检出限分别为6×10-11、6×10-12和2.4×1010g.文中还讨论了过滤、酸化及消解等样品的前处理对海水分析结果的影响.     

海洋假单胞菌纤溶酶的酶学性质的研究

从一株海洋假单胞菌中分离制备出一种具有纤溶活性的酶 ,对其酶学性质进行实验研究结果显示 :该酶的分子量是 2 1k D,等电点是 7.4～ 7.5 ;最适作用 p H是 8.0 ,最适作用温度是 5 0℃。该酶具有降解苯甲酰 - L -精氨酸乙酯盐酸盐 (BAEE)的活性 ,酶的动力学分析表明 :Km =0 .87mmol/ L,Vmax=1.80× 10 -3 mmol/ L s-1。     

三苯基氯化锡对黑褐新糠虾的毒性效应

于 1 992年 7月在青岛胶州湾西岸采集黑褐新糠虾 ,经实验室常年培养驯化后作为实验材料 ,研究了三苯基氯化锡 (TPTC)的急性毒性效应及其对糠虾繁殖、生殖周期和种群的慢性毒性影响。结果表明 ,在急性毒性实验中 ,TPTC对糠虾的半致死浓度为 2 5× 1 0 - 9g/L( 2 4hLC50 )和 1 5× 1 0 - 9g/L( 4 8hLC50 ) ;慢性毒性实验结果表明 ,TPTC能影响糠虾种群的世代繁殖 ,2× 1 0 - 9g/L的TPTC能使糠虾首次生育的年龄延迟 3d ,产幼总数比对照组减少80 %以上 ,1× 1 0 - 9— 2× 1 0 - 9g/L的TPTC能导致糠虾生殖周期延长 3— 4d ,在生殖期内的死亡率上升 30 %— 55% ,暴露于 0 2 5× 1 0 - 9— 2 0 0× 1 0 - 9g/LTPTC中的糠虾其子代的在 6× 1 0 - 9g/LTPTC中存活能力下降。可以认为 ,1× 1 0 - 9g/L的TPTC可导致糠虾种群的衰亡。     

5-羟色胺刺激长牡蛎排放精卵在四倍体诱导中的应用

本文报道了用 5 羟色胺催产出的长牡蛎精、卵 ,人工授精后诱导四倍体的实验结果 .结果表明 :在 2 6℃水温条件下 ,受精后 7min ,用 0 .5mg/dm3细胞松弛素B处理2 5min ,获得长牡蛎的胚胎四倍体 ,其诱导率为 1 6.7%,D形幼虫孵化率为 2 7.0 %;诱导效果优于采用常规解剖法 .注射 5 羟色胺刺激长牡蛎亲贝排放精、卵的有效浓度分别为 1× 1 0 -6 ～ 1× 1 0 -2 mol/dm3和 1× 1 0 -5 ～ 1× 1 0 -3mol/dm3.     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

INFORMATION FOR AUTHORS

<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,     

Evaluation of the Risk of Marine Slope Instability: A Pseudo-3D Approach for Application to Large Areas

This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.