不同温度下氟苯尼考在大菱鲆体内的药代动力学研究

研究了14和17℃2种不同养殖温度下,氟苯尼考在健康大菱鲆(Scophthalmus maximus)体内的药代动力学特征。以15mg/kg BW的剂量经静注和口灌2种方式给药后,于0.25、0.5、1、2、4、6、8、12、16、24、48和96h采集血液样品,采用Agilent1200型高效液相色谱仪测定样品中药物的含量,药时数据采用DAS2.0自动药动学软件进行分析。研究显示,14和17℃下,静注给药后的消除相半衰期(t1/2β)分别为18.20和12.46h,表观分布容积(Vd)分别为0.03和0.11L/kg,清除率(CL)均为0.02L/(h·kg)。口灌给药后血药浓度均在12h达到峰值,分布相半衰期(t1/2α)分别为2.84和4.08h,消除相半衰期分别为14.48和12.45h,生物利用度(F)分别为17.02%和18.24%。研究结果表明,温度升高会加快大菱鲆对氟苯尼考的吸收、体内分布和消除,提高口灌方式氟苯尼考利用效率。结合氟苯尼考药效学研究结果,提出给药方案:14℃时,大菱鲆口灌给药剂量25mg/kg BW,每日一次;17℃时,大菱鲆口灌给药剂量22mg/kg BW,每日一次。     

氟苯尼考3种不同给药方式在中国明对虾体内的药代动力学研究

用高效液相色谱法研究静注、肌注和口服氟苯尼考在中国明对虾(Fenneropenaeuschinensis)体内的药代动力学特征,所得数据用MCP-KP程序分析。结果表明,3种给药方式的血药经时过程均符合二室开放模型,符合一级吸收二项指数方程,血窦注射、肌肉注射、口服药饵的时间对药物质量浓度的理论方程分别是:C血注=16.38e-2.58t 0.32e-0.1t,C肌注=18.7e-2.57t 0.26e-0.12t,C药饵=15.08e–1.49t 0.65e-0.09t–15.74e–10.38t。主要药物代谢动力学参数分别是:吸收半衰期(t(1/2)α)为0.269,0.270和0.465h,消除半衰期(t(1/2)β)为6.921,6.494和7.903h,表观分布容积(Vβ)为1.287,1.293和2.421L/kg,总体清除率(Cs)为0.129,0.138和0.213L/(h·kg),药时曲线下总面积(Au,c)为0.755,0.681和0.666L/(h·kg)。肌肉注射和口服给药的生物利用度(F)分别是90.20%和97.58%。     

紫外线照射剂量对九孔鲍胚胎及幼虫的影响

采用不同的紫外线照射剂量的海水诱导九孔鲍产卵,观察其对卵子的受精率、畸形率和孵化率的影响.紫外线照射剂量的配制方法是:用紫外线照射过的最大剂量的海水与新鲜海水混合配制出各种剂量的海水.实验把雌亲鲍分成7组,每组20只,分别用紫外线照射剂量为0(对照组)、450、600、750、900、1 050和1 200mW.h/dm3的海水进行刺激产卵.试验重复3次.结果表明,紫外线照射剂量在1 200mW.h/dm3以内,对卵子的受精率影响不大;紫外线照射剂量在750mW.h/dm3以内,对卵子的畸形率影响不大,但在900~1 200mW.h/dm3,对卵子的畸形率影响很大;紫外线照射剂量在600mW.h/dm3以内,对卵子的孵化率没有什么影响,但在750~1 200mW.h/dm3,对卵子的孵化率影响很大.综合考虑卵子的受精率、畸形率和孵化率,九孔鲍催产的适宜的紫外线照射剂量应为450~750mW.h/dm3.     

恩诺沙星在人工感染溶藻弧菌的三疣梭子蟹体内的代谢动力学

应用反相高效液相色谱法,研究了人工感染溶藻弧菌的三疣梭子蟹口灌恩诺沙星（给药剂量为10 mg/kg）后,其血淋巴、肌肉、肝胰腺等组织的药代动力学规律.结果表明,恩诺沙星在感染溶藻弧菌的三疣梭子蟹体内3种组织中的药物时量曲线关系均符合一级吸收二室模型.恩诺沙星在血淋巴、肌肉和肝胰腺中的主要药代动力学参数：给药后出现最高血药质量浓度的时间（Tp）为3.200、4.120、0.233 h,给药后的最高血药质量浓度（Cmax）为0.710、1.009、3.474μg/cm3,药时曲线下总面积（AUC）为22.710、39.632、146.727μg/（cm3.h）,表观分布容积（Vd）为11.231、7.514、2.813 dm3/kg,消除半衰期（t1/2β）为102.124、57.661、66.390 h.恩诺沙星在感染三疣梭子蟹体内吸收迅速,分布广泛,组织穿透力极强.代谢物环丙沙星在血淋巴、肌肉、肝胰腺3种组织中的含量均处于较低水平.感染三疣梭子蟹口灌恩诺沙星合理的休药期应不少于18 d.     

氟苯尼考在中国对虾体内消除规律的研究

采用口服药饵的方法研究氟苯尼考在中国对虾体内的代谢动力学和残留规律,用反相高效液相色谱测定氟苯尼考在对虾组织中的含量。结果表明:中国对虾连续5 d口服氟苯尼考药饵,高、低2种剂量(16 mg/kg.d和8 mg/kg.d)组的药物代谢动力学变化趋势相似,高剂量组的组织中药物含量远高于低剂量组,肝脏中的药物浓度远大于肌肉中的药物浓度,氟苯尼考在对虾体内的消除速度较快,低剂量组的消除速度比高剂量组快,2种剂量的药物在对虾肌肉中的消除曲线方程分别为C(t)高=0.247 3 e-0.015 5 t和C(t)低=0.118 2 e-0.043 2 t,消除半衰期分别为44.71 h和16.04 h。在本试验条件下,高、低2种剂量的氟苯尼考在肌肉组织中降到0.01,0.05,和0.1μg/g不同浓度水平的理论时间为:207,103,58,57,20和4 h。     

长江冲淡水区细菌生产力研究

为了解细菌在长江口冲淡水区生态系营养动力学过程中的重要作用,笔者于1997年10月10日至20日,1998年5月14日至6月1日在观测海区以及在绿华山海域设置大水体围隔生态系实验装置进行细菌生产力的现场观测研究.结果表明,秋季观测海区平均细菌生产力(C)为(1.44±1.30)μg/(dm3·h),高值出现在测区中部的A₃,B₃和C₃站.春季测区表层细菌生产力(2.43±1.22)μg/(dm3·h)高于底层(1.01±0.43)μg/(dm3·h),高值出现在测区中部的A₃和B断面诸站.秋、春季平均细菌生产力相当于浮游植物初级生产力的23%.秋季和春季表层细菌数量分别为(5.22×108±0.88×108)个/dm3和(1.97×108±1.10×108)个/dm3.1998年5月18日至6月1日在围隔实验点的自然海区中细菌生产力变幅范围为0.13～5.79μg/(dm3·h),平均值为(2.47±1.60)μg/(dm3·h).围隔装置内加可溶性磷(PO₄3-)实验,春季细菌生产力由1.28μg/(dm3·h)增长至32.20μg/(dm3·h),其增长幅度低于秋季1.43～43.47μg/(dm3·h).油污染实验中细菌生产力由6.61μg/(dm3·h)增长至37.97μg/(dm3·h),呈逐日上升趋势.     

土霉素在牙鲆体内的药代动力学研究

采用高效液相色谱法为定性、定量手段,研究土霉素在牙鲆(Paralichthys olivaceus)体内的药代动力学过程,采用DAS(Drug and Statistics)药代动力学程序对数据进行分析.结果表明,牙鲆单剂量口服土霉素后(200 mg/kg),血药经时过程符合二室模型,主要动力学参数如下:吸收半衰期(T(1/2)a)为10.043 h,单剂量给药后牙鲆体内出现最高质量分数的时间(Tmax)为4.000 h,单剂量给药后牙鲆体内最高血药质量分数(Cmax)为0.54 mg/L,药时曲线下总面积(CAU0-72)为17.15 (mg*h)/L,吸收速率常数(Ka)为0.223,消除速率常数(k)为0.476 h-1.牙鲆肌肉中土霉素的经时过程符合一级吸收一室模型,主要动力学参数:T(1/2)a为74.893 h,Tmax为4.000 h,Cmax为3.58 mg/L,CAU0-72为148.56 (mg*h)/L,Ka为0.731,k为2.991 h-1.牙鲆肝脏中土霉素的经时过程符合一级吸收一室模型,主要动力学参数:T(1/2)a为31.376 h,Tmax为4.000 h,Cmax为13.78 mg/L,CAU0-72为494.14 (mg*h)/L,Ka为0.876,k为4.940 h-1.     

氟苯尼考在三疣梭子蟹(Portunus trituberculatus)疾病模型内的代谢动力学

为了解健康和疾病条件下药物在三疣梭子蟹(Portunus trituberculatus)体内的代谢差异,在构建三疣梭子蟹溶藻弧菌疾病模型的基础上,按25mg/kg剂量分别给健康和患病三疣梭子蟹单次口灌氟苯尼考后,采用高效液相色谱法测定了其肝胰腺、肌肉和血浆中的药物浓度,药时数据应用3P97药代动力学软件拟合。结果显示:氟苯尼考在健康和患病条件下三疣梭子蟹相同组织中的药时曲线形态相似,三种组织的药时数据均符合带时滞的一级吸收二室开放模型;肝胰腺吸收药物最快,肌肉次之,血浆最慢;与健康组相比,患病蟹肝胰腺、肌肉、血浆三种组织对氟苯尼考的吸收和消除速度明显减慢,达峰时间推迟,半衰期延长,清除率减低,最高药物浓度下降,表观分布容积和药时曲线下总面积变大。说明疾病使氟苯尼考在三疣梭子蟹体内的吸收、分布、代谢和消除均发生了显著变化,建议患病三疣梭子蟹口服氟苯尼考的休药期至少10d。     

肌注和口服药饵麻保沙星在日本对虾体内的药代动力学比较

在水温(25±0.6)℃条件下,分别以10、10和30 mg/kg剂量给健康日本对虾血窦注射、肌注和口服药饵麻保沙星后,用高效液相色谱法测定药物浓度,采用DAS2.0药动学软件对血药浓度进行分析,主要比较了肌注和口服药饵两种给药方式下麻保沙星在日本对虾体内的药代动力学差异。结果显示,血窦注射给药后,麻保沙星在日本对虾体内药物动力学最佳模型为无级吸收二室开放模型,表达方程为:C血窦注射=13.373e–1.396 t+8.28e–0.062 t;肌注和口服药饵麻保沙星后,在日本对虾体内的代谢过程均符合一级吸收二室开放模型,表达方程为C肌肉注射=15.521e–1.153t+7.90e–0.059t-23.421e–11.73t,C口服药饵=17.486e–0.33t+3.01e–0.051t-20.496e–0.408t。与口服药饵给药后药代动力学参数比较,肌注给药后的tmax(0.25 h)、t1/2Ka(0.059 h)、t1/2α(0.601 h)和t1/2β(11.769 h)均小于口服药饵给药的tmax(0.5 h)、t1/2Ka(1.697 h)、t1/2α(2.103 h)和t1/2β(13.535 h),且Cmax(20.7858 mg/L)和F(99.56%)均大于口服药饵给药Cmax(12.4774mg/L)、F(69.68%)。结果表明,肌注麻保沙星在日本对虾体内的吸收、分布和消除均快于口服药饵给药,且比口服给药吸收较完全。本实验将药动学参数与抗菌后效应(PAE)和最小抑菌浓度(MIC)相结合来探讨麻保沙星的给药方案,建议在治疗日本对虾细菌性疾病时,肌注14.30 mg/kg,每隔13.6 h一次;口服19.17 mg/kg,每隔11.8 h一次。     

九孔鲍MSTN基因cSNP多态性及与生长性状关联分析

九孔鲍(Haliotis diversicolor supertexta)是中国南方具有较高经济价值的养殖贝类。肌肉生长抑制素(Myostatin, MSTN)是转化生长因子β超家族(TGF-β)中参与动物肌肉生长的重要调控因子, 因此MSTN基因是动物遗传改良的重要候选基因。为探究九孔鲍MSTN基因的多态性及其生长相关性, 实验采用PCR产物直接测序方法对九孔鲍MSTN基因进行单核苷酸多态性(SNP)筛选, 对MSTN基因SNP与体质量、壳长、壳宽进行关联性分析, 运用实时荧光定量PCR (qRT-PCR)技术检测九孔鲍MSTN基因不同基因型的表达水平。结果显示: 在九孔鲍MSTN基因中共筛选出9个SNP位点。SNP位点与生长性状关联分析发现, 九孔鲍MSTN基因编码区SNP位点g909C>T发生C/T同义突变与九孔鲍体质量、壳长、壳宽显著相关。TT基因型九孔鲍的体质量显著高于CC基因型和TC基因型个体; TT基因型的壳长、壳宽显著高于CC基因型(p<0.05)。通过qRT-PCR检测显示, 在九孔鲍MSTN基因SNP位点g909C>T的3种基因型中, TC和CC基因型的基因表达量显著高于TT基因型(p<0.05)。研究结果表明MSTN基因SNP位点g909C>T可作为九孔鲍标记辅助选择育种重要候选标记。     

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.     

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.     

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.     

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.