复方新诺明在鲈鱼体内的药物代谢动力学研究

首次报道了用高效液相色谱法研究鲈鱼口服复方新诺明的药物代谢动力学特征。结果表明 ,鲈鱼单次口服剂量为200×10-6的复方新诺明后 ,其血液药物浓度 时间数据符合一室开放动力学模型。药物代谢动力学参数 :吸收速率常数 (ka)为0.096h -1、达峰时间 (Tmax)为21.479h,峰浓度 (Cmax)为50.768μg/ml、吸收半衰期 (T(1/2)Ka)为7.250h、消除半衰期 (T(1/2)K)为38.299h,药时曲线下面积 (AUC)为4138.400(mg·h)/L。鲈鱼口服药物0.5h后在肌肉、血液、肝脏、肾脏4种组织中就可以检测到药物的存在。药物在16h采样点4种组织里的浓度达最高。药物在肌肉、血液、肝脏中的平均回收率约80%～90 % ,该方法的检测限可达0.05×10-6。     

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。     

磺胺甲基唑和恩诺沙星在日本囊对虾体内的药代动力学研究

为了研究磺胺甲基唑(Sulfamethoxazole, 简称SMZ)和恩诺沙星(Enrofloxacin, 简称ERFX)在日本囊对虾(Marsupenaeus japonicus)体内的药物代谢动力学特点, 在水温21℃±0.5℃, 盐度29.91 的条件下, 应用萃取、液相测定和反相高效液相色谱法(RP-HPLC)对药物平均回收率、主要动力学参数及在3种组织中的半衰期进行了测定, 检测数据经药物代谢动力学软件3p97 进行研究。结果表明, SMZ 和ERFX 在对虾肝脏、肌肉和血淋巴的平均回收率分别为90.09％, 88.92％, 84.84％和89.14％, 86.04％,91.77％。药物代谢动力学分析表明, SMZ 单次腹部肌肉注射日本囊对虾, 其肝脏药时数据符合二室模型, 肌肉和血淋巴药时数据符合一室模型,半衰期为19.1284, 4.5799, 9.1855 h。ERFX 单次腹部肌肉注射日本囊对虾, 其肌肉药时数据符合二室模型, 肝脏和血淋巴药时数据符合一室模型。半衰期分别为15.16, 16.83, 17.19 h。通过两种药物的代谢特征比较分析表明, SMZ 在肌肉中吸收较ERFX 快, ERFX在血淋巴和肝脏中吸收较SMZ 快。根据SMZ 和ERFX 在21℃±0.5℃的条件下的主要动力学参数及3种组织内消除半衰期, 建议SMZ 在日本囊对虾的休药期不少于10 d, ERFX 的休药期不少于12 d。     

诺氟沙星2种不同给药方式在中国对虾体内的残留及消除规律

在水温(28±1)℃条件下,诺氟沙星药浴给药(10 mg·L-1)和药饵给药(30 mg·kg-1)连续5 d后,利用反相高效液相色谱法(RP-HPLC)分析诺氟沙星在中国对虾体内的残留及消除规律。结果表明,2种给药方式下,诺氟沙星在中国对虾肝胰腺、肌肉等组织中的分布和消除差别较大。药浴给药后中国对虾肝胰腺和肌肉中药物达峰时间分别为9和24 h,药峰浓度分别为1.36,0.25μg.g-1,消除半衰期分别为29.87和40.19 h;药饵给药后中国对虾肝胰腺和肌肉中药物达峰时间均为4 h,药峰浓度分别为0.79,0.113μg.g-1。2种给药方式下药物在对虾肌肉中的消除曲线分别为C(t)浴=0.2449e-0.4138t和C(t)饵=0.4066e-0.5364t;消除半衰期分别为40.19和31.01 h。根据诺氟沙星在水产品中的残留限量标准(50μg·kg-1),2种给药方式下,肌肉中诺氟沙星浓度均在给药后24 h低于此残留限量;肝胰腺中浓度经药浴给药后216 h低于此残留限量,药饵给药后96 h低于此残留限量。药浴给药和药饵给药后,肌肉中药物浓度达到此残留限量的休药期分别为3.84和3.90 d。     

温度和限食对花鲈早期幼鱼摄食与生长的影响

为探索北方人工繁育花鲈(Lateolabrax maculatus)幼鱼冬季生长最佳温度及投饵模式,本实验首次采用温度和限食双因素处理来研究花鲈幼鱼的补偿生长规律。实验设置3个温度水平(20℃、16℃和12℃)和2个投喂水平(100%投喂和50%投喂),其中A组(20℃和100%投喂)为对照组,B组(16℃和100%投喂)、C组(12℃和100%投喂)、D组(20℃和50%投喂)、E组(16℃和50%投喂)和F组(12℃和50%投喂)为处理组。实验分2个阶段:第一阶段为30 d的处理阶段;第二阶段为20 d的恢复阶段。结果表明,花鲈幼鱼在不同温度及限食条件下具有不同的补偿生长能力和补偿生长机制。B组通过提高饵料转化率实现了超补偿生长;C组也是通过提高饵料转化率达到了完全补偿生长;D、E组则通过提高摄食率实现了完全补偿生长;F组的花鲈幼鱼则通过提高饵料转化率实现了部分的补偿生长。综合考虑花鲈幼鱼冬季培育成本及其生长,建议北方花鲈幼鱼越冬培育温度为16℃,投喂模式为100%投喂。     

三聚氰胺在大菱鲆体内的代谢消除规律研究

采用LC-MS/Ms 法研究三聚氰胺在大菱鲆(Scophthalmus maximus)体内的代谢消除规律.三聚氰胺以5g/kg浓度添加到饲料中,连续投喂大菱鲆30d,停药后,对大菱鲆肌肉、肝脏、肾脏组织残留的三聚氰胺进行测定.结果表明:三聚氰胺能够在大菱鲆肌肉、肝脏、肾脏各组织中富集并消除,最高血药浓度由高到低依次为...     

人工繁育花鲈早期发育形态特征与仔鱼培育技术研究

对人工繁育的花鲈(Lateolabrax maculatus)早期发育阶段的形态特征及苗种培育技术进行了观察与研究。结果表明:在水温17±1℃、盐度30、pH8.0、溶解氧7.0mg/L的条件下,花鲈受精卵经过72h完成胚胎发育过程。在胚后发育阶段,根据卵黄囊体积、鳍条发育情况,将花鲈前期发育划分为仔鱼期、稚鱼期、幼鱼期;仔鱼期又可分为前期仔鱼和后期仔鱼。本文对培育过程中死亡率较高的仔鱼期进行了详细观察,发现在水温16~17℃,盐度30的海水中培育,初孵仔鱼至5日龄(day post hatching,dph)仔鱼是前期仔鱼,6~35dph为后期仔鱼。花鲈个体之间发育速度差异较大、仔鱼之间的残食现象是整个培育过程中比较明显的特征,这些特征与冬季水温较低造成的越冬困难一起限制了花鲈苗种的全人工繁育技术的建立。     

黄芩苷在中国对虾体内的代谢及残留消除规律研究

在(24±1)℃下,中国对虾连续7 d给予100 mg/kg黄芩苷药饵,用高效液相色谱法(HPLC)测定对虾血液及其它组织中的黄芩苷含量,建立适合中国对虾体内黄芩苷含量的测定方法,研究黄芩苷在中国对虾不同组织中的残留消除规律.结果表明,HPLC法黄芩苷与杂质分离良好,4个浓度水平的黄芩苷在不同组织中的平均回收率在80.57%～96.25%之间,日内精密度在3.26%～5.85%之间,日间精密度在3.88%～5.73%之间.与其它给药方式相比,黄芩苷药饵给药吸收较慢,在血液、肝胰腺、肌肉、鳃中的达峰时间(Tmax)依次为6,3,6,3 h;黄芩苷在不同组织中的分布为肝胰腺>鳃>血液>肌肉.黄芩苷在肝胰腺、鳃、肌肉、血液中的消除半衰期(t1/2β)分别为29.62,27.50,25.20,23.73 h,消除速率从快到慢依次为血液>肌肉>鳃>肝胰腺;黄芩苷残留较少,在肌肉和血液中5 d已降到检测限以下,肝胰腺及鳃7 d降到检测限以下.本试验为含黄芩苷的药物的应用提供参考.     

甲基睾丸酮在尼罗罗非鱼(Oreochromis niloticus)肌肉中的代谢和消除规律研究

在实验水温(28±2)℃条件下,以60mg/kg单剂量甲基睾丸酮对尼罗罗非鱼混饲口灌给药后,采用超高效液相色谱-串联质谱联用(UPLC-MS/MS)法测定尼罗罗非鱼肌肉中的药物水平,研究甲基睾丸酮在尼罗罗非鱼肌肉中的代谢及消除规律。结果表明,肌肉中药物浓度时间数据符合一级吸收二室开放模型,主要药代动力学参数达峰时间T(peak)为3.04h,质量浓度C(max)为33.331ng/g,消除半衰期T(1/2)β为23.073h。肌肉中甲基睾丸酮浓度24h内呈指数型下降,具有较高的消除速率,其后消除得较缓慢,消除方程符合C=46.18e0.101t。29d后罗非鱼肌肉中甲基睾丸酮水平在美国FDA的检测限0.8ng/g以下,给药120d后肌肉中检测不到甲基睾丸酮残留。     

头孢拉定、诺氟沙星及罗红霉素在中华鳖(Pelodiscus sinensis)日本品系体内残留代谢的比较研究

应用液相色谱-串联质谱技术比较研究了头孢拉定、诺氟沙星及罗红霉素3种渔药在中华鳖(Pelodiscus sinensis)日本品系体内的残留代谢规律。在(25.0±2)°C饲养条件下,通过连续7d对健康中华鳖日本品系投喂分别含有30mg/kg头孢拉定,300mg/kg诺氟沙星或30mg/kg罗红霉素的药饵后,比较分析了3种渔药在中华鳖日本品系体内各组织中的浓度变化。结果表明:头孢拉定和诺氟沙星的代谢符合一室消除模型,罗红霉素的代谢符合二室消除模型。头孢拉定在中华鳖日本品系血液、肌肉和肝脏中消除半衰期T1/2(Ke)分别为6.132h、9.002h和10.132h。诺氟沙星在中华鳖日本品系血液、肌肉和肝脏中消除半衰期T1/2(Ke)分别为22.526h、39.715h和41.585h。罗红霉素在中华鳖日本品系血液、肌肉和肝脏中消除半衰期T1/2(β)分别为38.54h、15.65h和100.5h。建议选用肝脏作为今后中华鳖质量安全残留监控靶组织。     

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。     

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.     

Estimation of Sediment Properties during Benthic Impact Experiments

Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.     

A Tidal Flow Model for the Gulf of Kachchh, India

A vertically integrated model has been used to study the tidal circulation and currents in the Gulf of Kachchh along the west coast of India. The model is fully nonlinear and uses a semiexplicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model is forced by prescribing the tides along the open boundary of the model domain. The flow is simulated both with and without the presence of the proposed tidal barrage across the Hansthal Creek in the Gulf of Kachchh. The results show a considerable change in the behavior of the tidal flow in the presence of the barrage.     

利用中国GF-3卫星SAR和HY-2A卫星微波散射计的首次台风联合定量观测

<正>The typhoon,as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall,is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia.It can be easily detected by space-borne sensors operated at microwave,visible or infrared bands(Liu et al.,2014).Synthetic Aperture Radar(SAR)is     

离子交换—原子吸收光谱法测定海水中痕量铜、铅、锌、镉、铁、锰

本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8％之间,回收率为90—102％。     

Biogeochemistry of Mangrove Soil Organic Matter: a Comparison BetweenRhizophoraandAvicenniaSoils in South-eastern Brazil

Soil core samples fromRhizophora mangleL. andAvicennia schauerianaStapf & Leech forests from south-eastern Brazil were analysed for their total organic matter content and their sugars, amino acid and amino sugars composition. Organic carbon and nitrogen contents were higher inAvicenniathan inRhizophorasoils. The contribution of sugars and amino acids to the total organic carbon pool was constant with depth inRhizophorasoils whereas inAvicenniasoils it increased. Spectral distribution of sugars and amino acids showed a dominance of Ca-affine monomers, particularly acidic amino acids, and the sugar arabinose. Biogeochemical indicators derived from ratios of individual sugar and amino acid monomers confirm previous studies which showed that organic matter in both soils is mainly of mangrove origin. The results further suggest accumulation of organic matter inRhizophorasoils and a continuing degradation of organic matter inAvicenniasoils. The latter may thus release more nutrients to adjacent ecosystems thanRhizophorasoils.     

A review of orange roughy Hoplostethus atlanticus fisheries,estimation methods,biology and stock structure

Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at 22 – 40 years), and to have exceptionally low natural mortality (M = 0.045–0.064 year^?1) and slow growth rates (K = 0.055–0.070 year^?1). In addition, they spawn large eggs and have low fecundity. These factors combine to make orange roughy highly susceptible to overfishing; most stocks are below 30% of pristine levels. Assessments are obtained from indices of catch rate and trawl, acoustic and egg surveys. Acoustic estimates are the most direct, but are confounded by the species' low target strength (?50 to ?53 dB)–attributable to the wax-filled swim bladder. Extracellular wax esters are stored in abundance and comprise mostly mono-unsaturated fatty acids, with low concentrations of the ω-3 fatty acid family. This unusual composition (resultant from the species' diet) ensures neutral buoyancy. Stock separation has been inferred mainly from biological studies, but genetic studies have also found differences among stocks within New Zealand and Australia. Deep-water habitat may be damaged by trawling operations and may take many years to recover, so in some quarters there is a call for a portion of suitable habitat to be set aside for preservation. Although Namibian orange roughy are shallower, smaller and younger than those in other stocks, the Namibian fishery sustained high catches for only a few years before quotas were reduced, from 12 000 to 1 875 tons. Three management lessons are suggested for developing orange roughy fisheries based on the Namibian experience: (1) imposition of catch limits during exploratory fishing; (2) starting the acoustic surveys earlier in the fishery, if possible; (3) greater reliance on trends in catch rate until a survey series has been established.