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1.
在13℃条件下,采用单剂量灌服的方法给黑鲪100mg/kg体重的磺胺甲噁唑(SMZ),以HPLC法测定黑鲪肌肉中的药物浓度,用DAS2.0药物代谢动力学分析软件处理药时数据,结果表明:在13℃条件下,黑鲪单次灌服SMZ的药动学房室模型符合无时滞的二房室模型,分布半衰期t_(1/2α)为5.947h,消除半衰期t_(1/2β)为12.882h,达峰时间T_(max)为8h,峰值C_(max)为40.880μg/g.经过71d的代谢,肌肉中的药物含量下降到无公害食品中所规定的<0.1mg/kg鱼体重.  相似文献   

2.
采用高效液相色谱法,研究了(24.5±0.2)℃水温条件下单次静注和口服给药后噁喹酸在健康大菱鲆体内的代谢动力学规律.结果显示,大菱鲆单次口服嗯喹酸(20mg/kg)后,药物在血浆中经时过程符合一级吸收二室开放模型,表达方程为C口服 =2.059e-0.062t +0.645e-0.023t-2.704e-0.202t,单次静注嗯喹酸(10mg/kg)后,药物在血浆经时过程符合无级吸收二室开放模型,表达方程为C静注=12.284e-0.144 +0.284e-0.027t.血浆中的主要药动学参数,静注的t1/2α (4.813 h)、t1/2β(25.441h)、tmax(0.083 h)均小于口服给药(11.26、30.212、6h).结果表明,静注嗯喹酸在大菱鲆体内的吸收、消除速度,达峰时间均快于口服给药.根据本实验的结果,嗯喹酸的合理给药方案为:建议口服给药按鱼体重21.41mg/kg,每日1次给药,连用5~7 d.  相似文献   

3.
利用高效液相色谱技术对江蓠(Gracilariaceae)中类菌孢素氨基酸(MAAs)进行了分析,并采用响应面分析法对MAAs物质的提取工艺进行优化研究。根据正交旋转组合试验设计原理,采用四因素五水平的响应面分析法,依据回归分析确定各因素的显著程度及最优工艺条件。结果表明,江蓠中MAAs的主要成分为porphyra-334;提取温度、浸提时间、甲醇浓度及液固比为影响MAAs物质提取的显著因素。通过多元二次回归拟合模型响应面分析,得到最优工艺条件:提取温度48.12℃,液固比34∶1,甲醇浓度25%,浸提时间1.85 h,优化条件下预测提取率为4.943 mg/g;试验值为4.893 mg/g,试验值与预测值吻合较好,响应面回归模型的准确性得到验证。  相似文献   

4.
本研究以三疣梭子蟹Portunus trituberculatus为研究对象,通过急性和亚急性暴露试验,研究Cd2+对其肝胰腺和鳃的毒性效应。结果表明:Cd2+对三疣梭子蟹的48、72和96 h半致死质量浓度分别为6.55、4.33和3.12 mg/L,Cd2+对三疣梭子蟹的安全质量浓度为0.31 mg/L;在安全质量浓度和渔业水质标准质量浓度(<0.005 mg/L)下,随着暴露时间的延长,三疣梭子蟹的肝胰腺和鳃中HSP70的表达量都出现“先升后降”的趋势,与对照组相比,鳃中HSP70的表达量比肝胰腺的变化明显。在安全质量浓度以下,三疣梭子蟹的存活率并没有明显的变化,但是HSP70的诱导表达反映机体受到Cd2+的胁迫。因此HSP70基因可用作低质量浓度Cd2+污染检测的生物标志物。  相似文献   

5.
重金属Cd2+、Cu2+对文蛤的急性毒性   总被引:1,自引:0,他引:1  
用静态急性毒性试验的方法,研究24h、48h和96h内重金属离子Cd2+、Cr+对文蛤的毒性影响.结果表明:Cd2+对文蛤的24h、48h、96h LC50和安全浓度分别为197.35mg/L、40.47mg/L、13.18mg/L和0.13mg/L;Cu2+的24h、48h、96h LC50和安全浓度分别为1.66m...  相似文献   

6.
INTRODUCTIONRecently ,moreandmoreattentionhasbeengiventotheexploitationandutilizationofmarinebioresourcebythestate .Ithasbeenwidelyrecognizedthatmarineorganismsduetotheiruniquesurvivalenvironmentcanproducenovelbioactiveproducts,whichhaven’tbeenfoundint…  相似文献   

7.
以5日龄中华鳖稚鳖为实验动物,采用静水停食实验法,在水温(27.4±1.3)℃条件下,开展了Hg2+、Cr6+、Cu2+、Zn2+对中华鳖稚鳖的急性毒性和加和等毒性强度联合毒性试验。结果表明,4种重金属离子对中华鳖稚鳖均呈现以蓄积为主导的急性毒发效应,Cr6+、Zn2+对中华鳖稚鳖的急性致毒高峰期明显滞后于Hg2+、Cu2+;4种重金属离子毒性大小依次为Hg2+、Cu2+、Cr6+、Zn2+,其对中华鳖稚鳖96h的半致死质量浓度分别为5.98、16.42、28.90和91.88mg/L;所构建的中华鳖稚鳖累积死亡概率与重金属质量浓度和实验时间之间的数学模型,以及半致死时间-质量浓度回归方程,可作为侦查和分析重金属离子排放时间和致中华鳖稚鳖大量死亡时间的重要计算工具;Hg2+、Cr6+、Cu2+、Zn2+离子两两组合在加和等毒性强度下对中华鳖稚鳖96h联合急性毒性所呈现的致毒特征与离子种类及其毒性强度匹配情形密切相关。  相似文献   

8.
Benzo[a]pyrene (BaP), a procarcinogenic polycyclic aromatic hydrocarbon (PAH), is bioactivated to BaP diol-epoxides (BPDEs) that can form adducts with DNA and blood proteins. We report here for the first time the in vivo formation of adducts between BPDE and plasma albumin (Alb) from two fish species experimentally exposed to BaP. Brook trout (Salvelinus fontinalis) received either a single i.p. dose (10 mg/kg) or two separate i.p. doses (25 mg/kg; 7 days apart) of BaP, and blood was collected 2 (single exposure) or 3 (multiple exposure) days post-treatment. Arctic charr (Salvelinus alpinus) received 10 i.p. doses (3 mg/kg; a single dose every 6 days), and blood was collected 2 days after the second, sixth, and 10th injections. BPDE-Alb adducts were measured by an improved HPLC/fluorescence method developed to detect and quantify BaP-tetrols released after acid hydrolysis of adducted Alb. HPLC/fluorescence chromatograms of Alb from BaP-treated fish revealed only BaP-tetrol I-1, thus indicating the formation of adducts exclusively via the (+)-anti-BPDE metabolite. Levels of (+)-anti-BPDE-Alb adduct ranged from 0.68 to 19.6 ng of tetrol I-1 per gram of Alb. Notably, adduct level was not related to BaP dose and there was no accumulation of adducts with repeated exposure, which may indicate a very short half-life (< 2 days) of plasma Alb in fish. The data suggest that BPDE-Alb adducts in fish could be useful as a non-destructive biomarker of recent exposure to bioactivated BaP.  相似文献   

9.
《Oceanologica Acta》1998,21(5):677-694
Microphytobenthic biomass was estimated in the Bay of Brest (1994) and the western English Channel (Trezen Vraz, 1993) using spectrophotometry. Best results (42 % difference) were obtained with an instantaneous extraction procedure at room temperature, compared with the cold extraction procedure. Chlorophyll biomass in sediment was higher in the western English Channel (65–215 mg Chl a m−2) than in the Bay of Brest (10–113 mg Chl a m−2), in contrast to total pigment biomass (Chl a + pheo a : 88–254 mg m−2 at Trezen Vraz vs. 131–934 mg m−2 in the Bay of Brest). This study emphasized decreasing pigment biomass from the estuary to the open sea. Low benthic pigment biomass in the Bay, compared to eutrophic ecosystems, agrees with previous studies on the pelagic system, suggesting that there is no eutrophication in the Bay of Brest. Microphytobenthic blooms were strongly correlated with environmental factors, such as river floods, light intensity, water temperature and the spring/neap tidal cycle. Turbidity and light could be limiting factors at Roscanvel, i.e. the deepest site facing gyre circulation. The latter would favour sedimentation of silt particles at the sediment-water interface. Microphytobenthos population dynamics would be also dependent on the spring/neap tidal cycle, since maximum chlorophyll biomass occurred at neap tides at all three sites in the Bay of Brest, in contrast to the western English Channel. Lower temporal variations of pigment biomass in sediment were observed in the Channel, compared with the Bay of Brest; maximum chlorophyll biomass in sediment was found to occur three to four weeks after the phytoplankton blooms.  相似文献   

10.
不同剂型和剂量的维生素C对幼刺参生长的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
在水温11.0~14.0℃条件下,将平均体质量2.29 g的幼刺参(Apostichopus japonicus)随机放入39个容积50 L塑料水槽中,投喂以玉米蛋白为蛋白源,分别添加0、500、1 000、2 000和4 000 mg/kg V_C-2-三聚磷酸酯(L-ascorby1-2-polyphosphate, LAPP)、V_C-棕榈酸酯(L-ascorby1 palmitate, LAP)和V_C -磷酸酯镁(L-ascorby1-2-monophosphate-magnesium, APM)的13种饲料.90 d的饲养情况表明,摄食添加V_C饲料的刺参的生长、蛋白质效率均显著高于摄食未添加V_C的幼参(P<0.05).摄食添加LAPP饲料幼参的特殊生长率最高(0.21%/d),添加LAP(0.17%/d)的次之,添加APM(0.15%/d)的最低,分别比对照组(0.12%/d)高75.00%、41.67%和25.00%.摄食添加LAPP饲料幼参的平均蛋白质效率最高(12.57%),摄食添加LAP饲料的(7.76%)次之,摄食添加APM(6.86%)的最低,分别比对照组(5.52%)高127.72%、40.58%和24.28%.在3种剂型V_C组中,饲料系数由低到高依次为:LAPP<LAP<APM.饲料中LAPP、APM和LAP的添加量为2 000~2 500 mg/kg、1 000~1 500 mg/kg和2 000~3 125 mg/kg时,幼刺参对饲料蛋白的表观消化率最高,生长最快,饲料系数最低.  相似文献   

11.
温度对墨西哥湾扇贝耗氧率及排泄率的影响   总被引:63,自引:2,他引:61  
于1996年12月至1997年1月在实验室内研究了温度对墨西哥湾扇贝(Argopecten irradians concentricus)的耗氧率和排泄(NH4-N)率的影响,实验在投饵后6h,静水(盐度32)条件下进行,溶氧量和氨氮量分别采用Winkler滴定法和次溴酸盐氧化法测定.实验结果表明,在实验温度(10~31℃)条件下,不同规格(壳高1.6~4.8cm,软体部干重0.0342~0.6908g)的墨西哥湾扇贝耗氧率的总平均值为2.35mg/(g·h).排泄率总平均值为350.89μg/(g·h).墨西哥湾扇见的耗氧量和排氧量都与扇贝体重呈明显的幂函数关系.在10~28℃范围内,不同规格的扇贝耗氧率都随温度的升高而增加;当水温继续升高到31℃时,耗氧率反而下降.在实验温度(10~31℃)条件下,扇贝的排泄率随着温度的升高而增加,温度对墨西哥湾扇贝的耗氧率和排泄率的影响都可用指数方程表示.本实验证实,高温(31℃)将进一步提高墨西哥湾扇贝蛋白质的代谢水平.耗氧量(O)和排氨量(N)与温度(t)、扇贝软体部干重(W)二元线性回归方程分别为:O=-587.804+36.787t+1697.864W;N=-92.344 9+4.534 1t+276.781 8W.复相关系数r分别为0.880 6和0.8035 ; F检验表明,两个回归方程均极显著(F>F0.01).  相似文献   

12.
半滑舌鳎封闭式循环水养殖系统的设计与应用   总被引:3,自引:0,他引:3  
设计了生物承载量为45t、养殖密度为45kg/m3的半滑舌鳎封闭式循环水养殖系统,对养殖半滑舌鳎8个月的水处理效果进行测定和分析。循环水系统设计主要参数为:养殖半滑舌鳎3万余尾,补水量53m3/d,补水率约5%,供氧量7.4kg/h,循环量1 281m3/h,循环次数为20次/d,生物过滤器有效体积为106m3。经系统处理后,养殖池内水温为18~21℃,pH=7.0~8.0,DO≥6.6mg/L,养殖池进水氨氮0.017~0.178mg/L,亚硝酸氮0.012~0.064mg/L,细菌0~220个/mL,弧菌0~30个/mL。系统的水处理效果达到了养殖鱼对水质的要求。试验期间,共投喂饵料34 511kg,饵料系数1.1。试验结束时,生产半滑舌鳎成鱼41 469kg,与传统养殖模式相比,提高了养殖产量。本系统在水产养殖生产中具有一定的借鉴和推广使用价值。  相似文献   

13.
中国对虾家系幼体对氨氮和pH值的耐受性比较   总被引:6,自引:0,他引:6  
采用人工授精技术建立中国对虾家系,对建立的20个家系幼体通过急性毒性试验进行抗氨氮和pH值性状的比较.结果表明:不同试验时间中国对虾家系对氨氮和pH值的耐受性差异极显著(P<0.01)和显著(P<0.05),24,48和72 h对氨氮耐受性的平均半数致死值分别为62.15,30.31和15.60 mg/L,对pH值耐受性的平均半数致死值分别为9.99,9.41和9.12.以平均LD50值为评价指标,综合24,48和72 h各家系对氨氮和pH的耐受性,最终筛选出对氨氮耐受性最强的家系8个,对pH值耐受性最强的家系10个,对氨氮和pH值耐受性均较强的家系7个,为构建中国对虾抗逆基础群体,开展中国对虾抗逆新品系的选育工作提供了基础.  相似文献   

14.
Using a suitable solvent for extracting pigments from sediment for high performance liquid chro-matography (HPLC) analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass, as well as community composition. Five methodolog-ical factors (sample dehydration, extraction solvent, extraction duration, number of extractions, and ratio of solvent volume: sample weight) were studied using an L9 (34) orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary (LDE), using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L9 (34) or-thogonal design experiments and showed that the extraction solvent was the most important, with extraction duration the second most important, and numbers of extraction and ratio of solvent vol-ume: sample weight was the least important. The mixed solvent treatment comprised of acetone, methanol and water (80:15:5, by volume) was best for polar pigment extraction, with 100% acetone better for apolar pigments. For most pigments employed in this study (i.e., peridinin, fucoxanthin, alloxanthin, diatoxanthin, zeaxanthin, pheophytin-a and β-carotene), 3 h was found to be enough time for extraction from these deltaic sediments. However, for chlorophyll-a, the most important pigment used for estimating algal biomass, 12 h was needed. A small amount of solvent (3 ml) with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately, no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study, taking into consideration the properties of sediments and pigments in question.  相似文献   

15.
5种海水养殖鱼类幼鱼的耗氧率及窒息点   总被引:1,自引:0,他引:1  
为鱼类苗种运输和养殖过程中溶解氧的科学调控提供理论依据,采用密闭式呼吸实验法探究了20、25和30 ℃水温下豹纹鳃棘鲈Plectropomus leopardus、驼背鲈Cromileptes altivelis、棕点石斑鱼Epinephelus fuscoguttatus、赤点石斑鱼Epinephelus akaara和珍珠龙胆石斑鱼5种海水养殖鱼类幼鱼(体重范围为53.6~84.5 g)的耗氧率和窒息点。结果表明:在盐度为30的条件下,5种海水养殖鱼类幼鱼的耗氧率和窒息点均随水温的升高而升高。同水温下的耗氧率,豹纹鳃棘鲈为最高, 20、25和30 ℃水温下分别为0.15、0.21和0.31 mg/(g·h);珍珠龙胆石斑鱼为最低,20、25和30 ℃水温下分别为0.08、0.15和0.16 mg/(g·h)。同水温下窒息点,驼背鲈为最高, 20、25和30 ℃水温下分别为1.00、1.12和1.21 mg/L ;珍珠龙胆石斑鱼为最低, 20、25和30 ℃水温下分别为0.19、0.24和0.25 mg/L。  相似文献   

16.
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。  相似文献   

17.
The dynamics of phytoplankton diversity constitute crucial data in environmental monitoring, food-web studies and ecosystem modeling. Proper assessment of phytoplankton community composition requires large investments in offshore sampling and taxonomic competence because these communities can change fundamentally on a weekly scale. Cheap and high-frequent offshore phytoplankton sampling can be achieved by using ships-of-opportunity, and in the present study we used the Alg@line facilities onboard a passenger ferry during its regular route between Finland and Sweden in the northern Baltic Sea. The first aim was to test if pigment analysis, as a cheaper alternative to cell counts, can be used to detect environment-correlated variation in phytoplankton communities. It has been shown that spatial variation (salinity differences) and variation throughout one annual cycle (changes in temperature and nutrients) were strongly reflected by pigment composition. The second aim was to test if pigment analyses and cell counts detect environment-correlated variation in phytoplankton communities equally well. It has been shown that spatial and seasonal variations were reflected by pigment composition while cell counts reflected seasonal variation only. This suggests that the pigment analyses detected aspects of the phytoplankton that were neglected or misinterpreted by cell counts. It is advocated that available resources of long-term studies, such as environmental monitoring, can be used more efficiently by utilizing the high ecological resolution of pigment composition in combination with high-frequent ships-of-opportunity sampling. To assess heterotrophic and/or toxic species, such programs could also include sampling for cell counts in a complementary manner, with actually performing counts only for crucial samples (e.g. between large community changes) as indicated by multivariate statistical analysis of pigment composition. Some aspects of analyzing phytoplankton data with multivariate statistics are also discussed.  相似文献   

18.
用臭氧处理海水对鱼虾的急性毒性效应研究   总被引:9,自引:2,他引:9  
姜国良  刘云  杨栋  吕艳 《海洋科学》2001,25(3):11-13
本实验检测了不同浓度臭氧残留对中国对虾(Penaeus chinensis)、牙鲆(Paralichthys oilvaceus)存活率的影响。结果表明,对虾的耐受力要比牙鲆鱼强,中国对虾在臭氧浓度≥1.0mg/L时,可存活至少48h,而芽鲆在此浓度下3h后,即出现鳃部充血肿胀、呼吸频率加快等不适应现象,48h LC50为0.13mg/L。如果能正确控制臭氧的残留量,利用臭氧净化养殖用水是一个不容质疑的水质净化的好方法。  相似文献   

19.
以分离自南极海洋的寡营养细菌所产的褐色素为试验材料,进行了该色素的提取和稳定性分析。结果表明,色素粗品至少含有3种以上不同的褐色素,该褐色素易溶于水和甲醇;最大吸收波长为214nm;在pH≥4.0、热、光照(自然光与紫外线)下都能表现出良好的稳定性;抗H2O2、HNO3氧化能力强,NaClO对其破坏较大;Na2SO3、抗坏血酸对其有护色作用;Fe3+、Fe2+和Pb2+则有一定的破坏作用,Mg2+对该色素有护色作用,其它金属离子影响不大。试验表明,寡营养细菌褐色素在稳定性上呈现出一定优势,具有作为一种天然色素资源的开发和应用价值。  相似文献   

20.
In order to investigate the mechanism by which o,p'-DDT disrupts endocrine functioning of Nile tilapia in vivo, the estrogenicity of o,p'-DDT was investigated in conjunction with 17beta-estradiol (E2) and tamoxifen. Mature, male tilapia were treated intraperitoneally with o,p'-DDT (60 mg/kg, one dose) or E2 (5 mg/kg, four doses) in the presence or absence of tamoxifen (5 mg/kg, six doses) for 12 days and then plasma vitellogenin (Vtg) (measured as alkaline-labile phosphorous), E2, and testosterone (T) were measured. Vtg levels were increased dramatically by E2 (1,744 +/- 171 microg/ml) and moderately by o,p'-DDT (82 +/- 15 microg/ml) compared with controls (23 +/- 3.5 microg/ml). Tamoxifen alone had no effect on Vtg production, but inhibited both E2 and o,p'-DDT stimulated vitellogenesis. T levels were reduced with E2 administration (1,688 +/- 383 pg/ml) and declined further with the combined treatment of E2 and tamoxifen (281 +/- 70 pg/ml), compared with controls (6,558 +/- 1,438 pg/ml). Tamoxifen or o,p'-DDT alone did not affect T levels, but their combined treatment did (2,069 +/- 647 pg/ml). The results of this study suggest that o,p'-DDT is weakly estrogenic in male tilapia, and that this activity may be mediated through the estrogen receptor.  相似文献   

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