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1.
以赤潮异弯藻为研究对象,设置氮、磷浓度分别为16μmol/L∶16μmol/L、64μmol/L∶16μmol/L、256μmol/L∶16μmol/L、256μmol/L∶4μmol/L和256μmol/L∶2μmol/L,以2,2′,4,4′-四溴联苯醚为多溴联苯醚的代表,研究氮磷比对赤潮异弯藻不同生长时期富集多溴联苯醚的影响,并分析赤潮异弯藻对2,2′,4′4-四溴联苯醚的富集与其总脂和总碳水化合物含量的关系。研究结果表明,在赤潮异弯藻生长的延缓期,氮磷比对单位细胞的多溴联苯醚富集量没有影响,在对数期和稳定期,除256μmol/L∶16μmol/L条件下,富集量均明显增加,其中256μmol/L∶2μmol/L条件下富集量最高,在稳定期可达1.5fg/个。由于氮磷比导致赤潮异弯藻的总脂等生化成分含量发生变化,且赤潮异弯藻的富集量与其细胞总脂含量呈显著正相关,氮磷比影响了赤潮异弯藻对多溴联苯醚的富集。 相似文献
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《畜禽业》2021,(8)
目的建立动物源性食品(猪肉、猪肝、禽肉)中喹乙醇代谢物3-甲基喹噁啉-2-羧酸(MQCA)高效液相色谱-串联质谱法。方法样品通过偏磷酸水解提取MQCA,MAX固相萃取柱净化。采用0.1%甲酸溶液和甲醇溶液作为流动相进行梯度洗脱,质谱(ESI+)采用多离子检测模式(MRM)对MQCA的定量离子和定性离子进行监测。结果该方法10 min完成目标化合物的分析,MQCA在0.5～2μg/kg浓度范围内呈良好的线性关系,MQCA在0.5μg/kg、1μg/kg和2μg/kg添加水平的回收率为75.4%～105%,相对标准偏差小于7.96%(n=6),方法检出低限为0.1μg/kg。结论该方法前处理耗时短、灵敏度高、回收率高,适用于动物源性食品(猪肉、猪肝、禽肉)中喹乙醇代谢物3-甲基喹噁啉-2-羧酸(MQCA)的残留测定。 相似文献
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建立了以高效液相色谱-串联质谱法同时检测养殖池塘沉积物中喹诺酮类、四环素类、磺胺类16种抗生素的分析方法。沉积物样品经提取液[磷酸盐缓冲液(pH=3)∶乙腈=1∶1]提取后,以MAX-HLB串联小柱净化富集,在HPLC/MS/MS多反应监测模式下进行定性及定量分析,当目标化合物添加浓度为10μg/kg和100μg/kg时,沉积物中喹诺酮类、四环素类、磺胺类的加标回收率分别为67.6%~107.1%,63.8%~118.7%,67.1%~116.4%,相对标准偏差在5.1~12.9。以3倍信噪比估算出喹诺酮类、四环素类、磺胺类的检出限分别为0.14~0.64、1.8~3.9、0.18~0.42μg/kg。应用此方法检测21口池塘的43个沉积物样品,结果表明,该方法操作简便,重现性好,可用于池塘沉积物中抗生素的检测。 相似文献
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《中国渔业质量与标准》2017,(4)
[目的]建立一种使用液相色谱-串联质谱联用仪快速准确检测池塘沉积物中痕量氯霉素残留的方法,为水产品中氯霉素污染来源的排查提供技术支持。[方法]底泥经润湿后,经乙酸乙酯水饱和溶液提取,Sep-Pa K C_(18)固相萃取柱净化,Shim-Pack XR-ODS色谱柱分离,采用甲醇和水为流动相,并用梯度洗脱对待测物进行分离,以氘代氯霉素(氯霉素-D5)为内标,采用负离子扫描,多反应监测模式(MRM),定性离子对m/z为321→152.0,256.8,定量离子对m/z为321→152.0。[结果]氯霉素类药物在0.5~10.0 ng/m L范围内线性良好,相关系数均大于0.99,本方法的检出限为0.1μg/kg,定量限为0.3μg/kg。3个加标水平(0.5、1.0和5.0μg/kg)的平均回收率为90.1%~96.6%,相对标准偏差为2.4%~7.0%。[结论]实验结果符合氯霉素药物残留检测的相关法规要求,适用于淡水池塘沉积物中氯霉素残留的定性定量检测。 相似文献
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本文建立了一种水产品中4种三唑类农药残留的固相萃取-气相色谱检测方法,4种三唑类农药包括三唑酮、三唑醇、环丙唑醇和联苯三唑醇。采用乙腈提取样品,石墨化碳黑-弗罗里硅土复合柱净化,丙酮-正己烷(1∶9,V/V)溶液洗脱,以及利用气相色谱法测定和外标法定量。研究显示,三唑酮在1.25~125.00 ng/m L,三唑醇、环丙唑醇和联苯三唑醇在25~2 500 ng/m L范围内响应值与质量浓度的线性关系良好,相关系数为0.999 7~0.999 8。当添加浓度分别为三唑酮0.4~8.0μg/kg,三唑醇、环丙唑醇和联苯三唑醇8~160μg/kg时,鳗鲡、日本对虾、鲍鱼和龙须菜加标样品的日内和日间平均回收率为78.8%~95.0%,相对标准偏差为1.48%~11.4%;三唑醇、环丙唑醇和联苯三唑醇检出限均为4.0μg/kg,最低定量限均为8.0μg/kg;三唑酮的检出限为0.2μg/kg,最低定量限为0.4μg/kg。研究结果表明,本文建立的固相萃取-气相色谱检测方法可以有效检测出水产品中4种三唑类农药的残留。 相似文献
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建立高效液相色谱-串联质谱同时定量检测双壳类动物中六溴环十二烷(HBCD)、四溴双酚A(TBBPA)方法。样品经正己烷和二氯甲烷混合液(1∶1,V/V)提取,浓硫酸除脂,硅胶固相萃取柱净化,Thermo Hypersil Gold C_(18)色谱柱分离,水和甲醇-乙腈梯度洗脱,电喷雾负离子模式下以多反应监测方式检测,内标法定量分析。结果表明,六溴环十二烷(α,β,γ-HBCD)和四溴双酚A在0.5~100 ng/mL范围内线性关系良好(R20.995),方法定量限(S/N≥10)为0.05μg/kg。在0.05~0.5μg/kg添加水平内,平均回收率为70.5%~92.4%,日内相对标准偏差(RSD)为3.4%~9.1%,日间RSD为6.3%~10.2%。 相似文献
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《中国渔业质量与标准》2016,(3)
建立了同时测定海洋沉积物中16种除草剂的固相萃取-气相色谱质谱检测方法。样品经乙酸乙酯-二氯甲烷(3∶2;V/V)混合溶液提取,浓缩,甲醇复溶,加入纯水稀释,过HLB固相萃取柱富集、净化,洗脱液氮吹浓缩,乙酸乙酯定容上机,用气相色谱质谱仪(GC/MS)选择离子监测模式定性定量分析,外标法定量。方法中二甲戊乐灵、草净津检出限为1.5μg/kg,其余14种除草剂检出限均为0.8μg/kg;二甲戊乐灵、草净津线性范围为4.0~200.0μg/L,其余14种除草剂线性范围均为2.0~100.0μg/L;方法加标回收率为74.2%~97.3%,相对标准偏差为5.83%~11.6%。该方法灵敏准确,适用于海洋沉积物中16种除草剂的定性定量检测,对加强渔业生态环境保护提供技术支持。 相似文献
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将海水小球藻培养在不同pH(8.66、8.44、8.19、7.93)下、不同含量(0、1.52、3.04、6.08、12.16、24.32μg/g)五溴联苯醚BDE-85中，在指数生长期时测定海水小球藻的比生长速率、净光合放氧速率、暗呼吸速率、叶绿素荧光参数以及超氧化物歧化酶和过氧化氢酶活性等参数，探讨不同pH条件下海水小球藻对BDE-85致毒胁迫的生理响应。试验结果表明，低pH条件下经过中、低含量BDE-85处理的海水小球藻的比生长速率呈增加趋势，其中6.08、12.16μg/g试验组较对照组分别增长了6.33%、7.39%;6.08μg/g试验组在低pH条件下净光合放氧速率比对照组高出18.43%,而24.32μg/g试验组则比对照组低39.98%;同时过氧化氢酶和超氧化物歧化酶活性增强，表明海水小球藻的抗氧化作用增强，出现了应激活性，但高含量(24.32μg/g试验组)的BDE-85处理下增强作用不明显。综上，低pH条件可以促进海水小球藻的生长，也可以缓解中、低含量的五溴联苯醚BDE-85的毒害作用，但当BDE-85含量过高时，其缓解效果受到抑制，并且在高含量的BDE-85处理下... 相似文献
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利用气相色谱-质谱联用技术测定紫菜中六六六、滴滴涕和扑草净的残留量。试样用乙腈提取,经石墨化炭黑/氨基复合柱净化,采用气相色谱-电子轰击源质谱测定,检测模式采用选择离子监测(SIM),外标法定量。研究结果显示,六六六方法定量限为5.0μg/kg,滴滴涕为2.5–5.0μg/kg,扑草净为2.5μg/kg。各组分加标回收率在78.5%–112.0%之间,相对标准偏差在3.6%–10.3%之间。结果表明,该方法简便、快速,其准确度和精密度能够满足紫菜中六六六、滴滴涕和扑草净同时检测的要求。 相似文献
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《中国渔业质量与标准》2017,(5)
[目的]建立了水产品中辛硫磷、倍硫磷和蝇毒磷3种有机磷农药的检测方法。[方法]样品经酸化乙腈提取,PSA吸附剂分散固相萃取净化,超高效液相色谱-串联质谱在多反应离子监测模式下检测,基质匹配外标法定量。结果加标浓度在10~100μg/kg范围内,线性相关系数(R)大于0.99。3种有机磷农药的平均回收率范围为65.8%~101.0%,RSD范围为11.4%~16.0%。本方法检出限为10μg/kg,定量限为20μg/kg。[结论]该方法可用于水产品中辛硫磷、倍硫磷和蝇毒磷等3种有机磷农药残留的同时测定。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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