湛江市售海产品中镉砷铬污染状况评价

为研究海产品中的重金属污染状况和海产品的安全水平，采用微波消解法预处理样品，电感耦合等离子体发射光谱法测定海产品中Cd、As、Cr的含量，并采用单因子污染指数法评价重金属的污染程度。结果表明：海产品的合格率达89％，鲍鱼中的Cd超标，海产品中重金属污染主要表现为Cd、As的污染；鲍鱼属于三级产品．虾和沙螺都属于一级产品。     

湛江市场食用鱼类和甲壳类重金属的检测与评价

通过硝酸一过氧化氢作消解液微波消解处理样品，采用ICP-AES法测定湛江海域鱼类和甲壳类样品中Zn、Cd、As、Cr、Cu等重金属含量，并根据相应标准对重金属含量进行评价及食用安全评估。调查结果显示，重金属在不同种类海产品中的分布情况有所不同，被调查的种类海产品中各种重金属（除鱼类中的Cd）含量均低于“海洋生物污染评价标准”，鱼类和甲壳类的Cd含量则高于“人体消费卫生标准”。对消费者的健康构成了严重的威胁，应该引起重视。     

IPC法测定补锌后仔猪血清中锌、铜和铁含量及其变化分析

将40头仔猪分为5组,并在仔猪日粮中补充80、240、1000、3000、5000mg/kg锌,研究日粮补锌对仔猪血清锌、铜、铁的影响;血清样品采用湿法消解,利用ICP法分析测定仔猪补锌后血清中锌、铜和铁含量。研究结果显示:ICP法简便、快速、准确度高,适于大批量的样品分析;仔猪补锌后血清锌含量随日粮增加而升高(P<0.05),高锌1000、3000和5000mg/kg对血清铜、铁含量有显著抑制作用(P<0.05)。     

几种海洋药用动物中重金属元素的含量分析

对我国几种传统海洋药用动物中重金属元素的含量进行了测定,并对同产地的陆生药用动物蛤蚧进行比较研究,其中Hg和As利用原子荧光光度计测定,Pb、Cd、Cu、Fe、Mn、Zn利用原子吸收光度计测定,样品采用微波消解仪消解。结果表明:海钱、海蛇、海马、海星的镉含量较高,海燕、海马、海星的铅含量较高,除个别样品微量元素未检出外,样品中Fe、Mn、Zn的含量相对较高。最后对金属元素含量较高的原因及对所含微量元素的食用安全性和营养学评价进行了探讨。     

正交实验优化微波消解海洋沉积物重金属镉测定的条件

为优化微波消解海洋沉积物重金属镉测定的实验条件,设计三因素(温度、保持时间、微波功率)三水平的正交实验,微波消解海洋沉积物成分分析标准物质,用原子吸收分光光度计测定消解液镉含量,计算回收率,数据常用SPSS18.0软件进行分析。结果显示,海洋沉积物微波消解最佳实验条件组合为180℃,5min,1200W,该条件下海洋沉积物微波消解镉测定回收率为96.5%。     

原子吸收测定鱼体中的铜、铅、镉——干灰化与湿消解法前处理样品比较

本文报道了原子吸收测定鱼体中的铜、铅、镉－干灰化法与湿消解法前处理样品测定数据的比较。结果表明：湿消解法不但防止了样品挥发损失，而且是准确度和精确密度较高的分析方法，同时多次加标平均回收率在99．3％－102．31％之间，均高于干灰化法（63．75－66．25％）。比较分析结果，令人较为满意，适用于批量样品测定。     

高效液相法测药品中甲硝唑的含量

采用高效液相色谱法(HPLC)测定甲硝唑片的含量,本法具有简便、快速、准确等优点,可用于甲硝唑片含量的测定。     

水产品和养殖环境中重金属的微波消解——原子吸收检测技术

本文介绍了目前最常用的水产品和养殖环境中铜、镉、铅、锌、铬和镍等重金属含量的微波消解一原子吸收检测技术。采用微波消解一原子吸收检测技术微波消解法是利用微波的穿透性和激活反应能力加热密闭容器内的试剂和样品可使制样容器内压力增加，反应温度提高，大大缩短样品制备的时间。并且可控制反应条件．使制样精度更高。且由于采用特殊的防腐防爆材料和减压设施，安全性较好。该方法用于水产品和养殖环境样品中铜、镉、铅、锌、铬和镍等重金属的检测，快速、准确、安全。     

有关测定鱼肝油制剂Vit．A含量的几个问题

Vit．A是鱼肝油制剂的主要成分。准确测定其含量有着重要意义。自1946年R．A．Morton和A．L．Stubbs首先提出用三点校正法测定Vit．A含量后，至今仍被英、美、日等许多国家采用。中国药典也规定此法为法定方法。之后，用紫外分光光度计三点校正法测定Vit．A含量，逐步取代了经典的比色法。     

大连沿海虾夷扇贝体内重金属含量研究与质量评价

用微波消解对大连沿海虾夷扇贝样品进行处理,电感耦合等离子体质谱法测定虾夷扇贝不同组织中重金属Pd、Cd、Hg、Cr、Cu、Zn的含量,同时对重金属含量进行质量评价。试验结果表明,Pd、Cd、Hg、Cr、Cu、Zn在不同海域虾夷扇贝中的含量相差较大,6种重金属的平均含量分别为0.488、2.924、0.047、1.394、2.152、36.08mg/kg,即ZnCdCuCrPbHg。虾夷扇贝不同组织蓄积重金属具有明显的差异性,闭壳肌中重金属Cd、Cu的含量显著低于其他组织,Zn的含量却高于内脏团,不同组织对Cr的蓄积程度差异较小。调查发现,虾夷扇贝中重金属Cd的含量较高,尤其内脏部分远超过我国无公害水产品中有毒有害物质限量,建议食用虾夷扇贝时去除内脏团。     

Application of the Tweedie distribution to zero-catch data in CPUE analysis

We focus on the zero-catch problem of CPUE (catch per unit effort) standardization. Because the traditional CPUE model with a log-normal error structure cannot be applied in this case, three methods have often been utilized as follows:

(1) Ad hoc method adds a small constant value to all response variables.

(2) Catch model with a Poisson or negative-binomial (NB) error structure.

(3) Delta-type two-step method such as the delta-normal model (after estimating the ratio of zero-catch using a logit or probit model, a model such as CPUE log-normal or Catch-Poisson is applied to CPUE without zero-data).

However, there are some statistical problems with each of these methods.In this paper, we carried out the CPUE standardization mainly using the Tweedie distribution model based on the actual by-catch data (silky shark, Carcharhimus falciformis, in the North Pacific Ocean caught by Japanese training vessels) including many observations with zero-catch (>2/3rd) and tuna fishery data as a target (yellowfin tuna, Thunnus albacares, in the Indian Ocean caught by Japanese commercial vessels) where the ratio of zero-catch is not so high (<1/3rd). The Tweedie model is an extension of compound Poisson model derived from the stochastic process where the weight of the counted objects (i.e., number of fish) has a gamma distribution and has an advantage of handling the zero-catch data in a unified way.We also compared four candidate models, the Catch-NB model, ad hoc method, Delta-lognormal model (delta-type two-step method) and Tweedie distribution, through CPUE analyses of actual fishery data in terms of the statistical performance. Square error and Pearson's correlation coefficient were calculated based on the observed CPUE and the corresponding predicted CPUE using the n-fold cross-validation.As a result, the differences in the trend of CPUE between years and model performance between the ad hoc method and Tweedie model were found to be not so large in the example of yellowfin tuna (target species). However, the statistical performance of Tweedie distribution is rather better than Delta-lognormal model, the Catch-NB distribution and ad hoc method in the example of silky shark (by-catch species). Standardized CPUE year trend of ad hoc method was found to be quite different from that of the Tweedie distribution and other two models. Model performance of the Tweedie distribution is good judging from the 5-fold cross-validation using the fishery data if including many zero-catch data such as by-catch species.     

Tank spawning of grass carp

Induced spawning of grass carp in indoor tanks without hand stripping of gametes is described. Circular tanks (1.83 m diameter) with biofiltration units were utilized for conditioning and spawning. This method was found to be successful and has several advantages over the dry-fertilization method: (1) preliminary ripening and spawning is conducted in small systems where the environment is controlled; (2) manpower requirements are reduced; (3) handling of brood fish is reduced, thereby minimizing mortalities; and (4) spawning occurs when the fish is physiologically ready, insuring good egg quality.     

Effect of salinity on the biosynthesis of n-3 long-chain polyunsaturated fatty acids in silverside Chirostoma estor

The genus Chirostoma (silversides) belongs to the family Atherinopsidae, which contains around 150 species, most of which are marine. However, Mexican silverside (Chirostoma estor) is one of the few representatives of freshwater atherinopsids and is only found in some lakes of the Mexican Central Plateau. However, studies have shown that C. estor has improved survival, growth, and development when cultured in water conditions with increased salinity. In addition, C. estor displays an unusual fatty acid composition for a freshwater fish with high docosahexaenoic acid (DHA)/ eicosapentaenoic acid (EPA) ratios. Freshwater and marine fish species display very different essential fatty acid metabolism and requirements, and so the present study investigated long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis to determine the capacity of C. estor for endogenous production of EPA and DHA, and the effect that salinity has on these pathways. Briefly, C. estor were maintained at three salinities (0, 5, and 15 ppt), and the metabolism of 1?C-labeled 18:3n-3 was determined in isolated hepatocyte and enterocyte cells. The results showed that C. estor has the capacity for endogenous biosynthesis of LC-PUFA from 18-carbon fatty acid precursors, but that the pathway was essentially only active in saline conditions with virtually no activity in cells isolated from fish grown in freshwater. The activity of the LC-PUFA biosynthesis pathway was also higher in cells isolated from fish at 15 ppt compared with fish at 5 ppt. The activity was around fivefold higher in hepatocytes compared with enterocytes; although the majority of 18:3n-3 was converted to 18:4n-3 and 20:4n-3 in hepatocytes, the proportions of 18:3n-3 converted to EPA and DHA were higher in enterocytes. The data were consistent with the hypothesis that conversion of EPA to DHA could contribute, at least in part, to the generally high DHA/EPA ratios observed in the tissue lipids of C. estor.     

两种典型渔法金枪鱼围网网具的性能差异

摘要：为了量化分析自由鱼群渔法和漂流物渔法的网具性能差异,本文根据2011-2014年金枪鱼围网海上调查数据,采用Bootstrap和GAM方法进行分析。结果显示：（1）漂流物渔法时,网具的最大沉降深度（195.20~219.36m）约为自由鱼群渔法时最大沉降深度 （205.83~219.04m）的94.8%;网具的平均沉降速度（0.152~0.176m/s）约为自由鱼群渔法时平均沉降速度（0.180~0.193m/s）的84.4%~91.2%。（2）捕捞自由鱼群时,影响沉降速度主要因子为10m水层流速（V10）,60m水层流速（V60）和跑纲长度（L1）。（3）捕捞漂流物随附群时,影响沉降速度主要因子为60m水层流速（V60）,括纲长度（L）和放网速度（V0）。（4）GAM模型结果显示,漂流物渔法时,预测的沉降速度（0.155~0.175m/s）达到海上实测沉降速度的99.4%;自由鱼群渔法时,预测的沉降速度（0.182~0.190m/s）达到海上实测沉降速度的98.4%。本研究结果可为海上作业时,判别海况条件和控制渔法操作提供一定参考。     

中华绒螯蟹“颤抖病”病毒提纯方法的比较

以患“颤抖病”中华绒螯蟹组织浓缩液为材料,比较了差速离心结合PEG盐析法(方法1)、葡聚糖柱层析法(方法2)和蔗糖密度梯度超速离心法(方法3)三种方法分离提纯病毒的效果,对提纯病毒进行紫外吸收测定及电镜检查等。结果表明:方法3是用于分子生物学等深入研究该病的比较理想的提纯方法;而方法1所得病毒浓缩液虽纯度不及方法3,但基本可以满足一般研究的要求,且对仪器及技术的要求相对较低;方法2则介乎方法1与方法3之间。故可根据具体需求和实验室条件选择适合的中华绒螯蟹“颤抖病”病毒提纯方法。     

6—DMAP诱导太平洋牡蛎三倍体——抑制受精卵第二极体释放↑（*）

于１９９６～１９９７年,用６－ＤＭＡＰ抑制太平洋牡蛎受精卵第二极体的释放,诱导产生三倍体,最高诱导率为９３．８％。该实验组胚胎孵化率为８１．０％,Ｄ形幼虫畸形率为１７．６％。实验选用Ｌ９（３４）设计,进行三因素三水平的正交试验：６－ＤＭＡＰ浓度,设３００、４５０和６００μｍｏｌ／Ｌ等三水平;诱导时机（观察静止状态的受精卵,以受精卵出现第一极体的百分率指示）,设１０％、３０％和５０％等三水平;诱导持续时间,设１０、１５和２０ｍｉｎ等三水平,试验设三次重复。解剖法获取精卵,人工授精。染色体倍性检查采用染色体计数法。根据正交试验直观分析结果,得出诱导太平洋牡蛎三倍体各因素的最优水平组合：当３０％受精卵出现第一极体时,将受精卵浸泡在含６－ＤＭＡＰ４５０μｍｏｌ／Ｌ的海水中１０ｍｉｎ;三因素的主次顺序：６－ＤＭＡＰ浓度→诱导时机→诱导持续时间。６－ＤＭＡＰ的浓度和诱导时机对三倍体诱导率的影响显著;但诱导持续时间影响不显著。部分试验组得到４．２％～１３．６％的四倍体和１０％左右的非整倍体,这种情况可能与受精不同步抑制第一极体释放而导致的染色体多极分离有关。     

水产品中拟除虫菊酯类农药残留检测方法的研究

建立了水产品中氯氰菊酯、甲氰菊酯、氰戊菊酯和溴氰菊酯等拟除虫菊酯类农药残留的提取、净化以及毛细管气相色谱的测定方法。选择40mL正己烷：丙酮（V／V,2：1）混合溶液作为提取液,经冷冻去脂,柱层析净化过程中选用3g中性氧化铝作为净化填料,30mL正己烷：丙酮（V／V,4：1）混合溶液进行洗脱,然后用气相色谱法测定,外标法定量。实验结果表明,在10～200ng／mL线性范围内线性良好,相关系数在0．9993～0．9998。标准品添加量在10～66μg／kg范围内,罗非鱼样品加标实验的回收率在76．9～90．3％,相对标准偏差在1．25—4．66％,样品中氯氰菊酯、甲氰菊酯、氰戊菊酯、溴氰菊酯残留量检测方法的检出限为10μg／kg。另外采用鳗鱼和对虾样品的标准添加回收实验进行方法的验证,实验结果表明,平均回收率达到70％以上,相对标准偏差小于10％,符合药残检测要求。本方法可用于进行水产品中多种菊酯类农药残留的检测分析。     

中国沿海九种头足类齿舌的形态学

采用扫描电镜技术对9种头足类的齿舌进行了显微观察和比较研究。结果显示所研究的物种的齿舌均有7列纵向的齿组成,齿式为3·1·3。乌贼目的7个种(罗氏乌贼Sepiarobsoni、金乌贼S.esculenta、虎斑乌贼S..pharaonis、白斑乌贼S.latimanus、目乌贼S.aculeata、曼氏无针乌贼Sepiellamaindroni、柏氏四盘耳乌贼Euprymnaberryi)中央齿一列,具有一个齿尖;侧齿位于中央齿两侧各3列,分别称为第一、第二和第三侧齿,也称为侧齿,内缘齿和外缘齿;无缘板结构。长蛸Octopusvariabilis和短蛸O.ocellatus中央齿一列,分别有5个、3和5个齿尖,侧齿各3列,具有缘板。文中对九个种的齿舌结构以及彼此的异同进行了详细的描述和比较,并对乌贼类、蛸类和枪乌贼类彼此之间的齿舌关系以及功能差异进行了讨论。     

响应面法提取南极磷虾磷脂及其分子种组成的测定

南极磷虾(Euphausia superba)生物储量巨大,含有丰富的磷脂酰胆碱(phosphatidylcholine,PC),而PC是生物生长的必需磷脂。现今南极磷虾的研究主要针对磷虾油和蛋白,尚未见有PC分子组成的系统研究报道。该研究使用超声辅助Bligh Dyer脂质提取法提取南极磷虾中磷脂,并采用Box-Benhnken设计原理优化提取工艺,以正离子模式下胆碱碎片(m/z 184)为特异性碎片,利用鸟枪脂质组学法鉴定南极磷虾组织中的PC分子组成。结果表明,南极磷虾磷脂的最佳提取条件为超声时间21.0 min、超声温度30℃、溶剂用量3.1 mL,此条件下磷脂实际提取率的平均值为(7.59±0.03)%。利用鸟枪脂质组学法鉴定出南极磷虾中共含有36种PC分子,其中EPA/DHA脂肪酸链含量占47.75%,质量分数为269.82μg·g~(-1)。研究表明南极磷虾组织中含有丰富的EPA和DHA,而磷脂状态存在的ω-3脂肪酸具有较高的利用效率,这为开发南极磷虾类营养保健产品提供数据支持和理论基础。     

桑沟湾栉孔扇贝不同养殖方式及适宜养殖水层研究

在桑沟湾内，对栉孔扇贝Ｃｈｌａｍｙｓ（Ａｚｕｍａｐｅｃｔｅｎ）ｆａｒｒｅｒｉ（ＪｏｎｅｓｅｔＰｒｅｓｔｏｎ）的笼养与串耳养殖等不同养殖方式及不同水层（１ｍ、２ｍ、３ｍ、４ｍ）的养殖效果进行了综合试验和分析。结果表明：（１）串耳养殖的扇贝平均壳高增长比笼养扇贝生长快，两种方式效果差异极明显（Ｐ＜０．０１）；（２）串耳养殖方式以２ｍ为最佳养殖水层，其次为１ｍ和３ｍ，４ｍ水层最差，而且２ｍ与４ｍ的养殖效果存在明显差异（Ｐ＜０．０５）；（３）笼养方式的最佳水层为４ｍ，其养殖效果依次为４ｍ＞１ｍ＞３ｍ和２ｍ。试验显示，在不同的养殖方式下，栉孔扇贝最佳生长的养殖水层是不同的。本文还对产生这一差异的原因进行了分析讨论