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1.
A cell line,SHK,was derived from the kidney of spotted halibut Verasper variegates.The cell line was subcultured more than 40 passages in minimum essential medium(MEM)supplemented with fetal bovine serum(FBS)and 10 ng ml-1 basic fibroblast growth factor(bFGF).Cell morphology from primary culture and subculture was observed continuously by microscopy.The SHK cell line consisted predominantly of fibroblast-like cells.The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃.The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%.The doubling time of the cells was determined to be 44.8 h.Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number (2n=46).The cells were successfully transfected with green fluorescent protein(GFP)reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies.The cells were infected by lymphosystis disease virus(LCDV)and found to be susceptible to the virus in cytopathic effect(CPE)observation.The infection was confirmed by PCR and electron microscopy experiments,which proved the existence of the viral particles in the cytoplasm of the virus-infected cells.  相似文献   

2.
The FG-9307 cell line derived from the gill of flounder Paralichthys olivaceus was used in the present study to determine the acute cytotoxic effects of the organophosphorous pesticide, profenofos. It was found that the cell growth rate was markedly reduced by profenofos at the concentrations of 2.5, 5 and 7.5 mg/L tested; and that the fine structures of the cells were also altered by profenofos, as evidenced by dilation of nuclear membranes and mitochondria cristae, and presence of enlarged lysoscrneswith engulfed organelles and numerous vacuoles in the cytoplama. Probably, mitochondria, the cell ener-gy-generating sites, are the most prcrninent sites of profenofos cytotoxity in the cells. This seems to be the first report of the use of marine fish cell line for evaluation of the acute in vitro cytotoxicity of organophos-phorus pesticide.  相似文献   

3.
INTRODUCTIONPollutionofmarineecosystemposesaseriousthreattomarineorganismsandultimatelytheentireecosystem.Inrecentyears,organophosphorous(OP)pesticideshavelargelyreplacedorganochlorinepesticidesbecauseoftheirrapidbreakdowninwaterandtheirlowenvironmenta…  相似文献   

4.
The cytotoxicity of abamectin to the Gill Cell Line of Flounder (FG cell line) was examined in this study. It was found that the exposure of FG cells to abamectin caused the decreases of both cell growth rate and antioxidant enzyme activities,and the increase of intracellular O2- content. It was proposed that the reduction of antioxidant enzyme activities in FG cells caused the accu- mulation of O2- content in FG cells, leading to the change of cell morphology and even the death of cells. The results showed that FG cell line is suitable for the evaluation of the acute toxicity of abamectin.  相似文献   

5.
In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR, MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI.  相似文献   

6.
Three continuous marine fish cell lines of FG (i. e., Hounder Gill) from flounder (Paralichthys olivaceus) gill, SPH (i. e. , Sea Perch Heart) from sea perch (Lateolabrax japonicus) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream (Pagrosomus major) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns wasrelated to morphological changes of fish cells in vitro.  相似文献   

7.
Viral nervous necrosis(VNN)has emerged to become a major problem in the culture of larval and juvenile marine fish worldwide.Bioactive phytochemicals isolated from commonly available medicinal plants are often screened for their efficacy in controlling fish viral diseases.Occurrence of newer viral strains and resistance to existing antiviral drugs are problems currently as-sociated with treatment of VNN,which necessitates looking for alternate sources for effective antiviral drugs.The aim of the present study was to screen antiviral potential of gymnemagenol(C30H50O4)previously extracted from leaves of Gymnema sylvestre.The fish nodavirus,grouper nervous necrosis virus(GNNV)in infected Sahul Indian Grouper Eye(SIGE)cell lines were used to study the antiviral activity of gymnemagenol under in vitro conditions.The susceptibility of the virus to gymnemagenol was confirmed by measuring the viral titre(TCID50 mL?1)in virus-infected SIGE cells every 24 h.Gymnemagenol at 20 μg mL?1 inhibited the prolifera-tion of GNNV to 53% at the end of the 6th d by inhibiting the proliferation of GNNV-infected SIGE cells.The viable SIGE cells were reduced to 47% as determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.The viral titre(TCID50 mL?1)was also reduced to log 2.8 at the end of the 7th d in gymnemagenol-treated SIGE cells after inoculated with GNNV when compared to untreated control SIGE cell viral titre(log 4.1).Based on our results it can be concluded that gymnemagenol could be used as an antiviral agent against GNNV infection.  相似文献   

8.
空间拓扑关系是空间数据建模、空间查询、分析、推理、制图综合、数据质量控制、数据更新等的基础。目前空间拓扑关系研究的主要成果仍然集中在拓扑关系的描述方面,在计算方面的阐述都非常薄弱,不足以指导系统开发人员编程实现。本文研究了IR2中两个简单线目标间拓扑关系的计算方法,重点分析了线/线拓扑关系计算的特点,提出了一种基于线段的线/线拓扑关系计算方法,并用VC++采用底层开发模式实现了基本线/线拓扑关系的计算。  相似文献   

9.
A large yellow croaker,Pseudosciaena crocea,spleen(LYCS)cell line was established and the feasibility of using it for foreign gene transfection was evaluaed in this study.Primary culture of LYCS cells was initiated from spleen tissue pieces,which were cultured at 25℃ in Dulbecco’s modiced Eagle medium/F12 medium(DMEM/F12,1:1)(pH7.2),supplemented with 20% fetal bovine serum,carboxymethyl chitosan,chondroitin sulfate,basic fibroblast growth factor(bFGF)and insulin-like growth factor-I(IGF-I).The cultured LYCS cells,in fibroblast shape,proliferated to 100% confluency 20 days later.Chromosome analyses indicated that the LYCS cells exhibited chromosomal aneuploidy with a modal chromosome number of 48 which displayed the normal diploid karyotype of P.crocea(6m+6sm+36t,NF=60).A LYCS cell line,with a population doubling time of 48.7 h at passage 60,has been established and subcultured to passage 70.Transgenic feasibility test demonstrated that positive green fluorescence protein(GFP)expression was observed in LYCS cells after pcDNA3.1-GFP plasmid transfection.In conclusion,a continuous foreign gene trans-fection feasible LYCS cell line has been established successfully.The cell line might serve as a valuable tool for studies of transgenic breeding and has potential applications for different kinds of cytotechnological studies.  相似文献   

10.
以河流理想均衡剖面线为研究对象,深入探讨了地表水流对河床的塑造作用规律和河流均衡剖面线的形成机理,推导出均衡剖面线理论计算公式,并以黄河为例,结合我国自西向东三级地形结构,计算了三条均衡剖面线,L1为黄河全长均衡剖面线,L2和L3分别以托克托和松多为局部基准面计算的局部均衡剖面线,为黄河河床的演变规律研究和演化过程的计算机模拟提供了数学依据,同时对河流发育研究及侵蚀、搬运能力的探讨均有一定的理论意义。  相似文献   

11.
提出了一种地形图上等高线分离方法,方法建立在基于方向检测的线宽识别算法基础上,使等高线分离具有很强的宽度敏感性,同时由于在线宽识别过程中考虑了等高线的空间连续性,方法具有很好的分离效果.实践证明,算法可以为等高线进一步矢量化提供高质量的底图,减少等高线自动矢量化的后续编辑工作量,具有很强的实际意义和理论价值.  相似文献   

12.
本文针对移动平台内外存储容量小,处理器相对较弱的特点,通过数字高程模型(DEM,包括不规则三角网和规则格网),提出一种适用于移动平台的等高线直接生成剖面线的方法。与其他2种数字高程模型的剖面线生成方法的对比表明,本方法计算简单、运算量小、操作方便、成果图精度适宜,非常适合用于移动GIS。另外,针对在等高线生成剖面线过程中,路线处于2条等高线之间(即与等高线没有交点),无法求得路线高程值的情况,提出了通过作路线上任意点的水平和垂直方向直线,求得该直线与最邻近等高线的交点,利用4个交点的高程值求出路线上该点的高程值的方法。通过该方法,求出足够多高程点,进而生成剖面线。将本文提出的移动平台快速生成地形剖面线算法,应用于区域地质调查,较好地解决了实际应用中遇到的问题,取得了良好的效果。  相似文献   

13.
针对现有立体影像直线匹配方法中的线描述子只依赖局部灰度特征导致可靠性较弱的问题,本文提出了一种结合网状描述符和单应约束的直线匹配方法。① 利用线特征检测算法(Line Segment Detector, LSD)提取参考影像及搜索影像中的直线段;② 根据角度约束和核线约束确定候选直线,缩小直线搜索范围,并计算参考直线与候选直线的重叠部分以确保端点一致;③ 利用直线段固定邻域内的同名点对构建网状描述符,选择3组不同的同名点对分别计算直线相似值,取其中最大值作为直线段的最终相似度从而确定同名直线对;④ 将未搜索到同名点对的直线段利用单应性矩阵映射至搜索影像,并根据3个判别准则得到最终的匹配结果。为了验证算法的有效性及鲁棒性,本文选取国际公开的标准测试数据集中5组近景影像进行实验,并与现有3种具有代表性的算法进行对比。结果显示本文算法的准确度及有效性均优于对比的3种算法,在匹配准确率与运行效率上最高有16.1%与49倍的提升,对于不同条件下的影像均能取得良好的直线匹配结果。  相似文献   

14.
运用动力学原理,利用全球1988、1990、1991等年份的部分LAGEOS卫星激光测距资料解算武汉—上海的基线长度为657497.0507m,内符合精度优于2cm,相对精度为4×10-8,与IERS公布的结果接近。计算结果分析表明武汉SLR站的第三代测距仪运行系统稳定,没有明显的系统误差  相似文献   

15.
INTRODUCTIONAccumulatedevidencessuggestedaclosecorrelationbetweenneoplasticdiseaseofaquaticor ganismsandtheincreasingreleaseofgenotoxinsbyanthropogenicactivitiesintoaquaticenvironment(Mix ,1 986;Gardneretal.,1 991 ;GESAMP ,1 991 ) .Ithas,therefore,becomenecessarytoe…  相似文献   

16.
设M是有末端奇点的n维正规代数簇,L是M上的丰富线丛,(M,L)的数字有效值为τ=u/v(u、v是互素的正整数),φ:M→X是由(M,L)决定的nef-值态射,F是φ的一般纤维。通过研究τ的取值情况对(M,L)进行分类.给出了当u=n+1,n时(M,L)和(F,LF)的较完整的分类,推广了一些文献的结果。  相似文献   

17.
设M是有末端奇点的n维正规代数簇,L是M上的丰富线丛,(M,L)的数字有效值为τ=uv(u、v是互素的正整数),:M→X是由(M,L)决定的nef-值态射,F是的一般纤维。通过研究τ的取值情况对(M,L)进行分类,给出了当u=n+1,n时(M,L)和(F,LF)的较完整的分类,推广了一些文献的结果。  相似文献   

18.
地震趋势预测的一种新模型研究   总被引:5,自引:0,他引:5  
 本文根据自激励门限自回归模型原理,对多年的地震活动形势进行了分析,建立了用于地震大形势分析的客观化数值预测模式-在线预测模型。根据1980年以来中国大陆实际发生的地震资料对这一模型的可靠性进行了检验。统计结果表明,利用在线预测模型在对未来地震趋势进行预测时,其年度形势特征量的最大误差为0.3,平均误差为0.12;因此该模型能够比较客观地反映地震形势变化的自然特征及规律,较好的预测未来的地震活动趋势。这一模型的建立为促进地震趋势向客观化、定量化预测方向发展,提供了一种科学途径  相似文献   

19.
为正确分析和改进设计网具,采用悬链线与拖网配纲形状比较的方法,引伸配纲形变系数对设计网配纲进行合理性检验。并对有关计算方法进行推导和论证。  相似文献   

20.
A continuous marine fish cell line RSBF(i.e.Red Sea Bream Fin)was utilized to screen the cytotoxicity and genotoxicity of polyethylenimine(PEI)and nickel cholride(NiCl2)in this study on the deleterious effects of aquatic genotoxins on fish.At the 0.01 to 1μgml concentration tested,PEI had acute toxicity to the treated RSBF cells(IC50=1.12,0.92,0.88 and 0.64μg/ml PEI for time 0 h,24 h,48 h and 72 h after treatment,respectively)and markedly inhibited their proliferation in a dose-dependent manner.At the 0.001 to 5 μmol/L concentration tested,NiCl2 posed no acute toxicity but significantly stimulated their growth(107?214?of control).Random amplified polymorphic DNA(RAPD)technique was used to detect the genotoxic effects of PEI and NiCl2 by comparing the RAPD banding patterns of the control and treated cells.RAPD analysis indicated that at the concentrations tested,PEI was more genotoxic than NiCl2 to RSBF cells;that there was a slight dose-dependent response in the genotoxic effect of PEI bue not NiCl2;and that RAPD technique might provide a sensitive,non-specif-ic gentoxic endpoint.And the potent cytotoxicity and genotoxicity of PEI on fish cells showed that we should be cautious in utilizing it as gene vector in fish gene transfer and human gene therapy.  相似文献   

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