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221.
赤魟软骨血管生成抑制因子的分离纯化 总被引:2,自引:0,他引:2
确定了制备高纯度赤魟软骨血管生成抑制因子的纯化工艺,并通过胶原酶模型、CAM模型验证其生物学活性。正交实验确定了赤魟软骨组织抽提的最佳条件,抽提产率可达0.84%。丙酮分级沉淀对抽提产物进行粗分离,25~35%的丙酮分级产物的CAM血管生成抑制率达85%。优化离子交换层析、凝胶过滤、反相层析的条件,可进一步有效的获得高纯度的赤魟软骨血管生成抑制因子-I(DCAIF-I)。SDS-PAGE-考马斯亮蓝染色显示为一条带,分子量为62 kDa。活性验证结果表明,DCAIF-I对胶原酶具有一定的抑制活性,抑制率为36.3%,对CAM血管生成的抑制活性具有一定的剂量依赖关系。 相似文献
222.
Diagnosis of trace metal contamination in sediments: the example of Ensenada and El Sauzal, two harbors in Baja California, Mexico 总被引:1,自引:0,他引:1
Huerta-Diaz MA Delgadillo-Hinojosa F Hernández-Ayón M Segovia-Zavala JA García-Esquivel Z López-Zárate H Siqueiros-Valencia A Galindo-Bect S 《Marine environmental research》2008,66(3):345-358
Total metal concentrations in sediments from within Ensenada and El Sauzal Harbors are generally higher than at the mouths. Grain-size analyses suggested that this enrichment could be due to the presence of fine-grained sediments in the inner part of the harbors rather than to anthropogenic perturbations. The (Me/Al)(sample) ratios for Pb, Co, Ni and Fe were significantly higher for Ensenada Harbor relative to El Sauzal Harbor, whereas the ratios for Cd, Mn, Zn and Cu were statistically equivalent for both harbors. Calculated enrichment factors [EF(Me)=(Me/Al)(sample)/(Me/Al)(shale)] indicated that the metals showing slight enrichment were those associated with anthropogenic contamination (Pb, Zn), or probably related to primary productivity in the water column (Cd, Co). The levels of most of the metals were not greatly enriched, a consideration that is of the utmost importance when contamination issues are at stake. 相似文献
223.
224.
国际Argo计划执行现状剖析 总被引:1,自引:0,他引:1
国际Argo计划自2000年实施以来,世界上25个国家和团体已经在全球海洋中布放了5000余个Argo浮标,其中在海上正常工作的浮标已经超过3000个。这标志着全球Argo实时海洋观测网已经全面建成。文中将系统介绍国际Argo计划主要成员国在浮标布放、回收和Argo资料管理等方面所作出的贡献,以帮助读者对这21世纪的重大国际海洋观测计划有一较全面、深入的了解。 相似文献
225.
In crustaceans, the male sexual dif ferentiation and maintenance are specially regulated by androgenic gland(AG). However, little is known about the genes involved in the regulation process.RNA-Seq was performed on AG with ejaculatory duct(AG_ED) and ejaculatory duct(ED) as control in Eriocheir sinensis, one of the most important economic and ?shery crabs with typically sex dimorphism. A total of 925 unigenes were identi?ed as dif ferentially expressed genes(DEGs) and the expression of nine genes randomly selected was con?rmed by qRT-PCR. 667 unigenes were up-regulated in AG_ED, being supposed to be AG preferential genes. Among them, the full length of i nsulin-like androgenic gland factor( IAG) cDNA named as Es-IAG was obtained as a logo gene of AG, which together with the genes i nsulin-like receptor( INR), and s ingle insulin binding domain protein( SIBD), might constitute the sex regulation pathway. Several sex related genes were identi?ed, and their function will have to be investigated. Also,the identi?cation of j uvenile hormone epoxide hydrolase 1( JHEH1), ecdysteroid 22-hydroxylase( DIB) and e cdysone receptor( ECR) preliminarily clari?ed the molecular regulation mechanism of eyestalk-AG-testis axis, which plays important roles in molting and reproduction. The results will enhance our understanding for the molecular basis of the AG involved in male sex regulation in crabs. 相似文献
226.
基于综合环境因子的协同克里金法分析茎柔鱼资源丰度空间分布 总被引:1,自引:1,他引:1
茎柔鱼是我国重要的远洋捕捞对象之一,研究其资源丰度空间分布问题,有助于更好地理解茎柔鱼的生态习性,并提高我国鱿钓渔船的生产效率。本文利用上海海洋大学鱿钓技术组提供的2003-2012年6-9月秘鲁外海茎柔鱼捕捞数据,结合海表面温度(SST),海表面高度(SSH),海表面盐度(SSS)和叶绿素浓度(Chl a)进行协同克里金插值预测其资源丰度的空间分布。为了解决协同克里金插值中4个环境因子的权重问题,本文将4个环境因子进行归一化处理,利用主成分分析方法将其整合为单一综合环境因子,以此作为协变量。将综合环境因子与单位捕捞努力量渔获量(CPUE)进行相关性检验后进行协同克里金插值,根据平均误差(ME),均方根误差(RMSE)和标准化均方根(RMSSE)对插值结果评价,探讨此种方法的可行性。研究结果认为:(1)主成分分析方法获得的6-9月份的综合环境因子均与CPUE具有显著相关性;(2)6-7月份ME分别为0.002 6和0.002 5,预测准确性很高,平均预测结果稍高于实际观测值;而8-9月份的ME分别为-0.007 8和-0.000 2,预测准确性较高,平均预测结果稍低于实际观测值。6月份的RMSE估值精度最高,8月份的估值精度最低。6-7月份的RMSSE值小于1,说明都高估了预测的不确定性,8-9月份的RMSSE值大于1,说明都低估了预测的不确定性,则在6-9月份中的预测精度和准确性上会有一定程度的偏差。从ME、RMSE和RMSSE三者综合来看,6-9月的预测值具有一定的可靠性。 相似文献
227.
运用多元统计方法识别浙北海域两个典型港湾的水质状况 总被引:1,自引:0,他引:1
浙北海域两个典型港湾,杭州湾与象山港的水体污染状况日趋严重。本文运用多元统计方法,对分析了研究海域水体的物理及生物地球化学要素进行了量化分析。结果表明,根据物理及生物地球化学特性,层次聚类分析可将研究海域划分为两个不同的子区域;主成分分析分别在杭州湾和象山港识别出3个潜在的污染源,且陆源径流的输入、沿岸工业排污以及自然演化过程为主要源头。因此,研究海域的生态环境保护刻不容缓,应该立即采取相关措施。 相似文献
228.
本文对取自罗斯海陆架的JB04岩心沉积物进行AMS14C测年、粒度、有机碳等测试,结合沉积物粒度组分因子分析,研究该岩心的沉积学记录,探讨其古海洋学意义。结果显示:JB04岩心沉积物的底部年龄为15 ka;沉积物粒度组分因子分析提取出3个环境敏感粒级,分别代表正常冰海沉积、低能海洋沉积和高能海洋沉积;综合沉积物岩相及沉积物组成特征,可以将岩心分为4段,从底部到顶部依次为主要受冰盖刮蚀影响的冰盖下沉积、属低能海洋环境的冰架下沉积、属高能海洋环境的冰架前缘沉积和主要受冰山影响的季节性海冰区沉积。该岩心的沉积地质记录及其古海洋学研究对全面认识罗斯海的海洋环境演变具有重要的意义。 相似文献
229.
《Marine Policy》2015
Fishing fleets are subject to numerous factors that affect economic performance, making identification and attribution of such impacts difficult. This paper separately identifies the effects of changing input and output prices, fishery management, and quota allocations on total factor productivity using a Lowe Index. Indices account for technical change and decompose productivity estimates into its technical, environmental, and scale-mix components. This results in measures that reflect shifts in the production frontier, and movements by vessels toward and around the frontier, to capture economies of scale and mix after a policy shift to a catch share program that includes fishing cooperatives and a limited access fishery. The difference between cooperative and limited access vessels is exploited to compare the changes in economic performance between the groups after the introduction of the shift to catch shares and cooperative management, which allowed the vessels to improve the timing and coordination across multi-species fisheries and to decrease incidental catch of quota-limited bycatch species that had closed the target fisheries prematurely in the past. Results indicate that total factor productivity increased significantly after the move to a catch share program, largely due to increases in technical change that shifted out the production frontier of the fishery. 相似文献
230.
Sea surface temperature SST obtained from the initial version of the Korea Operational Oceanographic System(KOOS) SST satellite have low accuracy during summer and daytime. This is attributed to the diurnal warming effect. Error estimation of SST data must be carried out to use the real-time forecasting numerical model of the KOOS. This study suggests two quality control methods for the KOOS SST system. To minimize the diurnal warming effect, SSTs of areas where wind speed is higher than 5 m/s were used. Depending on the wind threshold value, KOOS SST data for August 2014 were reduced by 0.15°C. Errors in SST data are considered to be a combination of random, sampling, and bias errors. To estimate bias error, the standard deviation of bias between KOOS SSTs and climatology SSTs were used. KOOS SST data yielded an analysis error standard deviation value similar to OSTIA and NOAA NCDC(OISST) data. The KOOS SST shows lower random and sampling errors with increasing number of observations using six satellite datasets. In further studies, the proposed quality control methods for the KOOS SST system will be applied through more long-term case studies and comparisons with other SST systems. 相似文献