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应用751-GW分光光度计比色法测定了广西自然种群泥蚶蛋白酶活性与pH值和温度的关系,所有数据都检验其正态性和方差同质性,并用Statistica软件包分析处理,得到如下主要结果:在温度为40℃的条件下,最适pH值为2.6和4.6,两者对应的蛋白酶活力分别为(0.68±0.03)u/g和(0.59±0.03)u/g,pH值为6.6以后的酶活力迅速减弱且变化趋缓;在pH值为6.6的条件下,随着温度(4~38℃)升高酶活力逐渐增强,最适温度为38℃,其对应的酶活力为(0.40±0.01)u/g,38℃以后酶活力逐渐减弱。这些结果表明,不同pH值和不同温度的蛋白酶活力经单因素方差分析均差异显著。广西自然种群泥蚶蛋白酶与皱纹盘鲍最适pH值的对比分析表明,该泥蚶存在胃蛋白酶。 相似文献
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泥蚶(Tegillarca granosa)个体发育过程中同工酶基因表达与调控的研究 总被引:4,自引:2,他引:4
采用不连续垂直聚丙烯酰胺凝胶电泳法,对泥蚶(Tegillarca granosa Linnaeus)19个发育阶段的ADH、LDH、EST、IDH、ALP、MDH、GDH、POD、ATPase和ME等10种同工酶的基因表达进行检测分析。结果表明,泥蚶在个体发育过程中随着机体分化和生理活动的改变,同工酶基因的表达呈现出显著的时序变化。在10种酶中,LDH和ATPase两种酶的所有酶带及EST、MDH和ME等的部分酶带在各个发育阶段持续表达,其他酶带只出现在发育阶段的某一或某些阶段,并且表现出了与泥蚶营养方式、代谢形式等生理活动的关联性。在泥蚶的个体发育阶段过程中,IDH、MDH、GDH、ME、ALP等5种酶在32细胞期表达的酶带数剧增,因此32细胞期可能是合子基因表达启动的时间;ADH、EST、LDH、MDH、GDH、ME等6种酶在泥蚶的附着变态期酶带大幅减少或产生新酶带,可能与泥蚶附着期运动方式、代谢强度及生活环境的改变有关。 相似文献
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枯草芽孢杆菌对泥蚶及养殖底泥中细菌总数和弧菌总数的影响 总被引:1,自引:0,他引:1
以平板计数法,研究了不同浓度枯草芽孢杆菌(Bacillus subtilis)对泥蚶(Tegillarca granosa)及养殖底泥中细菌总数和弧菌总数的影响.试验分为1×10~6,5×10~6和10×10~6CFU/L 3个浓度试验组和对照组,试验共进行28 d,在第0、7、14、21和28天时采底泥和泥蚶,采用平板计数法检测细菌总数和弧菌总数.结果显示,在投施枯草芽孢杆菌后7 d内,养殖底泥和泥蚶体内细菌总数均呈明显上升趋势(P<0.05),7~28 d内缓慢下降,但差异不显著(P<0.05);投施枯草芽孢杆菌后,各试验组底泥和泥蚶体内弧菌总数显著低于对照组(P<0.05),5×10~6CFU/L和10×10~6 CFU/L试验组弧菌总数显著低于1×10~6CFU/L试验组(P<0.05).结果表明枯草芽孢杆菌具有抑制弧菌增殖的作用,枯草芽孢杆菌可应用于泥蚶池塘养殖. 相似文献
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Environmental planning is an arena of policy making in which formal public deliberation is among the most extensive. At the same time, environmental disputes can also be among the most resistant to resolution, often becoming entangled in issues that some describe as “intangible”. The discourse is largely structured by regulatory frameworks, such as environmental impact assessment laws and procedures, which focus primarily on operational rights (what one can or cannot do where and when) and tangible impacts on the physical or natural environment. A comparative case study of mariculture in Hawai‘i reveals that a large measure of public concerns focused on collective choice rights (who has a right to make which decisions on behalf of whom) and the more intangible impacts to the social or cultural environment. These concerns are often nested in a historic context that has implications for the social processes that they create. The findings from this study imply a need for more structured or systematic ways to deliberate issues of collective choice rights alongside operational rights within the larger process of environmental planning. 相似文献
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湖盆浊积砂体及类型研究 总被引:3,自引:0,他引:3
浊积砂体一直是人们关注的焦点.随着含油气盆地勘探程度的不断增高,"九五"以来,陆相含油气区逐渐进入以隐蔽油气藏为主要目标的勘探阶段,深水浊积砂体作为油气的储集层,成为石油地质领域的一个研究热点,其中,浊积砂体的类型划分和形成机制尤其是人们关注的焦点.本文介绍了浊流及相关重力流的有关概念,对浊流沉积研究进展及现状作了简介,最后对湖盆浊积砂体多种分类方案作了详细的阐述,并以山东济阳坳陷发育的浊积岩为例偿试湖相浊积砂体的分类,总结归纳了湖相浊积砂体的类型、识别标志和分布规律. 相似文献
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Francesco Nencioli Victor S. Kuwahara Tommy D. Dickey Yoshimi M. Rii Robert R. Bidigare 《Deep Sea Research Part II: Topical Studies in Oceanography》2008,55(10-13):1252
E-Flux III (March 10–28, 2005) was the third and last field experiment of the E-Flux project. The main goal of the project was to investigate the physical, biological and chemical characteristics of mesoscale eddies that form in the lee of Maui and the Island of Hawai’i, focusing on the physical–biogeochemical interactions. The primary focus of E-Flux III was the cyclonic cold-core eddy Opal, which first appeared in the NOAA GOES sea-surface temperature (SST) imagery during the second half of February 2005. During the experiment, Cyclone Opal moved over 160 km, generally southward. Thus, the sampling design had to be constantly adjusted in order to obtain quasi-synoptic observations of the eddy. Analyses of ship transect-depth profiles of CTD, optical and acoustic Doppler current profiler (ADCP) data revealed a well-developed feature characterized by a fairly symmetric circular shape with a radius of about 80 km. Depth profiles of temperature, salinity and density were characterized by an intense doming of isothermal, isohaline and isopycnal surfaces. Isopleths of nutrient concentrations were roughly parallel to isopycnals, indicating the upwelling of deep nutrient-rich water. The deep chlorophyll maximum layer (DCML) shoaled from a depth of about 130 m in the outer regions of the eddy to about 60 m in the center. Chlorophyll concentrations reached their maximum values in Opal's core region (about 40 km in diameter), where nutrients were upwelled into the euphotic layer. ADCP velocity data clearly showed the cyclonic circulation associated with Opal. Vertical sections of tangential velocities were characterized by values that increased linearly with radial distance from near zero close to the center to a maximum of about at roughly 25 km from the center, and then slowly decayed. The vertical extent of the cyclonic circulation was primarily limited to the upper mixed layer, as tangential velocities decayed quite rapidly within a depth range of 90–130 m. Potential vorticity analysis suggests that only a relatively small (about 50 km in diameter) and shallow (to a depth of approximately 70 m) portion of the eddy is isolated from the surrounding waters. Radial movements of water can occur between the center of the eddy and the outer regions along density surfaces within an isopycnal range of σ–t23.6 () and σ–t24.4 (). Thus the biogeochemistry of the system might have been greatly influenced by these lateral exchanges of water at depth, especially during Opal's southward migration. While the eddy was translating, deep water in front of the eddy might have been upwelled into the core region, leading to an additional injection of nutrients into the euphotic zone. At the same time, part of the chlorophyll-rich waters in the core region might have remained behind the translating eddy and, thus contributed to the formation of an eddy wake characterized by relatively high chlorophyll concentrations. 相似文献