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于 １９９６年在实验室对多刺探腹溞（Ｍｂｉｎａ ｍａｃｒｏｃｏｐａ）种群的增长率及相关生态学参数进行了研究．结果表明,３个温度梯度（２４、２８和３２℃）和３个面包酵母（Ｓａｃｃｈａｒｏｍｙｃｅｓ ｃｅｒｅｖｉｓｉ－ａｅ）密度（０．２５、２ ５和２５ ｘ １０_６ｃｅｌｌ．ｍＬ~（－１）下,以２８℃时内禀增长力（ｒ_ｍ）最高;２８℃时,面包酵母的投喂密度为２５×１０_６ｃｅｌｌ．ｍＬ_（－１）时,其ｒ_ｍ最大．温度２８℃,面包酵母密度为２５×１０_６ｃｅｌｌ．ｍＬ~（－１）时,该溞的繁殖前期最短,繁殖期和寿命均最长,并且怀卵量（每窝产仔数）最大．该溞的种群密度和瞬时增长率分别在接种后第７ｄ和第３－４ｄ达高峰．该搔批量培养时采收时间以第５ｄ为宜． 相似文献
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中国卤虫种群α—淀粉酶同工酶的基因表达特征 总被引：1，自引：0，他引：1
采用聚丙烯酰胺凝胶垂直板电泳法，对中国卤虫种群中２０个品系的α－淀粉酶（α－ＡＭＹ）同工酶基因的表达特征进行了分析。实验结果显示：Ａｒｔｅｍｉａｓｉｎｉｃａ和Ａ．ｐａｒｔｈｅｎｏｇｅｎｅｔｉｃａ各自有其独特的酶谱和基因型，Ａ．ｓｉｎｉｃａ的主要基因型为：０／ａｂ／ｂｂ和ａｂ／ａｂ／ａｂ，而Ａ．ｐａｒｔｈｅｎｏｇｅｎｅｔｉｃａ的主要基因型为０／ｂｂ／ａｂ和０／ｂｂ／ｂｂ，这可以作为区分两个种的重要生化指标；各品系间、品系内存在多态现象，并且平均杂合度值较高，与卤虫为了更好地适应不良的生活环境而积累大量有利基因和变异有关；从遗传距离和遗传相似系数可知Ａ．ｓｉｎｉｃａ和Ａ．ｐａｒｔｈｅｎｏｇｅｎｅｔｉｃａ有共同的祖先，两者分化时间大约在距今５７６万年至１００万年左右。 相似文献
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镉对中华绒螯蟹肝R—细胞亚显微结构及血清谷丙转氨酶(SGPT)活力的影响 总被引：6，自引：0，他引：6
作者提出镉对中华绒螯蟹肝胰脏R—细胞亚显微结构和血清谷丙转氨酶活力影响。在亚显微结构水平上,R—细胞中,受影响变化最明显的是线粒体;线粒体体积和其内膜嵴的破坏程度与介质镉浓度成显著的正相关关系;随镉浓度的升高,细胞器减少,内质网膨胀,细胞质和线粒体基质变稀薄。SGPT活力也随镉浓度升高而显著增大,并与R—细胞亚显微结构变化程度一致。本文还就处于不同镉浓度下的标本,与生理机能相联系的R—细胞形态变化的意义、R-细胞线粒体亚显微结构变化与SGPT活力变化的关系及SGPT活性变化的特点等进行了初步探讨。 相似文献
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Monthly investigatiom were made on the population of Chinese freshwater crab, Sinopotamon yangteskiense Bott, 1967 from April, 1984 to Match, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs' major development occured from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June-October. Females bearing eggs were taken from June-August, and crabs with young were found from July-October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-bom crabs become mature after 1-2 yeats. The sex ratio was approximately 1:1 in the overall population. However, the larger crabs are predominantly male. The age distribution of S. yangtsekinese was estimated from size frequency histograms. There were more adult crabs 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｉｍｐｏｒｔａｎｔｅｎｖｉｒｏｎｍｅｎｔａｌｆａｃｔｏｒｓａｆｆｅｃｔｉｎｇｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆＥｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓｌａｒ ｖａｅａｒｅｓａｌｉｎｉｔｙａｎｄｗａｔｅｒｔｅｍｐｅｒａｔｕｒｅ.ＤｉｆｆｅｒｅｎｔｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｓｔａｇｅｓｏｆＥｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓｒｅｑｕｉｒｅｄｉｆｆｅｒｅｎｔｔｅｍｐｅｒａｔｕｒｅａｎｄｓａｌｉｎｉｔｙ (ＩｎｇｌｅａｎｄＡｎｄｒｅｗｓ,1 976) .Ｃａ2 +ｃｏｎｔｅ… 相似文献
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EFFECTS OF TEMPERATURE AND Ca^2＋ ON THE LARVAL DEVELOPMENT OF THE DECAPODA CRUSTACEAN ： ERIOCHEIR SINENSIS 总被引：1，自引：0，他引：1
With increasing demand in China for the mitten crab larvae, understanding its survival mechanism gets more important. This research focused on the effects of temperature and Ca^2 on the larval growth and development. Eriocheir sinensis larvae were reared in laboratory under 21 different combinations of temperature (15, 20, 25℃) and Ca^2 content (120, 130, 140, 150, 160, 170, 180mg/l) and constant salinity (20) and pH (8), The results suggested that the survival rate increases with temperature and Ca^2 content. These combinations of temperature and Ca2 content maximized survival rate inour study and it may be the optimum water environmental conditions for culturing the larvae. To predict surviving larvae number under different water environmental conditions, 21 dynamic mathematical models were developed. This for the first time observation of the zoeal Ⅵ larvae of the Changjiang River E.sinensis population showed that they occurred under stressed water environmental conditions: temperature of 15℃ and Ca^2 content of 120,130mg/l. 相似文献