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91.
A previous molecular-genetic analysis of clonal cultures and single cells of Ostreopsis spp. that were isolated from Peter the Great Bay (the Sea of Japan) revealed three different genotypes according to the nucleotide sequences of ribosomal DNA (rDNA). Of these, Ostreopsis sp. 1 was earlier found only off the coast of Japan and described as being the most common and highly toxic. We have obtained further molecular evidence and have studied the morphological features of cells from one of the Ostreopsis strains with this genotype and some aspects of its growth at salinities of 24, 28, and 32‰. The results showed that in cells from the Russian coast of the Sea of Japan, the third apical (3') and the third precingular (3") plates do not adjoin one another, being separated by the elongated second apical (2') plate. Cells of Ostreopsis sp. 1 from the Russian coast are significantly larger than Ostreopsis sp. 1 cells with the same genotype from the coast of Japan. Salinity did not have a substantial effect on the growth of Ostreopsis sp. 1. The growth rate varied from 0.24 to 0.35 divisions per day, with maximum values at a salinity of 24‰. When salinity decreased to 24‰, the exponential growth phase was significantly extended and the maximum cell concentration doubled.  相似文献   
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We present a general framework for modelling adaptive trait dynamics in which we integrate various concepts and techniques from modern ESS-theory. The concept of evolutionarily singular strategies is introduced as a generalization of the ESS-concept. We give a full classification of the singular strategies in terms of ESS-stability, convergence stability, the ability of the singular strategy to invade other populations if initially rare itself, and the possibility of protected dimorphisms occurring within the singular strategy's neighbourhood. Of particular interest is a type of singular strategy that is an evolutionary attractor from a great distance, but once in its neighbourhood a population becomes dimorphic and undergoes disruptive selection leading to evolutionary branching. Modelling the adaptive growth and branching of the evolutionary tree can thus be considered as a major application of the framework. A haploid version of Levene's soft selection model is developed as a specific example to demonstrate evolutionary dynamics and branching in monomorphic and polymorphic populations.  相似文献   
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Diagnostic morphological characters of the juvenile Panchaetothripinae in New Zealand are illustrated. Keys developed enable colonies with only immature stages to be identified without needing to rear adults. Live larvae or larvae in ethanol are distinguished by the presence of expanded tips of body setae (Parthenothrips dracaenae), the absence of setae at the abdomen tip (Hercinothrips bicinctus), setae at abdomen tip not longer than abdominal tip width (Heliothrips haemorrhoidalis) and abdominal tip setae longer than abdominal tip width (Sigmothrips aotearoana, endemic species). The presence or absence of spine-like setae on abdominal segments 9 and 10, and the number and length of setae on the wing buds, enable identification of pupae. Abdominal spine-like setae were on the prepupa and pupa of H. bicinctus and S. aotearoana, species that pupate off the plant, and are probably defensive structures. This is the first record of spine-like setae on segment 10 of terebrantian pupae.  相似文献   
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11个绵羊品种MSTN基因非翻译区的变异   总被引:6,自引:1,他引:5  
孟详人  郭军  赵倩君  马月辉  关伟军  刘娣  狄冉  乔海云  那日苏 《遗传》2008,30(12):1585-1590
利用PCR-RFLP技术对特克塞尔羊、夏洛莱羊、小尾寒羊、蒙古羊、乌珠穆沁羊、阿勒泰羊、呼伦贝尔羊、塔什库尔干羊、多浪羊、湖羊和岗巴羊11个品种的345个个体的肌肉生长抑制素(Myostatin, MSTN)基因非翻译区(UTR)的变异进行了多态性分析。结果表明大小为271 bp和1 003 bp的扩增片段经限制性内切酶MboⅡ和BsaⅠ酶切后表现多态, 经卡方检验所有品种在该基因座位均处于平衡状态(P>0.05), 3种基因型在11个绵羊品种中的分布差异极显著(P<0.01)。通过限制性内切酶HpyCH4Ⅳ 酶切实验, 证明我国9个地方绵羊品种不存在特克塞尔绵羊中发现的导致肌肉发达的SNP位点, 并在3′UTR区发现了个别碱基突变位点能够形成miRNA作用的靶基序, 测序表明3′UTR区的突变频率较高。  相似文献   
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目的研究抗菌肽KSL及其衍生物KSL—W对种植体周围炎主要致病菌的体外抑菌效果。方法应用二倍稀释法检测KSL和KSL—W对血链球菌、具梭核杆菌和牙龈卟啉单胞菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC);MTT法检测KSL和KSL—W对成骨样细胞MG-63的细胞毒性。结果KSL和KSL—W对具梭核杆菌的MIC和MBC分别为0.0156mg/mL和0.0313mg/mL,对牙龈卟啉单胞菌的MIC和MBC分别为0.125mg/mL和0.5mg/mL,在0.5mg/mL的浓度范围内对血链球菌没有抑制作用;KSL和KSL-W在0.5mg/mL的浓度范围内没有细胞毒性。结论KSL和KSL—W没有细胞毒性,对具梭核杆菌和牙龈卟啉单胞菌具有抑制作用。  相似文献   
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Comparative biotesting was performed using embryos and larvae of the sea urchin Scaphechinus mirabilis and the microalga Dunaliella salina. These two species were taken as test organisms for estimating water quality in areas of various anthropogenic loads. Seawater from Nakhodka and Vostok bays, as well as from the southwestern part of Peter the Great Bay (Sea of Japan) near the Tumen River mouth, was tested. Water from Vostok and Nakhodka bays had a harmful effect on embryonic and larval development of the sea urchin. The algal culture kept in the water of Vostok Bay was depressed throughout the experiment, while development of the alga in the water from Nakhodka Bay hardly differed from the control but was unstable. Water from the southwestern part of Peter the Great Bay did not have any significant harmful effect on both test organisms. Embryos and larvae of the sea urchin S. mirabilis were several orders more sensitive to salinity changes and content of toxic agents; they responded more readily to changes in water quality than D. salina cells. Correspondingly, embryos and larvae of the sea urchin S. mirabilis were found to be a preferable test organism for assessment of pollution in various marine environments.  相似文献   
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