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T‐C Cheng Y‐S Lai I‐Y Lin C‐P Wu S‐L Chang T‐I Chen M‐S Su 《Journal of fish diseases》2010,33(2):161-169
Establishment and characterization of two cobia, Rachycentron canadum, cell lines derived from cobia brain (CB) and cobia fin (CF) are described. Caudal fin and brain from juvenile cobia were dissociated for 30 and 10 min, respectively, in phosphate‐buffered saline containing 0.25% trypsin at 25 °C. The optimal culture condition for both dissociated cells (primary cell culture) was at 28 °C in Leibovitz‐15 medium containing 10% foetal bovine serum. The cells have been sub‐cultured at a ratio of 1:2 for more than 160 passages over a period of 3 years. Origin of the cultured cells was verified by comparison of their sequences of mitochondrial cytochrome oxidase subunit I genes (cox I) with the cox 1 sequence from cobia muscle tissue. The cell lines showed polyploidy. No mycoplasma contamination was detected. Susceptibility to grouper iridovirus was observed for the CB cell line but not the CF cell line. Both cell lines expressed green fluorescent protein after being transfected with green fluorescent reporter gene driven by the cytomegalovirus promoter. 相似文献
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在15,17,21,25,29,33,35℃七种恒温下测定了二化螟各虫期的发育历期,并据此推算其发育起点和有效积温。结果为:卵11.8℃和83.5日·度;1龄幼虫11.6℃和71.7日·度;2龄幼虫10.9℃和92.4日·度,3龄幼虫11.6℃和74.1日·度;4龄幼虫11.3℃和77.2日·度;5龄幼虫10.7℃和86.6日·度,6龄幼虫10.5℃和79.5日·度;全幼虫期9.8℃和567.6日·度;预蛹12.8℃和50.7日·度;蛹10.9℃和118.9日·度;成虫产卵前期14.6℃和30.1日·度;全世代(雌)10.7℃和811.5日·度;利用Weibull函数拟合二化螟种群内幼虫个体间发育历期分布,当常态历期为x时,完成发育个体占总个体的比例F(x)可以下式表达: F(x)=1-Exp{-[(x-0.6546)/0.3795]~(3.8526)} 相似文献
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Huifeng Wu Baoan Hu Ying Ma Xiaoqin Cheng Fengfeng Kang Hairong Han 《Land Degradation u0026amp; Development》2023,34(7):2136-2146
Plant diversity is an important link between forest ecosystems' structural composition and functional processes. The simple composition of young plantations is weakening the ecological function of restored forest ecosystems in arid regions. The ecological drivers of the plant composition and dissimilarity in plantations remain unclear, especially in the early restoration stage. To fill the gap in knowledge of the differences in species composition in early restored ecosystems, and to reveal the influencing factors of similar species numbers with different compositional structures, based on species' presence-absence, abundance, and conspicuousness, we explored dissimilarity in the plant composition of young plantations in the loess hilly-gully region. Our results showed that differences in alpha diversity among plantations were minimal, while the differences in beta diversity were significant. Even if the species diversity of a plantation was low, communities with similar species richness used to have large dissimilarities in their species composition. Turnover components and balanced variation often contributed significantly to species compositional dissimilarity. Co-inertia analysis results showed species conspicuousness had the greatest consistency with observed environmental variables (RV = 0.65). The redundancy analysis and generalized diversity modeling results showed differences between the drivers of species diversity and dissimilarity. The primary influencing factors for alpha diversity were: soil water content, soil texture, soil total phosphorus, and soil organic carbon. Primary influencing factors for dissimilarity (beta diversity) were: soil nitrogen to phosphorus ratio, breast-height diameter, soil water content, and stand density. Collectively, plant taxa dissimilarity was influenced by soil nutrient ratio and community structure and plant taxa abundance was influenced by soil nutrient content. Our findings improve the understanding of the plantation species composition and facilitate the prediction of ecological functions. 相似文献
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厚环乳牛肝的原生质体分离与再生 总被引:2,自引:0,他引:2
探讨了外生菌根菌耳环乳牛肝(Suillusgrevillei)的原生质体制备及再生条件。用MYG培养基培养菌丝7天、宋用1.5%Lywallzyme,以0.6mol甘露醇为稳渗剂,在酶解液pN值5.5,温度31℃,酶解4hr的条件下,每0.1g湿菌丝的原生质体产量这6×10 ̄6/ml。用SO培养基培养菌丝能提高原生质体产量,但再生率下降。综合产量和再生率考虑以MYG培养菌丝效果较好。 相似文献
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郭玲玲 《金陵科技学院学报》2002,18(1):81-84
传统教育面临着后现代教育和网络迅猛发展的严峻考验。时代的发展和变革也要求教育的改革。了解后现代教育的意义和重要性能 ,促使“精英教育”、“制度化教育”向适应时代和社会发展需要的“全民教育”、“终身教育”转化 相似文献
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