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101.
中国中生代晚期蛇蛉化石研究(蛇蛉目:巴依萨蛇蛉科,中蛇蛉科,异蛇蛉科) 总被引:9,自引:1,他引:9
本文根据最新采获的保存完好的蛇蛉化石,对中国古生代晚期蛇蛉化石巴依萨蛇蛉科,中蛇蛉科和异蛇蛉科的有关属种的构造特征,分类位置和异我进行新的补充和厘定,建立4个新属:野蛇蛉属Rudiraphidia gen。nov,小蛇蛉属Mioraphidia gen。nov。普蛇蛉属Xynoraphidia gen。nov。丽蛇蛉属Caloraphidia gen,nov;7个新种;美脉巴依萨蛇蛉Baissop 相似文献
102.
目的:研究去泛素化酶USP13对人慢性髓系白血病细胞系K562增殖和凋亡的影响,并进行初步的机制探究。方法:构建pLKO.1-shUSP13-GFP慢病毒干涉载体,慢病毒包装后感染并建立稳定敲低USP13的K562细胞株。免疫印迹检测K562细胞中USP13蛋白的敲低效率。流式细胞术分析敲低USP13对K562细胞增殖和凋亡的影响。免疫共沉淀和蛋白质泛素化实验探究USP13调控K562细胞的分子机制。结果:成功构建pLKO.1-shUSP13-GFP慢病毒干涉载体,同时利用慢病毒体系获得稳定敲低USP13的K562细胞株。流式细胞术结果显示,敲低USP13促进K562细胞凋亡、抑制细胞增殖。分子机制研究发现,敲低USP13通过增强c-Myc泛素化进而导致其蛋白质水平降低。结论:初步揭示了USP13调控K562细胞增殖和凋亡的分子机制,为治疗慢性髓系白血病提供了潜在的靶点。 相似文献
103.
104.
对串果藤属(Sinofranchetia)叶的个体发育过程进行了观察,结果表明,其叶原基在发生时为不分裂的,其后叶原基两侧产生两个突起,形成两个侧生小叶原基,而中央部分形成中央小叶的原基。同时对串果藤属植物叶原基发生的类型等问题进行了讨论。 相似文献
105.
广东省烟粉虱蚜小蜂种类及种群动态调查初报 总被引:10,自引:1,他引:10
通过调查采集和鉴定 ,初步获得了广东省内烟粉虱蚜小蜂 6种 ,其中隶属于恩蚜小蜂属EncarsiaFoerster的有 4种 ,隶属于桨角蚜小蜂属ErtmocerusHaldeman有 2种。调查发现 ,蚜小蜂在蔬菜和园林植物上的寄生动态有一定的规律 ,4月中旬至 6月下旬和 9月下旬至 1 1月下旬寄生率较高 ,6月下旬至 8月上旬和 1 1月下旬至翌年 2月下旬寄生率较低。初步确定双斑恩蚜小蜂Encarsiabimaculata和桨角蚜小蜂Eretmocerussp .为广东省内烟粉虱的寄生蜂优势种类。 相似文献
106.
Ya-Juan Li Yi Tian Ming-Zhao Zhang Ping-Ping Tian Zhuo Yu Syuiti Abe Katsutoshi Arai 《Ichthyological Research》2010,57(4):358-366
The chromosomes of the diploid and tetraploid loach Misgurnus anguillicaudatus were analyzed by staining with Ag, chromomycin A3 (CMA3)/distamycin A (DA), and DA/4′,6-diamidino-2-phenylindole (DAPI), and using fluorescence in situ hybridization (FISH) with
5.8S + 28S rDNA as a probe. Nucleolus organizer regions (NORs) were mapped to the telomeric region of the short arms of the
largest (first) metacentric chromosome pair in the diploid loach with 2n = 50 and the homologous quartet in the tetraploid loach with 4n = 100. The NORs were positive at the same region of the first metacentric chromosome for Ag and CMA3/DA stainings, but negative for DA/DAPI staining. Four signals at the homologs within the same quartet suggest the duplication
of the entire genome from diploid to tetraploid status. However, a size difference was detected between the rDNA signals by
FISH and CMA3 banding. 相似文献
107.
108.
Stereoselective differences in pharmacokinetics between clausenamide (CLA) enantiomers have been found after intravenous and oral administration of each enantiomer to rats. The differences could be associated with protein binding of CLA enantiomers. By equilibrium dialysis methods, the binding of CLA enantiomers to rat plasma protein was investigated. The results showed that mean percentages of (-) and (+)CLA in the bound form were 28.5% and 38.0%, respectively, indicating that the unbound fraction of (-)CLA was higher than that of (+)CLA, which provided an explanation for stereoselective pharmacokinetics of CLA enantiomers in rats. The results also showed that there were species differences in plasma protein binding of (-)-isomer between rats (28.5%) and rabbits (47.2%). Furthermore, effects of plasma protein binding on the distribution of CLA enantiomers to their possible target tissues were observed. The amount of (-)CLA in brain was greater than that of (+)CLA 15 min after administration of each enantiomer to rats. But the results were reverse at 4 h postdose. Further studies in distributional kinetics showed that (-)CLA had a more rapid absorption and distribution to hippocampus, cortex, and cerebellum than (+) CLA. (+)CLA had greater values for T(max), t(1/2) (beta), and AUC(0) (-->infinity), and smaller ones for CL/F and V(d)/F than its antipode. The data indicated that the distribution of (-) and (+)CLA in their target tissues was stereoselective. The stereoselective distribution might be involved in the metabolism and transport of two enantiomers in the central nerve system. 相似文献
109.
Background
Bryopsis hypnoides Lamouroux is a siphonous green alga, and its extruded protoplasm can aggregate spontaneously in seawater and develop into mature individuals. The chloroplast of B. hypnoides is the biggest organelle in the cell and shows strong autonomy. To better understand this organelle, we sequenced and analyzed the chloroplast genome of this green alga.Principal Findings
A total of 111 functional genes, including 69 potential protein-coding genes, 5 ribosomal RNA genes, and 37 tRNA genes were identified. The genome size (153,429 bp), arrangement, and inverted-repeat (IR)-lacking structure of the B. hypnoides chloroplast DNA (cpDNA) closely resembles that of Chlorella vulgaris. Furthermore, our cytogenomic investigations using pulsed-field gel electrophoresis (PFGE) and southern blotting methods showed that the B. hypnoides cpDNA had multimeric forms, including monomer, dimer, trimer, tetramer, and even higher multimers, which is similar to the higher order organization observed previously for higher plant cpDNA. The relative amounts of the four multimeric cpDNA forms were estimated to be about 1, 1/2, 1/4, and 1/8 based on molecular hybridization analysis. Phylogenetic analyses based on a concatenated alignment of chloroplast protein sequences suggested that B. hypnoides is sister to all Chlorophyceae and this placement received moderate support.Conclusion
All of the results suggest that the autonomy of the chloroplasts of B. hypnoides has little to do with the size and gene content of the cpDNA, and the IR-lacking structure of the chloroplasts indirectly demonstrated that the multimeric molecules might result from the random cleavage and fusion of replication intermediates instead of recombinational events. 相似文献110.
方便高效的保存方法是开展动物肠道微生物研究的重要前提,用T-RFLP(末端限制性片段长度多态性)结合16S rDNA分析评估了野外采样常用的DETs(20%DMSO,0.25 M sodium-EDTA,100 mM Tris,pH 7.5,and NaCl to saturation)缓冲液对不同保存时间(24h,7天,30天,90天)粪便样品肠道微生物DNA的保存效果。结果表明,DETs保存在30天保存时间内微生物群落结构无显著变化,95.6%的T-RFs仍然存在,能效好的保护肠道微生物DNA。 相似文献