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Sex linkage among genes controlling sexually selected traits 总被引:8,自引:0,他引:8
Klaus Reinhold 《Behavioral ecology and sociobiology》1998,44(1):1-7
Using literature data on reciprocal crosses I estimated the influence of sex-chromosomal genes on morphological and behavioral
traits. To determine a special role of the sex chromosomes for sexually selected traits, I compared the estimated influence
of X-chromosomal genes on sexually selected traits with their estimated influence on traits not under sexual selection. About
one-third of the phenotypic variation in sexually selected traits is caused by X-chromosomal genes. There was, in contrast,
no significant influence of X-chromosomal genes on traits that were classified as not sexually selected. Sexually selected
traits thus seem to be influenced significantly more by X-chromosomal genes than traits not under sexual selection. Though
this differential influence of X-chromosomal genes cannot readily be explained with current theoretical knowledge, it may
shed some light on X-linked hybrid sterility and on the discussion between arbitrary and good-gene models for the evolution
of female choice.
Received: 30 January 1998 / Accepted after revision: 20 June 1998 相似文献
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采用海藻酸钠固定纳米铁制备海藻酸钠纳米铁小球,研究了海藻酸钠浓度、纳米铁含量、活性红X3B浓度、反应温度、pH值等对海藻酸钠固定化纳米铁小球还原活性红X3B的影响.采用高效液相色谱(HPLC)、紫外可见分光光度计(UV-Vis)、扫描电镜(SEM)、透射电镜(TEM)等方法分析污染物的还原脱色过程.结果表明,X3B的还原脱色获得了较好的效果,当温度25.0℃,海藻酸钠浓度2.0%,纳米铁含量2.0g/L,转速200r/min,pH值10.9时,反应720min后,25.0mg/L活性红X3B的脱色率达98.9%.海藻酸钠凝胶对活性红X3B没有吸附作用,海藻酸钠固定化纳米铁小球降解活性红X3B的主要机制为纳米零价铁的还原作用. 相似文献
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近30年来土壤种子库研究的回顾与展望 总被引:5,自引:0,他引:5
土壤种子库(Soil Seed Bank)是指单位面积的土壤及土壤表面的落叶层中所有具有生命力的种子的总和.由于土壤种子库在植被的更新和恢复、生物多样性的维护、植被的演替过程和扩散过程等方面都具有重要作用,近年来成为生态学和土壤学等学科的研究热点.文章查阅了近30年来发表的关于土壤种子库研究的代表性SCI论文,首次运用文献分析与管理软件Endnote X1和Refviz对该研究领域的相关文献进行了系统的分析,结果发现:有关土壤种子库论文发表数量逐年增长的同时,每个年代末会呈现一个明显的峰值.在此基础上,根据不同年代研究的内容和特点,初步将土壤种子库的研究划分为三个主要阶段:(1)土壤种子库研究的探索阶段(1978-1989年);(2)土壤种子库研究方法与内容的成熟阶段(1990-1999年);(3)土壤种子库理论体系与研究内容扩展阶段(2000年至现在),并对各个阶段的研究重点和主要研究成果进行了详细的综述.最后就长久土壤种子库调查、种子库年际变化、干扰影响机制等研究热点做了展望,为今后土壤种子库的研究工作提供了参考策略. 相似文献
167.
The effects of deoxynivalenol in different dose including 100, 200, 500, 1000, and 1500 µg/L on primary cranial osteoblasts from fetal mice were investigated. Fluorescence staining, flow cytometric measurement, 3-(4,5-dimethylthiazol 2-y1)-3,5-di-phenyltetrazolium bromide assay, quantitative PCR, and Western blot were used for the test. Mineralization and proliferation of osteoblasts decreased upon 100 µg/L and higher deoxynivalenol treatment and apoptosis of osteoblasts was increased upon 500, 1000, and 1500 µg/L deoxynivalenol treatment. Karyopyknosis, membrane breakage, and a decreased number of calcium nodes were also observed upon 500 µg/L deoxynivalenol treatment. The mRNA and protein levels of B-cell lymphoma-2-associated X protein were upregulated, B-cell lymphoma-2 protein downregulated with increasing concentrations of deoxynivalenol treatment and their ratio increased. Deoxynivalenol induces apoptosis of osteoblasts, suggesting a mechanism by which deoxynivalenol can affect murine skeletal development. 相似文献
168.
GAO Shang CHEN Cheng TAO Fang HUANG Minsheng MA Lihu WANG Zhonghu WU Linhui 《环境科学学报(英文版)》2009,21(7):940-947
The influence of a Reactive Brilliant Red X-3B (RBR X-3B) dye on the peroxidase isoenzyme of Phanerochaete chrysosporium was determined, and the biofilm structure in a white rot fungal continuous membrane bioreactor (MBR) was also investigated by scanning electron microscope (SEM). The variation of peroxidase isoenzyme and the decolorization rate in the continuous MBR were evaluated. The results showed that the 100 mg/L RBR X-3B could stimulate the production of the peroxidase isoenzyme in the shaking-flask culture. In addition, two new peroxidase isoenzyme bands with relative mobility (Rf) value of 0.27 and 0.28 appeared, but the activity was lower than the blank control of 11 d. In the continuous MBR, the system worked stably during the first 60 d, the main peroxidase isoenzyme bands existed and three new bands with Rf value of 0.10, 0.27, and 0.28 appeared. Meanwhile, the biofilm grew well and the average decolorization rate could reach 90.6%. But the bands of peroxidase isoenzyme decreased rapidly at day 65, only two bands with Rf value 0.24 and 0.26 existed, and the decolorization rate decreased to 78.3%. Therefore, 5 bottles of P. chrysosporium mycelial pellet were added into the MBR, and then the activity of the peroxidase isoenzyme and the decolorization rate had a slight recovery. Finally, the decolorization rate finally decreased to 75.2%. These results contribute to a comprehensive understanding of the variation of peroxidase isoenzyme and biofilm in continuous MBR by white rot fungi. 相似文献
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