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181.
凤眼莲能够吸收和在体内聚集外源苯酚,体内的酸含量随着环境中酚浓度的上升而上升。从生长于合酚培养液中的凤眼莲体内能够检测到酚糖苷,说明凤眼莲体内有酚精苷转移酶的存在。浓度小于50mg/L的外源酚能提高凤眼莲体内的多酚氧化酶和过氧化物酶的活性。多酚氯化酶与过氧化物酶在线粒体和微粒体中均有不同程度的分布,而酚糖苷转移酶则不存在于这些细胞器中。 相似文献
182.
本实验构建了在大肠杆菌中能表达玉米叶绿体CF1完整β亚基、缺失N端23个氨基酸残基的β亚基以及完整ε亚基的表达质粒。SDS-聚丙烯酰胺凝胶电泳及Westernblot实验表明,在分别含这些表达质粒的细菌中β、ε亚基蛋白的合成量在诱导3h后即达到饱和,其含量各占细菌体总蛋白的10%左右。这些表达产物在细菌体中形成不溶性的包含体。可通过对菌体蛋白的分级分高,将表达产物溶于5mol/L的尿素溶液中。 相似文献
183.
家鸡和原鸡的线粒体DNA多态性比较 总被引:17,自引:0,他引:17
本文运用11种限制性内切酶分析了家鸡(茶花鸡、尼西鸡、大理漾濞黄鸡)和原鸡共10只个体的线粒体DNA限制性片段长度多态性(RFLP),平均每个个检测到的片段为40条左右。但仅发现3种变异的限制性片制性格局,即StuI-B,Eca-I-b和RI-B.其中StuI-B和ScaI-B为首次报道,而且均为原鸡所物有,EcoRI-B则为大理漾濞黄鸡所特有。茶花鸡和尼西鸡拥有完全相同的限制性格局。经过计算,原 相似文献
184.
大阪鲫鱼两种卵黄蛋白免疫细胞化学的研究 总被引:4,自引:0,他引:4
以电泳提纯的卵黄脂磷蛋白和卵黄蛋白L制备兔抗两种蛋白的抗血清,采用PAP法对性腺成熟雌性大阪鲫鱼的肝细胞和卵母细胞进行两种蛋白免疫细胞化学位研究。肝细胞的粗面内质网上有强烈的卵黄脂磷蛋白的阳性反应,特别是在线粒体的基质中也发现卵黄脂磷蛋白的阳性反应,而另外一种类似于卵黄高磷蛋白的卵黄蛋白-卵黄蛋白L在肝细胞的粗面内质网和线粒体均呈现阴性反应,提示卵黄脂磷蛋白的前体物质存在于肝细胞的粗面内质网和线粒 相似文献
185.
排卵,排精前后文昌鱼体内GnRH的研究 总被引:1,自引:1,他引:0
利用放射免疫分析法测定了排卵、排精前后青岛文昌鱼体内促性腺激素释放激素(GnRH)的含量变化,并通过高效液相色谱比较了雌、雄文昌鱼性腺及除性腺外体部GnRH的种类和含量的异同。结果表明:1)生殖过程中雌、雄文昌鱼体内GnRH含量的变化规律不同;雌性文昌鱼体内GnRH总含量在排卵时有所下降,排后12小时政策最为明显,以后逐渐上升到排前水平;雄性文昌鱼仅在排精时有所下降,2小时后即稳定在排水平。2)文 相似文献
186.
Wen Wang Ai-hua Liu Shi-ying Lin Hong Lan Bing Su De-wen Xie Li-ming Shi 《Biochemical genetics》1994,32(9-10):371-378
mtDNA genotypes of six domestic horses (three adult short horses whose heights are under 1 m and three common domestic horses) from a small region of 15 km2 in Malipo county of Yunnan province of China were investigated by the technique of restriction fragment length polymorphism (RFLP) with 16 restriction endonucleases which recognize 6-bp sequences. An average of 56 fragments for an individual was obtained. Unlike other domestic animals, this population of horses exhibits high mtDNA genetic diversity. Each of the six horses has a specific mtDNA genotype showing a pattern of multiple maternal origins, as suggested by fossil and literature records. We think the population of horses is an amazing seed-resource pool of horses and hence deserves to be paid more attention from the view of conservation genetics. However, it is also remarkable that we did not find any typical mtDNA genetic markers which would discriminate between short horses and common domestic horses. 相似文献
187.
Intraspecific cleaning behaviour of diseased juvenile Cyprinus carpio L, in experimental tanks in Wuxi, China has been observed and is described. 相似文献
188.
A Suppressor of a Mating-Type Limited Zygotic Lethal Allele Also Suppresses Uniparental Chloroplast Gene Transmission in Chlamydomonas Monoica 下载免费PDF全文
Uniparental inheritance of Chlamydomonas chloroplast genes is thought to involve modification of maternal (mt(+)) chloroplast genomes to protect against a nuclease that is activated after gamete fusion. The mating-type limited mtl-1 mutant strain of Chlamydomonas monoica is unable to protect mt(+)-derived chloroplast DNA. Zygotes homozygous for mtl-1 lose all chloroplast DNA and fail to germinate. We have selected for suppression of this zygote-specific lethality, and have obtained 20 mutant strains that produce viable homozygotes despite the continued presence of the mtl-1 allele. Genetic analysis indicates that the suppressor mutations are all recessive alleles at a single locus (sup-1) which is unlinked to mtl-1. Crosses between sup-1 strains carrying distinctive chloroplast antibiotic resistance markers also show predominantly biparental chloroplast gene transmission. Chloroplast nucleoids of both parental origins (stained with the DNA-specific fluorochrome, DAPI) are retained in the zygotes homozygous for sup-1. The data are compatible with the idea that the sup-1 (suppressor of uniparental inheritance) locus may encode a chloroplast DNA nuclease that is expressed from both parental genomes. 相似文献
189.
Influence of phytoplankton on the response of bacterioplankton growth to nutrient enrichment 总被引:1,自引:0,他引:1
1. Laboratory experiments were conducted to test the effect of nutrient enrichment on bacterioplankton growth in the presence and absence of phytoplankton. 2. In one series of experiments, bacterioplankton growth in terms of specific activity [3H-thymidine incorporation (cell number)?1] was greater in whole lake water samples than in samples from which phytoplankton had been removed by filtration (1.0 μm), regardless of the nutrient enrichments (control, NH+4 plus PO3-4 and mannitol). Organic C enhanced bacterioplankton growth in both whole and filtered lake water. 3. In another series of experiments (with the same nutrient enrichments as in the first experiment except that glucose replaced mannitol), bacterioplankton growth in whole lake water enriched with PO3-4 plus NH+4 and incubated in the light was greater than in two treatments designed to inhibit photosynthetic activity (+DCMU and dark). Bacterioplankton response to nutrient addition was greatest in the PO3-4 plus NH+4 enrichment under all three conditions (light +DCMU, and dark). 4. These results indicate that bacterioplankton growth could be directly limited by inorganic P and N when these elements are in short supply. Enhancement of bacterioplankton growth by phytoplankton occurs only under PO3-4 and NH+4 replete environments. 相似文献
190.