排序方式: 共有53条查询结果,搜索用时 15 毫秒
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应用RTPCR技术从中国人胎肝细胞中分离出1个566bp大小的基因片段,经过克隆、限制性内切酶鉴定和序列分析证实为TPO的cDNA片段.与GenBank中发表的人TPOmRNA的序列比较同源性在82%~99%之间,仅有2个碱基不相同,在175位密码子(523~525位的碱基)分别是CGG和CAA,即精氨酸(R)的位置上,中国人是谷胺酰氨(G).而与测得的韩国人序列比较,在相应位置的氨基酸是相同的 相似文献
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Boxma B de Graaf RM van der Staay GW van Alen TA Ricard G Gabaldón T van Hoek AH Moon-van der Staay SY Koopman WJ van Hellemond JJ Tielens AG Friedrich T Veenhuis M Huynen MA Hackstein JH 《Nature》2005,434(7029):74-79
Hydrogenosomes are organelles that produce ATP and hydrogen, and are found in various unrelated eukaryotes, such as anaerobic flagellates, chytridiomycete fungi and ciliates. Although all of these organelles generate hydrogen, the hydrogenosomes from these organisms are structurally and metabolically quite different, just like mitochondria where large differences also exist. These differences have led to a continuing debate about the evolutionary origin of hydrogenosomes. Here we show that the hydrogenosomes of the anaerobic ciliate Nyctotherus ovalis, which thrives in the hindgut of cockroaches, have retained a rudimentary genome encoding components of a mitochondrial electron transport chain. Phylogenetic analyses reveal that those proteins cluster with their homologues from aerobic ciliates. In addition, several nucleus-encoded components of the mitochondrial proteome, such as pyruvate dehydrogenase and complex II, were identified. The N. ovalis hydrogenosome is sensitive to inhibitors of mitochondrial complex I and produces succinate as a major metabolic end product--biochemical traits typical of anaerobic mitochondria. The production of hydrogen, together with the presence of a genome encoding respiratory chain components, and biochemical features characteristic of anaerobic mitochondria, identify the N. ovalis organelle as a missing link between mitochondria and hydrogenosomes. 相似文献
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Progress in quantitative analysis of plant hormones 总被引:1,自引:0,他引:1
FU JiHong SUN XiaoHong WANG JiDe CHU JinFang & YAN CunYu College of Chemistry Chemical Engineering Xinjiang University Urumqi China National Centre for Plant Gene Research 《科学通报(英文版)》2011,(Z1):355-366
Plant hormones are small molecular natural products that regulate all plant developmental processes at low concentrations. Quantitative analysis of plant hormones is increasingly important for in-depth study of their biosynthesis,transport,metabolism and molecular regulatory mechanisms. Although plant hormone analysis remains a bottleneck in plant scientific research owing to the trace concentrations and complex components in plant crude extracts,much progress has been achieved in the development of extraction,purification and detection techniques in recent years. Solid phase extraction and chromatography/mass spectrometry have been applied widely for purification and quantitative analysis of plant hormones owing to their high selectivity and sensitivity. Purification methods such as liquid partition and immunoaffinity chromatography,and detection methods including immunoassay and electrochemical analysis,are employed. The advantages and disadvantages of these methods are discussed. In situ,real-time and multi-plant hormone profiling will comprise mainstream techniques for quantitative analyses in future studies on the regulatory mechanisms and crosstalk of plant hormones. 相似文献
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Richard Yeo 《Annals of science》2018,75(2):73-96
Among the elements of the modern scientific ethos, as identified by R.K. Merton and others, is the commitment of individual effort to a long-term inquiry that may not bring substantial results in a lifetime. The challenge this presents was encapsulated in the aphorism of the ancient Greek physician, Hippocrates of Kos: vita brevis, ars longa (life is short, art is long). This article explores how this complaint was answered in the early modern period by Francis Bacon’s call for the inauguration of the sciences over several generations, thereby imagining a succession of lives added together over time. However, Bacon also explored another response to Hippocrates: the devotion of a ‘whole life’, whether brief or long, to science. The endorsement of long-term inquiry in combination with intensive lifetime involvement was embraced by some leading Fellows of the Royal Society, such as Robert Boyle and Robert Hooke. The problem for individuals, however, was to find satisfaction in science despite concerns, in some fields, that current observations and experiments would not yield material able to be extended by future investigations. 相似文献
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Gene R. Wilde 《西北部美国博物学家》2011,49(2)
White River springfish collected in August and December 1966 from Hot Creek Spring, Nevada, fed primarily on amphipods, ostracods, plant fragments, and detritus. Compostition of the diet was similar in both months. However, amphipods were the most important food in August, while in December amphipods, ostacods, plant fragments, and detritus were of approximately equal importance. Comparison of diel feeding periodicity and activity patterns suggests that most of the daily activity of White River springfish is related to feeding. 相似文献