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Plant and Soil - Root morphological response to localised phosphorus (P) application plays a crucial role in P acquisition. However, detailed knowledge of when and where roots respond to P patch... 相似文献
133.
Structural variants have a considerable impact on human genomic diversity. However, their evolutionary history remains mostly unexplored. Here, we developed a new method to identify potentially adaptive structural variants based on a similarity-based analysis that incorporates genotype frequency data from 26 populations simultaneously. Using this method, we analyzed 57,629 structural variants and identified 576 structural variants that show unusual population differentiation. Of these putatively adaptive structural variants, we further showed that 24 variants are multiallelic and overlap with coding sequences, and 20 variants are significantly associated with GWAS traits. Closer inspection of the haplotypic variation associated with these putatively adaptive and functional structural variants reveals deviations from neutral expectations due to: 1) population differentiation of rapidly evolving multiallelic variants, 2) incomplete sweeps, and 3) recent population-specific negative selection. Overall, our study provides new methodological insights, documents hundreds of putatively adaptive variants, and introduces evolutionary models that may better explain the complex evolution of structural variants. 相似文献
134.
Yutaka Tokiwa Masaru Kitagawa Hong Fan Tetsuji Yokochi Takao Raku Yoichi Hiraguri Shigeo Shibatani Yoshihiko Maekawa Naoki Kashimura Ryuichiro Kurane 《Biotechnology Techniques》1999,13(8):563-566
The transesterification of divinyladipate with adenosine in DMF containing 20% (v/v) DMSO was catalyzed by Streptomyces sp. alkaline protease and esterification occurred exclusively at the 3-position of hydroxyl group of ribofuranose in adenosine to give 3-O-vinyladipoyl adenosine without other products. 相似文献
135.
The morphological development of genital ducts both intra-gonadal (ovarian cavity and efferent duct) and extra-gonadal (oviduct and sperm duct) was investigated in a model teleost, medaka Oryzias latipes. The results showed that the extra-gonadal genital ducts contained two structural units, the anterior and posterior parts, in both sexes. Of special interest is a newly discovered process for the development of a posterior part of the oviduct. The anterior part of oviduct extended continuously from the ovarian cavity at the posterior end of the ovary. Then the posterior part of oviduct, which termed genital pore lip (GPL) in this study, was formed. This part results from invagination and cavitation of the cortex of urinogenital papillae (UGP) and forms the wall of the oviduct opening. We also suggest that the ventral region of urethra mesenchyme has an important role in extra-genital ducts formation. 相似文献
136.
Local delivery of soluble TNF-alpha receptor 1 gene reduces infarct size following ischemia/reperfusion injury in rats 总被引:14,自引:0,他引:14
Sugano M Hata T Tsuchida K Suematsu N Oyama J Satoh S Makino N 《Molecular and cellular biochemistry》2004,266(1-2):127-132
Apoptosis in the myocardium is linked to ischemia/reperfusion injury, and TNF-alpha induces apoptosis in cardiomyocytes. A significant amount of TNF-alpha is detected after ischemia and reperfusion. Soluble TNF-alpha receptor 1 (sTNFR1) is an extracellular domain of TNF-alpha receptor 1 and is an antagonist to TNF-alpha. In the present study, we examined the effects of sTNFR1 on infarct size in acute myocardial infarction (AMI) following ischemia/reperfusion. Male Wistar rats were subjected to left coronary artery (LCA) ligation. After 30 min of LCA occlusion, the temporary ligature on the LCA was released and blood flow was restored. Immediately after reperfusion, a total of 200 microg of sTNFR1 or LacZ plasmid was injected into three different sites of the left ventricular wall. At 6 h, 1 and 2 days after reperfusion, the TNF-alpha bioactivity in the myocardium was significantly higher in rats receiving LacZ plasmid than in sham-operated rats, whereas sTNFR1 plasmid significantly suppressed the increase in the TNF-alpha bioactivity. The sTNFR1 plasmid significantly reduced DNA fragmentation and caspase activity compared to the LacZ plasmid. Finally, the sTNFR1 expression-plasmid treatment significantly reduced the area of myocardial infarction at 2 days after ischemia/reperfusion compared to LacZ plasmid. In conclusion, the TNF-alpha bioactivity in the heart increased from the early stage of ischemia/reperfusion, and this increase was thought to contribute in part to the increased area of myocardial infarction. Suppression of TNF-alpha bioactivity with the sTNFR1 plasmid reduced the infarct size in AMI following ischemia and reperfusion. 相似文献
137.
Yumoto I Hirota K Iwata H Akutsu M Kusumoto K Morita N Ezura Y Okuyama H Matsuyama H 《Archives of microbiology》2004,181(5):345-351
A facultative psychrophilic bacterium, strain L-2, that grows at 0 and 5°C as minimum growth temperatures in complex and defined media, respectively, was isolated. On the basis of taxonomic studies, strain L-2 was identified as Cobetia marina. The adaptability of strain L-2 to cold temperature was higher than that of the type strain and of other reported strains of the same species. When the bacterium was grown at 5–15°C in a defined medium, it produced a high amount of trans-unsaturated fatty acids. By contrast, in a complex medium in the same temperature range it produced a low amount of trans-unsaturated fatty acids. In the complex medium at 5°C, the bacterium exhibited a three-fold higher growth rate than that obtained in the defined medium. Following a temperature shift from 11 to 5°C, strain L-2 grew better in complex than in defined medium. Furthermore, when the growth temperature was shifted from 0 to 5°C both the growth rate and the yield of strain L-2 growing in complex medium was markedly enhanced. These phenomena suggest that an upshift of the growth temperature had a positive effect on metabolism. The effects of adding complex medium components to the defined medium on bacterial growth rate and fatty acid composition at 5°C were also studied. The addition of yeast extract followed by peptone was effective in promoting rapid growth, while glutamate addition was less effective, resulting in a cis-unsaturated fatty acid ratio similar to that of cells grown in the complex medium. These results suggest that the rapid growth of strain L-2 at low temperatures requires a high content of various amino acids rather than the presence of a high ratio of cis-unsaturated fatty acids in the cell membrane. 相似文献
138.
Attachment of oligonucleotide probes to poly carbodiimide-coated glass for microarray applications 总被引:3,自引:0,他引:3
Oligonucleotide-based DNA microarrays are becoming increasingly useful tools for the analysis of gene expression and single nucleotide polymorphisms (SNPs). Here, we present a method that permits the manufacture of microarrays from non-modified oligonucleotides on a poly carbodiimide-coated glass surface by UV-irradiation. The use of UV-irradiation facilitates an increase in the level of signal intensity, but it does not affect signal discrimination by the oligonucleotides immobilized on the surface. The signal intensity obtained for an array fabricated using non-modified oligonucleotides with UV-irradiation is ~7-fold greater than that without UV-irradiation. The detection of SNPs was tested to ascertain whether this technique could discriminate specific hybridization signals without causing significant UV-irradiation-induced damage to the immobilized oligonucleotides. We found that this immobilization method provides greater hybridization signals and a better match/mismatch ratio of SNPs than do the established aminosilane techniques. Application of this technology to manufacturing DNA microarrays for sequence analysis is discussed. 相似文献
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