排序方式: 共有36条查询结果,搜索用时 15 毫秒
1.
Shahid Mudassir Baba Aga Syed Sameer Mushtaq A. Siddiqi 《Indian journal of human genetics》2013,19(3):360-362
Primary amenorrhea is one of the common reproductive disorder affecting females. It leads to the absence of menarche in the reproductive age group in females and/or complete absence of reproductive organs. There are many causes which lead to PA, including genetic aberrations which are the leading factors. 相似文献
2.
Genetic diversity within the forest Coffea arabica L. gene pool in Ethiopia has not been extensively examined with molecular markers. In the present study, a total of 75 polymorphic RAPD bands generated by twelve random primers were used to assess genetic diversity among 144 genotypes representing 16 C. arabica populations. The number of polymorphic bands detected with each primer ranged from 2 to 9 with a mean of 6.25 bands per primer. Banding patterns ranged in percentage polymorphism from 37% to 73% with an overall mean of 56% for the populations analyzed. The amount of genetic variation among populations estimated by Shannon-Weaver diversity index was (H = 0.30). The within population and between populations differentiation values were 0.65 and 0.35, respectively. Genetic differentiations within and between zones of sample collection sites were 0.80 and 0.20, respectively. Within population average similarities estimated by simple matching coefficients ranged from 0.72 to 0.85, with an overall average of 0.78. In the cluster analysis that used individual samples as operational taxonomic units, most of the representatives of the same population failed to cluster before they joined members of other populations. Nevertheless, most of the populations were clustered on the basis of their geographic closeness and an east west differentiation was observed at approximately 75% similarity. The results obtained provide information on how to select sites for in situ conservation of C. arabica germplasm. 相似文献
3.
4.
Watanabe H Nishimoto T Aga H Kubota M Fukuda S Kurimoto M Tsujisaka Y 《Carbohydrate research》2005,340(9):1577-1582
A novel cyclic pentasaccharide (CPS) and a branched cyclic pentasaccharide (6G-CPS) consisting of d-glucopyranose were synthesized with 6-alpha-glucosyltransferase (6GT) and 3-alpha-isomaltosyltransferase (IMT) from Bacillus globisporus N75. The structure of CPS was cyclo-[-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->]. The other, 6G-CPS, had the structure cyclo-[-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->3)-[alpha-D-Glcp-(1-->6)]-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->]. The formation of CPS was presumed to occur after the following four successive reactions: a 6-glucosyltransfer reaction with 6GT, a 4-glucosyltransfer reaction with 6GT, a 3-isomaltosyltransfer reaction with IMT, and a cyclization reaction with IMT. 相似文献
5.
Formation of N-Ethylmaleimide (NEM)-Glutathione Conjugate and N-Ethylmaleamic Acid Revealed by Mass Spectral Characterization of Intracellular and Extracellular Microbial Metabolites of NEM
下载免费PDF全文
![点击此处可从《Applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The extracellular and intracellular metabolites formed upon exposure of activated sludge microorganisms to a sublethal concentration of N-ethylmaleimide were monitored by liquid chromatography with ion trap mass spectrometry. The metabolite N-ethylsuccinimido-S-glutathione (m/z 433) was converted rapidly to N-(2-oxoethyl)-2,2-(propionylamino)propanamide (m/z 187) and N-ethylmaleamic acid (m/z 144). 相似文献
6.
Folate being an important vitamin of B Complex group in our diet plays an important role not only in the synthesis of DNA but also in the maintenance of methylation reactions in the cells. Folate metabolism is influenced by several processes especially its dietary intake and the polymorphisms of the associated genes involved. Aberrant folate metabolism, therefore, affects both methylation as well as the DNA synthesis processes, both of which have been implicated in the development of various diseases. This paper reviews the current knowledge of the processes involved in folate metabolism and consequences of deviant folate metabolism, particular emphasis is given to the polymorphic genes which have been implicated in the development of various diseases in humans, like vascular diseases, Down's syndrome, neural tube defects, psychiatric disorders and cancers. 相似文献
7.
8.
Evidence for nucleotide receptor modulation of cross talk between MAP kinase and NF-kappa B signaling pathways in murine RAW 264.7 macrophages 总被引:5,自引:0,他引:5
Aga M Watters JJ Pfeiffer ZA Wiepz GJ Sommer JA Bertics PJ 《American journal of physiology. Cell physiology》2004,286(4):C923-C930
Extracellular nucleotides such as ATP are present in abundance at sites of inflammation and tissue damage, and these agents exert a potent modulatory effect on macrophage/monocyte function via the nucleotide receptor P2X7. In this regard, after exposure to bacterial LPS, P2X7 activation augments expression of the inducible nitric oxide (NO) synthase and production of NO in macrophages. Because P2X7 has been reported to stimulate certain members of the MAP kinase family (ERK1/2) and can enhance the DNA-binding activity of NF-B, we tested the hypothesis that LPS and nucleotides regulate NF-B-dependent inflammatory events via cross talk with MAPK-associated pathways. In this regard, the present studies revealed that cotreatment of macrophages with LPS and the P2X7-selective ligand 2'-3'-O-(4-benzoylbenzoyl)adenosine 5'-triphosphate (BzATP) results in the cooperative activation of NF-B DNA-binding activity and a sustained attenuation of levels of the NF-B inhibitory protein IB. Interestingly, a persistent reduction in IB levels is also observed when the MEK1/2 inhibitor U0126 is coadministered with LPS, suggesting that components of the MEK/ERK pathway are involved in regulating IB protein expression and/or turnover. The observation that U0126 and BzATP exhibit overlapping actions with respect to LPS-induced changes in IB levels is supported by the finding that Ras activation, which is upstream of MEK/ERK activation, is reduced upon macrophage cotreatment with BzATP and LPS compared with the effects of BzATP treatment alone. These data are consistent with the concept that the Ras/MEK/ERK pathways are involved in regulating NF-B/IB-dependent inflammatory mediator production and suggest a previously unidentified mechanism by which nucleotides can modulate LPS-induced action via cross talk between NF-B and Ras/MEK/MAPK-associated pathways. nucleotide receptors; mitogen-activated protein kinases; nuclear factor-B; monocytes/macrophages; cytokines 相似文献
9.
Inter-simple sequence repeat (ISSR) variation in forest coffee trees (Coffea arabica L.) populations from Ethiopia 总被引:1,自引:0,他引:1
Genetic variation of forest coffee trees (Coffea arabica L.) from four regions of Ethiopia was investigated using inter-simple sequence repeat (ISSR) markers. A total of 160 individuals
representing 16 populations were sampled. Eleven ISSR primers amplified a total of 123 fragments of which 31 fragments (25%)
were polymorphic. Estimate of total gene diversity (H
T), and the coefficient of genetic differentiation (G
ST) were 0.37 and 0.81, respectively. This indicates that most of the variability is between populations than within populations.
The partitioning of genetic variation into within and between populations based on Shannon’s information index also revealed
more differentiation between populations (0.80) than within populations (0.20). In the phenogram most of the coffee tree samples
were clustered on the basis of their regions of origin but failed to cluster according to their respective populations, which
could be attributed to the presence of substantial gene flow between adjacent populations in each region assisted by man in
the process of transplantation or by wild animals such as monkeys, which eat the berries and defecate the seeds elsewhere.
On the other hand, the inter-regional clustering of some coffee tree samples from Bale and Jimma regions could be due to the
transport of coffee seeds across regions and their subsequent planting. Although ISSR markers detected lower polymorphic loci
than previously reported results with random amplified polymorphic DNA (RAPD) markers on the same materials, it can be used
as an alternative method for molecular characterization of C. arabica populations. The results may provide information to select sites for in situ conservation. 相似文献
10.
Minor flavonoids from licorice 总被引:4,自引:0,他引:4
Three minor flavonoids, licofuranocoumarin, isotrifoliol and glisoflavanone, were isolated from licorice (underground part of Glycyrrhiza uralensis), and their structures with 3-arylcoumarin, coumestan and isoflavanone skeletons were respectively elucidated on the basis of spectroscopic data. 相似文献