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1.
The DNA sequence composition of 526 dicot and 345 monocot intron sequences have been characterized using computational methods. Splice site information content and bulk intron and exon dinucleotide composition were determined. Positions 4 and 5 of 5 splice sites contain different statistically significant levels of information in the two groups. Basal levels of information in introns are higher in dicots than in monocots. Two dinucleotide groups, WW (AA, AU, UA, UU) and SS (CC, CG, GC, GG) have significantly different frequencies in exons and introns of the two plant groups. These results suggest that the mechanisms of splice-site recognition and binding may differ between dicot and monocot plants.  相似文献   
2.
Abstract

Several thiono triester containing oligonucleotide phosphorothioates linked with a lipophilic group have been synthesized. Some of these modified antisense oligonucleotides show potent anti-HCMV activity as well as improved cellular association and nuclease resistance.  相似文献   
3.
The emerging resistance to artemisinin derivatives that has been reported in South-East Asia led us to assess the efficacy of artemether-lumefantrine as the first line therapy for uncomplicated Plasmodium falciparum infections in Suriname. This drug assessment was performed according to the recommendations of the World Health Organization in 2011. The decreasing number of malaria cases in Suriname, which are currently limited to migrating populations and gold miners, precludes any conclusions on artemether efficacy because adequate numbers of patients with 28-day follow-up data are difficult to obtain. Therefore, a comparison of day 3 parasitaemia in a 2011 study and in a 2005/2006 study was used to detect the emergence of resistance to artemether. The prevalence of day 3 parasitaemia was assessed in a study in 2011 and was compared to that in a study in 2005/2006. The same protocol was used in both studies and artemether-lumefantrine was the study drug. Of 48 evaluable patients in 2011, 15 (31%) still had parasitaemia on day 3 compared to one (2%) out of 45 evaluable patients in 2005/2006. Overall, 11 evaluable patients in the 2011 study who were followed up until day 28 had negative slides and similar findings were obtained in all 38 evaluable patients in the 2005/2006 study. The significantly increased incidence of parasite persistence on day 3 may be an indication of emerging resistance to artemether.  相似文献   
4.
A cytomegalovirus (CMV) was isolated from its natural host, Peromyscus maniculatus, and was designated Peromyscus CMV (PCMV). A recombinant PCMV was constructed that contained Sin Nombre virus glycoprotein G1 (SNV-G1) fused in frame to the enhanced green fluorescent protein (EGFP) gene inserted into a site homologous to the human CMV UL33 (P33) gene. The recombinant CMV was used for expression and immunization of deer mice against SNV-G1. The results of the study indicate that P. maniculatus could be infected with as few as 10 virus particles of recombinant virus. Challenge of P. maniculatus with either recombinant or wild-type PCMV produced no overt pathology in infected animals. P. maniculatus immunized with recombinant virus developed an antibody response to SNV and EGFP. When rechallenged with recombinant virus, animals exhibited an anamnestic response against SNV. Interestingly, a preexisting immune response against PCMV did not prevent reinfection with recombinant PCMV.  相似文献   
5.
The major genes of the cariopsis aleurone layer colour in maize lines genotypes were studied in the check crossings with the samples analizators. The lines P 502 Rf M, F7 rf C, F2 rf C, Cg 10 rf M, and F 115 rf M have the following genotype on these genes: A1 A1 A2 A2 c1 c1 C2 C2 r r.  相似文献   
6.
7.
New model system of plastid transformation has been proposed using a wild representative of Solanaceae family--S. sinuata. Earlier obtained cybrid plants N. tabacum (+ S. sinuata) were used for transformation experiments by PEG treatment of protoplasts with aadA gene that confers resistance to spectinomycin. Transformed S. sinuata plastome was transferred from N. tabacum (+ S. sinuata) cybrid to S. sinuata wild type plants by somatic hybridization. Molecular analysis of nuclear and mitochondrial DNA has been performed.  相似文献   
8.
Secoiridoid glucosides from Fraxinus americana   总被引:1,自引:0,他引:1  
Investigation of the leaves of Fraxinus americana led to the isolation of five secoiridoid glucosides, demethylligstroside, (2"R)- and (2"S)-2"-hydroxyoleuropeins, fraxamoside and frameroside, together with 18 known compounds. Their structures were determined on the basis of spectroscopic studies and chemical evidence.  相似文献   
9.
Debates on patenting DNA must evolve to reflect the global decline in filings and regional disparities in patenting activity.  相似文献   
10.
Clustering techniques have been widely used in the analysis of microarray data to group genes with similar expression profiles. The similarity of expression profiles and hence the results of clustering greatly depend on how the data has been transformed. We present a method that uses the relative expression changes between pairs of conditions and an angular transformation to define the similarity of gene expression patterns. The pairwise comparisons of experimental conditions can be chosen to reflect the purpose of clustering allowing control the definition of similarity between genes. A variational Bayes mixture modeling approach is then used to find clusters within the transformed data. The purpose of microarray data analysis is often to locate groups genes showing particular patterns of expression change and within these groups to locate specific target genes that may warrant further experimental investigation. We show that the angular transformation maps data to a representation from which information, in terms of relative regulation changes, can be automatically mined. This information can be then be used to understand the "features" of expression change important to different clusters allowing potentially interesting clusters to be easily located. Finally, we show how the genes within a cluster can be visualized in terms of their expression pattern and intensity change, allowing potential target genes to be highlighted within the clusters of interest.  相似文献   
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