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31.
32.
Summary The nucleotide sequence of cytoplasmic 5S ribosomal RNA fromEuglena gracilis has been determined to be: G- A C -G-U-A-C-G-G-C-C-A-U-A-C-U-A-C-C-G-G-G-A-A-U-A-C-A-C-C-U-G-A-A-C-C-C-G--U-C-G-A-U-U-U-C-A-G-A-A-G-U-U-A-A-G-C-C-G-G-G-U-U-A-G-G-C-C-C-A-G-U-U-A-G-U-A-C-U-G-A-G-U-G-G-G-C-G-A-C-C-A-C-U-U-G-G-G-A-A-C-A-C-U-G-G-G-U-G-C-U-G-U-A-C-G-C-U-Up. This RNA is 119 nucleotides long and the sequence of a probable tRNA-binding site is GAUU (position 41–44 from the 5-terminus), which is the same as that of a trypanosoma species,Crithidia fasci-culata. TheEuglena 5S rRNA has a pseudouridine residue at position 38 and 3-terminus is phosphorylated. The 5S rRNA sequence ofEuglena resembles those of several other protozoa and higher animals rather than plants.On leave from Department of Zoology, Hiroshima University, Hiroshima, Japan  相似文献   
33.
Based on the both of results for X-ray studies of tetrahydrothiazolopyridine derivative 1c and FXV673, we synthesized a series of thiazol-5-ylpyridine derivatives containing pyridine N-oxide and 2-carbamoylthiazole units to optimize the S4 binding element. N-Oxidation of thiazol-5-ylpyridine increased the anti-fXa activity more than 10-fold independent on the position of N-oxide. The 4-pyridine N-oxide derivatives 3a and 3d excelled over the tetrahydrothiazolopyridine 1b in potency. 2-Methylpyridine N-oxide 3d exhibited 49-fold selectivity over thrombin. Our modeling study proposed a binding mode that the pyridine N-oxide ring of 3a stuck into the "cation hole" , and the oxide anion of 3a occupied in the almost same space to that of FXV673. From observations of the SAR and modeling studies, we suggested the possibilities that the formation of hydrogen bond with the oxide anion in the "cation hole" and the affinity of cationic pyridine ring to S4 subsite were responsible for increase in anti-fXa activity.  相似文献   
34.
35.

Background

In 1996, Brazil became the first developing country to provide free and universal access to HAART. Although a decrease in overall mortality has been documented, there are no published data on the impact of HAART on causes of death among HIV-infected individuals in Brazil. We assessed temporal trends of mortality due to cardiovascular diseases (CVD), diabetes mellitus (DM) and other conditions generally not associated with HIV-infection among persons with and without HIV infection in Brazil between 1999 and 2004.

Methodology/Principal Findings

Odds ratios were used to compare causes of death in individuals who had HIV/AIDS listed on any field of the death certificate with those who did not. Logistic regression models were fitted with generalized estimating equations to account for spatial correlation; co-variables were added to the models to control for potential confounding. Of 5,856,056 deaths reported in Brazil between 1999 and 2004 67,249 (1.15%) had HIV/AIDS listed on the death certificate and non-HIV-related conditions were listed on 16.3% in 1999, increasing to 24.1% by 2004 (p<0.001). The adjusted average yearly increases were 8% and 0.8% for CVD (p<0.001), and 12% and 2.8% for DM (p<0.001), for those who had and did not have HIV/AIDS listed on the death certificate, respectively. Similar results were found for these conditions as underlying causes of death.

Conclusions/Significance

In Brazil between 1999 and 2004 conditions usually considered not to be related to HIV-infection appeared to become more likely causes of death over time than reported causes of death among individuals who had HIV/AIDS listed on the death certificate than in those who did not. This observation has important programmatic implications for developing countries that are scaling-up access to antiretroviral therapy.  相似文献   
36.
Buccal juice of the sea hare Aplysia juliana was found to degrade algal polysaccharides. The optimal enzyme composition for protoplast preparation from Undaria pinnatifida was protein at 48 μg/ml buccal juice from sea hare, 10 mg/ml cellulase Onozuka-RS, 0.4 M NaCl, 0.8 M sorbitol, 2 mg/ml dextran sulfate sodium salt, and 1 μl/ml 2-mercaptoethanol in 10 mM MES buffer (pH 6.0). Protoplasts of Eisenia bicyclis, Endarachne binghamiae (Phaeophyta), and Ulva pertusa (Chlorophyta) could also be prepared in a similar manner. Yields of these protoplasts were about 107 cells per gram of fresh weight alga. Received January 26, 1998; accepted September 17, 1998.  相似文献   
37.
The phylogenetic relationships of the Japanese Carabinae ground beetles were analyzed by comparing 1,069 nucleotide sequences in the mitochondrial gene encoding NADH dehydrogenase subunit 5 (ND5). The ND5 phylogenetic tree revealed that the hind-wingless Carabina and the hind-wingedCalosoma/Campalita (Calosomina) diverged from the common ancestor, andCychrus (Cychrini) is the outgroup of them. Five distinct clusters (groups) can be recognized in the Carabina, i.e.,CARABUS, HEMICARABUS, LEPTOCARABUS, APOTOMOPTERUS, andPROCRUSTES/DAMASTER. The ancestors of these lineages diverged almost at the same time more than 10 Myr ago. TheCarabus cluster includes two subclusters,Carabus andOhomopterus. Two species ofCarabus examined are phylogenetically rather remote, while five species amongOhomopterus are closely related to each other. The results suggest that diversification ofCarabus started much earlier than that ofOhomopterus, presumably in the Eurasian continent, and that ofOhomopterus in the Japanese archipelago. The branching order in theLEPTOCARABUS lineage was established,Authenocarabus/Pentacarabus being their outgroup. In theDAMASTER/PROCRUSTES lineage,Procrustes is placed as the outgroup ofDamaster, with the branching order ofCoptolabrus andAcoptolabrus/Damaster. The diversification of theDamaster subspecies appeared to have occurred in the Japanese archipelago earlier thanOhomopterus, and its phylogeny reflects their geographic distribution in the archipelago rather than the morphological characters.The nucleotide sequence data reported in this paper will appear in the GSDB, DDBJ, EMBL, and NCBI nucleotide sequence databases with the accession numbers D50339-D50365  相似文献   
38.
Summary The nucleotide sequences of 5S rRNAs from three protozoa,Bresslaua vorax, Euplotes woodruffi andChlamydomonas sp. have been determined and aligned together with the sequences of 12 protozoa species including unicellular green algae already reported by the authors and others. Using this alignment, a phylogenic tree of the 15 species of protozoa has been constructed. The tree suggests that the ancestor for protozoa evolved at an early time of eukaryotic evolution giving two major groups of organisms. One group, which shares a common ancestor with vascular plants, contains a unicellular green flagellate (Chlamydomonas) and unicellular green algae. The other group, which shares a common ancestor with the multicellular animals, includes various flagellated protozoa (includingEuglena), ciliated protozoa and slime molds. Most of these protozoa appear to have separated from one another at a fairly early period of eukaryotic evolution.  相似文献   
39.
Some molecular properties of the cytosolic and mitochondrial fumarases were compared. The carboxyl(C)-terminal amino acid of both the cytosolic and mitochondrial fumarases of rat liver cell was identified as leucine by using carboxypeptidase (CPase) A. As the amino(N)-terminal amino acid of both the cytosolic and mitochondrial fumarases could not be identified by the dansyl chloride method or by the cyanate method, the N-termini of these two fumarases seems to be masked. Both fumarases, after S-carboxymethylation, were completely digested with pronase E and CPase A and B, and the amino acids with blocked amino group were analyzed by high voltage paper electrophoresis and amino acid analysis after acid hydrolysis of these amino acid derivatives. The N-termini of the mitochondrial and cytosolic fumarases were identified as pyroglutamic acid and N-acetylalanine, respectively. To compare the primary structures of the two fumarases in detail, each fumarase was digested with an arginine-specific protease or cleaved with cyanogen bromide. The electrophoretic profiles of the digests of these fumarases were indistinguishable from each other.  相似文献   
40.
Summary The complete DNA sequence of theMicrococcus luteus spectinomycin (spc) operon and its adjacent regions has been determined. The sequence has revealed the presence of genes that are homologous to those of theEscherichia coli ribosomal and related proteins, L14, L24, L5, S8, L6, L18, S5, L30, L15, and secretion protein Y (secY), and the gene for adenylate kinase (adk). The gene arrangement in the spc operon is essentially the same as that ofE. coli except for the absence in theM. luteus spc operon of the genes for S14 and X protein that exist in theE. coli spc operon.SecY andadk seem to be composed of another operon (adk operon) with at least an open reading frame. The deduced amino acid sequences for these ribosomal proteins are well conserved among the two species (40–65% identity). Reflecting the high genomic guanine and cytosine (GC) content ofM. luteus (74%), the codon usage of the genes is extremely biased toward use of G and C, about 94% of the codon third positions being G or C. Seven codons, AUA, AAA, AGA, UUA, GUA, CUA, and CAA, all of which have A at the codon third positions, are completely absent in theM. luteus genes examined. Out of 11 genes in theM. luteus spc and adk operons, 5 (10) use GUG (UGA) and 6 (1) use AUG (UAA) as an initiation (termination) codon.  相似文献   
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