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21.
This article is a taxonomic study of the radiolarian species of the superfamilies Eptingiacea and Saturnaliacea occurring in the middle Carnian fauna from the Köseyahya section, near the town of Elbistan, southeastern Turkey. This fauna is characteristic of the Tetraporobrachia haeckeli Radiolarian Zone as defined in Austria and later found also in Turkey and Oman. It comes from an 8 m thick succession of clayey/cherty limestones from the lower part of the section. In addition, a few species from the late Ladinian and Carnian from Oman and the early Norian from Alaska have also been included in this study, in order to improve some generic diagnoses and to show the diversity and evolutionary trends of some genera. 32 radiolarian species of which 22 are new are described and illustrated, and assigned to 16 genera of which three are new (Capnuchospyris, Veleptingium, and Triassolaguncula). The diagnoses of some species, genera, subfamilies and families have been revised, and the family Eptingiidae has been raised to the rank of superfamily.  相似文献   
22.

Introduction  

Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology.  相似文献   
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Magnetic poly(ethylene glycol dimethacrylate-N-methacryloyl-(L)-histidine methyl ester) [mag-poly(EGDMA-MAH) beads, 50-100 microm in diameter, were produced by suspension polymerization for affinity depletion of immunoglobulin G (IgG) from human serum. Cu2+ ions were complexed directly via MAH groups (Cu2+ loading: 4.1 micromol/g). IgG depletion studies were performed by magnetically stabilized fluidized bed column. Acetate, Tris-HCl, MES and phosphate buffers all allow adsorption of similar quantities of IgG (27.3-45.6 mg/g). MOPS and HEPES allow higher adsorption quantities (79.6 mg/g and 74.1mg/g, respectively). Maximum adsorption capacities in MOPS buffer were 46.8 mg/g for mag-poly(EGDMA-MAH) and 102.1mg/g for Cu2+ chelated mag-poly(EGDMA-MAH) beads. The adsorption capacity decreased drastically from 102.1mg/g to 30.7 mg/g with the increase of the flow rate from 0.2 ml/min to 3.5 ml/min. The elution studies were performed by 1.0M NaCl. The elution results demonstrated that the adsorption of IgG to the adsorbent was reversible. To test the efficiency of IgG depletion from human serum, proteins in the serum and eluted portion were analyzed by two-dimensional gel electrophoresis. The depletion efficiency for IgG was above 99.4%. Eluted proteins include mainly IgG, and a small number of non-albumin proteins such as apo-lipoprotein A1, sero-transferrin, haptoglobulin and alpha1-antitrypsin. When anti-HSA-sepharose adsorbent is used together with our metal-chelated mag-beads, IgG and HSA can be depleted in a single step.  相似文献   
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Acetic acid hydrazide containing 5-methyl-2-benzoxazolinone (4) was synthesized by the condensation of 2-(5-methyl-2-benzoxazolinone-3-yl)acetate with hydrazine hydrate. Thiosemicarbazide derivatives (5a-5d) were afforded by the reaction of corresponding compound 4 with substituted isothiocyanates. The cyclization of compounds 5a-5d in the presence of triethylamine resulted in the formation of compounds 6a-6d containing 1,2,4-triazole ring. On the other hand, the treatment of compounds 5a-5d with orthophosphoric acid caused the conversion of side chain of compounds 5a-5d into 1,3,4-thiadiazole ring: thus, compounds 7a-7c were obtained. The treatment of compound 4 with aromatic aldehydes resulted in the formation of arylidene hydrazides as cis-trans conformers (8a-8e). The structures of the compounds were elucidated by spectral and elemental analysis. While most compounds were exhibiting high activity in the analgesic-anti-inflammatory field, most of them were found to be inactive against bacteria and fungi.  相似文献   
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We describe an analysis, applicable to any spotted microarray dataset produced using genomic DNA as a reference, that quantifies prokaryotic levels of mRNA on a genome-wide scale. Applying this to Mycobacterium tuberculosis, we validate the technique, show a correlation between level of expression and biological importance, define the complement of invariant genes and analyze absolute levels of expression by functional class to develop ways of understanding an organism's biology without comparison to another growth condition.  相似文献   
27.

Background

The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comParative analyses. In comParative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (a basal eudicot). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution of simple sequence repeats (SSRs) and longer dispersed repeats (SDR), and patterns of nucleotide composition.

Results

The Nuphar [GenBank:NC_008788] and Ranunculus [GenBank:NC_008796] plastid genomes share characteristics of gene content and organization with many other chloroplast genomes. Like other plastid genomes, these genomes are A+T-rich, except for rRNA and tRNA genes. Detailed comparisons of Nuphar with Nymphaea, another Nymphaeaceae, show that more than two-thirds of these genomes exhibit at least 95% sequence identity and that most SSRs are shared. In broader comparisons, SSRs vary among genomes in s of abundance and length and most contain repeat motifs based on A and T nucleotides.

Conclusion

SSR and SDR abundance varies by genome and, for SSRs, is proportional to genome size. Long SDRs are rare in the genomes assessed. SSRs occur less frequently than predicted and, although the majority of the repeat motifs do include A and T nucleotides, the A+T bias in SSRs is less than that predicted from the underlying genomic nucleotide composition. In codon usage third positions show an A+T bias, however variation in codon usage does not correlate with differences in A+T-richness. Thus, although plastome nucleotide composition shows "A+T richness", an A+T bias is not apparent upon more in-depth analysis, at least in these aspects. The pattern of evolution in the sequences identified as ycf15 and ycf68 is not consistent with them being protein-coding genes. In fact, these regions show no evidence of sequence conservation beyond what is normal for non-coding regions of the IR.  相似文献   
28.
Morning- and evening-type individuals differ on a number of psychological and biological variables. There has been increasing interest in the relationship between chronotype and personality traits. The aim of this study was to investigate the relationship between impulsivity and chronotype in suicide attempters. Eighty-nine suicide attempters were included in the study, and systematic information on suicide attempts was recorded. The Morningness-Eveningness Questionnaire was applied to determine chronotype, and attempter impulsivity was measured by the total score of the Barratt Impulsiveness Scale. Significant differences between chronotype and impulsivity scores were found. Evening-type subjects reported significantly higher impulsivity scores than both neither- and morning-types. A significant association between chronotype and type of suicide attempt was detected. The largest proportion of violent suicide attempters were evening-type subjects. Violent suicide attempters also reported significantly higher impulsivity scores than nonviolent attempters. Previous studies have pointed out possible relations between eveningness and impulsivity. Current findings suggest that eveningness may be a risk factor for violent suicide attempts by increasing impulsivity.  相似文献   
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