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1.
The possibility of obtaining low-molecular-weight heparins using a chitinolytic enzymatic complex immobilized on Silochrom has been demonstrated. The optimal conditions of this process (sodium acetate buffer, pH 7.0–7.5; temperature, 40–45°C; and duration of hydrolysis, 3 h) were determined. Depending on the ratio between heparin and the immobilized enzymatic complex, samples with molecular weights varying from 1.7 to 4.7 kDa, were obtained. These complexes inhibited factor Xa 2.0–3.7 times more effectively than the original heparin.  相似文献   
2.
The shape of the resting eggs of a large branchiopod crustacean, the Anostraca Tanymastix stagnalis , is represented very accurately by analytical expressions. The occurrence of atypical shape of some T. stagnalis eggs may be viewed as a simple change of the analytical expression describing the usual egg shape. Their unusual shape may be explained by a higher embryo volume within an envelope of a given size. Biological implications are briefly discussed and hypothesized in an evolutionary point of view.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 55–60.  相似文献   
3.
Abstract.
  • 1 The structure of local populations of a monophagous butterfly, the bog fritillary Proclossiana eunomia, was studied in a complex of suitable habitat patches separated by spruce plantations or fertilized pasture.
  • 2 An unexpected high level of adult movements between habitat patches was detected by a mark—release—recapture technique. Local populations were connected by adult movements across unsuitable habitats, leading to a meta-population structure.
  • 3 This evidence of the metapopulation structure of a specialist butterfly challenges the supposed relationship between habitat specialization and closed, isolated populations.
  • 4 Males and females of P.eunomia exhibited different spatial behaviours; females were more likely to emigrate and dispersed further than males. These differences in spatial behaviour are related to the mating system.
  相似文献   
4.
New microbial genomes are sequenced at a high pace, allowing insight into the genetics of not only cultured microbes, but a wide range of metagenomic collections such as the human microbiome. To understand the deluge of genomic data we face, computational approaches for gene functional annotation are invaluable. We introduce a novel model for computational annotation that refines two established concepts: annotation based on homology and annotation based on phyletic profiling. The phyletic profiling-based model that includes both inferred orthologs and paralogs—homologs separated by a speciation and a duplication event, respectively—provides more annotations at the same average Precision than the model that includes only inferred orthologs. For experimental validation, we selected 38 poorly annotated Escherichia coli genes for which the model assigned one of three GO terms with high confidence: involvement in DNA repair, protein translation, or cell wall synthesis. Results of antibiotic stress survival assays on E. coli knockout mutants showed high agreement with our model''s estimates of accuracy: out of 38 predictions obtained at the reported Precision of 60%, we confirmed 25 predictions, indicating that our confidence estimates can be used to make informed decisions on experimental validation. Our work will contribute to making experimental validation of computational predictions more approachable, both in cost and time. Our predictions for 998 prokaryotic genomes include ∼400000 specific annotations with the estimated Precision of 90%, ∼19000 of which are highly specific—e.g. “penicillin binding,” “tRNA aminoacylation for protein translation,” or “pathogenesis”—and are freely available at http://gorbi.irb.hr/.  相似文献   
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6.
Plasma Physics Reports - Inactivation of spore microorganisms on a dielectric surface by a dielectric barrier discharge with plane electrodes was studied experimentally. It is shown that, at an...  相似文献   
7.
Eight tetranucleotide microsatellite loci were isolated from the haplochromine cichlid fish, Pseudocrenilabrus multicolor victoriae, an important model species for studies in respiratory ecology, conservation, and evolution. We surveyed variation at these loci in 23 individuals from western Uganda, finding four to 19 alleles per locus and an average expected heterozygosity of 0.8575. These microsatellite loci will be used to examine gene flow and population structure in Ugandan P. m. victoriae.  相似文献   
8.
Panov  V. P.  Safonova  S. S.  Baidarov  I. V. 《Biology Bulletin》2022,49(5):498-511
Biology Bulletin - The features of the structural adaptive changes in the somatic muscles of rainbow trout are presented at various stages of early post-hatching ontogenesis. The development of the...  相似文献   
9.
Panov  V. P.  Falii  S. S.  Orlov  A. M.  Artemenkov  D. V. 《Journal of Ichthyology》2019,59(6):928-937
Journal of Ichthyology - The morphological and functional characteristics of the somatic musculature’s histological structure have been studied for three species of deep-sea fish from the...  相似文献   
10.
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