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41.
Analysis of clinical material obtained from the individuals (49 psoriasis patients and 357 individuals without this disease) representing three ethnic populations of Dagestan (Avars, Dargins, and Kumyks) was performed. Polymorphism of the blood group loci AB0, Rhesus (RH), Kell, P, and Lewis, as well as of the protein-encoding loci for haptoglobin (HP), group-specific component (GC), and the enzymes, including glycosylase (GL01), esterase D (ESD), 6-phosphate dehydrogenase (6PDG), and acid phosphatase (ACP), was studied. It was demonstrated that in the pooled sample of Avars and Kumyks the Lewis system phenotype Le(a-b-) and the RH homozygotes (ee/ee) were statistically significantly more frequent among the psoriasis patients (P = 0.0488 and P = 0.0166, respectively), than among healthy controls of the same ethnic groups. It was suggested that for the pooled sample of Avars and Kumyks, homozygosity for the recessive RH allele (ee/ee) in combination with the Le(a-b-) phenotype, representing homozygosity for recessive allele le, was the risk factor for the development of psoriasis.  相似文献   
42.
Polymorphism of fragments of the ND1 and CO1 mitochondrial genes was for the first time found in four liver fluke Fasciola hepatica samples from Ukraine, Belarus, Moscow region, and Mordovia. The ND1 and CO1 fragments were respectively 292 and 433 bp in size, with polymorphic sites accounting for 2.7 and 0.9% of the total sequence. Seven haplotypes were found in the four samples; two haplotypes (A and B) were most common (29.1 and 45.8%, respectively) in the pooled sample. The haplotype frequency distribution differed among the four populations. Haplotype B prevailed in the Mordovian and Moscow region samples. In addition, these samples had a higher number of unique haplotypes (A2, A3, B2). The results testify to genetic divergence of the four geographically distant populations of F. hepatica.  相似文献   
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A new enzyme preparation of fungal pectin lyase (EC 4.2.2.10) was shown to be useful for the production of cranberry juice and clarification of apple juice in the food industry. A comparative study showed that the preparation of pectin lyase is competitive with commercial pectinase products. The molecular weight of homogeneous pectin lyase was 38 kDa. Properties of the homogeneous enzyme were studied. This enzyme was most efficient in removing highly esterified pectin.  相似文献   
45.
Selenocysteine incorporation in eukaryotes occurs cotranslationally at UGA codons via the interactions of RNA-protein complexes, one comprised of selenocysteyl (Sec)-tRNA([Ser]Sec) and its specific elongation factor, EFsec, and another consisting of the SECIS element and SECIS binding protein, SBP2. Other factors implicated in this pathway include two selenophosphate synthetases, SPS1 and SPS2, ribosomal protein L30, and two factors identified as binding tRNA([Ser]Sec), termed soluble liver antigen/liver protein (SLA/LP) and SECp43. We report that SLA/LP and SPS1 interact in vitro and in vivo and that SECp43 cotransfection increases this interaction and redistributes all three proteins to a predominantly nuclear localization. We further show that SECp43 interacts with the selenocysteyl-tRNA([Ser]Sec)-EFsec complex in vitro, and SECp43 coexpression promotes interaction between EFsec and SBP2 in vivo. Additionally, SECp43 increases selenocysteine incorporation and selenoprotein mRNA levels, the latter presumably due to circumvention of nonsense-mediated decay. Thus, SECp43 emerges as a key player in orchestrating the interactions and localization of the other factors involved in selenoprotein biosynthesis. Finally, our studies delineating the multiple, coordinated protein-nucleic acid interactions between SECp43 and the previously described selenoprotein cotranslational factors resulted in a model of selenocysteine biosynthesis and incorporation dependent upon both cytoplasmic and nuclear supramolecular complexes.  相似文献   
46.
New bryozoans from the Middle-Upper Devonian (Eifelian-Frasnian) and the Lower Carboniferous (Tournaisian) of the Holy Cross Mountains in central Poland are described: Bigeyella sparsa gen. et sp. nov., B. separata gen. et sp. nov., Eridopora singula sp. nov., Leptotrypa pulchra sp. nov., Kysylschinipora klarae sp. nov., Coelotubulipora rara sp. nov., Alternifenestella genuina sp. nov., Exfenestella polonica sp. nov., and Rectifenestella localis sp. nov. Some paleogeographic and stratigraphic aspects of the Paleozoic deposits of this region are discussed and main bryozoan localities are described.  相似文献   
47.
Commercial and pilot pectate lyase preparations (EC 4.2.2.2) have been compared. They differ in their effect on pectins with different esterification degrees (ED). The activity of the pilot preparation with respect to a substrate with ED = 70% is tenfold lower than with respect to unesterified polygalacturonic acid. For commercial preparations, this activity ratio ranged within 1.5–2. At equal pectate lyase activities, the commercial preparations better remove pectin from crude cotton fabric during its boil off. The laboratory preparation is more efficient for improving the capillarity (wettability) of the fabric owing to the cooperative effect of the pectate lyase, cellulase, and hemicellulase present in the preparation.  相似文献   
48.
Electroconductive interpolymer polyaniline complexes are synthesized on the DNA matrix, using the method of oxidative polymerization of aniline with two different biocatalyzers: horseradish root peroxidase and micropiroxidase-11 biomimetic. The spectral characteristics and morphology of the acquired biocomposites have been studied. The stereospecificity of the acquired samples of interpolymer complexes is shown, depending on the biocatalyzers used. The results acquired indicate the important role of a biocatalyzer in the formation of the twist direction of an electroconductive polymer spiral on the DNA matrix; i.e., the optical activity of the polymer samples acquired is apparently associated with the biocatalyzer properties.  相似文献   
49.
A major determinant of plant architecture is the arrangement of branches around the stem, known as phyllotaxis. However, the specific form of branching conditions is not known. Here we discuss this question and suggest a branching model which seems to be in agreement with biological observations. Recently, a number of models connected with the genetic network or molecular biology regulation of the processes of pattern formation appeared. Most of these models consider the plant hormone, auxin, transport and distribution in the apical meristem as the main factors for pattern formation and phyllotaxis. However, all these models do not take into consideration the whole plant morphogenesis, concentrating on the events in the shoot or root apex. On the other hand, other approaches for modeling phyllotaxis, where the whole plant is considered, usually are mostly phenomenological, and due to it, do not describe the details of plant growth and branching mechanism. In this work, we develop a mathematical model and study pattern formation of the whole, though simplified, plant organism where the main physiological factors of plant growth and development are taken into consideration. We model a growing plant as a system of intervals, which we will consider as branches. We assume that the number and location of the branches are not given a priori, but appear and grow according to certain rules, elucidated by the application of mathematical modeling. Four variables are included in our model: concentrations of the plant hormones auxin and cytokinin, proliferation and growth factor, and nutrients—we observe a wide variety of plant forms and study more specifically the involvement of each variable in the branching process. Analysis of the numerical simulations shows that the process of pattern formation in plants depends on the interaction of all these variables. While concentrations of auxin and cytokinin determine the appearance of a new bud, its growth is determined by the concentrations of nutrients and proliferation factors. Possible mechanisms of apical domination in the frame of our model are discussed.  相似文献   
50.
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