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81.
An experimental study on the zooplankton community in the thickets of elodea Elodea canadensis Michx. of different densities (2, 4, and 8 g/L, wet weight/L) has been conducted. It is revealed that specific cationic composition and pH and sharp daily fluctuation of oxygen concentrations is a characteristic of the water in dense thickets of plants. Changes in water chemistry and in spatial organization of the environment influence zooplankton diversity and population dynamics of some species. With an increase in density of thickets, the number of Daphnia longispina O.F. Müller decreases, while the share of predators (Cyclopidae and Polyphemus pediculus O.F. Müller) increases. The abundance of Ceriodaphnia quadrangula (O.F. Müller) increases in the presence of plants, but does not depend on the density of the thickets. The correlation between the development of Simocephalus vetulus (O.F. Müller) and Diaphanosoma brachyurum (Liévin) and water cationic composition, changing in the process of growth and senescence of plants, is revealed.  相似文献   
82.
The data are presented on the cloning and structural analysis of the cDNA coding for human prointerleukin-1 alpha and prointerleukin-1 beta (proIL-1 alpha and proIL-1 beta). The nucleotide sequences of proIL-1 alpha and proIL-1 beta cDNAs have been compared with the sequences published earlier. The nucleotide changes resulting in the aminoacid changes of the protein were not found. Some nucleotide changes were identified within the 3'-nontranslated region of the proIL-1 beta cDNA. The existence of the allelic variants for interleukin genes registered only on the gene level has been supposed.  相似文献   
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Medical records and questionnaire data have been used to analyze morphophysiological (the birth weight and length) and genetic demographic (maternal age and marriage structure) traits in a sample of children with orofacial malformations (OMs, cleft palate and/or cleft lip) living in Krasnodar Territory, Russia. The sample of children with malformations (including premature infants) differs from the control group in lower birth weight and length and a lower proportion of children with morphophysiological values close to the population average ones, as well as a higher family exogamy level estimated on the basis of marriage structure in the parental and preceding generations. The risk of congenital cleft palate and/or cleft lip is considerably increased is the maternal age is older than 35 years or, to a lower degree, if it is younger than 20 years.  相似文献   
85.
The capacity of dried Klebsiella cell-free vaccine, obtained from strain No. 204 by the disintegration of microbial mass with hydroxylamine, for protecting mice from pneumococcal infection caused by S. pneumoniae, serotypes 3, 4 and 9N, has been studied. Klebsiella vaccine has been found to possess immunostimulating potency with respect to the S. pneumoniae serotypes under study. On day 5 this potency is manifested to a greater extent than 24 hours after immunization. The combination of Klebsiella vaccine with Proteus vulgaris, Staphylococcus aureus and Escherichia coli K-100 antigens enhances the stimulation of nonspecific resistance.  相似文献   
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Codon 312 and 751 polymorphisms ofXPD gene and codon 399 polymorphism of XRCC1 gene of peripheral blood lymphocytes in patients with Down syndrome (DS) (46 individuals), Ehlers-Danlo syndrome (EDS) (47 individuals) and in a group of healthy donors (control) (40 individuals) have been studied. Frequency of XPD genotype (G312G) coding for the most effectively functioning form of XPD protein was lower in patients with DS (26%) than in a group of healthy donors (42.5%) (p = 0.035), whereas no significant differences with the control were revealed for this codon in patients with EDS. No patients with XPD genotype (C751C) (p = 0.036) were revealed in a group of EDS patients, while this genotype was found in 16% of a group of healthy donors and in 17% of patients with DS. The trend of XRCC1 genotype frequency reduction (A399A) (p = 0.085) in EDS patients (3.9%) compared with the group of healthy donors (13.5%) and DS patients (13.3%) has been obtained. These data show that polymorphisms of the excision repair genes under study are accompanied by an elevated individual radio sensitivity in patients with DS. Genes investigated (their polymorphic variants) did not participate in the mechanisms for radio sensitive phenotype formation in EDS patients.  相似文献   
89.
Intracellular organelles, peroxisomes, occur in cells of most eukaryotic species. Human severe congenital disorders are associated with defective assembly and functioning of peroxisomes, which partly explains the attention of researchers paid to peroxisome biogenesis. It has been shown that peroxisomes are involved in the realization of eukaryotic developmental programs (in particular, neuroblast differentiation and postembryonic development). Cytobiochemical and electron-microscopic studies of peroxisomal mutations showed that the primary role in peroxisome biogenesis is played by synthesis of specific proteins (peroxins) and their transport and incorporation into peroxisome membranes. More than 30 peroxin-encoding genes have been examined. These proteins are synthesized on free polysomes and transported into peroxisomes by means of specific signaling peptides, PTS1, PTS2, and PTS3. The import of matrix proteins depends on at least two shuttle receptor proteins, Pex5p and Pex7p. Some proteins regulating peroxisome proliferation in cells have been identified.Translated from Genetika, Vol. 41, No. 2, 2005, pp. 149–165.Original Russian Text Copyright © 2005 by Kurbatova, Dutova, Trotsenko.  相似文献   
90.
Protective efficacy of secreted proteins of Streptococcus pneumoniae and Klebsiella pneumoniae cultivated on cardiocerebral broth and semisynthetic growth medium respectively was studied in vivo. Fraction with molecular weight 30 - 50 kDa obtained by the method of membrane fractionation had high protective efficacy. Two-dose immunization of mice with this fraction provided 80 - 100% protection from infection by homologous strains of S. pneumoniae and K. pneumoniae. Cross-protective activity of the fraction was revealed when infecting immunized mice by different K-types of K. pneumoniae. Blood sera of mice immunized with 30 - 50 kDa fraction possessed preventive features protecting from infection 90% of animals while 100% of death in the control group. It was determined that protective efficacy of the mentioned fraction was determined by protein-containing antigens because proteolytic disruption of the protein component resulted in loss of protective properties of the preparation.  相似文献   
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