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81.
Pinch-induced catalepsy and thyptophan hydroxylase (TPH) activity in striatum and midbrain were determined in male mice of 6 inbred strains. Pronounced catalepsy was found in the only mice strain--CBA. TPH activity in midbrain and especially in striatum of CBA mice was higher than in the strains, which did not display catalepsy. The experimental situation, which promotes the development of highly aggressive CBA males, caused a decrease in TPH activity in striatum and these mice did not express genetic predisposition to catalepsy. The results indicate that TPH activity in striatum is involved in the mechanism of catalepsy in mice.  相似文献   
82.
The results have been presented of the zymosan (Z) effect mechanism in the reaction of the lipid peroxidation and the parts' separation of the protection antioxidant. The experiments were made on 32 Wistar rats. At the experimental series 25 mg/kg and 100 mg/kg of Z were injected. Control rats were injected with physiological saline alone.  相似文献   
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The allele and genotype frequencies of 14 SNPs of renin-angiotensin (REN, AGT, AGTR1, AGTR2, BKR2, and ADRB2) and hemostasis (FGB, F2, F5, F7, ITGB3, SERPINE1, MTHFR) system genes, as well as of the ACE insertion-deletion polymorphism, were analyzed in patients with ischemic stroke and in healthy controls matched by age, sex, and ethnicity. Genotyping was performed through the amplification of the selected gene sequences and subsequent hybridization of the labeled fragments with SNP-specific DNA probes on the biochip. There were no significant differences in the allele frequencies of individual genes between the groups of stroke patients and healthy donors. The contribution of the renin-angiotensin and hemostasis system genes to the genetic susceptibility to ischemic stroke in Russians from central Russia was also assessed using the MDR (Multifactor Dimensionality Reduction) approach. The genotype combination FGB G/- x ACE I/- x MTHFR C/- x SERPINE1 5G/5G, the frequency of which was significantly higher in patients with stroke than in healthy controls, was associated with an increased risk of ischemic stroke (P = 0.03, OR = 2.4, 95%CI 1.1?C5.3).  相似文献   
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86.
Analysis of the content of CD16/32+, CD4+ and CD8+ -cells was perfomed in the peripheral blood and spleen ofmice of the ASC strain with high predisposition to depressive-like state in comparison with mice of parent CBA strain having no depressive behaviour. In both cases, ASC mice showed a decrease in the percentage of CD16/32+ and CD4+-cells along with an increase CD8 cells and lowering of immunoreactivity index (CD4+/CD8+). Changes in cellular subpopulations found in intact ASC mice was accompanied with animals' low capacity to respond to T-dependent antigen: sheep red blood cells at the dose of 5 x 10(8). In contrast to CBA mice the percentage and absolute number of IgM-antibody-forming cells were significantly decreased in the spleen of ASC mice on the 4th and 5th days after immunization as well as the numbers of IgG-antibody-forming cells on the 6th day of the immune response. Possible mechanisms underlying the immune reactivity inhibition under depressive-like state are discussed.  相似文献   
87.
88.
Biopharmaceutical industry currently produces considerable quantity of novel recombinant preparations by way of overexpression in Escherichia coli cells, an inexpensive, efficient, time-proven, and practically feasible system of heterologous expression. Due to the instability of maintenance and inheritance of expression vectors in producer cells, the cells that have spontaneously lost the plasmid gain a significant selective advantage over the cells producing a heterologous protein and accumulate in the fermentor. For solution of this problem, it is proposed to develop a new generation of expression vectors with high stability of inheritance in the absence of external selective pressure, using a replicon of phage N15, which possesses its own system for active distribution of plasmid copies in the daughter cells, supplemented by a toxin-antitoxin genetic module preventing the loss of a plasmid. Two new addiction modules homologous to the known ccdAB and mazEF systems were isolated from natural enterobacterial populations and characterized. The testing showed more effective operation of the ccdAB module. The latter was a basis for construction of new expression vectors pN15E41 and pN15E61 demonstrating the high synergism of action of the plasmid segregation systems and the addiction module and directly applicable for biotechnological practice.  相似文献   
89.
The aim of this study is to test the hypothesis about an inconsistency in time estimation of the divergence and topology of species Drosophila kanekoi, D. ezoana, and D. littoralis which is caused by the irregular accumulation rate of replacements in different DNA sequences used for analysis and in evolutionary lineages. The phylogenetic relationships based on sequences of five genes among 11 Drosophila species of the virilis group are revised, and estimation of molecular clock regularity in several phylogenetic lineages of this group is given. It was shown that Drosophila kanekoi, D. ezoana, and D. littoralis contituted in a single cluster, which was most related to the subphylad montana. The irregularity of molecular clocks was shown for the highly conservative sequences of the mt 12S-16S rRNA and Ras1 genes, the replacements of which were predominantly neutral. The irregularity of the molecular clock between several phylads and phylogenetic trees of subphylads lummei and kanekoi was revealed.  相似文献   
90.
We studied the fertility of D. melanogaster females heterozygous for the dominant temperature sensitive mutation l(2)M167 DTS , which exerts a recessive lethal effect at 25°C, under the conditions of stable temperature regimes 25, 28, and 29°C and changing regimes 25 → 29°C and 29 → 25°C. It was shown that inhibition of total activity of oogenesis due to a decreased number of functioning ovarioles is one of the mechanisms underlying the decreased fertility of l(2)M167 DTS /+ females. Analysis of individual fertility of each female confirmed also the role of sterility as a component of fertility of the females. Sterilization was realized due both to full depletion of functioning ovarioles and disturbed mechanism of laying the mature eggs onto a substrate as a result of violation of the feedback blocking normal ovulation, which led to the breakdown of ovarioles and filling of the abdominal cavity with mature oocytes. A significant polymorphism of heterozygous females by their fertility was observed. The intensity of sterilization and mortality of l(2)M167 DTS /+ females sharply increased at an elevated temperature (29°C), especially at the pupal stage.  相似文献   
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