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1.
NeIX and NeX spectra emitted by the PF-3 high-current (2 MA) plasma focus facility are measured. A numerical model describing the spectral intensities of the emission of helium- and hydrogen-like neon ions from an optically thick plasma is proposed. The electron temperature T e and electron density n e in the plasma of the PF-3 facility are determined by comparing the calculated and measured emission spectra of neon.  相似文献   
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The dynamics of the cumulative jet formed in the course of plasma compression in a plasma focus discharge is investigated by the method of differential optical interferometry. The jet propagation velocity is found to be V = (2.3?C3) × 107 cm/s, which coincides with the results of calculations performed in a 2D ideal MHD model. Ejection of matter from the anode in the late stage of the discharge due to the interaction of the cumulative jet and the electron beam with the anode surface is observed.  相似文献   
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It is known that the frequency of chromosomal abnormalities among spontaneous miscarriages of the first trimester of pregnancy makes 50-60%. Research of karyotypes of chorionic villus cells of miscarriages has been conducted by combining the standard cytogenetic method and the FISH analysis on interphase nuclei of centromeric specific DNA samples by the tests to the chromosomes 13/21, 14/22, 15, 16, 18, X, Y. The described complex approach can be successfully applied for effective identification ofchromosomal abnormalities in the material of spontaneous miscarriages. The results specify the necessity of careful study of genomes of matrimonial pairs with the usual unmaturing in anamnesis and especially before treatment by IVF methods.  相似文献   
4.
Results of cytogenetic and molecular-cytogenetic inspection of 210 matrimonial pairs with the problems of reproduction are presented. Different types of chromosomal aberrations have been detected in the karyotypes of the patients in 46 (10.95%) cases. Such structural chromosomal aberrations as pericentric inversions, Robertsonian translocations, balanced reciprocal translocations, and marker chromosomes as well prevailed the numerical chromosomal aberrations (89.13% and 10.87% cases accordingly). In the general group of the inspected patients there were 19 cases (4.52%) characterized by the low level of X and Y chromosome mosaicism. The authors suppose that the patients with the exposed chromosomal abnormalities need the differentiated approach at their treatment.  相似文献   
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We present the prenatally identified case of mosaicism of chromosome 16 trisomy. A patient with the pregnancy complicated in the first trimester by the threat of breaking was refered to the high risk group according to the results of the screening program. The ultrasonic research revealed a number of phenotypical pathologies in 19-weeks-old fetus such as congenital heart disease (ventricular septal defect), hyperechoic bowel, single umbilical artery and some other ones. Cytogenetical and FISH analyses of the placental villi revealed karyotype with chromosome 16 trisomy. The further research of amniotic fluid cells revealed the karyotype of fetus as mos47,XX,+16 / 46,XX. The pathologoanatomic research of the abortus has verified the multiple congenital malformations.  相似文献   
7.
A population of Stratiomys japonica, a species belonging to the family Stratiomyidae (Diptera), common name ‘soldier flies’, occurs in a hot volcanic spring, which is apparently among the most inhospitable environments for animals because of chemical and thermal conditions. Larvae of this species, which naturally often experience temperatures more than 40 °C, have constitutively high concentrations of the normally inducible heat-shock protein Hsp70, but very low level of corresponding mRNA. Larvae of three other species of the same family, Stratiomys singularior, Nemotelus bipunctatus and Oxycera pardalina, are confined to different type semi-aquatic habitats with contrasting thermal regime. However, all of them shared the same pattern of Hsp70 expression. Interestingly, heat-shock treatment of S. japonica larvae activates heat-shock factor and significantly induces Hsp70 synthesis, whereas larvae of O. pardalina, a species from constant cold environment, produce significantly less Hsp70 in response to heat shock. Adults of the four species also exhibit lower, but detectable levels of Hsp70 without heat shock. Larvae of all species studied have very high tolerance to temperature stress in comparison with other Diptera species investigated, probably representing an inherent adaptive feature of all Stratiomyidae enabling successful colonization of highly variable and extreme habitats.  相似文献   
8.
The results of a molecular cytogenetic study of the material of spontaneous abortions and nonprogressive pregnancies in the first trimester in 43 couples who were treated with various ART methods are presented in this paper. Chromosomal pathologies (CPs) were present in 28 (65%) samples of chorionic villi. A comparative analysis of the frequency and types of CPs in groups composed according to the pathological states in the semen of males was performed. Recommendations to improve the efficiency of ART are developed based on the data.  相似文献   
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The analysis of the cytogenetic anomalies frequencies in children with inborn defects of development was carried out, and the comparative evaluation of involving in cytogenetic anomalies of the individual chromosomes was determined. Chromosomes 9, 13 and 18 were most frequently involved in chromosomal anomalies. There no direct relations were revealed between peculiarities of inborn defects of development and definite cytogenetic anomalies.  相似文献   
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