Olga A. Romanova

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A mutation outburst of the yellow gene occurred in a Drosophila melanogaster population from the town of Uman' from 1982 to 1991 and was associated with the instability of several alleles. Molecular genetic analysis revealed a deletion variant of the hobo transposable element in the same site of the regulatory region of yellow in the mutant alleles and(More)
In 1981 recurrent local bursts of mutability of the yellow gene were observed in a natural population of Drosophila melanogaster from Uman' (Ukraine). A series of y 2 -like mutations in the yellow gene were recovered during the period 1982 to 1991. Most of the mutants display the y2-phenotype, i.e. mutant yellow color of wings and body cuticle. Ninety-nine(More)
We compared the structure and mechanical properties of scaffolds based on pure collagen, pure chitosan, and a mixture of these polymers. The role of the composition and structure of scaffolds in the maintenance of cell functions (proliferation, differentiation, and migration) was demonstrated in two experimental models: homogeneous tissue analogues(More)
We apply the generalized Jordan sets techniques to reduce partial differential-operator equations with the Fredholm operator in the main expression to regular problems. In addition this techniques has been exploited to prove a theorem of existence and uniqueness of a singular initial problem, as well as to construct the left and right regularizators of(More)
Precursors of malignant melanoma are special pigment spots characterized by proliferation of atypical melanocytes accompanied by reactive lymphoplasmocytic infiltration of the derma designated as lentiginous melanocytic dysplasia (LMD), a variant of Dubreuilh melanosis. The material of the study of 53 cases of LMD and the time course of its progress suggest(More)
Earlier, we described the mechanism of formation of superunstable mutations that are associated with the insertion of chimeric elements containing unique fragments of the Drosophila genome flanked with copies of P-elements [1, 2]. Mobilization of P-elements results in inversions, deletions, duplications, and increase or decrease in the DNA fragments located(More)
Malignant melanomas are known to be prone to undergo spontaneous regression (spontaneous resorption). The morphological picture of this process similar to that in spontaneous regressions of nevuses (halo-nevus), pigmentous spots (Dubreille melanosis) and superficially spreading melanoma is described. Six observations of spontaneously regressing melanomas(More)
Under examination was the possibility to reveal clinico-immunological features in patients with soft tissue sarcomas prior to and after surgery. Different immune responses were observed in patients with various forms of tumor progression. In case of a favourable course of the process surgery somewhat stimulates the cell immune response and reduces the titre(More)