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The first results of U–Pb (LA–ICP–MS) isotope dating of detrital zircons (dZr) from the Upper Oligocene sands of the Poltava Formation exposed on the southeastern slope of the Voronezh anteclise are presented, providing information on the provenance sources. It is established that the dataset of dZr ages (provenance signal) is characterized by a predominance of ages within the range of 1–2 Ga with a low number of Phanerozoic, Late Proterozoic (younger than 1 Ga), and Archean dates. It is revealed that the cumulative ages of the complexes of the Svecofennian and Sveconorwegian orogens and, to a lesser degree, the Cadomides of Central Europe provide entirely the provenance signal recorded in the sands of the Poltava Formation. The data obtained allow us to refine the paleogeography of the Paratethys northern margin during the Late Oligocene. It has been found that the Poltava Formation was accumulated due to water transport of sediments from intensively eroded structures of western Fennoscandia from the North Sea to the Scythian Sea.

The article considers the methods for surface strengthening of screw downhole motors rotors. The automated line and technology for rotors surface coating application are described.

A dynamic content of ceruloplasmin and medium-molecular peptides were studied in the blood serum of 28 patients with an acute clinical course of myeloblast-type leucosis during a scheduled chemotherapy. The mentioned biochemical criteria were shown to be able to characterize indirectly an intensity of the clinical course, functional liver condition and the efficiency of chemotherapy.

Content of polyamines and extracellular DNA were studied in blood of patients with acute leukoses which did not respond to chemotherapy. Concentration of total polyamines was distinctly lower in blood of patients with acute lymphoblast and myeloblast leukoses as compared with healthy persons. Free and total polyamines were unaltered in blood of these patients after cytostatic therapy. In the patients with acute leukoses content of extracellular DNA was 2-fold higher as compared with controls. The high DNA content was maintained during the therapeutic course. Absence of any alterations in the biochemical patterns studied suggest that the patients with acute leukoses did not respond to the course of treatment used.

A simple and highly sensitive method was suggested for fluorometric determination of DNA content in human blood leukocytes. The method is based on the ability of fluorochrome bisbenzimide to bind specifically to DNA of cell homogenates in the presence of 2.5 M NaCl. This method makes it possible to do without preliminary treatment of cell homogenates aimed at the destruction of RNA and proteins, having a strong effect on the fluorescence of DNA complexes with other specific dyes. The technique was used to determine DNA amount in human blood leukocytes of 15 healthy people 23 to 47 years old (8 women and 7 men). DNA content averaged 7.4 +/- 0.35 pg/cell. The minimum detectable DNA concentration was 0.02 micrograms/ml.

It has been first demonstrated that DNA concentration in the plasma of healthy donors was 5 to 30 mu kg per I ml of plasma or 10-50% of DNA content in leukocytes contained in the same blood volume. DNA plasma concentration was determined by registering DNA-bisbenzimide complex fluorescence in supernatant derived from plasma containing 10% NaCl upon heating for 2-3 min at 100 degrees C. The method is simple, specific and permits the determination of DNA concentrations in 0.05-0.1 ml of plasma samples.

A procedure is described for fractionation of DNA obtained from leukocyte lysates of healthy donors and of patients with chronic leukoses using silica gel column chromatography. Lymphocytes and granulocytes of healthy donors as well as leukocytes from patients with chronic lympho- and myeloleukosis were dissimilar in the fractional composition of DNA. Nucleotide composition was studied; content of the DNA I fraction varied distinctly both in healthy donor granulocytes and in leukocytes of patients with chronic myeloleukosis as well as in leukocytes of patients with chronic lympho- and myeloleukosis. All the DNA fractions from leukocytes of healthy donors and of patients with chronic leukoses were dissimilar also in content of 5-methylcytosine.