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Biomedical subjects

V T Volkov

Publications and source records attributed to V T Volkov.

11 recordsLinked to original sources
PubMed2001

Superconductivity in ropes of single-walled carbon nanotubes.

We report measurements on ropes of single-walled carbon nanotubes (SWNT) in low-resistance contact to nonsuperconducting (normal) metallic pads, at low voltage and at temperatures down to 70 mK. In one sample, we find a 2 orders of magnitude resistance drop below 0.55 K, which is destroyed by a magnetic field of the order of 1 T, or by a dc current greater than 2.5 microA. These features strongly suggest the existence of superconductivity in ropes of SWNT.

Journal Article↗
PubMed2001

Proximity-induced superconductivity in DNA.

Conductivity measurements on double-stranded DNA molecules deposited by a combing process across a submicron slit between rhenium/carbon metallic contacts reveal conduction to be ohmic between room temperature and 1 kelvin. The resistance per molecule is less than 100 kilohm and varies weakly with temperature. Below the superconducting transition temperature (1 kelvin) of the contacts, proximity-induced superconductivity is observed. These results imply that DNA molecules can be conducting down to millikelvin temperature and that phase coherence is maintained over several hundred nanometers.

DNA↗
PubMed1993

[Bronchial asthma in a hyperendemic focus of opisthorchiasis (western Siberia)].

The data obtained on bronchial asthma (BA) occurrence in the hyperendemic opisthorchiasis focus in the western Siberia show BA in it to run a more severe and prognostically unfavourable course against the population from other Siberian regions safer by opisthorchiasis. The latter adapted to hepatobiliary system negatively affects the bronchi and lungs due to the involvement of eosinophilic and immunocomplex mechanisms damaging BA patients' shock organ. By means of additional antigenic stimulus, opisthorchiasis sensitization changes BA clinical manifestations and immunological manifestations status of BA patients dictating the necessity of immunological correction. High BA incidence was registered among subjects who had come from areas where opisthorchiasis was encountered less frequently.

Adult↗
PubMed1988

[Analysis of trace elements and crystalline formations in the sputum in bronchial asthma].

The content of sputum trace elements was investigated in 12 patients with bronchial asthma (BA). The presence of Na, K, Ca, P, Mg, Si, Sn, Fe, Mn, Cu, Ti, Ag, Al, V, B was revealed. The absence of Zn and high levels of Ca and Sn were observed. Multiple crystalline Ca precipitates (phosphates, carbonates and oxalates) were found in the sputum of 56 BA patients. Ammonium urate and uric acid were also revealed. The author supposed disturbance of calcium homeostasis and purine metabolism in BA patients, involvement of the detected crystalline formations in the pathogenesis of BA obstruction bronchospasm and deterioration of sputum rheological properties.

Adult↗
PubMed1985

[Bronchial asthma and arterial hypertension].

Study of the clinical data concerning patients suffering from bronchial asthma and analysis of the autopsy data allow the conclusion about the presence of a pathogenetically validated symptomatic arterial hypertension including its drug patterns. The increased number of cases of bronchial asthma and arterial hypertension constellation attests to a considerable unbalance of the autonomous nervous system, alterations of the sympathoadrenal effects in such patients, which makes the clinical picture and course of modern bronchial asthma more complicated. The pathogenetic approach to the treatment of such patients characterized by hypersensitivity to the environmental factors, stress situations and to drugs which stimulate the sympathoadrenal system will permit one to avoid diagnostic, deontological errors, to choose sound therapy including measures aimed at preventing arterial hypertension itself.

Asthma↗