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The investigation was intended to study the role ofbaroreceptors ofhemodynamically isolated zone of vertebral arteries in regulation of peripheral veins tonus, arterial pressure and external respiration. Pressure decrease in this vascular reflexogenic zone led to reflex responses of increase in femoral vein tonus, elevation of blood pressure level and stimulation of external respiration. The opposite reflex responses of cardio-respiratory functional system to initial pressure activation of vertebral arteries baroreceptors are observed. Basing on generalization of our own findings and similar physiological and morphological researches of other authors, it is established that afferentation from the vertebral artery zone is a reflexogenic factor of somatic muscles' veins tonus regulation. These reflexes of capacity vessels tonic activity changes are part of cardio-respiratory responses of maintaining the tissue gaseous exchange.

In spite of the complications after expander use the advantages of local plastics predetermine constant return to the method. Systemic use of hypoxic training produces stimulating effect on the skin microcirculation and can be used widely in clinical surgical practice in cases of local plastic operations to prevent possible complications reducing consequences of blood supply disturbance and tissue oxygen provision. The method of hypoxic adaptation let us receive as non-medicamentous mean to prepare for shorter period of time more vital flap.

Cardiointervalometry was used to investigate functional parameters of the cardiorespiratory system during text reading. A total of healthy women aged from 17 to 28 years and 11 women with hypotonic dysphonia 17 to 31 years of age entered the study. Both groups exhibited a low index of parasympathetic component of cardiorhythm regulation in shortening of the RR-interval. Correlation inhalation/expiration has changed with prolongation of inhalation and shortening of expiration in reading in women suffering from hypotonic dysphonia. Parameters of the respiratory cycle at rest did not correlate with relevant parameters in reading text in both groups.

Striking progress in the field of molecular chronobiology has been made during the last years. It renders us to reconsider some traditional viewpoints concerning circadian system functioning. Not only we are able now to explain basic concept of how clock genes pass through transcriptional and post-transcriptional pathways and how circadian system eventually "comes to life" at the cellular level, but we are also in position to speculate on how the whole organism constitutes its space-temporal order and how certain ultradians and infradians could be generated. Herein we propose a concept of multifuctorial genesis of chronomes and suggest terms such as "input rhythm" (or influencing rhythm) and "output rhythm" (or modulated rhythm). We stress on a viewpoint that the majority of investigated variables are multifuctorial by its nature because of vast net of regulatory mechanisms lied down in between the molecular basis of the clock and the output rhythms which are actually measurable by investigators. An attempt to follow down mechanisms of loss in the circadian temporal order (desynchronization) from the molecular level to that of a whole organism has been provided.

The new classifications of hypoxical, hypo- and hypercapnical conditions are elaborated. They take into account the ecological factors in the development of various kinds of exogenic hypoxia, hypercapnia. For the first time the positive sides of physiological hypoxia and hypercapnia are brought in. In all classification til the last days hypoxia was considered as pathological process only. However hypoxia can be met in different physiologic conditions of organism: internal period of fetus development, hard physical work, increased sportsmen activity, hypoxia after hearty meal, hypoxia of aged organism. The same it is possible to say about the hypo- and hypercapnical conditions.

After surgical denervation of sinocarotid reflexogenic zones and bilateral glomectomy in white laboratory rats oxygen consumption, rectal temperature, rate of cardial contractions and thermoregulatory activity of skeletal muscles display authentic increase. Glomectomy results in decreasing calorigecic effect of noradrenaline. Compensatory increase of thermoregulatory activity of sceletal muscles in response to beta-adrenogenic blocade with inderal in post-glomectomic animals is authentically less, than before inactivation of carotid receptors. In animals after carotid glomectomy resistance to acute hypoxia is clearly reduced. True reduction of number of erythrocytes, of hemoglobin concentration, of hematocrite parameter in post glomectic animals was found, which indicates anemisation phenomena. It was found that glomectomy after adaptation of animals in the mountains of Tien Shan at the height of 3200 m during 30 days didn't substantively change resistance to acute hypoxia. Resistance to acute hypoxia of animals living on mountains (susliks, marmots) is higher than of animals living on plains. Glomectomy performed on animals living on mountain resulted in an insignificant decrease in resistance to acute hypoxia. Resistance to acute hypoxia in postglomectic animals was found to be directly linked with absolute amount of hemoglobin concentration and erythrocyte number. In that way denervation of sinocarotid reflexogenic zones and bilateral glomectomy is an adequate method of comparative research of functions regulation mechanism during formation of adaptive responses in animals in dependence of various factors of external environment in norm, as well, as in pathology.

Geomagnetic effects on quantitative characteristics of alpha-rhythm were assessed by shifts in electroencephalograms recorded in 126 essentially healthy human subjects and changes in lipid metabolism in the cortex and white matter in 140 white rats. Indices of the geomagnetic activity were D, H and Z-components. The method of "epoch superposition" revealed an inconsistent alpha-rhythm depression and flattening out of the interhemispheric functional asymmetry against persistently high electrical activity in the right hemisphere, and biochemical asymmetry in consequence of different lipid transformation processes. Spotlighted were some nonspecific adaptive reactions to changes in the environment and stressful agents.

Changes in a number of respiration and circulation parameters during magnetic storms of varying intensity were analyzed in 126 normal humans belonging to two age groups: 19-21 yr. old young men and women (29 of each) and 51-53 yr. old men (n = 36) and women (n = 32). Geomagnetic components D, H and Z were used. Systolic pressure, respiration volume, minute respiration volume and peak expiration rate were shown to be the most labile characteristics of the cardiorespiratory system responding by increases on magnetodisturbed days. The parameters under study exhibited sexual and age differences equally on quiescent and magnetodisturbed days. Adaptation to growing tension of the magnetic field of Earth involves the neuroendocrine system and manifests itself by activation of the sympathetic nervous system entailing relative shifts in the cardiorespiratory parameters under study.

The aim of the present study is to investigate dynamics of the hemostasis system and structural and functional state of thrombocyte membranes by the LPO and AOD parameters under the conditions of expedition and shift organization of labour of worker tripping from the West Siberia middle latitudes to the Far North. A trend to hypocoagulemia and increases in LPO and AOD reactions were characteristic of the type-1 (adaptive) reaction. The type-2 (hypotensive) reaction included a trend to hypercoagulemia, an increase in LPO and a decrease in AOD reactions in thrombocyte membranes as well as a hypertensive reaction during the whole shift period. The type-3 (asthenic) reaction was described by hypocoagulemia, an increase in the amount of LPO products with a simultaneous decrease in the AOD activity and asthenic sleep disturbance.

The authors studied physiologic peculiarities associated with cardiorespiratory response to hypoxia and hypercapnia in various climate and geographic conditions, to combined effects of hypoxia, hypercapnia and physical burden, in artificial atmosphere with various velocity of hypoxia and hypercapnia increase. The studies were based on a hypothesis of universal mechanism that describes regulation of gas-transporting system and is aimed to supply oxygen to the body under ecologic hazards. The authors revealed similarity of circulatory and respiratory responses to hypoxia and hypercapnia in various ecologic circumstances.

The authors present results of theoretic and experimental analysis of ecologic safety in Russia. New composite discipline--"human ecology"--takes an important place in solution of medical and ecologic problems associated with correlation between natural and occupational factors influencing humans. Present medical, social and ecologic circumstances define the most vital scientific and applied directions covering medical and ecologic humanization of occupational and natural environment for humanity nowadays. Those directions are prophylaxis of ecologic stress, specification of informational technology for medical and occupational monitoring, creation of data bank on human ecology.

The article reviews the factors of abiotic and biotic environments liable to provoke convulsions. An assumption is made that the common element of their action on the organism are hypoxic states of varying types and depth. Animals with high individual tolerance of acute hypoxia were found to possess a better resistance to the convulsing effect of penicillin. In these animals the epilepsy-form discharges appear with longer latent periods and the epilepsy-form seizures are generated much more seldom in contrast to rats with poor tolerance of hypoxia. Training of resistless rats in the altitude chamber increases their ability to oppose the convulsing effect of penicillin to the level of animals with moderate but not high hypoxia tolerance.

The authors give their judgment of the cardiorespiratory status of the population in the ecologically disaster area to the south of the Aral. The data from examination of various age groups of the native population inhabiting eco-varying regions are published. The authors make a conclusion about an important role of environment in formation of the bronchopulmonary system.

The paper reports the data of comparative study of the cardiorespiratory function in healthy males (19-22 year old) from the countries in Asia, Africa, and Latin America lying within the tropic climatic-geographical zone during acute adaptation to the nature and the climate of the middle zone of Russia. The distinctions in respiration, circulation and gas exchange functions in the natives of different climatic-geographical zones were found as during comparative rest so under the combined effects of hypoxia and hypercapnia induced by the rebreathing test and ascribed to the environmental-genetic constitutional properties of the body and the chronobiological characteristics of the place of abode. Reactivity to the combined effects of hypoxia and hypercapnia in different groups is predominantly a function of unequal contributions of hemodynamics and pulmonary ventilation. A relatively low effectiveness of the cardiorespiratory system in representatives of the South-East Asia during acute adaptation was established. These results demonstrate the benefits of the hypoxic-hypercapnic test for determining functional potentials of the cardiorespiratory system in the context of adaptation to a new environment.

An overview contains the analysis of controversial literary data on possible therapeutic and pathogenic effects of electromagnetic fields on humans. The non-specific character of body shifts induced by electromagnetic fields with a prevalence of adaptive reactions at the onset and an emergence of dysadaptive processes during extremely long exposure was displayed. The leading role in the development of a therapeutic or pathogenic effect is played by the functional characteristics of an individual postulating the interaction of cumulative and adaptive processes in the body during long-term exposure in an electromagnetic field.

The purpose of this study was analysis of forensic medical aspects of macro- and trace element composition of hairs of the head in the residents of Mexico, Ecuador, Bolivia, Brazil, Columbia and changes in this characteristic during adaptation to conditions of Central Russia. One of our tasks was to define expert criteria for differentiation between the hairs belonging to residents of these countries and Russia. A total of 136 hairs were examined by spectral approximated quantitative analysis using DFS-13 spectrographer. The detected regularity consisted in the following: adaptation of residents of Latin America to conditions of Central Russia was associated with disappearance of some elements and appearance of other ones characteristic of residents of Central Russia (Byelorussians, Russians, Ukrainians).

Hypoxic and convulsive resistances have daily rhythms, the pattern of which depends on the year season. Latent period of occurrence of epileptic seizures and time of life at the "height" of 11,000 m above the sea level undergo similar changes in autumn and spring. In winter minimal similarity between daily dynamics of each of these resistances and analogous ones in other seasons is observed, but rhythms of tolerance to hypoxia are maximally synchronized with the rhythms of convulsive resistance. In autumn hypoxic and convulsive resistances are minimal. Maximums of these indices are observed in different seasons: for tolerance to hypoxia it is summer, for convulsive resistance--spring.

The direct effect of infralow-frequency (0.05, 0.1, 0.25 Hz, 100 nT) magnetic fields (MF) was demonstrated on the brain cellular--tissue model--surviving slices of mouse cerebellum. MF influence is a trigger for the nervous cells. MF-5 Hz revealed two-phases response: inhibition and excitation of the impulse activity of neurons. Besides that we recorded convulsive effect of MF. The experiments with simultaneous exposure of hypoxia and MF revealed a prohypoxia effect of MF, when the oxygen concentration was very low and also after reoxygenation. The surviving slices may be used as a model for studying the fine mechanisms of influence of different intensity MF on the nervous cells.

Research was conducted studying the peculiarities of development of pharmacological kindling in rats with different tolerance to hypoxia. Kindling was evoked by injecting subconvulsive doses of corazol (25 mg per kg) every day. Intensity of convulsions was expressed in points. Reliable distinction in intensity of convulsion between low-tolerant rats and high-tolerant rats to hypoxia was found on the 17th day of stimulation; amongst the group of low-tolerant rats the intensity of convulsions was found to be 2.46 + 0.30 points, and amongst the group of high-tolerant rats--1.20 + 0.22 points (p 0.05). On the 23rd day of injection the preparation convulsions in the group of low-tolerant rats reached up to 4.00 + 0.20 points and in the group of high-tolerant rats 2.28 + 0.45 points (p 0.01). The changes of violation of behavior were found to be different. Thus, the higher the individual resistance to hypoxia, the more is the resistance of the animal to the effect of epileptogens.

Hypoxic and convulsive resistances were studied in 3, 7, 14, 21, 40-day-old rats and in adults. Susceptibility to hypoxia was determined in pressure chamber by "lifting" the animals to the altitude of 12,000 metres. Convulsions were caused by intraabdominal injections of corazol. A correlation between hypoxic and convulsive resistances was found from 3 day after the birth. Their indexes were maximum at this period. Similar decrease of hypoxic and convulsive resistances was observed with the growth of the animals. Moreover the reduction in hypoxic resistance was more dramatic and reached its minimum on the 40th day. In grown up animals, resistance to hypoxia was higher, than in 40-day-old rats. Minimum latency period for development of status epilepticus was detected in 21-day-old rats.

Experiments on white random-bred rats showed that development of corazol seizures depend both on corazol dose and pO2 level in atmosphere. Latent period becomes short, the time of convulsive attack and the time of all seizures prolongs with increase of corazol dose. Acute hypoxia inhibits development of seizures: decreases the time of attack and the time of all seizures, prolongs latent period. The higher the hypoxia level is more massive its protective effect on corazol seizures. The anticonvulsant mechanisms of acute hypoxia are under discussion.