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To assess endothelial function in the newborns born to mothers with preeclampsia and without preeclampsia the scientists assessed the content of nitricoxide and hydrogen sulfide in the umbilical and venous blood of these children. The main group consisted of 80 women with moderate preeclampsia and their80 newborns; the control group included 50 children born to women without preeclampsia. The authors studied the content of nitric oxide by determining the totalnitrates and nitrites (NOx), hydrogen sulfide in mixed cord blood collected within 30 minutes after delivery, and venous blood taken from newborns on the 1-3rd day of life. Umbilical cord blood demonstrated no significant differences in the content of NO xand hydrogen sulfide in newborns of the main and control groups. However, in general, the study of umbilical cord blood revealed a relationship between the concentration of hydrogen sulfide and the possibility of developing intraventricular hemorrhagein a newborn of the main and control groups. In the venous blood there was a significant increase in the content of NOx and hydrogen sulfide in newborns born to mothers with preeclampsia. It may cause vasodilation asa compensatory reaction of the body during the period of postnatal adaptation of the child’s body, aimed at life support.

The article presents the results that reveal the features of the state of the hypothalamic-pituitary-gonadal axis and the level of dopamine in apparently healthy men with different adaptive potential of the circulatory system, taking into account age and territory of residence. Material and methods. The study involved 155 men (90 residents of the European North (Arkhangelsk Oblast) and 65 residents of the Asian North (Yamalo-Nenets Autonomous Okrug)) aged 22–59 years. Serum hormone levels of the hypothalamic-pituitary- gonadal axis were determined by enzyme immunoassay and radioimmunoassay in vitro analysis. The adaptive potential was calculated according to R.M. Baevsky. Results and its discussion. The functional tension of the mechanisms of adaptation of the circulatory system in men of the European North and unsatisfactory adaptation in men of the Asian North were revealed. In the studied regions of the North, there are no people with good and satisfactory adaptation, and the group of people with a breakdown in adaptation was identified only in the Asian North in men aged 45–59 years, which allows us to classify these subjects as a risk group for developing cardiovascular diseases. In men of the European North, the unsatisfactory adaptation was combined with an increase in the levels of prolactin (at the age of 22–44 years) and follitropin (at the age of 45–59 years) and a decrease in the level of sex hormone-binding globulin (at the age of 22–44 years). A decrease in the levels of total and free testosterone can be attributed to the key markers of failure of adaptation in men of the Asian North aged of 45–59 years. When analyzing the data of the entire surveyed population of men aged 22–59 years, an increase in aromatase activity was noted against the background of a decrease in testosterone levels in men of the European North with the 4th degree of adaptive potential and in men of the Asian North with the 5th degree of adaptive potential, which can be considered as a compensatory reaction to preserve the function of the cardiovascular system.

Extramedullary hematopoiesis is a normal compensatory reaction that can affect the epidural space, leading to spinal cord compression syndrome. MRI is the imaging method of choice for diagnosis and monitoring. Treatment is still controversial.

In order to study the medical and social characteristics of families, an analysis of the biological and social history of mothers and fathers of children born with a body weight less than 1500 was carried out. To identify the psychological characteristics, mothers were tested.It has been established that the social characteristics of the families of children born with a body weight of less than 1500 g was favorable – most families were two-parent, had satisfactory living conditions, mothers and fathers of these children were working and had education not lower than secondary special. The majority of fathers (80%) considered themselves healthy, the state of health of mothers was characterized by a high frequency of somatic pathology, only 27% of women were healthy. The majority of fathers and mothers noted the impact of occupational hazards, while the mothers’ adverse factors were mainly associated with intellectual activity, and the fathers – with physical labor. Half of mothers and 70% of fathers belonged to the age group of 30 years and older. Despite the favorable characteristics of reproductive behavior at the stage of pregravid preparation and in the first trimester of pregnancy, mothers who gave birth to children weighing less than 1500 g were characterized by an unfavorable obstetric gynecological history and a high incidence of gynecological pathology. Psychological features of mothers consisted in a high frequency of accentuation of hyperthymic character traits, a desire to emphasize determination and masculinity, anxiety, impulsivity, which may indicate a compensatory reaction to a stressful situation – the birth of a premature baby. This is also indicated by the high frequency of psychosomatic (45.9%) and authoritarian (29.5%) types of attitude to the problems of the child. In this regard, only 62.2% of mothers established optimal emotional contact with the child by the end of the neonatal period. The revealed psychological characteristics of mothers require early psychological and psychotherapeutic correction to successfully overcome the stress of giving birth to a premature baby and consolidate all the efforts of a woman for habilitation.

We examined 70 women who were 22-40 weeks pregnant and their newborns. Of these, 15 women with moderate PE made up group 1, 22 women with severe PE-group 2, and 55 women with uncomplicated pregnancy without hypertensive disorders - the control group. Blood was collected from women when they were admitted to the clinic, and blood was taken from newborns for 3-5 days of life. The concentration of hydrogen sulfide was determined by the method of K. Qu et al [17]. There was a decrease in the level of hydrogen sulfide in the blood serum of women whose pregnancy was complicated by severe preeclampsia. In newborns born to mothers with preeclampsia, an increase in the concentration of hydrogen sulfide was detected in the blood, which is probably a compensatory reaction aimed at restoring vascular homeostasis during early postnatal adaptation.

The article presents the results of determining the level of expression of genes encoding GABA receptor subunits GABRA1, GABRB2, and GABRG2 in the hippocampus of rats 24 hours after a single intramuscular administration of the antagonist of the chloro-ion channel of GABA receptor of kloflubicin in a dose of LD25, LD40, LD50, and LD75. It is revealed that kloflubicin has no influence on the relative level of GABRG2 gene expression. At the same time, the relative level of GABRA1 gene expression increases 7,5, 7,0, and 5,0 times after administration of kloflubicin in a dose of LD40, LD50, and LD75, respectively. The relative level of GABRB2 gene expression also increases 3,6 and 2,6 times after administration of kloflubicin in a dose of LD50 and LD75, respectively. It is assumed that increase in the level of gene expression of GABRA1 and GABRB2 in rats after administration of kloflubicin in doses above LD25 is a compensatory reaction of the body to the effect of physiologically active substance, and subunits encoded by these genes α1 and β2, respectively, are included in the mechanism of convulsive effect.

The work is devoted to the study of the effect of interval hypoxic training on the state of microcirculation of the skin in rats in the experiment. The study was conducted on white male Wistar rats weighing 70 g ±10%. In order to study the state of the dynamic characteristics of blood microcirculation, a change in blood perfusion of the tissue was considered. A non-invasive method for quantifying microvascular perfusion was used. The results showed that inhibition of microcirculation up to 50 % was observed in comparison to this value before exposure during the formation of a compensatory reaction of the body to a hypoxic effect on the 7–14th day of the experiment. It was noted that the predominant role in the regulation of the microvasculature belongs to the passive regulation factor of microcirculation which is characterized by the involvement of blood vessels in the microvasculature due to periodic changes in blood volume in the vessel together with an increase in the arithmetic mean perfusion rate. Thus, experimentally modulated hypobaric exposure, changes the volume of blood in arterioles that is determined by a pulse wave.

How organisms are able to maintain robust homeostasis has in recent years received increased attention by the use of combined control engineering and kinetic concepts, which led to the discovery of robust controller motifs. While these motifs employ kinetic conditions showing integral feedback and homeostasis for step-wise perturbations, the motifs’ performance differ significantly when exposing them to time dependent perturbations. One type of controller motifs which are able to handle exponentially and even hyperbolically growing perturbations are based on derepression. In these controllers the compensatory reaction, which neutralizes the perturbation, is derepressed, i.e. its reaction rate is increased by the decrease of an inhibitor acting on the compensatory flux. While controllers in this category can deal well with different time-dependent perturbations they have the disadvantage that they break down once the concentration of the regulatory inhibitor becomes too low and the compensatory flux has gained its maximum value. We wondered whether it would be possible to bypass this restriction, while still keeping the advantages of derepression kinetics. In this paper we show how the inclusion of multisite inhibition and the presence of positive feedback loops lead to an amplified controller which is still based on derepression kinetics but without showing the breakdown due to low inhibitor concentrations. By searching for the amplified feedback motif in natural systems, we found it as a part of the plant circadian clock where it is highly interlocked with other feedback loops.

Introduction. Traumaticity constitutes one of actual problems of urgent surgery. The lipids peroxidal oxidation (LPO) activation and the antioxidant defense (AOD) system depletion are important aspects of the hepatic dysfunction pathogenesis as well as hepatic insufficiency in the trauma environment. Маterials and methods. The closed abdominal organs (AO) trauma in combination with bilateral femoral fractures was simulated in experiment on 74 white rats. The hepatic content of the LPO products and activity of the AOD enzymatic unit were investigated. Results. Activation of the lipids peroxidation processes was observed in the laboratory animals liver in the AO combined trauma. Discussion. The results obtained witness the necessity for the LPO processes correction in complex of the AO combined trauma in early period of traumatic disease. Conclusion. Dynamics of the superoxiddysmutase and catalase activity, as well as of the antioxidant–prooxidant index, witness a significant compensatory reaction of the hepatic АОD system present in environment of the combined AO trauma.

In this study, we assessed the Atlantic surfclam (Spisula solidissima) energy budget under different ocean acidification conditions (OA). During 12 weeks, 126 individuals were maintained at three different ρCO2 concentrations. Every two weeks, individuals were sampled for physiological measurements and scope for growth (SFG). In the high ρCO2 treatment, clearance rate decreased and excretion rate increased relative to the low ρCO2 treatment, resulting in reduced SFG. Moreover, oxygen:nitrogen (O:N) excretion ratio dropped, suggesting that a switch in metabolic strategy occurred. The medium ρCO2 treatment had no significant effects upon SFG; however, metabolic loss increased, suggesting a rise in energy expenditure. In addition, a significant increase in food selection efficiency was observed in the medium treatment, which could be a compensatory reaction to the metabolic over-costs. Results showed that surfclams are particularly sensitive to OA; however, the different compensatory mechanisms observed indicate that they are capable of some temporary resilience.

Traditionally, lacerations of bridging vessels were surmised to cause chronic subdural hematoma (CSDH), although neither observation studies nor medical research was able to testify this. Nowadays, an inflammatory process is known to take place in the development of CSDH. Of note, post-traumatic angiogenesis at its early stage also features inflammation with immune cell infiltration. The authors found a patient suffering from CSDH with unusual angiogenesis between dura and pia matters. The observation of dura-and-pia angiogenesis may be a piece of evidence to underline compensatory reaction of central nervous system to offset the negative effects produced by CSDH, and points out to a possible approach of bolstering angiogenesis to manage ischemic diseases in cerebral hemispheres.

Results of a study of weight load imbalance in patients with lower limb prostheses and patients with upper limb post mastectomy edema are described. The composition of methods and measuring devices and the biomedical information necessary to assess imbalanced loads with structural and functional asymmetry in the locomotor apparatus considering compensatory reactions affecting it from the locomotor system is considered. The features of these reactions are revealed.

Using quantitative laser-scanning microtomography (QLSM), the response of mature mouse oocytes to hypotonic stress was investigated. The response exhibited the following features: (1) oocytes were capable of regulatory volume decrease (RVD); (2) unlike zygote and two-cell embryo, the oocyte volume recovery was not complete even by 120 min; (3) millimolar and submillimolar concentrations of glycine arrested the development of RVD in oocytes.

Expatriation research has been intrigued by the question of how to prevent the unplanned return of expatriates to their home country. Although a majority of studies have focused on assigned expatriates (AEs), only recently have researchers expanded the scope of analysis by focusing on self-initiated expatriates (SIEs). For SIEs, research has identified job embeddedness as a key explanatory concept for early repatriation without yet acknowledging its potential to also explain the early expatriation of AEs. However, because AEs and SIEs differ in important motivational and behavioral aspects, the lack of comparative studies prohibits a deeper understanding of the mechanisms through which job embeddedness influences early repatriation. We build on belongingness theory to conceptualize early repatriation as a compensatory reaction of expatriates to an inhibited need to belong. Using a unique sample of 345 expatriates from 40 countries, we show that off-the-job embeddedness is more important for explaining the repatriation intention of AEs than of SIEs, whereas on-the-job embeddedness is more important for explaining the repatriation of SIEs compared to AEs. Our integrative model carries important theoretical implications for expatriation research and provides managerial implications for recruiting and retaining AEs and SIEs.

Excessive poorly differentiated epitheliocytes were detected in the crypts and subepithelial regions of the colorectal mucosa during the regeneration process in the majority of patients with diverticular disease. The compensatory reaction of the sigmoid mucosa decreased, which was seen from rarely detected cryptic hyperplasia. Disorders in the epitheliocyte proliferation and differentiation were paralleled by changes in tissue levels of proinfl ammatory cytokines (elevation of TNF-α and IFN-γ and reduction of IL-1β and IL-8) and increase of IL-4, regulating lymphocyte activation.

In this study a driving simulator was used to determine changes in mental effort in response to manipulations of steering demand. Changes in mental effort were assessed by using subjective effort ratings, physiology, and the standard deviation of the lateral position. Steering demand was increased by exposure to narrow lane widths and high density oncoming traffic while speed was fixed in all conditions to prevent a compensatory reaction. Results indicated that both steering demand factors influence mental effort expenditure and using multiple measures contributes to effort assessment. Application of these outcomes for adaptive automation is envisaged. (C) 2010 Elsevier Ltd. All rights reserved.

Extramedullary hematopoiesis (EMH) occurs as a compensatory reaction to an underlying hematologic abnormality. EMH is most commonly seen in the liver and spleen but rarely has been reported in other locations, as well. On rare occasions, EMH may mimic a neoplasm in hematologically noncompromised patients. In this report, we present three cases of EMH in unusual locations, two in the presacral soft tissue and one in the synovial lining of the knee joint. The patients with presacral masses had no hematologic abnormality. In all patients with EMH, imaging plays an important role in both localization of the lesion and guidance for the biopsy; when imaging results are correlated with histological findings, the diagnosis of EMH can be confirmed.

Pathochemical and compensatory metabolic reactions were investigated in 30 patients with acute ischemic stroke. There were estimated blood concentration of malone dialdehyde and middle-mass endotoxic molecules and semicarbozide-sensitive amine oxidae activity. On the 5-7th days of the disease there were revealed significant increase of malone dialdehyde and middle-mass endotoxic molecules concentrations. In is possible to suppose that simultaneous changes of system semicarbozide-sensitive amine oxidae activity/ malone dialdehyde as a compensatory reaction directed to the support of metabolic homeostasis.

Several studies have tested whether narcissism is a compensatory reaction to underlying ego fragility by examining narcissism's empirical links to both explicit self-esteem (ESE) and implicit self-esteem (ISE), under the general expectation that narcissists should exhibit an abundance of ESE but a dearth of ISE. However, not only have these studies yielded conflicting findings, they have also proceeded from divergent theoretical assumptions that shape the interpretation of their findings. Here, we draw out the implications of three prominent models of the interrelationships between narcissism, ESE, and ISE, before reassessing those interrelationships in a large multi-session study. Two (out of three) indices of ISE covaried negatively with narcissism, consistent with the view that ISE is a global marker for ego fragility. We contextualize our findings in terms of recent research and propose a new mechanism linking ISE to ego fragility.

The external respiration parameters were studied in healthy workers of a chemical enterprise (246) and cadets of a police academy (82) for the normal state of the system of external respiration and under the conditions of an increased air content of the respiratory regions of the lungs. It was established that, in healthy subjects, an increased air content is a manifestation of the compensatory reaction of the external respiration system to long-term or regular hypoergosis. The reaction is aimed at increasing gas exchange in the lungs in cases where, for some reason, the oxygen demand of the body is not met completely.

The aim of this study was to determine correlation between parameters of proteolysis and phenotypes of α1-proteinase inhibitor in blood plasma of children with duodenal ulcer. Activation of kininogenesis, pepsin-and trypsin like proteinases was accompanied by the decrease in activity of α2-macroglobulin and the increase in activity of acid-stable inhibitors. Three subtypes of normal phenotype of α1-proteinase inhibitor (M1M3, M1M1, M2M2) were determined. Activation of proteolysis was more pronounced in the individuals with subtype M2M2. In M2M2 activity of α1-proteinase inhibitor was two times lower than in control, in M1M1 it insignificantly differed from control group and in the M1M3 subtype it was 1.9 times higher than in control. Low activity of α1-proteinase inhibitor seen at the M2M2 subtype was accompanied by higher activity of acid-stable inhibitors; this may be regarded as the protective compensatory reaction of the body. Determination of the α1-proteinase inhibitor phenotypes may be used for evaluation of a state of proteolysis and as a basis for employment of polyvalent proteinase inhibitors for therapy of ulcer.

Acute rat experiments have studied the impact of acute blood loss on the distribution of water fractions (total, free, and bound) in myocardial and hepatic tissues and whether detected impairments can be corrected by laser irradiation. They have provided an insight into the new pathogenetic mechanisms responsible for homeostatic disorders in blood loss and some aspects of the mechanism of action of laser emission on the body’s adaptive processes. The functioning of biopolymers and molecular structures in tissues is largely determined by their content of water. The redistribution of water towards to a blood loss-associated increase in bound water is a compensatory reaction aimed at preserving the biological structure of biopoly-mers. The decrease in hydrant-bound water suggests that there are severe derangements of their structure. The changes in the tissue free/bound water ratio reflect the degree of the body’s dysadaptation to blood loss. Laser irradiation has an adap-togenic effect on the structure of water in compensated hemorrhagic shock and a damaging action in decompensated one.

1. The effect on reaction time (RT) and anticipatory postural adjustment (APA) of unexpectedly changing stance conditions was studied using a push or pull arm movement task. The aim was to evaluate the modifiability of RT and APA by an external perturbation associated with an automatic compensatory reaction. 2. Subjects standing on a moveable platform were asked to push or pull a rigid handle as quickly and as strongly as possible in response to the 'go-signal', a visual signal from a green or red light-emitting diode. Forward and backward translations of the platform were randomly induced at four time intervals after the go-signal. In some experiments to detect unspecific arousal there were no platform translations but an acoustic signal was given before the go-signal. Surface electromyographic activity (EMG) of upper arm and lower leg muscles was analysed. 3. During the push task both RT and the duration of APA (onset of APA till the force signal indicating hand action) were shorter during backward than during forward translation. During the pull task the effect of platform translations was the reverse. The delay between go-signal and onset of APA remained constant. Consequently, RT and APA became shorter when the platform was translated in the same direction as that in which the upper body was displaced by the push or pull movement, and longer when it was translated in the opposite direction. The effects were maximal when translations were induced 250 ms after the go-signal, but a difference was detected up to 375 ms. 4. Furthermore, with forward and backward platform translations RT was shorter when the translations were induced early rather than late after the go-signal. This was associated with a shortening of the delay between the go-signal and onset of APA, while APA duration remained constant. The shortened RT was in the range of that obtained when an acoustic signal was given just before the go-signal. 5. It is concluded that (i) both the RT and the duration of APA can be modified by a translation of the support surface in a functionally appropriate way by updating the internal representation of the actual stance condition within the central nervous system. Both RT and APA are shortened when the body displacement induced by the push or pull movement and platform translation have the same direction; conversely, an inappropriate translation of the feet requires a greater APA and leads to a longer RT; (ii) both APA and RT are modifiable by platform translation for more than half the time between the go-signal and the focal push or pull movement; (iii) an unspecific effect of platform translation on RT can be identified; it may be mediated by a different neuronal substrate.

Proliferative processes in the gingival mucosa are studied by autoradiography in 55 patients with chronic gingivitis. It is found that the number of DNA-producing epithelial cells does not change. Increased label intensity in chronic catarrhal and hypertrophic gingivitis in comparison with the control testifies to a sufficient compensatory reaction. Regenerative processes are suppressed in chronic atrophic gingivitis. The number of pathological mitoses increases with the development of pathomorphological changes in all studied types of gingivitis.

Reversible changes in caudate neurons and their dendrites in line with the components of compensatory reaction in oligodendrocytes are observed in rats during the first 3 weeks of a 12-month alcoholization period. After 2–4 months of alcoholization (the development of dependency), degenerative changes occur in caudate neurons and their dendrites system were evident. By the end of the 12-month period of alcohol intoxication, intensified deafferentation of the dendritic system was observed, suggesting functional insufficiency of the caudate nucleus.

The purpose of this study is to clarify the mechanism of the adduction of ventricular folds during phonation. We assessed the type and degree of adduction of ventricular folds during phonation by fiber-stroboscopy in 277 cases of unilateral laryngeal nerve paralysis. In 169 cases of the 277 assessed, adduction of the ventricular folds occurred during phonation (61%), which was produced by the unaffected ventricular fold. Five cases (2%) exhibited adduction of the affected ventricular fold. There was no sex difference observed in the cases in which adduction of ventricular folds occured during phonation. As compared to nonadduction, the incidence of marked hyperadduction significantly increased with age in the later part of life. As for the maximum phonation time (MPT), the mean flow rate (MFR), and the SPL-range during the vocal function test, cases of marked hyperadduction of the ventricular folds showed significant reduction as compared with these with nonadduction. Regarding the pitch perturbation quotient (PPQ), the amplitude perturbation quotient (APQ) and the normalized noise energy (NNE) determined during the acoustic analysis, cases of marked hyperadduction of the ventricular folds showed significant reduction as compared with those of nonadduction. In many cases, reduction of the affected vocal fold function was observed in cases in which the fixed position of the vocal fold on the affected side was intermediate. In other words, the adduction of the ventricular folds was regarded as a compensatory reaction to glottal insufficiency. In 206 cases in which a silicon injection was performed, we compared the degree of adduction of the ventricular fold before and after the silicon injection. It is notable that following a silicon injection the degree of adduction was reduced in 106 (84%) out of the 126 cases in which adduction of ventricular folds was observed prior to injection., 国立情報学研究所で電子化

The purpose of this study is to clarify the mechanism of the adduction of ventricular folds during phonation. We assessed the type and degree of adduction of ventricular folds during phonation by fiber-stroboscopy in 277 cases of unilateral laryngeal nerve paralysis. In 169 cases of the 277 assessed, adduction of the ventricular folds occurred during phonation (61%), which was produced by the unaffected ventricular fold. Five cases (2%) exhibited adduction of the affected ventricular fold. There was no sex difference observed in the cases in which adduction of ventricular folds occured during phonation. As compared to nonadduction, the incidence of marked hyperadduction significantly increased with age in the later part of life. As for the maximum phonation time (MPT), the mean flow rate (MFR), and the SPL-range during the vocal function test, cases of marked hyperadduction of the ventricular folds showed significant reduction as compared with these with nonadduction. Regarding the pitch perturbation quotient (PPQ), the amplitude perturbation quotient (APQ) and the normalized noise energy (NNE) determined during the acoustic analysis, cases of marked hyperadduction of the ventricular folds showed significant reduction as compared with those of nonadduction. In many cases, reduction of the affected vocal fold function was observed in cases in which the fixed position of the vocal fold on the affected side was intermediate. In other words, the adduction of the ventricular folds was regarded as a compensatory reaction to glottal insufficiency. In 206 cases in which a silicon injection was performed, we compared the degree of adduction of the ventricular fold before and after the silicon injection. It is notable that following a silicon injection the degree of adduction was reduced in 106 (84%) out of the 126 cases in which adduction of ventricular folds was observed prior to injection., 国立情報学研究所で電子化

To study the functional state of the heart in a progressive increase of seizure readiness (SR) due to pentylenetetrazole kindling.The study was carried out on male rats of the Wistar line. Simultaneous telemetric monitoring of electrocardiogram and electroencephalogram on-line was used. Individual SR of animals in 7- and 27 day pentylenetetrazole kindling was determined.The decrease in the index of LF/HF after 7 days of kindling reflects a compensatory reaction of the autonomic nervous system. However, the increase in SI indicates that the result obtained at the price of considerable stress regulation mechanisms. The increase in QTc, Tpeak Tend and reduced SDNN and TP suggest that compensatory mechanisms cannot prevent the high risk of life-threatening arrhythmias. High SR after 27 days of kindling is accompanied by a shift of autonomic balance towards the growth of tone of the sympathetic system which may lead to decompensation and prenosological state.The characteristics of autonomic regulation of the heart in progressive SR are important for fundamental and clinical cardioneurology.Цель исследования. Изучить функциональное состояние сердца при прогрессирующем нарастании судорожной готовности (СГ), обусловленной пентилентетразоловым (ПТЗ) киндлингом. Материал и методы. Исследования проведены на крысах-самцах линии Вистар. Применяли следующие методы: синхронный телеметрический мониторинг электрокардио- и электроэнцефалограммы в режиме on line, определяли индивидуальную СГ животных при 7- и 27-суточном ПТЗ киндлинге. Результаты и заключение. Снижение индекса LF/HF после 7-суточного киндлинга отражает компенсаторную реакцию вегетативной нервной системы. Однако увеличение SI указывает на то, что достигнутый результат получен ценой значительного напряжения механизмов регуляции. Увеличение QTc, Tpeak Tend, а также снижение SDNN и TP свидетельствуют, что компенсаторные механизмы не могут предотвратить высокий риск возникновения жизнеугрожающих аритмий. Высокая СГ после 27-дневного киндлинга сопровождается смещением вегетативного баланса в сторону роста тонуса симпатической системы, что может привести к декомпенсации и донозологическому состоянию. Выявленные особенности вегетативной регуляции сердца при прогрессирующей СГ имеют значение для фундаментальной и клинической кардионеврологии.

A histophotometric study of the liver dehydrogenase activity reveals the nature of changes of enzymatic homeostasis and its periodicity in the dynamics of endotoxinemia in dogs. A compensatory reaction to lipopolysaccharide administration develops during the first two hours. A decrease of dehydrogenase and diaphorase activity and the development of structural damage to hepatocytes appear later. It is shown that the activation of free-radical oxidation as well as an increase of the level of medium-sized molecules in the blood plasma play a key role in the pathogenesis of liver damage.

Magnesium (Mg) is essentially an intracellular ion, which makes it difficult to evaluate Mg status. Both circulating total (MgT) and ionized Mg2+ (MgI) are used in clinical practice but their respective interest is still debated. In the present review, we list various s tudies comparing MgT and MgI in either Mg imbalances or Mg status dysregulations. In simple Mg imbalances (either therapeutic Mg overload or Mg defi ciency), the evaluation of MgT appears a better marker than MgI because it seems that a subtle physiological homeostatic compensatory reaction modifies the proportion of MgI, the most biologically active fraction of blood Mg, in order to reduce the effects of Mg imbalance. In contrast, in Mg dysregulations (either Mg pathological overload or Mg depletion) both fractions may vary independently, depending mainly on the renal status and on the equilibrium between MgI and Mg complexed with proteins and anions. The choice of the more appropriate marker is discussed.

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Calcium channel blockers can be classified into three main subgroups on the basis of their pharmacologic features. In earlier work the radioprotective effect of dilthiazem and nifedipine was proved, when these antagonists were given to mice s.c. or i.p. In this work mechanism of radioprotective activity was studied.

The aim of this study was to evaluate the degree of contribution of supraspinal input to the generation of the compensatory leg muscle activation following stance perturbation. Therefore, evoked motor response (EMR) input-output relations of two different motor tasks were compared at 3 distinct periods: (1) the basic period of muscular activity during standing, i.e. when no additional cortical or spinal activity due to the different tasks is to be expected, (2) the pre-movement period with low background activity, when different spinal and cortical inputs to the motoneuronal pool can be assumed and (3) the period of plateau EMG activity of compensatory and voluntary motor task. Transcranial magnetic stimulation (TMS) just below the motor threshold was applied randomly at 19 different time-intervals before and during the onset of stance perturbation and for comparison during an equivalent voluntary foot-dorsiflexion task. Recordings of electromyographic (EMG) activity from the tibialis anterior (TA) and corresponding ankle-joint movements were made from both legs. Forward-directed displacements were induced by randomly-timed ramp impulses of constant acceleration upon a moveable platform. For comparison, leg muscle EMG was recorded during isometric foot dorsiflexion during stance while leaning back against a support. The stance perturbations were followed by a compensatory response (CR) in the TA with a mean onset time of 81 ms. During the basic period of muscular activity and the period of plateau EMG activity there was no significant difference of the input-output relation between stance perturbation and the voluntary motor task. However, in the voluntary task compared with the CR, there was significantly greater input-output relation (facilitation) of the EMR in the TA following TMS, which may be related to an increased cortical influence. In contrast to this result of the CR following stance perturbation, a facilitation of the EMR was described for hand muscles under corresponding conditions of automatic compensation for muscle stretch, suggesting a transcortical reflex loop. This difference in the results from upper and lower extremity muscles favors the assumption of a predominantly spinal generation of the TA-CR following stance perturbation. Copyright (C) 1998 Elsevier Science Ireland Ltd.

It was suggested that the role of the cerebellum in locomotion includes a contribution to adjustments of the timing of locomotor movements of the limbs, an involvement in interlimb coordination and a modification of various reflex activities. In particular, it has been suggested that the cerebellum participates in the control of the sensitivity of muscle spindle stretch receptors through the fusimotor system (Gilman, 1969). However, Gorassini, Prochazka & Taylor (1993) have shown that the cerebellar nuclei (interpositus and dentate nuclei) are not primarily responsible for fusimotor control in cat locomotion.

Weaned wether goats ( n = 144) approximately 6 months of age were placed in a 2 × 3 factorial design experiment for 5 months to test the main effects and interaction of two levels of nutrition (growth+maintenance, NUT1; twice growth+maintenance, NUT2) and three levels of Haemonchus contortus burden (0, 500 and 2000 larvae administered every 2 weeks: W0, W500 and W2000, respectively) on weight, feed intake, level of infection and packed cell volume (PCV). The rationale for the experimental design was based on the lack of information concerning the interaction between nutritional status and worm burden. Results indicated significant effects of worm burden levels on PCV, faecal egg contents (eggs per gram of feces (EPG)), actual worm numbers, feed intake and efficiency of feed utilization. Nutrition×worm burden interactions were also significant for PCV and EPG. However, the differences detected for PCV and actual worm numbers did not translate into large or consistent differences in body weight. Goats on NUT2, after an initial period, showed little difference in body weight, irrespective of worm burden. Within the NUT1 level, W0 kids weighed more than W500 or W2000 kids throughout the study. Although not statistically significant, this constitutes a trend towards an interaction between nutrition and worm burden. In both nutrition levels, there were no body weight differences between W500 and W2000 until the last 14 days. Feed intake was depressed in the first 3 months of the experiment for infected animals, but was subsequently followed by a compensatory reaction. Lower establishment rates, based on actual worm counts, were observed for the higher infection level, but in both infection levels establishment rates tended to decrease with time. Nutrition was found to be more important to counteract the consequences of a parasitic infection than to counteract the establishment of that same infection.

Progesterone levels in peripheral blood were measured throughout the pseudopregnancy period by a competitive protein-binding technique in individual female (R × U) F1 hybrid rats. Rats made pseudopregnant by sterile copulation or electrical stimulation of the uterine cervix showed similar changes in progesterone levels during pseudopregnancy. Blood progesterone levels increased gradually from 3 µg/100 ml on day 0 (=day of vaginal cornification) until a plateau of 10 µg/100 ml was reached on day 5 of pseudopregnancy. After day 8 a very gradual decreased was observed which resulted in a level of about 2 µg/100 ml on days 14–15. In order to investigate a possible compensatory reaction of corpora lutea (CL) during pseudopregnancy progesterone levels were measured after unilateral ovariectomy (ULO) at various days of pseudopregnancy and after cauterization of CL on days 1 and 2 of pseudopregnancy. After ULO on day 0 the maximal progesterone levels remained low (5 µg/100 ml vs 9 µg/100 ml in sham-operated anima...

Habituation, the decline in response to a repeatedly presented stimulus, is found in a very wide variety of animals, and recent neurobiological analysis by Kandel and his colleagues has started to reveal the cellular changes responsible for these changes in behaviour, at least in invertebrates. But such analysis rests on a psychological theory which attributes habituation to a decline in the efficiency of transmission at some point in the pathway between stimulus and response. Such a theory seems to contrast with a comparator theory of habituation, first proposed by Sokolov and now accepted by many psychologists, according to which incoming stimuli are compared to the contents of memory and if they match are denied access to some further point in the system. The most detailed version of this theory is that proposed by Wagner, but the behavioural evidence thought to support Wagner's theory is found inadequate to do so, and a number of experiments directly contradict it. The only consistent support to be found for Wagner's account is that long-term habituation to biologically significant or potent stimuli (the development of tolerance to drugs is the best example) depends on an association between such a stimulus and the context in which it is repeatedly presented. This set of findings is best explained by supposing that long-term habituation to such potent stimuli, but not other instances of habituation, involves the conditioning to contextual stimuli of an opponent process or compensatory reaction which counteracts the initial responses elicited by the stimulus. This proposal is incorporated by Wagner into later versions of his theory, but is logically distinct from comparator theory. There is no good evidence to support a comparator theory of habituation, either in its general form or in Wagner's earlier version of it, and the only unique prediction which might be derived from this general class of theory is that habituation involves the ability to discriminate novel from familiar stimuli. Since the prediction is surely disconfirmed, comparator theory is either incorrect or no more than a redescription, in more fanciful language, of the stimulus-response theory of habituation.