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71.
One hundred and seven healthy full-term newborns were examined in this study. The cardiointer-valogram (CIG) was continuously recorded on the fifth to seventh day of life. An electropolygram (EPG) was recorded in 14 newborns along with the CIG and included the electroencephalogram, electrooculogram, electrocardiogram, and pneumogram. The functional state of the infants was continuously monitored, and calm or active wakefulness and active or calm sleep were distinguished using common criteria. Quantitative analysis of the sleep EPG was used to differentiate sleep phases by a standard method. The CIG was analyzed during orthodox (OS) and paradoxical (PS) sleep, and three different CIG types were distinguished by visual assessment and differential criteria established previously. The three types of CIG considerably differed in the structure and power spectrum of slow oscillations of R-R intervals, especially in the range from 0.04 to 0.15 Hz. The type I CIG was recorded during OS. At the end of this phase, the variability range increased while the amplitude of the mode and the tension index were reduced, indicating the type II CIG, with a duration of 3–4 min. All three CIG types were observed during PS; the type III CIG dominated, accounting for 58.3 ± 4.6% of the phase duration. A relationship was found between the CIG types and the cyclic organization of sleep, pointing to a difference in mechanisms regulating the heart rate in different functional states of the central nervous system in newborns.Translated from Fiziologiya Cheloveka, Vol. 31, No. 2, 2005, pp. 90–95.Original Russian Text Copyright © 2005 by Evsyukova, Kondrateva. 相似文献
72.
A. A. Skomarovsky A. V. Gusakov O. N. Okunev I. V. Solov’eva T. V. Bubnova E. G. Kondrat’eva A. P. Sinitsyn 《Applied Biochemistry and Microbiology》2005,41(2):182-184
Enzyme preparations were isolated from the culture liquid of five mutant strains of the cellulase producer Penicillium verruculosum. The hydrolytic activities of these preparations against unbleached eucalypt cellulose was compared to that of commercial preparations of Trichoderma reesei (T. longibrachiatum). In the majority of cases, P. verruculosum enzymes provided higher yields of reducing sugars (RSs) and glucose. A correlation was found between the yield of RSs and the avicelase activity of the preparations in the reaction mixture.Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 2, 2005, pp. 210–212.Original Russian Text Copyright © 2005 by Skomarovsky, Gusakov, Okunev, Soloveva, Bubnova, Kondrateva, Sinitsyn. 相似文献
73.
We conducted a lifetime study of the content of oxidized and methylated guanine in the urine of intact and irradiated mice.
For statistical processing of the results, we used the trial period method created by A.A. Konradov, which was unpublished
during the author’s lifetime. We prove that there are oscillating components in the age dependence of the concentration of
oxidized and methylated guanine in mice urine. For intact animals, a 7-month oscillation period is the most probable (p = 0.001). For irradiated mice, a disruption in the seasonal oscillation rhythm in the concentration of oxidized and methylated
guanine in urine was noted, which is peculiar to radiation-accelerated aging. 相似文献
74.
Davidova VN Naberezhnykh GA Yermak IM Gorbach VI Solov'eva TF 《Biochemistry. Biokhimii?a》2006,71(3):332-339
The interaction of endotoxins--lipopolysaccharides (LPS) different in degree of the O-specific chain polymerization--with 20- and 130-kD chitosan was studied using the competitive binding of LPS with the complex of chitosan-anionic dye (tropaeolin 000-2) and the direct binding of (125)I-labeled LPS with chitosan immobilized on Sepharose 4B. The interaction of 20-kD chitosan with LPS was non-cooperative, and immobilization of the polycation on Sepharose resulted in its binding to (125)I-labeled LPS with a positive cooperativity. The interaction of LPS possessing a long O-specific chain with 130-kD chitosan was characterized by negative cooperativity. Binding constants of LPS with the polycation and the number of binding sites per amino group of chitosan were determined. The interaction affinity and stoichiometry of the LPS-chitosan complexes significantly depend on the LPS structure and concentration in the reaction mixture. The increase in the length of carbohydrate chains of LPS results in increase in the binding constants and decrease in the bound endotoxin amount. 相似文献
75.
A. P. Isaev V. K. Vasil’eva Z. Z. Borisov I. M. Okhlopkov 《Contemporary Problems of Ecology》2012,5(1):85-91
Original materials on the fauna of the northern macroslope of the Sette-Daban Mountain Ridge are presented. Birds and mammals
population in different habitats in the basin of the Allakh-Yun River are characterized. 相似文献
76.
V. N. Zinov’eva I. N. Iezhitsa A. A. Spasov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(2):133-147
Mechanisms of magnesium homeostasis intensively studied over the last 10–15 years by means of pathophysiological and molecular genetic approaches have been considered. Impairments of magnesium homeostasis causes the development of magnesium-deficient states, which have been found in many common diseases (diabetes mellitus, cardiovascular diseases, chronic fatigue syndrome, alcoholism, psychiatric and neurologic diseases, etc.), stress condition, effects of some environmental factors as well as therapy with some drugs. Special attention is paid to familial hypomagnesemias caused by genetic defects of magnesium transport systems. The review considers clinical and biochemical characteristics of twelve familial disorders including mechanisms of their development. Deeper understanding of mechanisms of regulation of magnesium homeostasis will results in the development of new approaches in diagnostics, prophylaxis and treatment of magnesium-deficient conditions. 相似文献
77.
T. N. Borodina L. D. Rumsh S. M. Kunizhev G. B. Sukhorukov G. N. Vorozhtsov B. M. Feldman A. V. Rusanova T. V. Vasil’eva S. M. Strukova E. A. Markvicheva 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(2):176-182
The microcapsules with entrapped herbal water-soluble extracts of plantain Plantago major and calendula Calendula officinalis L. (PCE) were prepared by layer-by-layer (LbL)-adsorption of carrageenan and oligochitosan onto CaCO3 microparticles with their subsequent dissolving after the treatment of EDTA. Entrapment of PCE was performed by using adsorption and co-precipitation techniques. The co-precipitation provided better entrapment of PCE into the carbonate matrix compared to adsorption. In vitro release kinetics (AGJ) was studied using artificial gastric juice. Using the model of acetate ulcer in rats it has been demonstrated that PCE released from the microcapsules accelerates gastric tissue repair. 相似文献
78.
79.
O. V. Avercheva E. M. Bassarskaya T. V. Zhigalova Yu. A. Berkovich S. O. Smolyanina M. R. Leont’eva A. N. Erokhin 《Russian Journal of Plant Physiology》2010,57(3):382-391
Leaf mesostructure, photochemical activity, and chloroplast photophosphorylation (PP) in the fourth true leaf of 28-day-old
Chinese cabbage (Brassica chinensis L.) plants were investigated. Plants were grown under a light source based on red (650 nm) and blue (470 nm) light-emitting
diodes (LED) with red/blue photon flux ratio of 7: 1 and under illumination with high-pressure sodium lamp (HPSL) at photon
flux densities of 391 ± 24 μmol/(m2 s) (“normal irradiance”) and 107 ± 9 μmol/(m2 s) (“low irradiance”) in photosynthetically active range. At normal irradiance, the leaf area in plants grown under HPSL
was twofold higher than in LED-illuminated plants; other parameters of leaf mesostructure were little affected by spectral
quality of incident light. The lowering of growth irradiance reduced the majority of leaf mesostructure parameters in plants
grown under illumination with HPSL, whereas in LED-illuminated plants the lowered irradiance reduced only specific leaf weight
but increased the leaf thickness and dimensions of mesophyll cells and chloroplasts. The photochemical activity of isolated
chloroplasts was almost independent of growth irradiance and light spectral quality. Light quality and intensity used for
plant growing had a considerable impact on PP in chloroplasts. At normal light intensity, the highest activity of noncyclic
PP in chloroplasts was observed for plants grown under HPSL; at low light intensity the highest rates of PP were noted for
plants grown under LED. The P/2e− ratio, which characterizes the degree of PP coupling to electron transport in the chloroplast electron transport chain, showed
a similar pattern. Thus, the narrow-band spectrum of the light source had little influence on leaf mesostructure and electron
transport rates. However, this spectrum significantly affected the chloroplast PP activity. The PP patterns at low and normal
light intensities were opposite for plants grown under LED and HPSL light sources. We suppose that growing plants under LED
array at normal light intensity disturbed the chloroplast coupling system, thus preventing the effective use of light energy
for ATP synthesis. At low light intensity, chloroplast PP activity was significantly higher under LED illumination, but plant
growth was suppressed because of impaired adaptation to low light intensity. 相似文献
80.
Some quantitative characters of three-summer old reciprocal hybrids of beluga Acipenser huso and starred sturgeon A. stellatus,as well as of juveniles of their parental species, are comparatively analyzed. The found maternal and paternal effects in
manifestation of some characteristics in hybrids are considered in connection with elucidation of inheritance type of morphological
characters in acipenserids. The paternal effect observed by some characters in hybrids beluga × starred sturgeon is explained
by prevalence of dominant alleles in the genome of starred sturgeon in comparison with beluga. The maternal effect is elucidated
by a few characteristics related to parameters of the head, first of all to the volume of the brain region of skull. Evidently,
in this case, the matrocliny depends on the fact that information on the number of segments of embryo and their position is
determined by the maternal organism during oogenesis. 相似文献