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21.
It has been experimentally established that cultivation of yeast cells in depleted, dietary or normal nutrient aqueous solutions enriched with ortho-H2O spin isomers is accompanied by an increase in the amount of carbon dioxide produced by the cells and an increase in their biomass. It has been revealed that the rate of metabolic processes and biological activity depends on the quality of nutrition and enhances in time in both nutrient solutions. In contrast, the reproductive function and the rate of cell division are insusceptible to the components of nutrition, but intensified in a solution enriched with ortho-H2O similar to retardation of aging. The observed effects are discussed in assumption that an increase of a portion of ortho-H2O molecules occurs in the neighborhood of water channels in the cell membrane that let through only monomers of H2O and determine the rate vicinity of metabolic processes.  相似文献   
22.
We tried to answer the question to what extent neurons in the tectum of the superior colliculus (SC) of the cat and in regions of the mesencephalic reticular formation (MRF) localized more ventrally are involved in the control of movements of the limbs. The impulse activity of neurons of the above-mentioned structures was recorded in animals performing targeted operated food-procuring movements by their forelimbs (pressing the pedal). As was found, neurons with impulse reactions correlating with forelimb movements are rather numerous in the SC and adjacent MRF, and there are several groups of neurons, whose impulse responses reached their maxima within different phases of the movements. These were neurons with peaks of the discharge frequency coinciding with the target-reaching movement, with the moment of touching the pedal, with pressing the pedal, and with the development of the muscle force counteracting the forced withdrawal of the limb toward the initial position. Such specific patterns of the responses of different neurons of the SC and neighboring MRF are indicative of a rather specific involvement of the above structures in the control of forelimb movements in cats. Neirofiziologiya/Neurophysiology, Vol. 39, No. 3, pp. 245–254, May–June, 2007.  相似文献   
23.
ZW Yin  S Nomura  LZ Li 《ZooKeys》2012,(205):45-57
The genus Sinotrisus Yin & Li, comprising four species, is redefined and revised. Members of Sinotrisus are often found with ants of the subfamily Formicinae, or in humid forest habitats. The type speciesand three new species are (re-)described and illustrated: Sinotrisus kishimotoi Yin & Nomura, sp. n. (China: Sichuan), Sinotrisus nomurai Yin, Li & Zhao (type species) (China: Zhejing), Sinotrisus sinensis Yin & Nomura, sp. n. (China: Sichuan) and Sinotrisus vietnamensis Yin & Nomura, sp. n. (Vietnam: Lai Chau). A key is included as an aid to distinguishing these species.  相似文献   
24.
The somatotropic axis, the control system for growth hormone (GH) secretion and its endogenous factors involved in the regulation of metabolism and energy partitioning, has promising potentials for producing economically valuable traits in farm animals. Here we investigated single nucleotide polymorphisms (SNPs) of the genes of factors involved in the somatotropic axis for growth hormone (GH1), growth hormone receptor (GHR), ghrelin (GHRL), insulin-like growth factor 1 (IGF-I) and leptin (LEP), using polymerase chain reaction–single-strand conformation polymorphism (PCR–SSCP) and DNA sequencing methods in 452 individual Mehraban sheep. A nonradioactive method to allow SSCP detection was used for genomic DNA and PCR amplification of six fragments: exons 4 and 5 of GH1; exon 10 of GH receptor (GHR); exon 1 of ghrelin (GHRL); exon 1 of insulin-like growth factor-I (IGF-I), and exon 3 of leptin (LEP). Polymorphisms were detected in five of the six PCR products. Two electrophoretic patterns were detected for GH1 exon 4. Five conformational patterns were detected for GH1 exon 5 and LEP exon 3, and three for IGF-I exon 1. Only GHR and GHRL were monomorphic. Changes in protein structures due to variable SNPs were also analyzed. The results suggest that Mehraban sheep, a major breed that is important for the animal industry in Middle East countries, has high genetic variability, opening interesting prospects for future selection programs and preservation strategies.  相似文献   
25.
The effects of detergents, trypsin, and bivalent metal ions on production of phosphatidic and lysophosphatidic acids by the action of phospholipase D (PLD) on lecithin and lysolecithin were studied. It was found that these reaction products and dodecyl sulfate ions activate PLD, whereas other anionic detergents are less effective. A protective effect of the functioning enzyme against its hydrolytic inactivation by trypsin was found. Bivalent metal ions can be arranged in the following sequence by their ability to activate PLD in the hydrolysis of lecithin and lysolecithin: Ca2+ > Sr2+ > Ba2+ > Mg2+. These results are considered in relation to a proposed mechanism of activation and functioning of PLD with the participation of clusters of phosphatidates and lysophosphatidates. Such Me2+-induced formation of rafts or microdomains from the products of hydrolysis of phospholipids can rationalize not only PLD activation and self-regulation, but also the action of this mechanism on other components and properties of biomembranes. PLD and other lipolytic enzymes can be classified as lateral vector enzymes.  相似文献   
26.
The Influence of gamma-radiation by dozes 1, 5, 10 and 20 kGy on enzyme activity of ordinary chemozem were studied. Dynamics of the restoration of the enzyme activity after the influence of gamma-radiation in model experiments in 3, 30, 90 and 180 days was investigated. The doze 1 kGy did no statistically significant influence on the investigated enzymes. Dehydrogenase is more radiosensitive enzyme than catalase. Values of the saccharase activity differed a significant variation so in most cases it has not been registered statistically significant changes. In 90-180 days of the incubation enzymes activity was restored up to control values. Dehydrogenase activity in 180 days in variants with dozes 10 and 20 kGy was restored up to a level of the control, over variants with dozes 1 and 5 kGy--is higher than the control over 78% and 23% accordingly. Saccharase activity in 180 days after the influence of gamma-radiation with a doze 20 kGy was on 61% lower than the control.  相似文献   
27.
A hydrogen bacterium strain, N34, and its oxygen-resistant segregant strain, Y38, were subjected to a taxonomical study. Since both strains were capable of N2-fixation, N2-fixing facultative hydrogen autotrophs listed in “Bergey’s Manual of Systematic Bacteriology” were used for comparison. Both strains produced a water-insoluble carotenoid pigment, zeaxanthin dirhamnoside, indicating that both should be classified into the genus Xanthobacter. Then, the differential characteristics of the two species of the genus Xanthobacter, X. autotrophicus and X. flavus, were investigated as to both strains. The vitamin requirement, the sensitivity to oxygen under autotrophic conditions, the inducibility of hydrogenase, the substrate range of carbohydrates and N2-fixing growth characteristics of both strains were almost completely opposite to those of X. flavus. Moreover, both strains coincided exactly with X. autotrophicus in morphological and other physiological characteristics. From these results both strains were identified as Xanthobacter autotrophicus.  相似文献   
28.
Structural changes in the regional popliteal lymph nodes have been studied in C57Bl/6 male mice at the peak of the reaction "graft-versus-host" to H-Y antigen. Morphological and morphometrical investigations have been carried out in three groups of males (10 animals in each group). The first group includes intact animals (the first control group). To the males of the second group (the second control group) lymphoid cells are inoculated from intact C57Bl/6 females. To the males of the third group (experimental group) lymphoid cells are inoculated from H-Y antigen immunized C57Bl/6 females (anti-H-Y effector lymphocytes). The popliteal lymph nodes of the male mice from the third group twice increase in their size comparing to those in the control (the first and the second groups). Miotic activity increases in them 4.5 times, amount of cellular blast forms in medullary cords--4 times and 10 times--in the light zone of the cortical substance. Ratio of macrophages and eosinophils in structural components of the lymph nodes studied changes; this is, evidently, connected with massive destructive progresses, that take place in the lymph nodes of the animals from the third group. The results of the morphological investigations are in agreement with the hypothesis suggested, explaining the mechanism of development of the regional reaction "graft-versus-host" to H-Y antigen, basing on idiotype-antiidiotype interaction (the idiotypic network in the immune system).  相似文献   
29.
Russian Journal of Bioorganic Chemistry - The activity of specific tyrosine protein kinases is known to be associated with the production of oncogenes. A specific inhibitor of tyrosine protein...  相似文献   
30.
Effect of three- and fivefold intramuscular injections of antibiotics oxytetracyclin hydrochloride and benzylpenicillin sodium (20 mg/kg) on immunophysiological status of juveniles of rainbow trout Parasalmo (=Oncorhynchus) mykiss (pathomorphological evaluation of internal organs, determination of the number of different types of leucocytes in the blood, and electrophoretic investigation of protein profile of the blood serum) was investigated. It was determined that both antibiotics cause neutropenia, removal of albumin fraction in the blood serum, and appearance of lipoid assemblages and different pathologies of internal organs. Taste attractiveness of oxytetracyclin hydrochloride, benzylpenicillin sodium, cefazolin-akos, and neomycin sulfate at the concentration in artificial food pellets of 1, 10, and 100 mg/ml was evaluated. It was determined that neomycin sulfate has more preferable taste for fishes, cefazolin-akos is less attractive, and reaction of fishes to oxytetracyclin hydrochloride and benzylpenicillin sodium depends on their concentration. The presence of two strongly different behavioral stereotypes of testing of food taste was confirmed.  相似文献   
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