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11.
The ethylmorphine demethylase activity of the rat liver microsomes was higher in three-month animals (as compared to one-month), remained at a high level in the 12-month and decreased in old rats. The benzopyrene hydrolase activity increased in three-month animals, decreased in 12-month rats and remained the same with subsequent ageing of the organism. Asynchronicity of variations in the oxidation rate of different xenobiotics with ageing is considered as a result of changes in substrate specificity of the monooxygenase system due to metabolic peculiarities which reflect the age development of the organism and extinction of the reproduction function. 相似文献
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The paper describes a method for obtaining the antibiotic nisine from Streptococcus lactis str. MSU via 50% acetic acid extraction. The concentrate is dried in the Anhydro spray drier (Denmark). The preparation is inactivated during a one-year storage in the refrigerator by 20-25%. 相似文献
14.
Summary Work of the Genetic Consultation Group at the Institute of Medical Genetics, USSR Academy of Medical Sciences is analyzed and evaluated from the viewpoint of working out organizational principles for counseling. During three years (from July 1973 to June 1976) 1145 families were referred to us, of which 76% were referred by physicians and 24% were self-referrals.Reasons for referral were progeny prognosis (75.7%), health prognosis (1.5%), more precise diagnosis (18.1%), treatment (2.7%), and other reasons (2%). The main cause of referral was birth of a sick child (75%). People seeking advice were divided according to disease group as follows: chromosome diseases and congenital malformations (45.4%), monogenic diseases (15.4%), diseases with hereditary predisposition (14.6%), repeated miscarriages and infertility (11.5%), and others (13.1%).For counseling, 1145 families required additional cytogenetic (987) and biochemical (138) investigations. At evaluation of genetic risk, 16 types of genetic problems were encountered.It was concluded that genetic counseling should be organized firstly in pediatric and obstetric-gynecologic services, both in general and specialized hospitals. To facilitate referrals to the consultation center, spread of genetic knowledge among physicians and the population is necessary. The most effective form of propaganda among physicians is distribution of special literature with a list of indications for referral to consultation centers; most effective among the population are articles in newspapers and magazines. 相似文献
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N. A. Ushakova K. S. Laktionov A. A. Kozlova I. A. Ratnikova N. N. Gavrilova 《Biology Bulletin》2013,40(3):260-265
It was shown that the association of probiotic bacteria of the genuses Bacillus and Cellulomonas form biolayers on the surface of beet marc particles. The positive effect of a fodder additive that contained the biolayer on the basis of a phytomatrix on the growth and development of young rabbits was shown. Feeding of animals with a mixed fodder that contained 0.1% preparation resulted in stimulation of digestion of all components of the food. Among other components of the mixed fodder, cellulose was digested most effectively. An increase in the biomass of symbiotic bacteria and enzymatic activity in the blindgut chymus was also observed. The positive nitrogen balance demonstrated an increase in the nitrogen content in animals and a decrease of its losses with excretion. The mechanism of response of the rabbit’s organism to introduction of the complex probiotic preparation into the digestive tract is discussed. 相似文献
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Adameyko K. I. Kravchuk O. I. Finoshin A. D. Bonchuk A. N. Georgiev A. A. Mikhailov V. S. Gornostaev N. G. Mikhailov K. V. Bacheva A. V. Indeykina M. I. Bugrova A. E. Gazizova G. R. Kozlova O. S. Gusev O. A. Shagimardanova E. I. Lyupina Y. V. 《Molecular Biology》2020,54(3):416-420
Molecular Biology - The iron-containing protein neuroglobin (Ngb) involved in the transport of oxygen is generally considered the precursor of all animal globins. In this report, we studied the... 相似文献
18.
AV Shevchenko IG Budzanivska TP Shevchenko VP Polischuk D Spaar 《Archives Of Phytopathology And Plant Protection》2013,46(2):139-146
The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants. 相似文献
19.
N. G. Loiko L. I. Vorob’eva E. Yu. Khodzhaev A. N. Kozlova V. F. Gal’chenko G. I. El’-Registan 《Microbiology》2013,82(2):126-132
The effect of the extracellular peptide reactivating factor (RF) synthesized by Luteococcus casei on stress response of Escherichia coli cells subjected to UV irradiation was studied. For these studies, we constructed a test strain carrying the umuD-lacZ operon. The expression rate of this operon reflects the rate of SOS response. Protective effect of RF, defined as the number of cells retaining the colony-forming activity (CFU) after UV irradiation (49–1166 J/m2), was dose-dependent, species-nonspecific, and increasing with increase of the stress load. RF was demonstrated to possess the properties of a direct adaptogen: 15 min of preincubation with RF caused a 1.5–6-fold decrease in expression of the umuD SOS response gene in UV-treated cells, concurrently with a 1.2–7.5 times increase in the number of viable cells (those having retained their colony-forming activity). The probable mechanisms of the protective effect of RF are being discussed. 相似文献
20.
N. V. Potekhina A. S. Shashkov G. M. Streshinskaya E. M. Tul’skaya Yu. I. Kozlova S. N. Senchenkova E. B. Kudryashova L. I. Evtushenko 《Microbiology》2013,82(5):579-585
Cell walls of three type strains of the Bacillus subtilis group, Bacillus mojavensis VKM B-2650, Bacillus amyloliquefaciens subsp. amyloliquefaciens VKM B-2582, and Bacillus sonorensis VKM B-2652, are characterized by the individual set of teichoic acids. All strains contained 1,3-poly(glycerol phosphates), unsubstituted, acylated with D-alanine, and glycosylated. The latter differ in the nature of the monosaccharide residue. Teichoic acids of B. mojavensis VKM B-2650T and B. amyloliquefaciens subsp. amyloliquefaciens VKM B-2582T contained α-glucopyranose, while those of B. sonorensis VKM B-2652T contained β-glucopyranose and N-acetyl-α-D-glucosamine. Moreover, cell walls of B. mojavensis VKM B-2650T contained a teichoic acid of poly(glycosylglycerol phosphate) nature with the following structure of the repeating unit: -4)-α-D-α-D-GlcpNAc-(1 → 3)]-Glcp-(1 → 2)-sn-Gro-(3-P-. The type strains have been characterized according to the composition of cell wall sugars and polyols. Application of teichoic acids (set and structure) as chemotaxonomic characteristics is discussed for six type strains of the Bacillus subtilis group. Polymer structures were determined by chemical and NMR spectroscopic techniques. 相似文献