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The prevalence of hereditary autosomal dominant gastrointestinal adenomatosis in the Moscow population was estimated on the basis of elaboration of an indirect method. This estimate was found to be 1:48000. The prevalence observed is discussed in terms of ascertainment problems and peculiarities of the method of calculation proposed. 相似文献
105.
Iu P Nikitin M I Dushkin A V Dolgov I A Gordienko 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(8):162-164
Intraperitoneal injection of 25 micrograms/100 g body weight of 17 alpha-ethinyl estradiol to rats was shown to decrease serum cholesterol and to increase hepatic cholesterol. The rise in the level of non-labeled and C14-labeled free and esterified cholesterol in hepatic homogenate, as well as in lysosomal and cytosol fractions was accompanied by reduced activity of acyl-CoA-cholesterol acyltransferase and increased activity of lysosomal cholesterol esterase, as compared with the controls. The activity of cytoplasmic cholesterol esterase remained practically unchanged. Fistula bile of treated rats collected during 30 min was analyzed for the concentration of free cholesterol and bile acids. It has been shown that treatment of rats with 17 alpha-ethinyl estradiol caused an increase in hepatic cholesterol elimination via bile pathways. 相似文献
106.
The oligotrophic bacterium Ancylobacter vacuolatus contains two large plasmids pREV1 and pREV2 (about 150 and 250 kb, respectively). Plasmid pREV1 carries the genes responsible for resistance to chloramphenicol, trimethoprim and y-irradiation. Plasmid pREV2 carries the genes responsible for resistance to beta-lactam antibiotics and formation of gas vacuoles. The ability to grow under oligotrophic conditions did not depend directly on either plasmid and was probably chromosome-encoded. Nevertheless, strains lacking the pREV2 plasmid had an improved capacity for growth in enriched media, as is evident from the following findings: 1) the growth rate of the strains lacking pREV2 was about 60% higher with an induction time of about two times less than those for strains carrying the plasmid; 2) the overall cell yield in rich media and colony size on non-oligotrophic agarized media increased with removal of pREV2; 3) the characteristic change in cell morphology occurring in the wild type ofA. vacuolatus when switched from oligotrophic to eutrophic growth conditions was not observed in the strains lacking pREV2; 4) bacterial strains lacking pREV2 exhibited significantly higher rRNA content than the parent strain. As a possible explanation for these phenomena, we suggest that the pREV2 plasmid carries gene(s) for protein(s) acting as repressor(s) of expression of some enzymes involved in eutrophic metabolism. Such protein(s) probably participate in switching between the oligotrophic and eutrophic types of metabolism in response to changing nutrient supply in the environment. 相似文献
107.
Nikitin SV Kniazev SP Nikolaev AG Volokh AM Kirichenko AV Savina MA Ermolaev VI Iudina OP Bekenev VA Aĭtnazarov RB 《Genetika》2006,42(3):403-413
Variation of serum protein allotypes serving as genetic markers of the blood has been analyzed in 29 populations of the domestic pig and subspecies of the wild boar. The population biodiversity and genetic structure have been estimated by two methods: by the frequencies of allotype combinations and with the use of a map constructed in the space of two principal components. The results obtained are the basis for determining the characteristics of the microevolution of wild boars and formation of the breeds of domestic pigs. 相似文献
108.
Erofeev IuV Uskov PA Kriga AS Nikitin SV Vaĭtovich MA Burashnikova IP Anpilova NG Ukrainets NV Turchaninov DV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2006,(5):94-96
In article organizational aspects of carrying out preventive and antiepidemic actions at a regional level are considered at the bird's flu epizootia. Epizootic researches have shown, that infection of poultry has taken place as a result of contact to a wild bird. Serological inspection 521 persons on presence of antibodies to a influenza A (H5N1) has not revealed seropositive persons. The conclusion, that the forecast of development of a situation for spring of 2006 is made in view of a direction of migration of a wild waterfowl is unfavourable. 相似文献
109.
Bogacheva I. N. Nikitin O. A. Musienko P. E. Savokhin A. A. Gerasimenko Yu. P. 《Biophysics》2009,54(3):370-374
A study was made of the stepping pattern formation in decerebrated and in chronic spinal cats during epidural stimulation
(ES). The hindlimb stepping performance depended on the parameters of ES and afferent input. At non-optimal ES parameters,
no stepping was induced, only muscle reflexes followed the stimulation rhythm. Optimized ES (3–5 Hz, 50–100 μA for decerebrated
and 20–30 Hz, 150–250 μA for spinal cats) evoked coordinated stepping movements at a natural rate (0.8–1 Hz) accompanied by
electromyographic burst activity of the corresponding muscles. In decerebrated cats, the bursts are formed owing to modulation
of early responses and the late polysynaptic activity. In chronic spinal cats, this process is mainly due to amplitude modulation
of the early responses. Formation of the stepping pattern in decerebrated cats involves spinal interneurons responsible for
the polysynaptic activity, which allows its correction based on processing the afferent signals. Activation of this system
in chronic spinal cats can be realized by afferent stimulation alone, without ES. 相似文献
110.
Solntseva SV Nikitin VP 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2010,96(12):1212-1222
We have previously found two stages of amnesia evoked by disruption of memory reconsolidation with MK-801 (NMDA glutamate receptors antagonists) application in food aversion conditioned snails. Repeated conditioning restored the food aversion at early stage of amnesia development (<10 days), whereas repeated conditioning 10 days after MK-801 application did not restore the food aversion. In present work, amnesia was induced with MK-801/reminding 24 hours after food aversion conditioning, and antiamnestic effects of NMDA receptor glycine site agonist d-cycloserine were studied at early (3rd day) or late (12th day) stages of amnesia development. D-cycloserine injection and reminding restored memory only 3 days after amnesia induction whereas d-cycloserine injection without reminding was ineffective. D-cycloserine injection and reminding as well as repeated learning 12 days after amnesia induction were also ineffective in memory restoration. Thus, for the first time, it is revealed that NMDA receptor agonist d-cycloserine influences the memory restoration processes only at early but not the later stages of amnesia development. 相似文献