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Korshunov VM Potashnik LV Efimov BA Volodin NN Korshunova OV Gyr K Frei R Reber H Iéréndorzh D 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2001,(2):61-64
Intestinal microflora was studied in 3 groups of children; 55--living in Mongolia, 18--in Switzerland and 28--in Russia. Age of children of both sexual groups was 1.5-3 years. This study revealed that in none of these groups of clinically healthy children living in different regions and having different diet normal intestinal microflora corresponded to the standard considered to be the norm. The revision of norm criteria for normal intestinal microflora in children is recommended. 相似文献
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A. V. Alexeev 《Paleontological Journal》2009,43(3):277-281
A new jewel beetle genus, with one species (Cretofrontolina kzyldzharica gen. et sp. nov.) from the Upper Cretaceous of Kazakhstan is described based on a body; and three new species of the formal genus Metabuprestium are described based on isolated elytra: Metabuprestium sibiricum sp. nov. and M. arkagalense sp. nov. come from the Arkagala locality (Upper Cretaceous of Russia) and M. ichbogdense sp. nov. is from the Shar Tologoi locality (Lower Cretaceous of Mongolia). 相似文献
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The status of intestinal parasitic infections and seroprevalence of cystic echinococcosis in the inhabitants in Dornod and Selenge, Mongolia, was observed with stool and serum samples from 165 and 683 residents from August 9 to August 15, 2003. A total of 10 inhabitants (6.1%) were found to be infected with protozoan cysts or oocysts by stool examinations; 7, 1 and 2 cases with Entamoeba coli, Giardia lamblia and Cryptosporidium parvum, respectively. A total of 62 people (9.1%) revealed significantly high levels of specific antibodies against Echinococcus granulosus by enzyme-linked immunosorbent assay (ELISA). The surveyed areas are rural areas and the sanitized tab water is not available. There is a possibility of endemic transmission of water-borne protozoan diseases in these areas. The clinical echinococcosis is needed to be searched from the seropositive inhabitants. 相似文献
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Population analyses in water samples obtained from the chemocline of crenogenic, meromictic Lake Cadagno, Switzerland, in October for the years 1994 to 2003 were studied using in situ hybridization with specific probes. During this 10-year period, large shifts in abundance between purple and green sulfur bacteria and among different populations were obtained. Purple sulfur bacteria were the numerically most prominent phototrophic sulfur bacteria in samples obtained from 1994 to 2001, when they represented between 70 and 95% of the phototrophic sulfur bacteria. All populations of purple sulfur bacteria showed large fluctuations in time with populations belonging to the genus Lamprocystis being numerically much more important than those of the genera Chromatium and Thiocystis. Green sulfur bacteria were initially represented by Chlorobium phaeobacteroides but were replaced by Chlorobium clathratiforme by the end of the study. C. clathratiforme was the only green sulfur bacterium detected during the last 2 years of the analysis, when a shift in dominance from purple sulfur bacteria to green sulfur bacteria was observed in the chemocline. At this time, numbers of purple sulfur bacteria had decreased and those of green sulfur bacteria increased by about 1 order of magnitude and C. clathratiforme represented about 95% of the phototrophic sulfur bacteria. This major change in community structure in the chemocline was accompanied by changes in profiles of turbidity and photosynthetically available radiation, as well as for sulfide concentrations and light intensity. Overall, these findings suggest that a disruption of the chemocline in 2000 may have altered environmental niches and populations in subsequent years. 相似文献
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Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. 相似文献
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In any geographical area, surveys of the prevalence of intestinal helminths are necessary to suggest appropriate control measures. The aim of this study was to determine the prevalence of intestinal helminth infections in children of the Kashmir valley and to identify the risk factors. Stool samples were collected from 2256 children from rural as well as urban areas of the Kashmir valley. The samples were examined by simple smear and zinc sulphate concentration methods. Intensity of the infection was quantified by Stoll's egg-counting technique. Infection by at least one intestinal helminth was found in 71.18% of the sampled population. The prevalence of Ascaris lumbricoides was highest (68.30%), followed by Trichuris trichiura (27.92%), Enterobius vermicularis (12.67%) and Taenia saginata (4.60%). Light (57.1%) to moderate (42.8%) intensity of infection was observed for A. lumbricoides, while the majority of the infected children (92.3%) harboured a light intensity of infection for T. trichiura. The age group, rural or urban residence, type of water source, boiled or unboiled water, type of defecation site, level of personal hygiene and maternal education were associated with helminth infection. Adequate control measures are urgently needed to combat the high prevalence of intestinal helminths and risk factors in the children of Kashmir valley. 相似文献
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The summarizing data on new negative tendencies in the state of health of children and adolescents in Russia are presented. The two-fold increased proportion of children with chronic pathology and disability is noted. Special attention is drawn to a high level of child morbidity in diseases of respiratory organs, especially bronchial asthma. Measures ensuring the sanitary and hygienic safety of the child population in Russia, including improvements in the organization of nourishment, vaccinal prophylaxis, working out hygienic criteria and health-saving technologies, have been analyzed. Priorities in the work aimed at the liquidation of negative tendencies in the health of the child population in Russia have been determined. 相似文献
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E W Williams W A Hemmings 《Proceedings of the Royal Society of London. Series B, Containing papers of a Biological character. Royal Society (Great Britain)》1978,203(1151):177-189
The transport of immunoglobulin and ferritin across the intestinal mucosa of adult rats provides an excellent model for transcellular protein transport study. Intestinal uptake and transcellular transport have been extensively studied in the neonatal rat, but not to such an extent in the adult rat. The transport of 125I labelled bovine immunoglobulin G and ferritin was studied in 100 days old rats using intestinally administered proteins. Antigen was estimated in the tissues by reacting extracts against specific immune antiserum prepared in rats, and visualization studies were carried out by fluorescence microscopy and direct deposition autoradiography at electron microscopic level. From these studies, it can be seen that these proteins are taken up by the intestinal cells and transported, antigenically intact, across the barriers to the body organs. 相似文献
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Clemens Woda P. Jacob A. Ulanovsky I. Fiedler Y. Mokrov S. Rovny 《Radiation and environmental biophysics》2009,48(4):405-417
Recently discovered historical documents indicate that large releases of noble gases (mainly 41Ar and radioactive isotopes of Kr and Xe) from the Mayak Production Association (MPA) over the period from 1948 to 1956 may
have caused considerable external exposures of both, inhabitants of Ozyorsk and former inhabitants of villages at the upper
Techa River. To quantify this exposure, seven brick samples from three buildings in Ozyorsk, located 8–10 km north-northwest
from the radioactive gas release points, were taken. The absorbed dose in brick was measured in a depth interval of 3–13 mm
below the exposed surface of the bricks by means of the thermoluminescence (TL) and the optically stimulated luminescence
(OSL) method. Generally, luminescence properties using TL were more favorable for precise dose determination than using OSL,
but within their uncertainties the results from both methods agree well with each other. The absorbed dose due to natural
radiation was assessed and subtracted under the assumption of the bricks to be completely dry. The weighted average of the
anthropogenic dose for all samples measured by TL and OSL is 10 ± 9 and 1 ± 9 mGy, respectively. An upper limit for a possible
anthropogenic dose in brick that would not be detected due to the measurement uncertainties is estimated at 24 mGy. This corresponds
to an effective dose of about 21 mSv. A similar range of values is obtained in recently published dispersion calculations
that were based on reconstructed MPA releases. It is concluded that the release of radioactive noble gases from the radiochemical
and reactor plants at Mayak PA did not lead to a significant external exposure of the population of Ozyorsk. In addition,
the study demonstrates the detection limit for anthropogenic doses in ca. 60-year-old bricks to be about 24 mGy, if luminescence
methods are used. 相似文献
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Rubicz R Zlojutro M Sun G Spitsyn V Deka R Young KL Crawford MH 《Human biology; an international record of research》2010,82(5-6):719-736
The fishing community of Bering Island, located in the Russian Commander Islands off the Kamchatka Peninsula, was originally founded by a small number of Russian soldiers and merchants, along with Aleuts forcibly relocated from the western region of the Aleutian archipelago. The purpose of this study is to characterize the genetic variation of Bering Island inhabitants for autosomal, mitochondrial, and Y-chromosome DNA and classic genetic markers and to investigate the genetic impact of the 19th-century founding and subsequent demographic events on this heterogeneous community. Our results show a loss of diversity among maternal lineages in the Bering Aleut population, with fixation of mtDNA haplogroup D, as revealed by median-joining network analysis and mismatch differences. Conversely, paternal haplotypes exhibit an increase in diversity and the presence of a substantial number of non-Native lineages. Admixture results, based on autosomal STR data, indicate that parental contributions to the mixed Aleut population of Bering are approximately 60% Aleut and 40% Russian. Classic genetic markers show affinities between the Bering Island Aleuts and the other historically founded Aleut communities of St. Paul and St. George in the Pribilof Islands, Alaska. This study demonstrates that the opposing evolutionary forces of genetic drift and gene flow acted on the maternal and paternal lineages, respectively, to shape the genetic structure of the present-day inhabitants of Bering Island. 相似文献
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E. V. Yan 《Paleontological Journal》2012,46(6):589-600
Six new species of the genus Lasiosyne Tan et al., 2007, the type genus of the family Lasiosynidae Kirejtshuk et al., 2010, are described from Jurassic and Lower Cretaceous deposits of Mongolia and East Siberia: L. shartegiensis sp. nov., L. insculpta sp. nov., L. longitarsa sp. nov., L. cataphracta sp. nov., L. punctata sp. nov., and L. decora sp. nov. A modified diagnosis of the genus is proposed. 相似文献
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D. V. Solovyeva J. D. Paruk J. Tash S. L. Vartanayn G. K. Danilov V. V. Pospekhov D. C. Evers 《Contemporary Problems of Ecology》2017,10(6):621-631
Loons (family Gaviidae) breed in small ponds and lakes across Arctic landscapes and are high level predators in the lake ecosystems. As such, they may serve as sentinel species, warning humans of alterations in habitat and ecosystem integrity in a region that is undergoing vast change due to climate warming. Here, we characterized the abundance and habitat use of four arctic breeding species of loons in the plains and surrounding mountains of western Chukotka, Russia. Loon surveys were conducted on foot and by boat from 2009–2015. Loon species differed in their use of the four lacustrine habitat types within the study area. In yedoma habitat, the yellow-billed loon (Gavia. adamsii) was the most abundant (0.593 birds/km2); on fluvial plain habitat, Pacific loons (G. pacifica) outnumbered other loons (0.701 birds/km2); mountain valleys were inhabited similarly by pacifica (0.354 birds/km2) and red-throated loons (G.stellata; 0.307); and maritime tundra was used only by pacifica (1.13) and Arctic loons (G. arctica; 0.553). G. adamsii was not observed in mountain valleys or maritime tundra. Mountainous portions of rivers were predominantly occupied by stellata and pacifica, and lowland rivers by stellata, pacifica and arctica. There was a significant difference in the size of lakes occupied by the four congeners. The largest loon, adamsii, occupied the largest lakes (0.69 km2), 80% larger than lakes utilized by pacifica (0.39 km2) and arctica (0.38 km2), and 35 times larger than stellata (0.02 km2). Most lakes were occupied by a single loon species (125/162, 77.2%). 相似文献
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The effect of the administration of chitosan (CS) and chitooligosaccharides (COS) on rat fecal microbiota was analyzed in this study. The profile of total bacterial population was monitored during 3 weeks of CS or COS application using denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene amplicons. Quantitative PCR was used for monitoring possible changes in the levels of total bacteria and the levels of individual bacterial groups: Bifidobacteria, Clostridium leptum, Enterobacteriaceae, Lactobacillus–Streptococcus–Enterobacter, and Bacteroides–Prevotella. The DGGE profiles revealed a high complexity and individuality of each tested subject, and variations in the composition of band pattern were observed. CS or COS per os administration changed the profile and structure of the microbial ecosystem of the gastrointestinal tract of healthy rats. COS have, in most cases, an opposite effect compared with CS; only the Bacteroides–Prevotella bacterial group and Enterobacteriaceae were influenced in the same way. The Bifidobacteria group was not influenced by the administration CS and COS. 相似文献
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Annette Kainu Ari Lindqvist Seppo Sarna Bo Lundb?ck Anssi Sovij?rvi 《Respiratory research》2009,10(1):71