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1.
Twelve poliovirus isolates of serotype 3 from patients with paralytic poliomyelitis have been analyzed by oligonucleotide mapping of the viral genomes. All the studied strains were isolated from patients in different regions of the Moldavian SSR in 1982. The maps of all isolates are similar but they do not practically possess any large oligonucleotides characteristic of the vaccine strain of type 3 poliovirus. It is concluded that a wild neurovirulent strain of type 3 poliovirus, that circulated in 1982 in the Moldavian SSR was the cause of paralytic poliomyelitis cases. All the studied isolates are suggested to have been derived relatively recently from the common ancestor.  相似文献   

2.
The etiological role of S. dysenteriae in Shigella infections at different territories of the USSR in 1983-1987 is analyzed. The study shows that S. dysenteriae pertain to territories with unfavorable water supply of the population. At some of these territories, in particular the Uzbek SSR, Grigor'ev-Shiga dysentery seems to gain ground and the restoration of the area of its spread occurs. In recent years the penetration of Grigor'ev-Shiga dysentery from abroad became more frequent in the presence of the pandemic of this dysentery in the world, which caused the appearance of the disease in 17 out of 27 basic territories of the All-Union Center of Shigella Infections. The ways for increasing the control of this infection are outlined.  相似文献   

3.
The medicinal resistance of Salmonella strains isolated on the territory of the Moldavian SSR in 1985 was studied. The greatest number of multiresistant microorganisms was shown to occur among S. java, S. virchow and S. infantis, i.e. the serovars dominating in the etiological structure of Salmonella infections on this territory. The seasonal distribution of cases of Salmonella infections and the age structure of patients with these infections induced by multiresistant strains and antibiotic-sensitive strains were found to have essential differences.  相似文献   

4.
The etiological structure of Salmonella infections and the biological properties of salmonellae, isolated in one of the regions of the Moldavian SSR where the epidemic process of Salmonella infections reflected the regularities observed on the whole territory of this republic, were studied. Changes in the predominant serovars at the period of 1982-1985 in comparison with the preceding years were shown. Salmonellae belonging to the dominating serovars were characterized by more pronounced drug resistance in comparison with other salmonellae. Some parameters of the epidemic process of Salmonella infections were found to be related to the biological properties of the causative agents of these diseases.  相似文献   

5.
A total of 300 blood serum samples, containing HBsAg and obtained from donors in three regions of the USSR (the RSFSR, the Uzbek SSR and the Moldavian SSR) differing in the level of HBsAg carriership, were studied for the presence of HBeAg and antibodies to this antigen in the passive hemagglutination (PHA) test and in the enzyme immunoassay (EIA). The occurrence of HBeAg was found to depend on the level of HBsAg carriership in the region. Thus, according to the EIA results, in Gorky, Kishinev and Tashkent HBeAg was detected, respectively, in 5.5%, 12.3% and 13.3% of serum samples, the level of HBsAg carriership in these cities being, according to the results of the PHA test, 1.4%, 5.0% and 9.0%. As shown by the results of EIA, the occurrence of HBeAg increased with the rise of the titer of HBsAg, while regarding the occurrence of antibodies to HBeAg the reverse relationship was observed.  相似文献   

6.
The authors conducted a prospective controlled epidemiological observation in two towns of the Moldavian SSR. There were 50 000 persons under observation. Over 300 000 parenteral manipulations carried out in them were recorded. Analysis of the materials obtained on the Minsk-22 computer demonstrated the same incidence of viral hepatitis in the groups given parenteral manipulations and without them. Consequently, the instrumental transmission factor had no essential significance in the epidemiology of viral hepatitis, this corresponding to the results of the authors' preceding theoretical study.  相似文献   

7.
Organochlorine pesticides disrupted reproduction and killed many raptorial birds, and contributed to population declines during the 1940s to 1970s. We sought to discern whether and to what extent territory occupancy and breeding success changed from the pesticide era to recent years in a resident population of Peregrine Falcons Falco peregrinus in southern Scotland using long‐term (1964–2015) field data and multi‐state, multi‐season occupancy models. Peregrine territories that were occupied with successful reproduction in one year were much more likely to be occupied and experience reproductive success in the following year, compared with those that were unoccupied or occupied by unsuccessful breeders in the previous year. Probability of territory occupancy differed between territories in the eastern and western parts of the study area, and varied over time. The probability of occupancy of territories that were unoccupied and those that were occupied with successful reproduction during the previous breeding season generally increased over time, whereas the probability of occupancy of territories that were occupied after failed reproduction decreased. The probability of reproductive success (conditional on occupancy) in territories that were occupied during the previous breeding season increased over time. Specifically, for territories that had been successful in the previous year, the probability of occupancy as well as reproductive success increased steadily over time; these probabilities were substantially higher in recent years than earlier, when the population was still exposed to direct or residual effects of organochlorine pesticides. These results are consistent with the hypothesis that progressive reduction, followed by a complete ban, in the use of organochlorine pesticides improved reproductive success of Peregrines in southern Scotland. Differences in the temporal pattern of probability of reproductive success between south‐eastern and south‐western Scotland suggest that the effect of organochlorine pesticides on Peregrine reproductive success and/or the recovery from pesticide effects varied geographically and was possibly affected by other factors such as persecution.  相似文献   

8.
The results of the study of the epidemiological regularities of viral hepatitis non-A, non-B with the fecal-oral mechanism of the transfer of infection in one of the regions of the Turkmenian SSR are presented. These results have been confirmed by serological and virological laboratory methods. The territories, groups of the population (age groups) and the time of the maximum epidemic risk of infection have been determined. The main (primary) role of the water route (polluted ground water) in the spread of this infection has been proved.  相似文献   

9.
The characteristic of distribution of Ukrainian lamprey Eudontomyzon mariae in the upper Don basin is presented. The examined part of the basin covers territories of Kursk, Orel, Tula, Ryazan, Lipetsk, Tambov, and Voronezh oblasts. It is shown that, at the present time in the upper Don basin, restoration of the range and an increase in the numbers of Ukrainian lamprey is occurring. The main concentrations of the species were recorded in the Don and Krasivaya Mecha rivers and their tributaries. In the basin of the Sosna River—one of the largest tributaries of the Don—Ukrainian lamprey is very widely distributed, but its population remains small and rarified. To preserve the species in the upper Don basin, it is suggested—in addition to already existing specially protected natural territories—to organize new ones in some small rivers and in the upper reaches of the Krasivaya Mecha River. In case of emergence of technogenic catastrophes, they can serve as donors for the entire basin of the upper Don.  相似文献   

10.
Samples of water, sediments and aquatic weeds were collected from 26 sites in the Nyando River catchment of the Lake Victoria basin in 2005–2006. The objective was to investigate levels of organochlorine pesticides that have either been banned or are restricted for use in Kenya. The pesticides investigated were lindane, aldrin, endosulfan, endrin, dieldrin, DDT, heptachlor and methoxychlor. These pesticides had previously found wide applications in public health and agriculture in Kenya for control of disease vectors and crop pests respectively. Results showed that mean concentrations were highest for methoxychlor (8.817 ± 0.020?µg l?1) in water, sediments (92.893 ± 3.039 µg kg?1), and weeds (39.641 ± 3.045?µg kg?1), the weeds also tended to accumulate aldrin (15.519 ± 3.756?µg kg?1). The results show that the pesticides are still in use and are detected in the catchment. Stringent management and public awareness measures are required to enforce the ban on the organochlorine pesticides in order to safeguard the environment and ecosystems of Lake Victoria.  相似文献   

11.
The characteristic of species composition of ichthyofauna of the upper Don basin, including data on moderate and small rivers, is provided for the first time. The examined part of the basin embraces territories of Tula, Ryazan, Lipetsk, Tambov, and Voronezh oblasts. A total of 51 species—66.7% of the total number of species recorded in water courses of the entire Don basin—were recorded in the ichthyofauna of the region. The decrease in the number of species in the upper Don basin as compared to its other sections proceeds mainly at the expense of marine and euryhaline species, as well as due to anadromous acipenserids. In this part of the basin, a smaller number of invading species was also recorded. However, Amur sleeper Perccottus glenii that was not discovered so far in other parts of the basin has dispersed here sufficiently widely. The wide distribution of bearded stone loach Barbatula barbatula and minnow Phoxinus phoxinus can be possibly also considered a distinguishing feature of fish population of the upper reaches of the Don in relation to other sites.  相似文献   

12.
A collection of 2178 local populations from ex-Yugoslavia territories is maintained in Maize Research Institute (MRI) gene bank. These populations were characterized mainly by morphological markers. In this work, 21 local populations belonging to seven different agro-ecological groups have been subjected to SSR analysis using a DNA-pooling strategy. The objective of this work was to develop genetic fingerprints for characterization, identification and classification of the populations, as well as for estimation of their genetic diversity. Also, a DNA-pooling strategy was employed with the aim to certify if it could be applied for population analysis with SSR markers. Statistical analysis of 25 informative SSR primers revealing 224 alleles (bands) showed that the average within-population mean number of alleles was 2.55, the average values for total and within-population diversity were 0.784 and 0.502, respectively, and G ST value was 0.360. Genetic distance values calculated using Modified Rogers Distance were in the range from 0.35 to 0.60. The silver staining method of DNA used for bulked samples showed some weakness that could be overcome with a more sensitive staining method. Nevertheless, the results in this work indicate that the SSR analysis of bulks could be used for characterizing a large number of populations in gene banks.  相似文献   

13.
Two sympatric species of Siberian loaches are recorded in the Zavkhan River basin (Great Lakes Depression, Western Mongolia) and described as new for science: Barbatula conilobus and B. dsapchynensis spp. n. The former species, most likely, is widely distributed over the entire river basin, and the latter species, apparently, occurs locally, but in sympatry with B. conilobus. Morphological differences of the new species from other representatives of the genus Barbatula and their relationships are analyzed. Ecological distinctions between the species of the genera Barbatula and Triplophysa in the Zavkhan River basin are described. Possible mechanisms of development of the present fauna of loaches in Mongolia and adjacent territories with an appearance of sympatric species pairs in a single water basin are discussed.  相似文献   

14.
Spontaneous activity of slow- and fast-adapted abdominal stretch receptor (SAR and FAR) of the crayfish and their activity evoked by adequate stimulation were investigated in the presence of efferent regulation. Activity of the receptors was shown to be under effective inhibitory control of two central neurons, principal and accessory; activity of these neurons, in turn, is determined by the current receptor activity. The closest interaction is found between SAR and the principal inhibitory neuron. Two types of efferent regulatory action of this neuron were discovered: grouped and continuous. Its powerful discharges (up to 361 spikes) arising in response to only one SAR afferent impulse are described. The character of synaptic connections between the peripheral and central neurons is discussed.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. Institute of Zoology, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Neirofiziologiya, Vol. 4, No. 3, pp. 317–327, May–June, 1972.  相似文献   

15.
Mechanisms of interaction between central and receptor neurons of the crayfish (the principal inhibitory neuron — PIN — and the slow-adapting stretch receptor — SAR) when functioning under different conditions were investigated: during regular spontaneous activity of SAR, grouped discharges of PIN, and regular spontaneous activity of PIN. A close connection was found between the various parameters of the PIN and SAR responses. Adaptation of SAR to the action of adequate, regular repetitive stimulation takes place faster in the presence of stationary background activity of PIN. The appearance and disappearance of SAR spike activity are determined by the ratio between the firing rates of SAR and PIN: at the moment of changeover the neuron with the higher firing rate is predominant.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. Institute of Zoology, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Neirofiziologiya, Vol. 4, No. 4, pp. 429–438, July–August, 1972.  相似文献   

16.
Appropriate environmental management of pesticides includes their proper application, use of filter strips and riparian buffers to contain pesticides in runoff from fields, prompt cleanup of spills, and treatment processes for wastewater associated with manufacturing and equipment usage. Plants have beneficial effects in the management of pesticide-contaminated soil and water, including direct metabolism of many pesticides, stimulation of microbial activity in the root zone, extraction of contaminated water, and reduction of infiltrating contaminated water. In this work, we review the literature on nontarget plants that can grow in pesticide-contaminated soil and water, and the fate of pesticides in filter strips, riparian buffers, and vegetated remediation environments. Past research indicates that there are significant differences in the tolerance of plants to pesticides present in soil and water, and that some plants are more effective than others in the remediation of pesticide-contaminated soil and water. Thus, there is value in the identification of tolerant plants and favorable plant-based remediation technologies for management of pesticides and contaminated sites.  相似文献   

17.
The Suquía River middle-lower basin (Córdoba, Argentina) is subjected to a strong anthropogenic impact because it receives pollutants from different sources. The main goal of this study was to evaluate the introduced fish species Gambusia affinis as a bioindicator of environmental pollution in the middle-lower basin of the Suquía River. The assessment was performed by measuring biomarkers at different levels of biological organization, at two sampling sites (before and after Córdoba city), and at dry and wet seasons. Water quality evaluation was made through a water-quality index (based on physico-chemical parameters), heavy-metals and pesticides concentrations in water. The water quality varied between sampling sites, showing the most degraded conditions downstream Córdoba city. The same pattern of variation was detected in the biomarkers studied, mainly in: gill and liver histopathological indexes, copulatory organ (gonopodium) morphology and vitellogenin expression in males and females. The present study characterized the environmental conditions in the middle-lower basin of the Suquía River and revealed the low freshwater quality at the most polluted site. Although G. affinis is an introduced species, it could be considered a good sentinel of water resource quality of invaded Neotropical basins. Our results demonstrated the importance of addressing the environmental quality monitoring through an integrated analysis of water quality parameters together with histological, morphological and molecular parameters. Thus, our study provides a good model for application in other basins of South America.  相似文献   

18.
The concept of territoriality proposed by E. Odum was used in this study. The territories were determined that were occupied by individuals of specific animal species and the notion territory of individual was proposed. The territories of individuals for different representatives of aquatic animals, including fish, were calculated and their relationships with mass and energy potential of animals were established. The territories of individuals and home ranges were compared in invertebrates and vertebrates. It was shown that for the entire animal world the relationship of these areas and mass can be described by a power equation with the exponent indistinguishable from 1. It was established on the example of zooplankton and zoobenthos communities that animal species with a larger size obtain advantage in the oligotrophic water bodies, since when the territories of individuals increase, they are capable of obtaining the necessary amount of food objects at their low density in such conditions. On the contrary, in the eutrophic water bodies, smaller animals have advantage, since they are capable of obtaining the necessary amount of food at a small home range and high density of food objects. A hypothesis was put forward that large and largest aquatic animals can occur in sea and oceanic waters not only because these are huge water basins, but also because these waters are, on the most part of territories, less productive, as compared to continental water bodies. In these conditions, the animals have to hunt over big territories for the necessary amount of food to be obtained and only large animals are able to do this.  相似文献   

19.
After 30 years of research, we begin to perceive an incipient outline of the Upper Palaeolithic in the central Ebro Valley. The assembled data permit us to speak of human occupation on the Southern face of the Pyrenees, but also on the borders of the Iberian Mountains and of the Ebro basin. All these sites seem to mark the passageways from and to the neighbour territories, emphasizing the communication pathway role of the Iberian basin.  相似文献   

20.
The characterization of etiological structure of Shigella infection in the whole of the USSR, in individual union republics and at a number of other administrative territories of the USSR in recent years is presented. S. flexneri has been shown to prevail at the territories with unsatisfactory water supply of the population, and S. sonnei prevails at the territories with good water supply. At the former territories S. dysenteriae and S. boydii retain their etiological importance, while at the latter ones their role is insignificant. At a number of territories the infectious process has stopped: no isolation of these shigellae from dysentery patients and carriers is observed any longer. Among the causative agents of Flexner's dysentery, S. flexneri 2a, 6 and 1b (in different combinations) play the leading role.  相似文献   

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