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1.
The retrospective and operative epidemiological analysis of leptospirosis morbidity on the administrative territories of the Southern Federal District during the period of 1990-2002 was carried out. The dynamics and tendencies of morbidity in individual administrative units of the region were shown. Materials on the negative influence of the emergency situation arising in the region as the result of the natural calamity in summer 2002 were presented. As shown in this work, timely decisions on the stabilization of epidemiological situation taken at the period of high flood and inundation in summer 2002 in the Southern Federal District and their efficient execution made it possible to keep the epidemiological situation in leptospirosis under control.  相似文献   

2.
Seroepidemiological study of hepatitis A (HA) morbidity was carried out in three Russian cities, with different levels of HA morbidity. The study included the analysis of HA morbidity for 22 years, the determination of antibodies to HA virus (anti-HAV) in 2,958 healthy persons aged 0-12 months to 40 years and older. In one of the cities 7 isolates of HA virus were obtained from unrelated sources and the genotypes of the virus were determined. The study revealed that the frequency of seropositive cases among persons of different ages correlated with the level and prolonged dynamics of HA morbidity. According to the occurrence of anti-HAV, such cities as St. Petersburg, Rostov-on-Don and Yakutsk may be at present classified as territories, moderately endemic in HA. At the same time in the 90 s the epidemic situation in HA was more favorable in Rostov-on-Don than in two other cities. The suggestion was made that a high proportion of seropositive persons among the population of St. Perersburg was linked with an almost twofold rise in HA morbidity in 1993-1995 caused by genotype 1 of the virus. Seroepidemiological studies in HA during the period of a drop in morbidity acquire special importance in the surveillance and control system of this infection.  相似文献   

3.
Cancer morbidity and mortality were studied in areas of the Kaluga oblast contaminated with radionuclides. The main objective of the study was to assess the influence of radiation exposure on existing levels of cancer morbidity and mortality. Time trends and relative population risks were analysed. Based on this analysis, it was concluded that the current levels of morbidity from cancers among the populations residing in the studied areas were primarily a result of a complex of factors which predated the exposure from the Chernobyl accident. However, there seems to be an unfavourable trend concerning malignant neoplasms of the respiratory organs for women residing in the contaminated areas. To date, no statistically significant effect of radiation on cancer morbidity (except for thyroid cancer in women) has been noted. The levels of cancer morbidity and mortality in the contaminated areas generally reflect the changes in cancer incidence in the oblast as a whole. The findings are consistent with international data on latent periods for the induction of radiogenic cancers and the biological effects for similar levels of exposure to populations residing in contaminated territories. Further studies are necessary in order to monitor possible effects that are related to the accident.  相似文献   

4.
A new method for estimation of EEG synchronism based on the analysis of correlation between amplitude modulation processes (envelopes) is considered. The efficiency of the given method is shown in different aspects: for detection of a topographical pattern, for analysis in frequency domains, for estimation of stability of the functional state and its changes, for detection of heterogeneous subgroups of subjects and outliers, for analysis of individual and group distinctions and distinctions in synchronism between symmetrical pairs of leads and hemispheric asymmetry, and for classifying division between mentally healthy subjects and deviations of schizophrenic spectrum with reliability approaching 100%.  相似文献   

5.
The hepatitis morbidity data were used to study prevalence rate of manifest viral hepatitis among the hospital staff members in CSR over a 3-year period between 1980 and 1982. This study showed that the overall hepatitis morbidity rate was 2.68 per 1,000 health personnel and was 3.6 times as high as that recorded in a normal population matched by age. The mean HBsAg positivity rate was 1.67 per 1,000 and was 5.8 times the rate in the control population group. The rate of HBsAg-negative cases of hepatitis was 1.01 per 1,000 health personnel and was higher than double the rate of morbidity encountered in an age-matched normal population. The highest morbidity rates were recorded in the lower-grade and auxiliary health personnel. When compared with an age-matched normal population the hospital staff members at all departments had distinctly higher morbidity rates than the general population, but the highest risk of acquiring viral hepatitis was evidently run by the personnel at departments of renal dialysis, biochemistry, hematology, infectious diseases, internal medicine, surgery, urology and TRD (tuberculosis and respiratory diseases). Of a total number of recorded cases of viral hepatitis those with HBsAg positivity predominated, especially at departments of urology, TRD, internal medicine, renal dialysis, psychiatry and hematology. Analyzed by specialty and professional status of personnel these viral hepatitis morbidity rates encountered among the hospital staff members seem to point to at least two conclusions: this infection in the health personnel is work-related and its transmission and spread is dependent on the frequency and intensity of contact with the blood and other secretions of infectious patients.  相似文献   

6.
Different forms of dysentery, especially those caused by Sh. sonnei and Sh. flexneri, have been found to differ considerably in their cyclic recurrence. The development cycles of the epidemic processes of dysentery have an objective character, occur in the presence of any tendencies in the morbidity rate, and depend on the natural factors. Thus, the cycles of increase and decrease in morbidity are 3, 6, 9, 12 years for dysentery caused by Sh. sonnei and 6, 7, 8 years for dysentery caused by Sh. flexneri.  相似文献   

7.
Data and tendencies characteristic of relationship between the severity of the course of tick-borne encephalitis and a number of biotic and climatic factors have been revealed by the method of information analysis. On the basis of relationships established in this study the authors make a suggestion concerning two most important stages in the formation and manifestation of the clinical features of tick-borne encephalitis in different areas of endemic territories, linked, on one hand, with the population selection of the infective agent and, on the other hand, with temperature conditions and the duration of the cold season.  相似文献   

8.
Using time-lapse microscopy, spreading of the post-mitotic daughter cells has been studied. The work was performed on non-synchronized cells of established L-929 cell line. The study was aimed to characterize the morphology of the cells as they move along the substrate and to determine whether the area of the migrating cells changes nonrandom. Two new parameters have been proposed for comparison of cell morphology: the identity indicator (II) and the synchronism indicator (SI). Time-dependent changes in the area in pairs of cells were measured to calculate these parameters. The first indicator shows the degree of coincidence between the absolute values of the area in the pair of the cells, whereas the second indicator shows synchronism of the changes in the cell areas and does not depend on their absolute values. The lower are the indicators, the higher is the similarity in the time-dependent changes in the areas of cell pairs studied. The indicators were shown to be approximately 1.5-fold lower for the pairs of the post-mitotic daughter cells than those for any other pair of the cells. The results indicate a nonrandom pattern of change in the morphology of the cells during their movement along the substrate.  相似文献   

9.
The epidemiological peculiarities of viral hepatitis in the Estonial SSR as a whole, as well as in Tallinn and in the surrounding Harju region were studied. The study revealed that during the last 10 years the total decrease of morbidity in viral hepatitis was observed due to a decrease in infectious hepatitis, pronounced periodic and seasonal morbidity fluctuations being absent. A sharp decrease in infectious hepatitis morbidity had been achieved by carrying out planned gamma globulin prophylaxis among children. Viral hepatitis morbidity in the republic was determined by the adult population and manifested as sporadic cases of infectious and serum hepatitis. Infectious hepatitis was transmitted mainly through every day contacts, while the leading factor in the transmission of serum hepatitis consisted in various injections. The relatively high morbidity level of serum hepatitis was mainly determined by morbidity in large cities.  相似文献   

10.
In this work materials characterizing the appearance and development of influenza epidemic at the territories of the USSR and the Czech Socialist Republic are presented, the common features and differences of the epidemic process in both countries are recorded. The work shows that in both countries the appearance of this epidemic is caused by the same virus. In most cases the epidemic started earlier and lasted longer in the USSR, but morbidity rate during the epidemic was, on the whole, higher in the Czech Socialist Republic. Similarity in the course of the primary period of the epidemic processes from their appearance to their maximum rise was observed. In both countries the maximum rise of morbidity rate was registered on weeks 3-4 from the beginning of the epidemic.  相似文献   

11.
Determinants of territory size in the pomacentrid reef fish,Parma victoriae   总被引:4,自引:0,他引:4  
Summary Factors governing the size of territories defended by the pomacentrid reef fish, Parma victoriae, were investigated, prompted by contradictory predictions in the literature concerning the effects of food supply and competitors. Observations were carried out over the non-breeding period (March–October) on a medium density population in which territories were partially contiguous. The territory size of adult fish varied between 3 and 26 m2, and was inversely correlated with local densities of conspecifics. The same range in territory size was found for both males and females, which did not differ in the time they spent on territory defence and foraging activities. No correlation existed between territory size and the abundance of algal food, body size, age or time spent on territory defence. Also, there was little variation in territory size over time, despite seasonal changes in the abundance of food algae.Experimental reduction of food supplies on isolated territories of males and females had no effect on territory size. In a higher density habitat an experiment was carried out in which population density and food abundance were simultaneously manipulated. This showed that territory size was primarily determined by intraspecific interactions, as territories exhibited considerable increases in size upon removal of neighbours. No changes in the size of defended areas resulted from either artificial increases or decreases of food levels. There were also no changes in the time spent on defence of territories, foraging time or feeding rates associated with food manipulations or territory expansion, which suggested that food was not a limited resource. This conflicted with current theories proposed to explain territory defence and expansion. It is hypothesized that intraspecific interactions constrain territory size well below the optimum in terms of the abundance of preferred food algal species.  相似文献   

12.
In this work the dynamics and morbidity level in respect of meningococcal infection at 11 territories of the RSFSR at the period of 1969-1984 are analyzed. The study covered altogether 16 cities and 211 districts. The role of big cities as the sources of infection spreading into rural areas and further "fixation" of this infection mainly in regions with a population of 60,000 and more had been established. The data on meningococcal morbidity and carriership among different age groups are presented. The study has shown a pronounced increase in the incidence rate of meningococcal infection among children aged up to 2 years, as well as an increase in the proportion of these children among patients with meningococcal infection in recent years.  相似文献   

13.
Females may use condition-dependent sexual traits as reliable cues of male “quality” if the costs of the expression of such traits vary with male “quality”, and if there is positive genetic correlation between male traits and condition. However, there are multiple ways of measuring the changes in body condition which reflect physiological costs meaning that the multifaceted nature of the physiological costs associated with the expression of sexual traits has rarely been thoroughly examined. In the lekking black grouse (Tetrao tetrix), mating success is highly skewed towards males defending central territories and having high survival rates to the following year, but the mechanisms underpinning such superior performance remain unclear. In this study, we quantified the changes in five measures of body condition before and after the mating season and related these changes to male lek performance (fighting rate, territory centrality and mating success) to understand the physiological costs of male reproductive effort. Between the two capture sessions, male body mass decreased significantly, blood parasite counts and plasma carotenoid concentration increased substantially while the total immunoglobulin concentration tended to increase. There was no overall impairment of individual body condition as the changes in the five measures of body condition were unrelated. Male fighting rate was unrelated to changes in the condition measures but males losing more body mass defended central territories and had high mating success. Therefore, females preferring central, dominant males may select males better able to afford the energetic costs of lek performance thereby effectively enforcing the honesty of male display.  相似文献   

14.
The study of the time course of typhoid-paratyphoid infections in the Chimkent region for the period of 1944-1979 has revealed the periodicity of their rises (falls) repeating every 2-4 years. Since 1964 the tendency towards the decrease of morbidity has been observed. The annual rate of this decrease is 4.9%. Periodic changes in the annual level of typhoid-paratyphoid infections do not depend on the temperature of the air and the seasonal number of winged flies. There is a pronounced direct correlation between the annual morbidity level and the frequency of summer precipitations, this correlation being more pronounced during the first 2 summer months.  相似文献   

15.
The libellulid dragonfly Paltothemis lineatipes exhibits annual variation in male mate-locating behaviour, variation that appears to be related to changes in the number of males competing in an area. In a year when males were numerous, as reflected in a high rate of male-male interactions, individuals defended small streamside territories, regularly raided neighbouring territories in an attempt to steal females there, and often were forced off their territory after a few hours of daily ownership. In this year, temporal partitioning of a given site was common, with the same males taking it in turns to defend the location for part of each day. In a year when males were much less numerous, as seen in a very reduced rate of aggressive encounters, males defended territories more than twice as large on average than in the high-density year; they rarely took females from neighbours, and they much less frequently 'shared' ownership of a site with another male on a given day. The changes between low- and high-density years were not associated with a change in average daily copulatory success of territorial males, although the variance in mating success was significantly greater in the high-density year.  相似文献   

16.
Abstract

Close monitoring of the lepidopteran leafroller Cnephasia jactatana under laboratory colonisation revealed few distinct effects of successive rearing on artificial diet on the life cycle. The second laboratory generation had a prolonged development time and altered sex synchronism in pupation and eclosion patterns. Some deleterious changes were observed in later generations, including decreases in fertility, egg hatch and sperm motility, failure of mating adults to separate, and pupal and adult malformations. These changes were not adaptive, but were due to incompatibility with the general purpose diet (GPD) used; they were absent under sub-colonisation on a sheepnut-bean based diet (SBD). Success in the laboratory colonisation of C. jactatana is attributed to a random mating protocol, choice of environmental conditions representing the wild habitat, and a rapid rate of population growth.  相似文献   

17.
Acute respiratory tract infections (ARTIs) are associated with significant morbidity and mortality worldwide, especially in children under the age of 5 years. Almost 2 million children die from ARTIs each year, and most of them are from developing countries. The prevalence and correlation of pathogens in ARTIs are poorly understood, but are critical for improving case prevention, treatment, and management. In this study, we investigated the prevalence and correlation of infectious agents in children with ARTIs. A total of 39,756 children with one or more symptoms, including fever, cough, sore throat, tonsillitis, pharyngitis, herpangina, pneumonia, and bronchiolitis, were enrolled in the study. All patients were hospitalized in Wuhan Children’s Hospital between October 1, 2010 and September 30, 2012, and were evaluated for infectious agents. Pathogens, including Mycoplasma pneumoniae, influenza A virus, influenza B virus, adenoviruses, respiratory syncytial virus, parainfluenza virus, Legionella pneumophila, Chlamydophila pneumoniae, and Coxiella burnetii, were screened simultaneously in patient blood samples using anti-pathogen IgM tests. Regression analysis was used to reveal correlations among the pathogens. Our results showed that one or more pathogens were identified in 10,206 patients, and that Mycoplasma pneumoniae, adenoviruses, and influenza B virus were the leading infectious agents. Mixed-infections of pathogens were detected in 2,391 cases, with Mycoplasma pneumoniae as the most frequent pathogen. The most common agents in the co-infections were Mycoplasma pneumoniae and influenza B virus. Regression analysis revealed a linear correlation between the proportion of mixed infections and the incidence of multi-pathogen infections. The prevalence of infectious agents in children with ARTIs was determined. Equations were established to estimate multiple infections by single-pathogen detection. This revealed a linear correlation for pathogens in children with ARTIs. This study provides useful information for improving case prevention and management.  相似文献   

18.
The possibility of the retrospective epidemiological diagnosis of viral hepatitis non A, non B with the fecal-oral mechanism of the transfer of infection in three cities of Central Asia on the basis of the analysis of the dynamics of registered hepatitis A morbidity is shown. With the irregularity of morbidity levels among the total population being characteristic of all three cities, in Andizhan one rise in morbidity within a period of 3 years (1975-1978) and in Tashauz one rise within a period of 5 years (1975-1980) were registered. The analysis of the dynamics of morbidity observed in individual age and social groups showed that these rises, especially those registered in 1976 in Andizhan and in 1977 in Tashauz, were determined by morbidity levels among school children and adults. This is also true for a rise in morbidity rate registered in Tashauz in 1985. In Andizhan the highest morbidity rates among adults were registered in districts insufficiently equipped with modern amenities. Cases of infection registered as hepatitis A (HA) among persons immune to HA at territories with high intensity of the epidemic process of HA at the above-mentioned periods seem to be due to viral hepatitis non A, non B with the fecal-oral mechanism of the transmission of the infective agent.  相似文献   

19.
The complex analysis of materials obtained in different regions and territories of the Far East makes it possible to establish that the natural migration of population affects dysentery morbidity by enhancing the susceptibility of human population to this infection. The internal mechanisms of the influence exerted on morbidity by the natural migration of population is disclosed from the viewpoint of the theory of the self regulation of the epidemic process.  相似文献   

20.
LUCIA LIU SEVERINGHAUS 《Ibis》1996,138(3):460-465
Brown Shrikes Lanius cristatus are both transients and winter residents in Taiwan. Large numbers of birds crowd into the available habitat during the transient period, and the cost of maintaining territories changes greatly, depending on the number of shrikes present. This study examined how wintering Brown Shrikes adapt to the changing level of competition in territory establishment. About 24% of autumn transients arrived before any wintering birds, while 73% of wintering birds arrived during autumn transient time. The frequency of aggression recorded was significantly related to the number of birds seen along the transect line that day. Among ringed birds that returned during transient time, 80% returned directly to their previous territories, but some waited for the departure of transient birds before establishing territories. Territory compression occurred at high population densities. Departure from and arrival at the study area were frequent during the winter, but no birds moved territories within the study area. On average, 25% of ringed wintering shrikes returned to the study site in the subsequent years, while no transients returned. This low site tenacity may be. in part, a result of a high persecution rate along the migration route.  相似文献   

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