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71.
The outbreak of hemorrhagic fever with renal syndrome (HFRS) in the Republic of Bashkortostan, resulting in 10,057 registered cases of the disease (287 cases per 100,000 of the population), was analyzed. HFRS cases among the population were registered in 52 out of 54 regions of Bashkortostan. 31% of the total number of patients were the inhabitants of rural regions (170 cases per 100,000) and 69% were urban dwellers (295 cases per 100,000), mainly in Ufa (512 cases per 100,000). HFRS morbidity among males was fourfold higher than among females. In 70% of cases persons aged 20-49 years were affected. 5% of the total number of patients were children aged up to 14 years. In 34 cases (0.4%) the severe clinical course of the disease had a fatal outcome. Cases of HFRS were registered from April 1997 till March 1998 with the highest morbidity rate observed during the period of August-December. In most cases (46.8%) both urban and rural dwellers contacted infection during a short-term stay in the forest. As the result of the serological examination of the patients, all HFRS cases were etiologically attributed to hantavirus, serotype Puumala. The main natural reservoir of this virus and the source of human infection in Bashkortostan were bank voles (Clethrionomys glareolus), the domination species among small mammals in this region.  相似文献   
72.
Minin VN  Dorman KS  Fang F  Suchard MA 《Genetics》2007,175(4):1773-1785
We present a Bayesian framework for inferring spatial preferences of recombination from multiple putative recombinant nucleotide sequences. Phylogenetic recombination detection has been an active area of research for the last 15 years. However, only recently attempts to summarize information from several instances of recombination have been made. We propose a hierarchical model that allows for simultaneous inference of recombination breakpoint locations and spatial variation in recombination frequency. The dual multiple change-point model for phylogenetic recombination detection resides at the lowest level of our hierarchy under the umbrella of a common prior on breakpoint locations. The hierarchical prior allows for information about spatial preferences of recombination to be shared among individual data sets. To overcome the sparseness of breakpoint data, dictated by the modest number of available recombinant sequences, we a priori impose a biologically relevant correlation structure on recombination location log odds via a Gaussian Markov random field hyperprior. To examine the capabilities of our model to recover spatial variation in recombination frequency, we simulate recombination from a predefined distribution of breakpoint locations. We then proceed with the analysis of 42 human immunodeficiency virus (HIV) intersubtype gag recombinants and identify a putative recombination hotspot.  相似文献   
73.
Complementarity and cost-efficiency are widely used principles for protected area network design. Despite the wide use and robust theoretical underpinnings, their effects on the performance and patterns of priority areas are rarely studied in detail. Here we compare two approaches for identifying the management priority areas inside the global protected area network: 1) a scoring-based approach, used in recently published analysis and 2) a spatial prioritization method, which accounts for complementarity and area-efficiency. Using the same IUCN species distribution data the complementarity method found an equal-area set of priority areas with double the mean species ranges covered compared to the scoring-based approach. The complementarity set also had 72% more species with full ranges covered, and lacked any coverage only for half of the species compared to the scoring approach. Protected areas in our complementarity-based solution were on average smaller and geographically more scattered. The large difference between the two solutions highlights the need for critical thinking about the selected prioritization method. According to our analysis, accounting for complementarity and area-efficiency can lead to considerable improvements when setting management priorities for the global protected area network.  相似文献   
74.
The role of intermediate filaments (IFs) in eukaryotic cells is still unclear. The disturbance of mitochondria distribution and function, in particular the enhanced production of reactive oxygen species (ROS) and decreased membrane potential, is observed in cells devoid of IFs. The aim of this work was to study the dependence of mitochondria sensitivity to oxidative stress on the presence of vimentin IFs. It was found that mitochondria are less sensitive to ROS in cells containing vimentin than in cells devoid of vimentin. Besides, mitochondrial membrane potential was demonstrated to increase upon regeneration of vimentin IFs in the cells. Substitution of Pro-57 by Arg in N-terminal part of the vimentin molecule abandoned its protective ability and the effect on mitochondrial membrane potential.  相似文献   
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76.
Proteoliposomes containing adenylate cyclase (AC) from rabbit heart ventricles were obtained using a novel reconstitution procedure from solubilized state. The enzyme preparation can be stimulated by 5'guanylylimidodiphosphate (GppNHp) and NaF, but not by isoproterenol. Hormonal responsiveness of AC is restored by either isoproterenol trapped by the proteoliposomes during the reconstitution or pretreatment of proteoliposomes with alamethicin. GTP in the presence of alamethicin decreases the affinity of beta-adrenoceptors to the agonist, thus confirming that the properties of reconstituted AC system do not differ from the native one. It is demonstrated that the degree of AC activation by isoproterenol depends strongly on the beta-adrenoceptors content in the proteoliposomes, which in turn can be changed artificially in the process of reconstitution. The described reconstitution technique might be a useful tool for investigating the role of component stoichiometry in the functioning of hormone-regulated AC-system.  相似文献   
77.
Understanding factors that affect the persistence of charismatic megafauna in human‐dominated landscapes is crucial to inform conservation decision‐making and reduce human‐wildlife conflict. We assessed the effect of environmental and anthropogenic factors at different landscape and management scales in predicting the distribution of African elephant (Loxodonta africana) within the Greater Mapungubwe Transfrontier Conservation Area in Southern Africa. We combined aerial distribution counts over a 12‐yr period with 14 variables, representing food availability, landscape, and anthropogenic effects, into generalized linear models. Generalized linear models were run for the broader landscape, as well as three separate management units within the broader landscape, namely ecotourism, trophy hunting, and a combination of hunting and ecotourism. Human activities within different management units forced elephant to trade‐off between disturbance avoidance, and good food and water availability. In addition, the important predictors of elephant distribution within each of the management units differed from the predictors at the broader landscape. Overall, our results suggest that at the fine scale, elephant are constraint by factors that may be masked at the broader landscape scale. We suggest that accounting for anthropogenic disturbance is important in determining the distribution of large, wide‐ranging, mammal species in increasingly human‐dominated landscapes, and that modeling needs to be done at the spatial scales at which conservation decisions are made.  相似文献   
78.
It is common knowledge that zebrafish, Danio rerio, oocytes in their follicular envelope that have reached definitive size undergo in vitro maturation in 90% Leibovitz’s medium, pH 9.0, when treated with 17α, 20β-dihydroxyprogesterone and acquire developmental competence but do not ovulate (Seki et al., 2008). We have demonstrated that zebrafish oocytes that have undergone maturation under the indicated conditions ovulate when treated with prostaglandin F (5 μg/mL) and/or 20% carp ovarial fluid and are capable of development towards the actively feeding larvae upon fertilization (the maximum follow-up period).  相似文献   
79.
By means of a complex of cost-effective, rapid, and, whenever possible, computerized screening procedures, a systematic two-week study period of the functional states of subjects in a small group of healthy adults was performed. The daily variations of 125 parameters and periodic changes in 51 parameters of somatic and mental health were investigated at increasing doses of an adaptive drug. In the initial state of the subjects, various deviations of the somatic parameters from the normal level were found, presumably of a nutritional origin. The adaptive drug was found to normalize the changed parameters of somatic health within a week due to a strain in the regulatory systems and a decline in the functional reserves of adaptation. At the end of the examination, excessive doses of the adaptive drug returned the majority of the somatic parameters to the initial levels. At the same time, the work capacity of the subjects decreased and the strain on the autonomic nervous system and the level of stress increased. Discomfort and fatigue developed, which restricted the abilities of the examined subjects to choose behavioral tactics.  相似文献   
80.
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