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Studies of arboviruses started in Yugoslavia in 1953 following the isolation of TBE virus which caused a severe epidemic that year. Until now the following viruses have been proven to circulate in the country: tick-borne encephalitis (TBE), Crimean-Congo hemorrhagic fever (CCHF), Bhanja (BHA), sandfly fever (SF), Tahyna (TAH), Calovo (CVO), West Nile (WN), dengue (DEN), Jug Bogdanovac (JB), and Hantaviruses. TBE virus is endemic in the north-west part of the country, causing also epidemics in cyclical intervals. Its typical clinical picture is aseptic meningitis, but severe cases with paralysis have also been described. The bite of ticks is confirmed in about 80% of cases. CCF caused a small epidemic with ten clinical cases in Macedonia in 1976. Bhanja virus was isolated on the Dalmatian island of Brac in 1977, the antibody rate there, determined by the HI method, being about 31%. The first human disease in the world was caused by the Yugoslav Bhanja virus strain. Sandfly fever is still active in the country. The Naples type is prevailing and has proved hazardous for newcomers. Hantaviruses have been studied since 1980. They caused severe epidemics (1967, 1980, 1989) and sporadic cases all over the country. Three different strains are in circulation. Further studies are needed for the rest of the above mentioned viruses to learn more about their significance in human pathology.  相似文献   

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Geographical distribution of African freshwater fishes   总被引:5,自引:0,他引:5  
Geographical distribution of African freshwater fishes is discussed with emphasis on the effects of major continental features, hydrographic history, and Pleistocene climatic fluctuations. Differences in the modes of dispersal and biological interactions among various categories of fishes, ecological as well as phyletic, have also had marked effects on distribution.
The African continent can be divided into ten ichthyofaunal provinces. The geography of these provinces and composition of their fish faunas is briefly described. The paper concludes with a consideration of the faunistic relationships of African lakes with endemic fishes.  相似文献   

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The distribution of C 3 types in Norway   总被引:1,自引:0,他引:1  
P Teisberg 《Human heredity》1971,21(2):154-161
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BackgroundBurkholderia pseudomallei is a Gram-negative bacterium found in soil and water in many tropical countries. It causes melioidosis, a potentially fatal infection first described in 1911 in Myanmar. Melioidosis is a common cause of sepsis and death in South and South-east Asia, but it is rarely diagnosed in Myanmar. We conducted a nationwide soil study to identify areas where B. pseudomallei is present.Methodology/Principal findingsWe collected soil samples from 387 locations in all 15 states and regions of Myanmar between September 2017 and June 2019. At each site, three samples were taken at each of three different depths (30, 60 and 90 cm) and were cultured for B. pseudomallei separately, along with a pooled sample from each site (i.e. 10 cultures per site). We used a negative binomial regression model to assess associations between isolation of B. pseudomallei and environmental factors (season, soil depth, soil type, land use and climate zones). B. pseudomallei was isolated in 7 of 15 states and regions. Of the 387 sites, 31 (8%) had one or more positive samples and of the 3,870 samples cultured, 103 (2.7%) tested positive for B. pseudomallei. B. pseudomallei was isolated more frequently during the monsoon season [RR-2.28 (95% CI: 0.70–7.38)] and less in the hot dry season [RR-0.70 (95% CI: 0.19–2.56)] compared to the cool dry season, and in the tropical monsoon climate zone [RR-2.26; 95% CI (0.21–6.21)] compared to the tropical dry winter climate zone. However, these associations were not statistically significant. B. pseudomallei was detected at all three depths and from various soil types (clay, silt and sand). Isolation was higher in agricultural land (2.2%), pasture land (8.5%) and disused land (5.8%) than in residential land (0.4%), but these differences were also not significant.Conclusion/SignificanceThis study confirms a widespread distribution of B. pseudomallei in Myanmar. Clinical studies should follow to obtain a better picture of the burden of melioidosis in Myanmar.  相似文献   

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中国蜱类地理分布及区系分析   总被引:3,自引:0,他引:3  
利用聚类分析的方法,对中国蜱类的分布和地理区系进行了分析.结果表明:中国蜱类呈点状和带状分布;蜱类在中国分布的聚类分析结果与中国的动物地理区划基本一致,但华北区及甘肃、安徽、河南、云南与中国大陆动物区系差异较大.因此,有必要对这些地区作进一步调查.  相似文献   

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Aim To describe and explain geographical patterns of false absence and false presence prediction errors that occur when describing current plant species ranges with species distribution models. Location Europe. Methods We calibrated species distribution models (generalized linear models) using a set of climatic variables and gridded distribution data for 1065 vascular plant species from the Atlas Florae Europaeae. We used randomly selected subsets for each species with a constant prevalence of 0.5, modelled the distribution 1000 times, calculated weighted averages of the model parameters and used these to predict the current distribution in Europe. Using a threshold of 0.5, we derived presence/absence maps. Comparing observed and modelled species distribution, we calculated the false absence rates, i.e. species wrongly modelled as absent, and the false presence rates, i.e. species wrongly modelled as present, on a 50 × 50 km grid. Subsequently, we related both error rates to species range properties, land use and topographic variability within grid cells by means of simultaneous autoregressive models to correct for spatial autocorrelation. Results Grid‐cell‐specific error rates were not evenly distributed across Europe. The mean false absence rate was 0.16 ± 0.12 (standard deviation) and the mean false presence rate was 0.22 ± 0.13. False absence rates were highest in central Spain, the Alps and parts of south‐eastern Europe, while false presence rates were highest in northern Spain, France, Italy and south‐eastern Europe. False absence rates were high when range edges of species accumulated within a grid cell and when the intensity of human land use was high. False presence rates were positively associated with relative occurrence area and accumulation of range edges. Main conclusions Predictions for various species are not only accompanied by species‐specific but also by grid‐cell‐specific errors. The latter are associated with characteristics of the grid cells but also with range characteristics of occurring species. Uncertainties of predictive species distribution models are not equally distributed in space, and we would recommend accompanying maps of predicted distributions with a graphical representation of predictive performance.  相似文献   

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Phagocata vivida (Ijima et Kaburaki, 1916) is common in cold-water habitats in mountainous and hilly regions in Japan; in Northern Japan it occurs in lowland areas. Comparative studies of the material from South Korea and Primorskiy in Northeast Siberia, Russia, show that Ph. vivida is distributed widely in these geographic areas. Phagocata miyadii Okugawa, 1939, reported from North Korea and Northeastern China is a synonym of Ph vivida. Geographical distribution of this species in the Japanese Islands now becomes very clear. Judging by its geographical and vertical distributions, the species probably is a preglacial faunal element that entered Japan by the northern route to Old Honshû Island along the coast of the Old Sea of Japan.  相似文献   

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Seiji Tokumasu 《Mycoscience》2001,42(6):575-589
The geographical distribution of a saprotrophic hyphomycete,Sporidesmium goidanichii was studied in pine forests of Japan. Using the data of 282 fungal communitles of pine leaf litter collected over a wide range of climatic conditions, the relationships among two indexes of distribution of the species (constancy and abundance) and three climatic variables were analyzed by the multiple regression analysis. The results demonstrated that the mean annual air temperature and the mean annual range (the difference in monthly mean air temperatures between the coldest and warmest months at the study sites) were necessary variables for the prediction of the values of indexes ofS. goidanichii in pine forests of Japan, while the mean annual precipitation was an unimportant factor. The distribution patterns of the fungus along the gradients of two temperature variables were analyzed graphically. The fungus has an optimal climatic area with high values of indexes where is restricted to the center of the warm temperate regions of the main islands. The relationship between the life strategy of the fungus and its temperature-dependent distribution pattern in Japan was also discussed. Contributions to Sugadaira Montane Research Center No. 179.  相似文献   

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The complete mitochondrial (mt) genome of the neuropathogenic bird schistosome Trichobilharzia regenti was fully sequenced in order to develop molecular markers for future diagnostic, molecular ecological, population, and phylogenetic studies. The genome was 14,838 bp in length, with a 68.4% AT bias in protein coding regions. A repeat element (3 x 184 bp) between trnV and trnW distinguished a single short noncoding region. As 9 of 14 genera of schistosomes parasitize birds, future characterization of their mt genomes is desirable for species-specific and strain- or population-specific diagnostic markers; this concerns not only the nasal representatives, e.g., T. regenti characterized in this study, but also numerous species within the predominant group of visceral (blood dwelling) bird schistosomes.  相似文献   

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The distribution of eleven dictyostelid cellular slime molds found in Norway was studied. They were divided into four groups according to their dominance. In decreasing order the groups were: (1) two varieties of Dictyostelium mucoroides , (2) D. aureostipes and Polysphondylium violaceum , (3) D. fasciculatum, D. minutum, P. pallidum and Dictyostelium sp. 1, and (4) Dictyostelium sp. 2 and 3 and Acytostelium lep–tosomum. Differences in distribution related to altitudes and latitudes, climates and dominant tree species were observed for some species.  相似文献   

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This study was planned to determine the number of origins of the mutation underlying Huntington's disease (HD) in Sweden. Haplotypes were constructed for 23 different HD families, using six different polymorphisms [(CCG) n , GT70, 674, BS1, E2 and 4.2], including two within the gene. In addition, extensive genealogical investigations were performed, and the geographical origin of the haplotypes was studied. Ten different haplotypes were observed suggesting multiple origins for the HD mutation in Sweden. Analysis of the two polymorphic markers within the HD gene (the CCG repeat and GT70) indicates that there are at least three origins for the HD mutation in Sweden. One of these haplotypes (7/A) accounts for 89% of the families, suggesting that the majority of the Swedish HD families are related through a single HD mutation of ancient origin. Furthermore, three of the families that were previously considered to be unrelated could be traced to a common ancestor in the 15th century, a finding that is consistent with this hypothesis.  相似文献   

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鹅掌楸在中国的自然分布及其特点   总被引:29,自引:3,他引:29  
鹅掌楸(Liriodendronchinense(Hemsl.)Sarg.)星散分布于长江流域以南海拔450~1800m阔叶林中。依其自然地理区域,鹅掌楸在我国西部,从北由大巴山,经武陵山、大娄山,伸向云贵高原东部,形成一条东北.西南走向分布带,在东部和中南部,有5个各自以中、低山为中心,被平原相间隔的“岛”状分布。较大种群多分布在我国西部。与北美鹅掌楸(L.tulipiferaL.)在北美洲的分布相比,鹅掌楸为星散间断分布,天然更新不良,在自然群落中多为偶见种。中国东部和西部鹅掌楸在形态上存在较明显的差别,西部种群在花被片颜色,叶片裂片变化及同工酶等方面表现出与北美鹅掌楸有更多的相似特性。因而推论,现存鹅掌楸属的这两个对应种,在地史上是通过欧洲及大西洋陆桥建立联系的  相似文献   

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