Fleas of the Moiynkum Desert and their epizootic significance

The species composition of fleas in the Moiynkum Desert (Chu-Talas interfluve) and indices of their domination on different hosts was established on the basis of long-term observations (1973–2000). The most significant and prolonged changes in the population density of mass flea species (Xenopsylla gerbilli minax and Coptopsylla lamellifer, parasites of the great gerbil) occur in association with changes of the population density of rodents. Changes in the population density of rodents are usually observed year after similar changes in the population density of hosts. The leading role in the transmission of the plague vector belongs to the flea X. gerbilli minax.     

Ecology of the geohelminths of Karakul sheep in the Kyzyl Kum

Data on the ecology of geohelminths and epizootiology of main geohelminthiases of Karakul sheep under conditions of desert-pasture biocoenoses of the Kyzyl Kum in the Bukhara and Navoi Provinces of the Uzbek SSR are given. 23 species of geohelminths belonging to 14 genera and 8 families are reported from this zone. Age and seasonal dynamics of the infection rate of Karakul sheep with geohelminths are established. Survival of eggs and larvae of some widely distributed geohelminths in central Kyzyl Kum is determined. On the basis of results of investigations recommendations on the control of main helminthiases of Karakul sheep in Bukhara and Navoi Provinces are worked out.     

A new species of the grass fly (Diptera,Chloropidae), Incertella tschernovi sp. n., from the Kyzyl Kum Desert

A new grass fly species belonging to the subfamily Oscinellinae, Incertella tschernovi sp. n., is described from the Kyzyl Kum Desert, Uzbekistan. The new species is closely related to I. brevicosta Nartshuk, 1975, shares short costal vein of the wing and in the vein M sharply bent toward the anterior wing margin.     

A small-mammal study in the northeastern Kara Kum for leptospirosis infectivity]

Search for natural foci of leptospirosis was carried out in 1987-1989 in humid biotopes of Tashauz Province, Turkmenistan. Such potential carriers of leptospirosis as house mice (Mus musculus) and tamarisk gerbils (Meriones tamariscinus) are widely spread in this area, and the size of their population can amount to great numbers. The sharpest fluctuations in the population size are characteristic of house mice inhabiting the shores of water collecting ponds and lakes in the regions of minimally used pastures. A moderate number of house mice was registered in spring and autumn at the area of irrigated agriculture. Only here and only in autumn a faint epizootic manifestation of the natural focus of L. grippotyphosa infection in house mice was registered for the first time in Turkmenistan. The titers in mouse blood sera, determined in the microagglutination test and the Leptospira lysis test, were 1:20 to 1:200. According to the data on the humidity and pH of the soil in the vicinity of irrigated fields, spring and summer months may be regarded as the most favorable period for the survival of leptospires in the environment. The probability of the aggravation of the epizootic situation seems to increase when irrigated fields adjoin pastures of are temporarily used as grazing ground for cattle.     

Tumor plasminogen activators and their clinical significance]

By means of a radio-immunological method the amount of plasminogen activators released by tumours was determined. The concentrations of tumour plasminogen activators was considerably higher in the venous blood of ovarial tumours than in the peripheral blood. In the uterine fluid the uterus cavity the concentration of plasminogen activator was increased in cases with neoplastic endometrium compared to those with normal endometrium.     

Molecular characterization of epizootic hemorrhagic disease virus serotype 1 associated with a 1999 epizootic in white-tailed deer in the eastern United States

During the autumn of 1999 (mid-August-late September), an outbreak of hemorrhagic disease in white-tailed deer (Odocoileus virginianus) caused by epizootic hemorrhagic disease virus serotype 1 (EHDV-1) occurred along the east coast of the United States from Georgia to New Jersey. An EHDV-1 epizootic of such magnitude had not been described in this region since 1975. To determine the genetic relatedness among the 1999 viruses, as well as among additional EHDV-1 isolates from the eastern and western United States, portions of the S10 and L2 gene segments were sequenced and compared utilizing phylogenetic analyses. Nearly all of the 1999 eastern isolates were identical in nucleotide sequence at one or both loci. Additionally, confirmed cases of EHDV-1 in white-tailed deer occurred in a south (Georgia)-to-north (New Jersey/Virginia) progression over a short period of approximately six weeks. Taken together, these results indicate that this outbreak resulted from the spread of a single viral strain. The phylograms derived from analysis of the entire sample set displayed eastern and western region-specific clusterings (topotypes), as well as an eastern versus western difference in branch lengths, which may reflect the influence of epizootic versus enzootic transmission patterns on viral genetic diversity.     

Free radicals and their biological significance: present and future]

Free radicals are usually active species which have unpair electron (S) in molecules or Atomic groups. Of the free radicals, O2- and .OH could easily be produced in mammalian cells, by oxidation and reduction cycle catalyzed by fravoproteins and by iron + H2O2 reaction, respectively. Other free radicals would also be produced in mammalian cell, such as amino acid radicals, semiquinone radicals and flavine radicals etc. In general, free radicals cause cell injury though membrane lipid peroxidation and DNA strand cleavage and some other mechanisms.     

The structural characteristics of the phrenic nucleus in the cat and their functional significance]

The structural elements of phrenic nucleus have been compared under the horseradish peroxidase introduction into the phrenic muscle and using a silver staining method. All the neurons of nucleus have been proposed to be motoneurons. The characteristic features of phrenic nucleus organisation are created by the groups of motoneurons and their dendritic bundles. Each nucleus contains about 800 motoneurons. Their sizes have been determined in three planes. Some functional characteristics of phrenic nucleus on the basis of its structural architecture are under discussion.     

Rodents and their predators in the eastern Bay of Islands

Abstract

Traps were set for rodents and mustelids on five islands (Motukiekie, Moturua, Okahu, Urupukapuka, and Waewaetorea) in the eastern Bay of Islands in March 1984. Kiore (Rattus exulans) were caught on Moturua Island and Norway rats (R. norvegicus) on all five islands, but no mustelids were caught or seen. Kiore on Moturua Island were very scarce compared with other northern offshore islands, perhaps because of competition from Norway rats and the presence of stoats and cats. Kiore were breeding and young matured in the season of their birth. Norway rats were scarce and found mainly near the shoreline on four of the islands. On Waewaetorea Island they were plentiful and widespread despite the possible presence of stoats. About a third of the mature females were visibly pregnant. Average litter size was 6.9 embryos, and 44% of the parous females had borne two or three litters. Females first ovulated at 180 ± 5 g weight and 356 ± 5 mm total length on average. Males first produced sperm at 189 ± 7 g weight and 364 ± 4 mm total length. Most rats matured before reaching a tooth-wear age index of 5.     

异构前列腺素及其意义

异构前列腺素是花生四烯酸经氧自由基催化的代谢产物,不依赖于环氧化酶,在体内外脂质过氧化试验中均有大量的ｉｓｏ－ＰＧｓ生成,抗氧化剂有抑制作用。ｉｓｏ－ＰＧｓ可做为脂质过氧化的一个新的特异的指标用于临床、病理与药理研究。     

Ticks on lemmings in the eastern Taimyr]

13 taxons of mites associated with lemmings and their nests are reported from East Taimyr. Mass. species are as follows: Parsitus (Eugamasus) sp., L. lemmi, Hg. ambulans, H. isabellinus. Irregular spread of mites in the lemmings'nests favours the creation of conditions sutiable for the circulation of agents of transmissible infections. A more regular distribution of these mites on the animals points to the mixing of the mites population that effects the dissemination of agents. The finding of females with effs (Hg. ambulans, H. isabellinus) on the animals and their simultaneous absence in the nests of the latter show that in the northern parts of the distribution areas of these species their life patterns have an epizootic character.     

Kyzyl ash disposal area as a source of unfavorable effect on the environment

The work studied the physic-technological characteristics of ash-and-slag waste of Kyzyl heat station. It revealed the chemical, elementary, and mineral compositions of the obtained products of fractioning. The content of hazardous substances in the fine fractions of ash and in ground water served as a basis for the conclusion that the dust-forming fraction of the ash-and-slag waste exerts the primary influence over the environment as a result of aerial transmission.