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In sarcoidosis, host genetic factors are discussed as contributing to disease susceptibility and course. Since tumor necrosis factor (TNF)-α is a central mediator of granuloma formation and since elevated TNF-α levels are found during active phases of sarcoidosis, genetic polymorphisms correlating with influences on TNF-α levels are of special interest. The complete sequencing of the MHC region and the increase in the number of identified gene polymorphisms in this locus associated with TNF-α production offer the opportunity of detecting new genes associated with sarcoidosis and perhaps of defining disease-associated haplotypes that bear the potential of serving as predictive markers for this disease.  相似文献   
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The energy assimilated by single individuals of aquatic animals throughout their life times and by populations and communities of aquatic animals during the growth season has been studied with due regard for the definitive weight of the single individual and the mean biomass of populations and communities. Energy assimilated throughout life by invertebrates of different systematic positions, definitive size and life duration is about 2.5 times as high as the energetic content of their definitive mass. The energy flow in populations of benthic animals is about 5 times as high as the seasonal average biomass, and in populations of planktonic animals it is 40 times as high. The energy flow in bottom communities is almost 10 times and in planktonic ones 35 times as high as the average seasonal biomass of communities. Specific production (P/B coefficient per 24 h) for communities of bottom animals was 0.013 per 24 h. The average value of the K2 coefficient (net growth efficiency) calculated for an individual's life time is about 0.4 in populations of bottom animals, the K2 for vegetation seasons is 0.26, and for communities it is 0.2 (per vegetation season). Increasing complexity of the biological systems is accompanied by an increase in the specific energy flow and a decline in the efficiency of food energy utilization for production.  相似文献   
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Artificial vesicles, liposomes, were prepared from the total fraction of phospholipids of rat liver mitochondria. Electron microscopy showed that the structure of liposomes depended on cation composition of the medium in which they were formed. Fluorescence of chlorotetracycline increased in the suspension of liposomes loaded with Ca+2 due to the formation of Ca+2-chlorotetracycline-phospholipid membrane complex. Incubation of liposome suspension with phospholipase A in the presence of EDTA resulted in a decrease of chlorotetracycline fluorescence indicating a break of the integrity of liposome membranes and Ca+2 efflux.  相似文献   
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The indigenous Russian Spangled Orloff chicken breed (Large Fowl) was for the first time studied by analyzing polymorphism in loci associated with viral diseases caused by Marek’s disease viruses (MDV), avian leukosis viruses (ALV), and avian influenza viruses. Samples for the analysis were collected at the farms of the All-Russian Poultry Research and Technological Institute (VNITIP), the All-Russian Institute of Farm Animal Genetics and Breeding (VNIIGRZh), and the Moscow Zoo. Assessed populations have a distinction in the frequency and range of allelic variants and as a consequence the frequencies of genotypes LEI0258. The highest level of polymorphism was found in microsatellite loci LEI0258 and Mx1 gene (VNIIGRZh population). The evaluation of polymorphism in genes Mxl (interferon-induced guanosine triphosphatase) and TVB (Tumor Virus В locus, cell receptors) showed, that the Mxl and TVB genotypes associated with resistance to avian influenza viruses and ALV, respectively, were not found in studied populations of Spangled Orloff chicken breed. The most homogeneous group for all studied loci is from the VNITIP population. These data are in good agreement with the results from the study of mtDNA polymorphism in the same samples. The observed polymorphism in nuclear and mitochondrial markers demonstrates that most representative population (about 700 individuals) of Spangled Orloff chicken breed from VNITIP during its long conservation breeding program has remained almost unchanged in the investigated molecular markers and is a source of valuable alleles 357 from microsatellite loci LEI0258 associated with Marek’s disease resistance. The observed frequency of the genotype 357/357 was 48%. The obtained data on the genetic homogeneity of Spangled Orloff chicken breed in all analyzed loci show the need for measures to maintain and increase the number of local groups of Orloffs with the aim of its further preservation.  相似文献   
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