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排序方式: 共有442条查询结果,搜索用时 15 毫秒
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Genetic and phylogenetic analysis of glycoprotein of rabies virus isolated from several species in Brazil 总被引:10,自引:0,他引:10
Sato G Itou T Shoji Y Miura Y Mikami T Ito M Kurane I Samara SI Carvalho AA Nociti DP Ito FH Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(7):747-753
Genetic and phylogenetic analyses of the region containing the glycoprotein (G) gene, which is related to pathogenicity and antigenicity, and the G-L intergenic region were carried out in 14 Brazilian rabies virus isolates. The isolates were classified as dog-related rabies virus (DRRV) or vampire bat-related rabies virus (VRRV), by nucleoprotein (N) analysis. The nucleotide and amino acid (AA) homologies of the area containing the G protein gene and G-L intergenic region were generally lower than those of the ectodomain. In both regions, nucleotide and deduced AA homologies were lower among VRRVs than among DRRVs. There were AA differences between DRRV and VRRV at 3 antigenic sites and epitopes (IIa, WB+ and III), suggesting that DRRV and VRRV can be distinguished by differences of antigenicity. In a comparison of phylogenetic trees between the ectodomain and the area containing the G protein gene and G-L intergenic region, the branching patterns of the chiropteran and carnivoran rabies virus groups differed, whereas there were clear similarities in patterns within the DRRV and VRRV groups. Additionally, the VRRV isolates were more closely related to chiropteran strains isolated from Latin America than to Brazilian DRRV. These results indicate that Brazilian rabies virus isolates can be classified as DRRV or VRRV by analysis of the G gene and the G-L intergenic region, as well as by N gene analysis. 相似文献
84.
Ortlepp T Ariando Mielke O Verwijs CJ Foo KF Rogalla H Uhlmann FH Hilgenkamp H 《Science (New York, N.Y.)》2006,312(5779):1495-1497
The d-wave pairing symmetry in high-critical temperature superconductors makes it possible to realize superconducting rings with built-in pi phase shifts. Such rings have a twofold degenerate ground state that is characterized by the spontaneous generation of fractional magnetic flux quanta with either up or down polarity. We have incorporated pi phase-biased superconducting rings in a logic circuit, a flip-flop, in which the fractional flux polarity is controllably toggled by applying single flux quantum pulses at the input channel. The integration of p rings into conventional rapid single flux quantum logic as natural two-state devices should alleviate the need for bias current lines, improve device symmetry, and enhance the operation margins. 相似文献
85.
After the diagnosis sarcoptic mange in four alpaca's (Lama pacos) we have tried to control this infection. Despite three treatments with doramectin, three with ivermectin, four with amitraz and two with diazinon we were unable to get the animals free of Sarcoptes mites and their condition deteriorated. One animal died six month after the first treatment. The three remaining animals were euthanized one month thereafter. 相似文献
86.
Colletotrichum lindemuthianum, causal agent of anthracnose in the common bean, has wide genetic variability. Differential bean cultivars and morphological and physiological characteristics were used to analyze 74 isolates of C. lindemuthianum collected in two counties in the state of Minas Gerais, Brazil. Six different races were found, with a predominance of race 65 at both locations. Isolates were classified according to their sensitivities to the fungicide thiophanate-methyl, normally used in the control of common bean anthracnose. In all, ≈10% of isolates were resistant to the fungicide in vitro. Characteristics such as indexes of mycelia growth rate, colony diameter, sporulation capacity, and percentage of germination demonstrated the high genetic variability of C. lindemuthianum. We also observed variation in conidial cytology. The conidia of most isolates showed septa formation after germination, in contrast to septa absence, previously reported in the literature. Sexual and asexual reproduction were evaluated for mechanisms that may contribute in the generation of variability in C. lindemuthianum. Conidial anastomosis tubes were commonly found, indicating that asexual reproduction can help increase variability in this species. Information from this study confirmed high variability in C. lindemuthianum and will guide future studies in basic knowledge and applied technologies. 相似文献
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Geng YY Yang FH Xing XM Gao XH 《Journal of animal physiology and animal nutrition》2012,96(4):610-617
The objective of this study was to determine whether nutrient digestibility and production performance of growing-furring blue foxes (Alopex lagopus) are affected by different dietary fat levels. Sixty-four young animals were randomly assigned to four groups (A, B, C, D) provided with diets containing approximately 12%, 26%, 40%, 54% fat in the dry matter respectively. When dietary fat level was increased, the apparent digestibility of main nutrients except for crude carbohydrates, and gross energy were improved (p < 0.0001). The amount of nitrogen excreted was reduced and the biological value of protein was enhanced (p < 0.0001). Over the experimental phase, the efficiency of metabolizable energy (ME) used for gain in group B (26% fat content) was higher than that in other groups. When diets with 12-26% fat content were fed, there was an increasing tendency in skin size. But it had negative effects on skin size and fur quality when the amount of fat content was over 40%. In conclusion, the experiment showed that dietary fat could significantly improve some nutrient utilization and significantly reduce feed/gain ratio as a main energy source. The most preferable fur quality and efficiency of ME used for gain were obtained when diet contained 26% fat level in growing-furring period. 相似文献
89.
Soy protein, mixed with gluten and starch, was extruded into fibrous meat analogues under high-moisture and high-temperature conditions. The protein solubility of samples collected at different extruder zones and extrudates made with different moistures was determined by 11 extraction solutions consisting of 6 selective reagents and their combinations: phosphate salts, urea, DTT, thiourea, Triton X-100, and CHAPS. Protein solubility by most extractants showed decreasing patterns as the material passed through the extruder, but the solution containing all 6 reagents, known as isoelectric focus (IEF) buffer, solubilized the highest levels and equal amounts of proteins in all samples, indicating that there are no other covalent bonds involved besides disulfide bonds. With regard to relative importance between disulfide bonds and non-covalent interactions, different conclusions could be made from protein solubility patterns, depending on the type of extracting systems and a baseline used for comparison. The observation points out pitfalls and limitation of current protein solubility methodology and explains why controversy exists in the literature. Using the IEF buffer system with omission of one or more selective reagents is considered to be the right methodology to conduct protein solubility study and thus recommended. Results obtained with this system indicate that disulfide bonding plays a more important role than non-covalent bonds in not only holding the rigid structure of extrudates but also forming fibrous texture. The sharpest decrease in protein solubility occurred when the mix passed through the intermediate section of the extruder barrel, indicating formation of new disulfide bonds during the stage of dramatic increase in both temperature and moisture. After this stage, although the physical form of the product might undergo change and fiber formation might occur as it passed through the cooling die, the chemical nature of the product did not change significantly. 相似文献
90.