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21.
The open reading frame of the S3 segment encoding the sigma2 protein of four turkey reovirus field isolates was analyzed for sequence heterogeneity. The turkey reoviruses we present here have a 97% amino acid identity to turkey NC 98. The S3 nucleotide and amino acid sequence similarity was < or =61% and 78%-80%, respectively, when compared to the chicken reovirus isolates. Comparison of amino acid sequences from chickens and turkeys with that of a duck isolate revealed a 53% and 55% similarity, respectively. Phylogenetic analyses, based on both nucleotide and amino acid sequence, resulted in three major groups among the avian reoviruses; these groups were clearly separated by species. The results of this study provide further evidence, based on the deduced sigma2 sequence, that turkey reoviruses form a distinct, separate group relative to chicken and duck isolates. In addition, as a result of the limited sequence identity with their avian counterparts, turkey reoviruses could potentially be considered a separate virus species within subgroup 2 of the Orthoreovirus genus. 相似文献
22.
Bruchpilot promotes active zone assembly, Ca2+ channel clustering, and vesicle release 总被引:1,自引:0,他引:1
Kittel RJ Wichmann C Rasse TM Fouquet W Schmidt M Schmid A Wagh DA Pawlu C Kellner RR Willig KI Hell SW Buchner E Heckmann M Sigrist SJ 《Science (New York, N.Y.)》2006,312(5776):1051-1054
The molecular organization of presynaptic active zones during calcium influx-triggered neurotransmitter release is the focus of intense investigation. The Drosophila coiled-coil domain protein Bruchpilot (BRP) was observed in donut-shaped structures centered at active zones of neuromuscular synapses by using subdiffraction resolution STED (stimulated emission depletion) fluorescence microscopy. At brp mutant active zones, electron-dense projections (T-bars) were entirely lost, Ca2+ channels were reduced in density, evoked vesicle release was depressed, and short-term plasticity was altered. BRP-like proteins seem to establish proximity between Ca2+ channels and vesicles to allow efficient transmitter release and patterned synaptic plasticity. 相似文献
23.
Omer-Elfaroug Sid-Ahmed Ahmed Sanhouri Badr-Eldin Elwaseela Imad Fadllalah Galal-Eldin Elazhari Mohammed Erich Möstl 《Tropical animal health and production》2013,45(6):1453-1458
The aim of this study was to determine whether glucocorticoid production could be monitored non-invasively in dromedary camels by measuring faecal cortisol metabolites (FCMs). Five Sudanese dromedaries, two males and three females, were injected with a synthetic adrenocorticotropic hormone (ACTH) analogue. Blood samples were collected pre- and post-ACTH injection. Faeces were sampled after spontaneous defecation for five consecutive days (2 days before and 3 days after ACTH injection). Baseline plasma cortisol values ranged from 0.6 to 10.8 ng/ml in males and from 1.1 to 16.6 ng/ml in females, while peak values after ACTH injection were 10.9–41.9 in males and 10–42.2 ng/ml in females. Peak blood cortisol values were reached between 1.5 and 2.0 h after ACTH injection. The concentration of FCMs increased after ACTH injection in the faeces of both sexes, although steroid levels peaked earlier in males [24 h; (286.7–2,559.7 ng/g faeces)] than in females [36–48 h; (1,182.6–5,169.1 ng/g faeces)], reflecting increases of 3.1–8.3- and 4.3–8-fold above baseline levels. To detect chromatographic patterns of immunoreactive FCMs, faecal samples with high FCM concentrations from both sexes were pooled and subjected to reverse phase high performance liquid chromatography (RP-HPLC). RP-HPLC analysis revealed sex differences in the polarity of FCMs, with females showing more polar FCMs than males. We concluded that stimulation of adrenocortical activity by ACTH injection resulted in a measurable increase in blood cortisol that was reliably paralleled by increases in FCM levels. Thus, measurement of FCMs is a powerful tool for monitoring the adrenocortical responses of dromedaries to stressors in field conditions. 相似文献
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Erich Seemüller Eckard Moll Bernd Schneider 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):217-223
Progenies of 39 open-pollinated genotypes belonging to 26 Pyrus taxa were examined for pear decline resistance and pomological traits when used as rootstocks. Following graft inoculation
and observation over 18 years, considerable differences in pear decline resistance between and within the progenies were observed.
Not affected or little affected and moderately to severely affected trees were observed in all progenies. However, great quantitative
differences among them were observed. In the progenies of about one third of the pollinated trees most of the individuals
showed a high level of resistance to grafted trees. Significantly different from this group was another third of the progenies
that mostly showed high susceptibility in grafted trees. Between these two groups there were progenies that statistically
neither differed from the resistant nor from the susceptible group. These progenies were defined as moderately resistant.
Significant differences in resistance were also observed between progenies of genotypes of the same species that originated
from different locations. These data indicate segregation of the resistance trait and show that seedling progenies are unsuitable
as rootstocks in commercial pear growing. Instead, careful selection of suitable genotypes for propagation is required. Great
differences between and within the progenies examined were also observed in vigour and yield efficiency. 相似文献
30.
Diplomlandwirt Erich Kuhn 《Journal of pest science》1926,2(9):126-127
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