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1.
Tests for change-points with epidemic alternatives 总被引:1,自引:0,他引:1
2.
Eviatar Nevo Zeev Gerechter-Amitai Avigdor Beiles Edward M. Golenberg 《Plant Systematics and Evolution》1986,153(1-2):13-30
From 114 accessions of wild emmer wheat from 11 sites in Israel, known for their allozymic variation (Nevo & al. 1982), individual genotypes were tested for resistance to one isolate of stripe rust both in the seedling stage in a growth chamber and in the adult plant stage in the field. The results indicate that resistance to stripe rust in seedlings and adults are significantly correlated (rs = 0.40, p < 0.001). Genetic polymorphisms of resistance to stripe rust vary geographically and are predictable by climatic, as well as allozymic markers. Three variable combinations of rainfall, evaporation, and temperature explain significantly 0.40–0.53 of the spatial variance in disease resistance to stripe rust, suggesting the operation of natural selection. Several allozyme genotypes are significantly associated with disease resistance. We conclude that natural populations of wild emmer wheat in Israel contain large amounts of disease resistance genes. These populations could be effectively screened and then utilized by the phytopathologist for identifying resistant genotypes and producing new resistant cultivars.Patterns of Resistance of Wild Wheat to Pathogens in Israel II. 相似文献
3.
32P-Labelled tRNA was isolated from uninfected and phage phi 149-infected Vibrio cholerae cells. These tRNA preparations were then hybridised with DNA isolated from phage phi 149. Significant hybridisation was observed only with tRNA from phage phi 149-infected cells. This strongly suggests that infection of classical vibrio with phage phi 149 results in the synthesis of phage-specific tRNA molecules. 相似文献
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Following the recovery of naso-pharyngeal cancer patients by trace elements in hair using statistical pattern recognition methods 总被引:1,自引:0,他引:1
This article describes a study where the recovery of nasopharyngeal cancer (NPC) patients was traced by trace elements (TEs)
in hair of these patients. These patients whose concentrations of TEs in hair were studied are volunteers who were divided
into three groups B, C, and D. Group B was made up of volunteers who had just been diagnosed as having NPC, group C and group
D were made up of volunteers who had been diagnosed as having NPC after 3 and 6 mo, respectively, of treatment. For comparison,
a control group, namely group A, which was made up of volunteers from healthy persons was added to this study. By implementation
of statistic pattern recognition methods, it has been found that the concentrations of TEs in hair can remarkably reflect
different recovery phases of NPC patients. 相似文献
9.
Hernández CJ Ortíz T Rosa C Foster K Tyagi M Lugo N Albrecht R Chinapen S 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,146(4):477-481
Mucociliary activity is an important clearance mechanism in the respiratory system of air breathing vertebrates. Substance P (SP) and acetylcholine play a key role in the stimulation of the mucociliary transport in the frog palate. In this study, retrograde neuronal tracing was combined with immunocytochemistry for SP and choline acetyl transferase (ChAT) in the trigeminal ganglion and for neurokinin-1 receptor (NK1R) in the palate of Rana pipiens. The cells of origin of the palatine nerve were identified in the trigeminal ganglion using the retrograde tracer Fluorogold (FG). Optimal labeling of FG cells in the trigeminal ganglion was obtained at 96 h of exposure. Immunoflorescent shows that SP and acetylcholine are co-localized in 92% of the cells labeled with FG in the trigeminal ganglion. NK1 receptors were found in the membrane of epithelial and goblet cells of the palate. Ultrastructural study of the palate showed axonal-like endings with vesicles in connection with epithelial and goblet cells. These results further support the concerted action of both neurotransmitters in the regulation of mucociliary activity in the frog palate. 相似文献
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