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Characteristics of a new Salmonella serotype, subgenus IV, are reported. Culture 5534-68 was recovered from the intestinal tract of Anolis biporcatus, an arboreal lizard found in deep forest tracts in Panama Province, Republic of Panama. The antigenic composition of this new serotype was found to be 50(1, 2, 3):z(4), z(24):-.  相似文献   

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The pellicle was isolated from the cell homogenate obtained on sonication of Euglena gracilis z grown aerobically under illumination and purified by a combination of differential and sucrose density gradient centrifugations. The purity and homogeneity of the pellicle fragments were determined by an electron microscopic method and biochemical analysis of the components. The protein, lipid, and sugar contents of the purified pellicle were 68.7, 17.9, and 13.5%, respectively. The equilibrium density of pellicle fragments was 1.21 g/cm3. SDS-polyacrylamide gel electrophoresis revealed that the pellicle contained 50 mol% of nonpolar amino acids. The constituents of the lipid and sugar were very different from those of the cell membrane of other organisms.  相似文献   

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Hit selection is the ultimate goal in many high-throughput screens. Various analytic methods are available for this purpose. Some commonly used ones are z score, z* score, strictly standardized mean difference (SSMD), SSMD*, and t statistic. It is critical to know how to use them correctly because the misusage of them can readily produce misleading results. Here, the author presents basic concepts, elaborates their commonality and difference, describes some common misusage that people should avoid, and uses simulated simple examples to illustrate how to use them correctly.  相似文献   

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D C Rao 《Human heredity》1979,29(6):334-336
When correlations are estimated by maximum likelihood method from the same sample, Fisher's z transformations of the correlations (as well as the sample correlations themselves) are shown to be asymptotically distributed as multivariate normal with appropriate mean and dispersion matrix.  相似文献   

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The central complex is a brain specific structure involved in multimodal information processing and in coordinating motor behaviour. It possesses a highly organized neuroarchitecture, which is remarkably conserved across insect species. A prominent feature of this neuroarchitecture is the stereotypic projection of axons from clusters of neurons in the pars intercerebralis to the central body via the so-called w, x, y and z tracts. Despite extensive analyses of this neuroarchitecture in adults, little is known about its ontogeny in any insect. In this paper we use the expression pattern of the segment polarity gene engrailed to identify those neuroblasts belonging to the protocerebrum of the early embryonic brain of the grasshopper Schistocerca gregaria. We present a new map for this brain region in which the 95 protocerebral neuroblasts in each hemisphere are organized into seven rows, as they are in the neuromeres of the ventral nerve cord. We then identify a subset of four of these neuroblasts as being the progenitor cells for four clusters of neurons, some of whose axons we show project via discrete tracts (w, x, y, z) into the central complex. These tracts begin to form prior to 39% of embryogenesis. We show further, that the cells from one of these clusters (the Z cluster) are organized according to age, and direct axons topologically according to age into the appropriate z tract. This pattern is repeated in each of the other three clusters, thus establishing a clonally based modular system of fibre tracts consistent with the model proposed for this brain region in the adult.  相似文献   

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A new Salmonella serovar S.III b 58:z10:z53:Rz50 was isolated from the water samples of Ashida river, Fukuyama city, Japan. Its antigenic structure is described.  相似文献   

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Agrin isoforms with different bioactivities are synthesized by the nerve and the muscle. Neural agrin containing an 8-amino acid insert (z8) introduced by alternative splicing is the active form that induces synaptic differentiation at the neuromuscular junction. In addition to alternative splicing, extracellular calcium is also required for the activity of neural agrin. To understand better how the activity of agrin is regulated by alternative splicing, we have applied alanine substitution mutagenesis to the z8 insert and the calcium binding site in the minimally functional AgG3z8 fragment. Single alanine substitutions in the 4th through the 7th amino acid of the z8 splice insert significantly reduced the function of agrin, in terms of acetylcholine receptor clustering activity and the affinity for binding to the muscle surface. Mutation of the asparagine at the 4th position drastically reduces bioactivity such that it is equivalent to that of muscle form AgG3z0. These reduced activity mutants also show reduced magnitudes of the calcium-induced CD spectrum change from that observed in AgG3z8 fragments, indicating that cross-talk between calcium and the z8 insert is critical for the normal activity of agrin. However, removal of Ca2+ binding via mutation of both aspartic acids in the calcium binding site did not totally eliminate the activity of AgG3z8. These results suggest a model wherein the z8 insert is a Ca2+-responsive allosteric element that is essential in forming an active conformation in neuronal agrin.  相似文献   

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Ohne ZusammenfassungVorgetragen auf der Tagung der Internationalen Pflanzenzüchter-Vereinigung am 11. Juni 1931 in Berlin.  相似文献   

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Novel antioxidative phenylpropanoid-substituted tocopherol derivatives, prunusols A and B, were isolated from the leaf wax of Prunus grayana Maxim., and their structures were fully characterized by spectroscopic and synthetic methods. Prunusols A and B were found to be the conjugates of γ-tocopherol and p-coumaric acid, which are diastereoisomers of each other. They showed almost the same antioxidative activity as α-tocopherol in a water/alcohol system measured by thiocyanate and TBA methods.  相似文献   

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In contrast to reported fact, the air-grown cells of Euglena gracilis z were found to excrete glycolate into the surrounding medium, when placed in an atmosphere of 100% O2 under illumination at 20000 lux at the same rate of the 5% CO2-grown cells, but with a lag phase of about 30 min. The lag was eliminated by lowering intracellular CO2 concentration in the air-grown cells.This paper is the eighth in a series on the metabolism of glycolate in Euglena gracilis.  相似文献   

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