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561.
Summary

We investigated the functional differences in three pairs of S-RNase alleles having similar sequences. It was confirmed using pollination tests that S19 and S28 behaved as different alleles, while S17 and S19 appeared to be the same allele. Our previous new allele designation of S6b in place of S17 and S19, and not S19 and S28, from S-RNase sequence analyses was therefore confirmed. The deduced amino acid sequences of S3 and S10, although showing high similarity (94%), were functionally distinct.  相似文献   
562.
Root rot of lettuce, which is caused by Fusarium oxysporum f. sp. lactucae (FOL), is a critical problem in the production of lettuce. FOL-resistant lettuce genetic resources have been identified and used in breeding programs to produce FOL-resistant cultivars. However, the genetic characteristics of resistance genes have not been studied in depth and, therefore, no DNA markers are presently available for these genes. In this study, we analyzed the RRD2 (resistance for root rot disease race 2) locus, which confers resistance to FOL race 2. Resistance loci were analyzed using two cultivars of crisphead lettuce: VP1013 (resistant) and Patriot (susceptible). The segregation patterns of resistant phenotypes in F2 indicated a single major locus. To define the positions of resistance loci, a linkage map was constructed using amplified fragment length polymorphism and random amplified polymorphic DNA (RAPD) markers. Quantitative trait loci analysis revealed the position of the major resistance locus. A high LOD score was observed for RAPD-marker WF25-42, and this marker showed good correspondence to the phenotype in different cultivars and lines. We successfully developed a sequence characterized amplified region marker from WF25-42.  相似文献   
563.
The present report describes a rare case of spontaneous hemangiosarcoma in a nine-week-old male Sprague-Dawley rat. At necropsy, multiple white nodules of various sizes were observed on and within the enlarged spleen and liver and were histopathologically determined to be composed of spindle- to oval-shaped cells that showed invasive growth without encapsulation and were arranged solidly but partially in whorls or faint alveolar patterns with vascular-like spaces containing small clefts or erythrocytes in the tumor mass. Immunohistochemical analysis revealed that most of the tumor cells were strongly positive for vimentin, von Willebrand factor (vWF) and CD34 but negative for podoplanin. In addition, electron microscopic examination revealed the presence of Weibel-Palade bodies in the cytoplasm of the tumor cells. Based on these findings, this case was diagnosed as a hemangiosarcoma. The splenic masses were larger than the hepatic ones, with tumor cells mainly observed at periportal regions with tumor embolism in the liver, suggesting that primary hemangiosarcoma initially developed in the spleen before metastasizing.  相似文献   
564.
In our previous studies, a clear kinetic isotope effect was observed when a pair of carbohydrate model compounds, methyl ??-d-glucopyranoside (MGP??) and a deuterated MGP?? labeled at the anomeric (methyl ??-d-(1-2H)glucopyranoside) or C-2 position (methyl ??-d-(2-2H)glucopyranoside), was reacted with active oxygen species (AOS) generated by reactions between O2 and a phenolic compound, 2,4,6-trimethylphenol (TMPh), under oxygen delignification conditions. These results indicate that the AOS abstract the anomeric and C-2 hydrogens of MGP??. Contrarily, no clear kinetic isotope effects were observed when AOS were generated by reactions between O2 and another phenolic compound, 4-hydroxy-3-methoxybenzyl alcohol (vanillyl alcohol, Valc), and hence, the abstraction of the anomeric and C-2 hydrogens by the AOS was not confirmed. In this study, a pair of MGP?? and the deuterated MGP?? labeled at all the positions, (2H3)methyl ??-d-(1,2,3,4,5,6,6-2H7)glucopyranoside, was reacted with AOS generated from TMPh or Valc under oxygen delignification conditions to further examine the appearance of a kinetic isotope effect. A clear kinetic isotope effect was observed when either of TMPh or Valc was the origin of AOS, indicating that some AOS abstract at least a hydrogen of MGP?? in either case. The results are further discussed focusing on the type of AOS generated from TMPh and Valc.  相似文献   
565.
This study investigated the densities, average width of annual rings, and partial compression stresses at 5 % strain perpendicular to the grain of air-dried wood specimens, which were continuous in the radial direction from the pith and were obtained from Japanese larch (Larix kaempferi) trees with different diameters at breast height in the same stand, to evaluate the radial variations in partial compression properties perpendicular to the grain. The air-dried densities of the wood increased with the distance from the pith. The average width of annual rings of the wood tended to decrease with increasing distance from the pith and those of medium- and large-diameter trees seemed to increase near the pith. The partial compression stresses at 5 % strain in the tangential loading direction tended to increase with the distance from the pith and with air-dried wood density. However, in the radial loading direction, this tendency was not observed. The partial compression stresses at 5 % strain in the radial loading direction tended to be low in wood with a small average width of annual rings. These results indicate that the factors affecting the radial variations in the partial compression stress at 5 % strain differ depending on the loading directions.  相似文献   
566.
567.
Five novel compounds were isolated from the water extract of Tabebuia avellanedae, and their structures were established by analysis of NMR spectroscopy and mass spectrometry. Compounds 15 at 25 μM showed strong inhibitory activity on the inflammatory cytokine, tumor-necrosis factor-α and interleukin-1β production in cultured human myeloma THP-1 cells co-stimulated with lipopolysaccharide without any significant cytotoxicity, and their anti-allergic and antioxidant activities were evaluated.  相似文献   
568.
569.
Tail DNA genotyping of fetal and neonatal mice from C/EBPbeta heterozygous parents was performed to determine whether the decreased number of surviving C/EBPbeta mutants was caused by prenatal or postnatal death. Eighty-four 3-week-old mice born of heterozygous parents had significantly lower numbers of C/EBPbeta-deficient offspring than the expected Mendelian ratio (29.8%+/+, 65.5%+/-, 4.76%-/-, P<0.05). The genotypes of 72 fetal mice from intercrossed heterozygotes showed approximately the expected 1:2:1 Mendelian ratio (18.1% +/+, 52.8% +/-, 29.2% -/-, P>0.05). No difference in the proportions by sex could be detected in these perinates. This data indicates that C/EBPbeta-deficient mice have unknown lethal problems between the embryonic stage and weaning.  相似文献   
570.
Three antigens were prepared from a type-3 avian strain of Pasteurella multocida, and their chemical and immunologic characteristics were studied. An antigen, designated 2.5S, was extracted with 2.5% NaCl solution and purified by chromatography. Lipopolysaccharide (LPS) was extracted with phenol-water, and a third antigen, designated FS, was extracted in 0.3% formalin solution containing 0.85% NaCl and purified by differential centrifugation. The 2.5S and the FS antigens consisted of 40% protein and 15% carbohydrate, whereas LPS did not contain a substantial amount of protein. A major protein component with a molecular weight of 44,000 was detected in the 2.5S antigen, as well as in the FS antigen. Of the 3 antigens, LPS had the highest activity in mouse lethality and Limulus lysate tests. Antigenic cross-reactions among the 3 antigens were demonstrated by immunodiffusion tests. The 2.5S antigen was indistinguishable from the FS antigen, as both antigens contained the LPS component of approximately 45%. Treatments with various reagents indicated that the 2.5S and FS antigens contained at least 2 antigenic determinants. The first was a heat-stable protein sensitive to protease or phenol-water, and the second was a periodate-sensitive carbohydrate, which was a major antigenic determinant on the LPS antigen.  相似文献   
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