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21.
A female congenic rat produced by repeated backcrossing of Nihon rats, a model for hereditary renal cell carcinoma, to Brown Norway rats was necropsied at 24 months of age. At necropsy, a white mass about 1 centimeter in size was observed in the thoracic cavity, and the mass partly adhered to the esophagus and the diaphragm. Histologically, the mass was clearly circumscribed by connective tissue, and consisted of neoplastic cuboidal epithelial cells that showed cystic tubular proliferation. Some islands of well-differentiated hepatocytes and some vessels were observed in the mass. Immunohistochemically, the tumor cells were strongly positive for cytokeratin and partly positive for vimentin but were negative for mesothelin and Von Willebrand Factor. The positive rate for Ki-67 was 2.4%. Based on these histological and immunohistochemical evidences, we diagnosed this tumor as a cystic cholangioma that might have arisen from the ectopic hepatic tissue in the thoracic cavity.  相似文献   
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The chemoattractant activity of a new chemotactic factor, 'Gasserokine' produced by Lactobacillus gasseri JCM1131T, has been proposed as a novel immunological function of probiotic lactic acid bacteria. The focus of the present study was to understand the mechanism of the chemotaxis induced by Gasserokine, using activation of an adhesion molecule, Mac-1 (CD11b/CD18) on macrophages. The macrophage chemotaxis to Gasserokine was abolished by preincubation of macrophages with the anti-Mac-1 mAb. Gasserokine induced rapid serine phosphorylation of CD18 molecules within 1 min of stimulation, but the effect was short-lived. Substantial tyrosine phosphorylation was observed in CD18-associated protein of macrophages stimulated by Gasserokine. The tyrosine phosphorylation was confirmed in macrophages stimulated with Gasserokine and also serine/threonine phosphorylation was detected on CD18 molecules by laser microscopy using a double immunostaining method. These results suggest that selective activation of intracellular signaling cascades, such as the mitogen-activated protein kinase pathway, are related to the macrophage chemotaxis induced by Gasserokine.  相似文献   
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Single nucleotide polymorphism (SNP) arrays are widely used for genetic and genomic analyses in cattle breeding; thus, data derived from SNP arrays have accumulated on a large scale nationwide. Commercial SNP arrays contain a considerable number of unassigned SNPs on the chromosome/position on the genome; these SNPs are excluded in subsequent analyses. Notably, the position‐unassigned SNPs, or “buried SNPs” include some of the markers associated with genetic disease. In this study, we identified the position of buried SNPs using the Basic Local Alignment Search Tool against the surrounding sequences and characterized the relationship between SNPs and genetic diseases in Online Mendelian Inheritance in Animals based on the genomic position. We determined the position of 285 buried SNPs on the genome and surveyed the genotype and allele frequencies of these SNPs in 5,955 individual Japanese Black cattle. Eleven SNPs associated with genetic disease, which contained five buried SNPs, were found in the population with the risk allele frequency ranging from 0.00008396 to 0.46. These results indicate that buried SNPs in the bovine SNP array can be utilized to identify associations with genetic disorders from large scale accumulated SNP genotype data in Japanese Black cattle.  相似文献   
25.
A rapid, easy method has been developed for isolating and quantifying 2-methyl-3-furanthiol (2M3F) in wines. Until now, it was not possible to quantify this highly odoriferous compound, with a smell reminiscent of cooked meat, in wine. The original aspect of this method is the specific release of volatile thiols using a cysteamine solution applied in reverse flow to sample percolation on the basis of a p-hydroxymercuribenzoate (pHMB)-volatile thiol conjugate formed by the direct addition of pHMB to 50 mL of wine. Purification of volatile thiols in wines is much faster and easier than our previous method. This method may also be used to assay 2-furanmethanethiol in wine. This thiol's strong aroma of roasted coffee has been shown to contribute to the "roast coffee" aroma of certain wines. Assaying 2M3F by this method showed that it was present in the wines analyzed (red and white Bordeaux, Loire Valley Sauvignon blanc, white Burgundy, and Champagne) at concentrations up to 100 ng/L, i.e., significantly above the olfactory perception threshold for this compound in model dilute alcohol solution.  相似文献   
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Summary The release of extremely early maturing varieties has made it possible to cultivate rice in Hokkaido (NL45-42°) in Japan, the northern limit region of paddy rice cultivation. Until then, rice cultivation in this region has been impracticable due to the climate condition, especially short summer and long-day more than 15 hours during summer. Experiment results confirmed that the success of rice cultivation in this area depends on raising photoperiod insensitivity varieties with short basic vegetative growth period. Moreover, in this study, the genetic factors controlling the photoperiod insensitivity of Hokkaido varieties were analyzed by using 8 kinds of tester lines for three loci, E1, E2, and E3, controlling photoperiod sensitivity. It was found out that all the varieties examined carry el, a photoperiod insensitivity allele of E1 locus, but as for the other loci, E2 and E3, the existence of plural alleles were recognized. We have already clarified that almost all the japonica-type varieties grown in Japan (except Hokkaido) and Taiwan carry E1 bringing about strong photoperiod sensitivity. Accordingly, it can be concluded that el is the gene essential to Hokkaido varieties: the interchange of E1 with e1 enabled rice cultivation under long-day condition.  相似文献   
28.
Recent genetic analyses on heading-time of rice indicated that almost all the well-adapted varieties in the temperate zone carry a strong photoperiod-sensitivity gene E1, a dominant allele of E1 locus. In order to identify the chromosome on which E1 is located, a trisomic analysis was made using two primary trisomic series originating from the japonica varieties, Nipponbare and Kinmaze, respectively. The Nipponbare and Kinmaze series were crossed with heading-time tester lines, EG0 and EG3, respectively, both of which did not carry the E1. The F2 populations for chromosome 1, 2, and 3 could not be analyzed due to lack of seed. All the other F2 populations showed distinct segregation into early-type and late-type plants caused by the E1 locus segregation, which suggested that the trisomic analysis for E1 locus could be efficiently made. Both disomic and trisomic groups in the F2 population from the cross of the trisomic line for chromosome 7 × EG0 showed a segregation ratio significantly different at the 1% level from a ratio of 1 [e1e1; early]: 3 [E1e1, E1E1; late]. This suggested that E1 was located on chromosome 7. Subsequently, the linkage analysis was made using three morphological marker genes on chromosome 7. It was recognized that E1 was linked to rfs (rolled fine strip gene) and slg (slender glume gene) with recombination values of 16.3 ± 5.88 and 9.1 ± 4.72%, respectively. From these results, it can be concluded that E1 is most likely to be located on chromosome 7. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
29.
Endotoxin causes gastrointestinal motility disorder. Aim of this study is to clarify inhibitory mechanisms of lipopolysaccharide (LPS) on smooth muscle contraction in rat ileum. Ileal tissues were isolated from control rat or from LPS-induced peritonitis model rat. Treatment with LPS inhibited carbachol (CCh)-mediated contraction in a time-dependent manner. Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes were also upregulated, but iNOS expression was preceded by a rising of COX-2. All subtypes of prostaglandin E2 (PGE2) receptors (EP1-EP4) were expressed in ileum, and PGE2 and selective EP2 or EP4 agonist inhibited CCh-mediated contraction. Selective iNOS inhibitor did not reverse LPS-induced inhibition of contraction by CCh at 1 and 2 hr, but reduced the inhibitory action at 4 hr after the LPS treatment. COX-2 inhibitor reversed the inhibitory action by LPS in all exposure time. Finally, in ileal tissues isolated from peritonitis model rat, iNOS expression was upregulated only at 4 hr after LPS administration, resulting in enhanced inhibitory action of LPS against CCh-induced contraction. In conclusion, LPS induces COX-2 to produce PGE2, which initially activates EP2 and/or EP4 on smooth muscle cells to inhibit the contractility in early phase of LPS exposure. Moreover, in late phase of LPS treatment, iNOS is expressed to produce NO, which in turn inhibited the contraction by CCh. The inhibitory cascade is similar in the ileum isolated from peritonitis model rat, indicating time-dependent changes of inhibitory action by LPS on intestinal motility in peritonitis.  相似文献   
30.
Benzenemethanethiol, a volatile thiol with a strong empyreumatic aroma reminiscent of smoke, has been identified in boxwood (Buxus sempervirens L.) as well as in red and white Vitis vinifera L. wines. The perception threshold in a model hydroalcoholic solution is approximately 0.3 ng/L. All of the wines analyzed for this study contained this compound in concentrations of several dozen nanograms per liter. The Chardonnay wines had 30-40 ng/L. Sensory discrimination between a wine containing 7 ng/L benzenemethanethiol and the same wine with an additional 4 ng/L is very significant; the difference in smell is described as "empyreumatic". This compound can therefore significantly contribute to the aroma of certain wines (Sauvignon Blanc, Semillon, Chardonnay, etc.) containing concentrations as high as 30-100 times higher than their perception threshold.  相似文献   
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