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41.
The present study involved the isolation and characterization of canine tumor endothelial cells (TECs) from 2 malignancies. TECs were isolated using magnetic cell sorting following FITC labeling with UEA1 lectin, and they were characterized by measuring genetic and histopathological endothelial markers. Isolated TECs exhibited a cobblestone-like morphology and expressed both vascular endothelial growth factor receptor 2 (VEGFR2) and Von Willebrand factor (vWF). Further, both TECs and tumor cells derived from a seminoma exhibited increased C-X-C chemokine receptor type 7 (CXCR7) expression. However, CXCR7 expression was not detected in TECs and tumor cells derived from a hepatocellular carcinoma. Understanding TEC specific traits may be important in the development of more efficacious anti-angiogenic therapies that do not induce adverse effects.  相似文献   
42.
Skin lesions possibly caused by Papillomavirus infections in two four-toed hedgehogs are described. In case 1, there was a papillary mass on the right hind limb. Histologically, the mass was consistent with a viral papilloma. In the other case, multifocal papillary masses with erosions and ulcers were found throughout the body, mainly on the extremities. Histology showed continuative lesions composed of acanthosis, Bowenoid in situ carcinoma, and squamous cell carcinoma, with abrupt transitions between the lesions. In both cases, keratinocytes in the granular layer infrequently had features of koilocytes and intranuclear inclusion bodies, and immunohistochemical staining was positive for anti-human papillomavirus antibody. To the best of the authors’ knowledge, this is the first pathological documentation of possibly papillomavirus-associated skin lesions in four-toed hedgehogs.  相似文献   
43.
The mechanism of paper sizing in fatty acid soap size-alum systems was studied by structural analyses of the size components in handsheets prepared with13C-labeled fatty acid soap size. Patterns of sizing performance and aluminum content of the handsheets were similar to those for the rosin soap size-alum sizing systems, although the patterns of calcium content were different. Solid-state13C-nuclear magnetic resonance analysis of the handsheets revealed that fatty acid calcium salt was the predominant size component in the handsheets prepared using tap water. This calcium salt is formed from the fatty acid soap size (fatty acid potassium salt) by ion exchange with calcium ion in pulp suspensions and retained on pulp fibers through aluminum compounds originating from alum added. On the other hand, when deionized water was used, free fatty acid was the major component in the handsheets. Fatty acid aluminum salt was present as a minor component in the handsheets prepared in both tap water and deionized water systems. Therefore, all size components (i.e., fatty acid calcium salt, free fatty acid, fatty acid aluminum salt) seem to contribute to the appearance of sizing features.This research was presented in part at the 64th Pulp and Paper Research Conference of Japan TAPPI, Tokyo, June 1997  相似文献   
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To detect the predominant lactobacilli in the intestinal flora of healthy thoroughbreds, we isolated lactobacilli from the feces of nine thoroughbreds (five males and four females; 0–15-year-old). The isolated lactobacilli comprise 17 species (37 strains), and they were classified into five groups: Lactobacillus salivarius (6 species), L. reuteri (6 species), Lactobacillus delbrueckii (3 species), L. buchneri (1 species) and L. vitulinus (1 species). On the basis of 16S rRNA gene sequences, we identified 3 other phylogenetic relatives belonging to the genus Lactobacillus . These results suggest that the intestinal flora of thoroughbreds may comprise many species of the genus Lactobacillus . Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analyses of the 340-bp fragments of the 16S rRNA genes from the same nine fecal samples showed that L. hayakitensis , L. equigenerosi and L. equi are contained in all the samples, suggesting that these species are predominant lactobacilli in the intestinal flora of thoroughbreds.  相似文献   
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In avian species, blood immunoglobulin (Ig) Y, the equivalent to mammalian IgG, is selectively incorporated into ovarian follicles, but other classes, IgA and IgM, are much less abundant in the follicles. Several mammalian Igs, including IgG and IgA, are also incorporated into ovarian follicles when administered to birds. To clarify the Ig structure required for incorporation into ovarian follicles, Ig uptakes were determined after the intravenous injection of chicken and human Igs. Three chicken Igs (cIgY, cIgA and cIgM) and two human IgAs (monomeric hIgA and polymeric hIgA) were labeled with digoxigenin, and their uptakes into quail (Coturnix japonica) egg yolks were determined by ELISA and SDS-PAGE. The uptake of cIgY was the highest among the three cIgs (22% of injected cIgY was recovered from egg yolks). Chicken IgA was efficiently incorporated into egg yolk when it formed a monomeric state. Pentameric IgM was untransportable into egg yolk. We also found that the uptake of monomeric hIgA was much more efficient than that of polymeric hIgA. These results suggest that the retention of the monomeric form contributes to the efficient transport of Igs into ovarian follicles. On the other hand, Ig uptakes among monomeric Igs nevertheless differed; for example, a time-course analysis showed that the rate of monomeric cIgY uptake was approximately eight times faster than that of monomeric hIgA. The injection of cIgY fragments Fc, Fab and F(ab')(2) resulted in the largest uptake of Fc fragment, with the same level as that of cIgY. These results suggest the presence of a selective IgY transport system that recognizes its Fc region in avian ovarian follicles.  相似文献   
48.
Insulin/insulin-like growth factor (IGF)-like signaling plays important roles in the aging processes of various animals. However, little is known about this signaling in rotifers, which have been used as a model animal in aging studies. Here we report that the aqueous extracts of the rotifer Brachionus plicatilis show activity similar to that of insulin/IGFs. Rotifers were cultured under four different feeding regimens (fed, starved for about ten days, or re-fed for 30 and 120 min after starvation), and then their aqueous extracts were added to culture media of rat L6 myoblasts. Treatment with these extracts increased the phosphorylation levels of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and two Akt substrates of approximately 48 and 60 kDa, and these phosphorylations were diminished when cells were preincubated with specific inhibitors of their upstream kinases (MAPK/ERK kinase and phosphoinositide 3-kinase, respectively). Furthermore, the extracts from fed rotifers provoked higher phosphorylation levels of MAPK/ERK and Akt substrates than the extract from starved rotifers, suggesting that the production of substance(s) with insulin/IGF-like activity is stimulated upon feeding in the rotifer.  相似文献   
49.
Insulin‐like growth factor‐1 (IGF1) plays an important role in muscle development in chickens. In this study, an F2 chicken population of 362 individuals, obtained from an intercross between high breast muscle yield line males and low breast muscle yield (LB) line females, was constructed for investigating the associations between IGF1 gene and breast muscle yields. The IGF1 sequence was investigated in the grandparents. There were no differences in the exon sequences. However, sequence analysis of the IGF1 promoter revealed a known single nucleotide polymorphism (g.570C > A) in LB line grandparents. PCR – restriction fragment length polymorphism was used for screening the F2 population, which was evaluated for body weight (BW), carcass weight (CW), breast muscle weight (BMW), and breast fillet weight (BFW). Significant associations with the polymorphism were detected for BMW, BFW, BMW% and BFW%, although there were no associations between the polymorphism and BW or CW. The allelic effect on BMW, BFW, BMW% and BFW% acted in additive and dominance modes. We confirmed that the g.570C > A polymorphism is significantly associated with breast muscle yields in the F2 population. Therefore, this polymorphism in the IGF1 gene may help improve breast muscle yields by marker‐assisted selection.  相似文献   
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