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121.
Nonsteroidal anti-inflammatory drug (NSAID)-activated gene (NAG-1), a divergent member of the transforming growth factor beta superfamily, was previously identified as a gene induced by several anti-tumorigenic compounds, including NSAIDs and peroxisome proliferator-activated receptor gamma (PPARgamma) ligands in humans. In this study, canine NAG-1 was characterised from a canine genomic database. Gene induction by some NSAIDs and PPARgamma ligands was demonstrated in canine osteosarcoma cell lines. Phylogenetic analysis indicates that canine NAG-1 is more homologous with the corresponding mouse and rat genes than with human NAG-1. Expression of canine NAG-1 was increased by treatment with piroxicam and SC-560 (NSAIDs) and the PPARgamma ligand rosiglitazone. This study demonstrates that canine NAG-1 is up-regulated by some anti-tumorigenic compounds in osteosarcoma cell lines and may provide an important target of chemotherapy in canine cancer.  相似文献   
122.
Although basic fibroblast growth factor (bFGF) is an essential factor supporting the maintenance of porcine embryonic stem (ES) cell self‐renewal and pluripotency, its high cost has limited previous studies, and the development of a low‐cost culture system is required. For these systems, in vivo blastocysts were progressively cultured under various conditions consisting of different culture mediums and/or different feeder cell numbers at a low concentration of bFGF. As the results, the sequential culture of in vivo‐derived porcine blastocysts on 5.0 × 105 mouse embryonic fibroblast (MEF) feeder cells in alpha minimum essential medium‐based medium for primary culture, on 2.5 × 105 MEF feeder cells in Mixture medium for the 1st subpassage, and on 2.5 × 105 MEF feeder cells in DMEM/Ham's F10‐based medium for the post‐2nd subpassage could support the establishment and maintenance of porcine ES‐like cells at the low concentration of bFGF. The established porcine ES‐like cells showed ES cell‐specific characteristics such as self‐renewal and pluripotency. We confirmed that porcine ES‐like cells could be generated from in vivo‐derived porcine blastocysts at a low concentration of bFGF.  相似文献   
123.
Aloe species, which have been used as medicinal plants, belong to the Asphodelaceae family consisting of 530 species. In this study, genetic diversity and phylogenetic relationships among 40 Aloe species including a putative interspecies hybrid were analyzed using PCR band profiles from eight chloroplast intergenic space markers and nucleotide sequence diversity in the psbK–psbI intergenic region. A phylogenetic tree based on psbK–psbI sequences supported the revised classification of the genus Aloe as polyphyletic with several species be re-allocated into three genera Kumara, Aloidendron, and Aloiampelos. Further, the origin of the putative interspecies Aloe hybrid was characterized through molecular cytogenetics. Fluorescence and genomic insitu hybridization illustrated that the hybrid has a bimodal karyotype with a chromosome complement of 2n = 14, of which complementary halves were derived from two parental species, A. vera and A. arborescens. These findings revealed that the hybrid species was allodiploid. The phylogenetic analysis showed that A. arborescens was the maternal genome donor of the hybrid, as both have identical chloroplast genome sequences. We thus conclude that the allodiploid hybrid should be called A. arborescens × A.vera.  相似文献   
124.
The utility of ferroelectric materials stems from the ability to nucleate and move polarized domains using an electric field. To understand the mechanisms of polarization switching, structural characterization at the nanoscale is required. We used aberration-corrected transmission electron microscopy to follow the kinetics and dynamics of ferroelectric switching at millisecond temporal and subangstrom spatial resolution in an epitaxial bilayer of an antiferromagnetic ferroelectric (BiFeO(3)) on a ferromagnetic electrode (La(0.7)Sr(0.3)MnO(3)). We observed localized nucleation events at the electrode interface, domain wall pinning on point defects, and the formation of ferroelectric domains localized to the ferroelectric and ferromagnetic interface. These results show how defects and interfaces impede full ferroelectric switching of a thin film.  相似文献   
125.
The antioxidant properties of the Pacific chub mackerel (Scomber japonicus) muscle protein hydrolysates prepared by enzymatic hydrolysis were investigated. After enzyme hydrolysis at 50°C for 60 min, more than 80% of the S. japonicus muscle protein was hydrolyzed. The highest 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity (71.69%) occurred in whole muscle protein hydrolysates treated at 50°C for 30 min with Protamex, and the highest 2,2?-azino-bis(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) radical-scavenging activity (95.39%) was observed in white muscle protein hydrolysates treated at 50°C for 30 min with Neutrase. The highest superoxide dismutase (SOD)-like activity (32.84%) was recorded in white muscle protein hydrolysates treated at 50°C for 120 min with Protamex. Changes in the molecular weight distribution of S. japonicus muscle proteins after enzymatic hydrolysis were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A robust and a convenient enzyme hydrolysis technique for obtaining S. japonicus muscle protein hydrolysates with useful biological activities, within a short time (<2 h) is proposed.  相似文献   
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