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To clarify the contribution of autologous transplantation of mesenchymal stromal cells (MSCs), an atelocollagen gel containing or not containing fluorescently-labeled canine MSCs was transplanted into an osteochondral defect which did not repair spontaneously and the histological repair of the defect was compared. Although an early repair of the cartilage was not observed in either defect, the reproduction of subchondral bone was remarkable in the MSCs-implanted defect. Moreover, in 2 weeks after operation, the implanted MSCs were located in the deeper regions of the defect, suggesting the differentiation of osteoblasts. There was a possibility that the movement of the implanted MSCs was due to an increase in intra-articular pressure from postoperative inflammation.  相似文献   
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Ferret polymorphonuclear cells (PMNs) and peripheral blood mononuclear cells (PBMCs) were separated from whole blood by density gradient centrifugation. Using a 50% Percoll solution (density=1.066), PMNs and PBMCs were successfully isolated after centrifugation; the purities of the PMNs and PBMCs were 94.2% and 95.6%, respectively. To evaluate the function of isolated ferret PMNs, we measured the superoxide generation with a MCLA-dependent chemiluminescence assay. The isolated ferret PMNs responded to phorbol 12-myristate 13-acetate (PMA) with kinetics similar to that of human PMNs. The ferret PMNs did not respond to N-formyl-Met-Leu-Phe (fMLF), unlike human PMNs, which rapidly responded. Thus, authors established a method for the rapid separation of highly purified populations of functional PMNs from the whole blood of ferrets.  相似文献   
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The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.  相似文献   
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张敏 《中国沼气》2009,27(5):18-20
前期研究表明梭菌属的新株JC3(Clostridiumsp.Strain JC3)是嗜热产甲烷污泥中的主要纤维素降解菌。本项目采用分子生物学技术定量研究了菌株JC3在高温厌氧消化过程中的作用。在含三个小室(室1,室2,室3)的厌氧折流板反应器(9.5 L)中进行纤维素降解实验,试验温度设为55℃。当负荷为2.5 kg COD.m-3d-1,HRT为2天时,80%以上的COD进料都转化为甲烷。采用专门针对菌株JC3的特异性荧光针来研究折流式反应器中污泥样品。结果表明JC3细胞对DAPI染色细胞的比例从低于0.5%(最低检测极限)增加到9.4%(室1),13.1%(室2)和21.6%(室3)。这表明由荧光原位杂交技术确定的菌株JC3细胞数与滞留污泥的纤维素降解产甲烷活性密切相关。设计了一个针对菌株JC3纤维素酶基因(纤维二糖水解酶A cbh A)的特异探针,并应用到处理固体废弃物如咖啡渣、废纸、垃圾和纤维素等消化污泥中,采用定量PCR技术发现菌株JC3细胞数与高温消化器中污泥的纤维素降解能力密切相关。因此,在高温厌氧消化过程中,菌株JC3对厌氧水解纤维素是非常重要的。  相似文献   
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This study was performed to obtain information on the occurrence of multiple paternities in three species of viviparous Japanese surfperch using allelic markers of microsatellite DNA loci. Direct evidence for multiple fertilizations was established by reconstructing paternal genotypes from the progeny of gravid females. Multiple paternities were ascertained in five of 10 broods of Ditrema temmincki and in three of nine broods of Neoditrema ransonneti, but not in Ditrema viride. The number of patrilines detected in the progeny of D. temmincki and N. ransonneti females were two or three, respectively, as determined by the GERUD v2.0 algorithm for reconstructing parental genotypes from half-sib progeny arrays.  相似文献   
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SUMMARY: The aim of this study was to investigate the cause of green liver in red sea bream fed substitute protein diets. Red sea bream Pagrus major was given either of the following diets for 28 weeks: (1) control diet (50% fish meal), (2) low level fish meal diet (15% fish meal), and (3) non-fish meal diet (0% fish meal). The green liver was observed in all groups tested, but the incidence was much higher in the experimental diet groups. The feeding of substitute protein diets reduced plasma triglyceride and cholesterol levels. However, there was no significant difference in plasma hepatic enzyme activities and plasma bile salts concentration among the treatments. Fish fed the substitute protein diets showed low hepatic taurine levels with an appearance of a biliverdin in the liver. Moreover, the proportion of ditaurobilirubin to total biliary bile pigments was significantly lower in fish fed the substitute protein diets. These data indicate that feeding of substitute protein diets did not induce any cholestatic hepatobiliary obstructions and that the low hepatic taurine level was one of the probable factors responsible for the occurrence of green liver in red sea bream fed substitute protein diets.  相似文献   
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We succeeded to establish cell lines from endemic fish species Honmoroko Gnathopogon caerulescens, which inhabits Lake Biwa, the third oldest lake in the world. Two cell lines designated as RMT1 and RMO1 were established from testis and ovary of G. caerulescens, respectively. These cell lines were initially cultured in Leibovitz’s L-15 medium supplemented with fetal bovine serum (FBS), fish embryo extract, epidermal growth factor, and basic fibroblast growth factor. Further addition of forskolin and β-mercaptoethanol was required to establish and maintain these cell lines for more than 60 passages. RMT1 and RMO1 cells showed fibroblast- and epithelial-like morphology, respectively. From immunocytochemical staining and gene expression patterns, RMT1 cells showed a characteristic of testicular Sertoli cells and RMO1 cells did that of ovarian theca cells. Both RMT1 and RMO1 cells multiplied well in the medium supplemented with 10 % FBS at 28 °C and their minimum population doubling times were 24.4 and 28.8 h, respectively. At the 45th passage, most of the RMT1 and RMO1 cells had a hyperploid set of chromosomes (67.3 and 96.1 %, respectively). Cells with normal diploid chromosome set were not observed. RMT1 cells were transfected with an enhanced green fluorescent protein (EGFP) expression vector and human elongation factor 1 α promoter worked efficiently to express EGFP. In addition, EGFP-expressing cell lines were also established, suggesting that the cell lines could be utilized as an in vitro monitor system (biosensor) for the evaluation of endocrine disruptors which might affect gonadal function.  相似文献   
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ABSTRACT:   A total of 110 adult individuals from four ommastrephid (family Ommastrephidae) squid species ( Ommastrephes bartramii, Sthenoteuthis oualaniensis, Eucleoteuthis luminosa, and Hyaloteuthis pelagica ) were used to obtain diagnostic DNA markers for species identification. Restriction fragment length polymorphism (RFLP) analysis of a partial segment (855 bp) of the mitochondrial DNA cytochrome oxidase I (COI) gene amplified by polymerase chain reaction (PCR) revealed that the restriction profiles of two endonucleases ( Alu  I and Tsp 509 I) were diagnostic for species identification. The restriction assay partially supplemented with nucleotide sequence analysis successfully assigned 69 damaged and morphologically equivocal ommastrephid paralarvae collected in northern Hawaiian waters, identifying 60 O. bartramii , eight S. oualaniensis , and one E. luminosa . The family Ommastrephidae appears to be monophyletic. Although the phylogenetic relationships among genera were not resolved well due to apparent homoplasy and large genetic divergence between species, COI sequence data without transitions provided support for subfamily level relationships.  相似文献   
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