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Bovine articular cartilage was photo-oxidized and cultured with native articular bovine cartilage and synovial membrane to study the interaction between these tissues mimicking the physiological situation in the joint. The photo-oxidation was applied as a pretreatment of cartilage for future use in cartilage resurfacing procedures in joints. Properties of the transplant were assessed by testing the production of local mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2), and neutral metalloproteinase activities under normal conditions and after stimulation with various stimulants representative of inflammatory changes in pathophysiological conditions. Unlike normal cartilage photo-oxidized cartilage did not release significant amounts of NO and PGE2 and showed less gelatinolytic and caseinolytic activity compared to native bovine articular cartilage. Enzyme activity of the combined cultures was at a level intermediate between that of photo-oxidized cartilage and native cartilage cultures alone. In contrast to normal cartilage, living chondrocytes were not visible in photo-oxidized cartilage using live/dead staining. These results indicate, that the photo-oxidized cartilage may have a beneficial effect on adjacent native host cartilage and therefore be a suitable transplant for use in in vivo experiments.  相似文献   
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Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares.  相似文献   
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Pompe's disease: detection of heterozygotes by lymphocyte stimulation   总被引:4,自引:0,他引:4  
A technique has been developed for the detection of inborn errors by multiple enzyme analysis of lymphocytes stimulated by phytohemagglutinin. Its practicality has been demonstrated in Pompe's disease in which there is a deficiency of acid alpha-1,4-glucosidase (E.C.3.2.1.20).  相似文献   
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Comparison of the deduced amino acid sequences of the genes (S10) encoding the NS3 protein of 137 strains of bluetongue virus (BTV) from Africa, the Americas, Asia, Australia and the Mediterranean Basin showed limited variation. Common to all NS3 sequences were potential glycosylation sites at amino acid residues 63 and 150 and a cysteine at residue 137, whereas a cysteine at residue 181 was not conserved. The PPXY and PS/TAP late-domain motifs were conserved in all but three of the viruses. Phylogenetic analyses of these same sequences yielded two principal clades that grouped the viruses irrespective of their serotype or year of isolation (1900-2003). All viruses from Asia and Australia were grouped in one clade, whereas those from the other regions were present in both clades. Each clade segregated into distinct subclades that included viruses from single or multiple regions, and the S10 genes of some field viruses were identical to those of live-attenuated BTV vaccines. There was no evidence of positive selection on the S10 gene as assessed by reconstruction of ancestral codon states on the phylogeny, rather the functional constraints of the NS3 protein are expressed through substantial negative (purifying) selection.  相似文献   
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Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene.  相似文献   
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Transgenic technology holds considerable promise to advance understanding in biomedical and agricultural systems with some believing that one day transgenic animals may directly contribute to farming and breeding practice. Nevertheless, applications in livestock have been restricted in part by the inefficiency of the technology. The recent development of lentivirus vectors for transgene delivery may overcome some of this limitation. This presentation describes these vectors, their advantages and limitations.  相似文献   
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