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Recombinant Bone Morphogenetic Proteins: Novel Substances for Enhancing Bone Healing 总被引:1,自引:0,他引:1
CARL A. KIRKER-HEAD MA Vel MB MRCVS Diplomate ACVS Diplomate ECVS 《Veterinary surgery : VS》1995,24(5):408-419
Bone morphogenetic proteins (BMPs) are differentiative factors whose principal function is to induce transformation of undifferentiated mesenchymal cells into chondroblasts and osteoblasts in a dose-dependent manner. Bone morphogenetic proteins have been isolated postnatally in mammals from bone matrix, periosteal cells, mesenchymal cells of marrow stroma, tooth anlagen, and cells of osteosarcoma and chondrosarcoma. Distribution in additional embryonic tissues implies a broader organogenic function. Bone morphogenetic proteins are the only differentiative factors able to singularly induce de novo bone formation in vitro and in vivo. Recombinant DNA technology allows their production in large and highly purified quantities. The BMPs' osteoinductive ability has been shown with a variety of carriers including collagens and polymers at heterotopic and orthotopic sites in a wide range of species. They are presently being readied for clinical use as alternatives to bone grafts. Other potential applications include use as pulp capping agents, promoters of implant osteointegration and soft tissue reunion with bone, treatments for nonadaptive bone disease, and implants for use with mitotically expanded skeletal stem cell populations. Errors in the genetic coding of BMPs may manifest as clinical disease entities. 相似文献
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Malm O Guimarães JRD Castro MB Bastos WR Viana JP Branches FJP Silveira EG Pfeiffer WC 《Water, air, and soil pollution》1997,97(1-2):45-51
Informal economy of gold mining has contaminated some important river basins in Amazon. Follow-up studies on critical compartments showed some areas with high Hg levels in fish as well as in human hair samples. Average Hg in piscivorous fish in the Madeira river itself was 846 ppb (N=284) with a maximum of 3921 ppb. Mercury in fish from non polluted areas in this basin shows high variability, even for single species. A seasonal variation in Hg content was observed, with higher values at the end of the dry season. In the upper Tapajós basin comparable values were found for fish but with a definite decreasing trend downstream. Average value for piscivorous fish in the whole Tapajós basin is 482 ppb (N=122) with a maximum value of 3770 ppb. Hair Hg was higher in fishing villages in the Tapajós (average: 17 ppm; with N=432 and maximum value of 176 ppm) than in the Madeira (average: 9 ppm; N=169; maximum 71 ppm), and data from some areas of the Tapajós suggest a decrease with time. Mercury was much higher in urine of goldshop workers in Santarém (low Tapajós) than in Alta Floresta (high Tapajbs) and show a decreasing trend in both cases, probably related to the significant decline in gold mining activities during the study period (1986–1994). 相似文献
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TRIXACARUS CAVIAE IN GUINEA PIGS 总被引:1,自引:0,他引:1
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The situation in Thoroughbred breeding in relation to cytogenetics is considered and it is indicated where screening of horses will be useful in practice. The techniques involved are explained and karyotypes are illustrated. The present state of knowledge in horse cytogenetics is reviewed. The types of abnormality are described in relation to phenotype. Future promise is discussed in relation to the human field, concluding that with the refined methods now available a wider rangeof meaningful aberrations will be uncovered. 相似文献
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Changes are reported of particle size distribution, organic carbon and nitrogen values, cation exchange capacity and exchangeable cation populations, and in iron and aluminium patterns as a result of adding varying rates of acid peat debris to a mineral topsoil. Up to 3 cm of peat had beneficial effects on soil chemical and physical properties but 5 to 8 cm was sufficient to cause considerable acidification, release of Fe and other ions from primary minerals and the development of an iron seam (or pan) which contains up to 7 per cent free iron. Greater thickness of peat (up to 30 cm) caused soil reaction to drop to pH 4 or less and produced so much humic acids as to inhibit iron precipitation and to facilitate its removal from the profiles. The effects of soil moisture on the pattern of peat humification in the deeper additions (20–30 cm) are also outlined. 相似文献
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BRADLEY R. JACKMAN DVM MS GARY M. BAXTER VMD MS DIPIOMATE ACVS RICHARD E. DORAN DVM MS Dipiomate ACVS DOUGLAS ALLEN DVM MS Dipiomate ACVS ANDREW H. PARKS MA VET MB Dipiomate ACVS 《Veterinary surgery : VS》1993,22(4):285-288
The medical records of 57 horses that had palmar digital neurectomy performed between 1984 and 1990 were reviewed. Neurectomies were performed either by transection and elec-trocoagulation (47 horses) or by the guillotine technique (10 horses). Middle-aged geldings, Quarter Horses, and Thoroughbreds were significantly over-represented when compared with the hospital population. Horses used as hunter/jumpers also appeared to be over-represented. Complications occurred in 17 (34%) of the 50 horses for which follow-up information was obtained. Recurrence of heel pain was the most common complication (14 horses). Palpable painful neuromas were detected in three horses. One year after neurectomy, 74% of the horses were sound; this decreased to 63% after 2 years. 相似文献