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51.
Meniscal transplantation using fresh and cryopreserved allografts. An experimental study in goats. 总被引:6,自引:0,他引:6
D W Jackson C A McDevitt T M Simon S P Arnoczky E A Atwell N J Silvino 《The American journal of sports medicine》1992,20(6):644-656
A comparative study of three subgroups of meniscal transplants was undertaken in the goat model: Group 1 (autograft) involved removal and immediate reimplantation of the meniscus; Group 2, fresh meniscal allografts; and Group 3, cryopreserved (30 days) meniscal allografts. Six months after surgery, tissues were evaluated for gross degenerative changes, proteoglycan concentration (as assessed by uronic acid), water content, vascularity, histology, and cell viability. The contralateral knee served as control for all comparisons. There was no statistical difference in the amount of arthritis present and all transplants demonstrated an essentially normal peripheral vascularity compared to controls. Sections revealed reduced numbers of cells in the central portions of the transplanted menisci and these viable cells demonstrated different behavior in multiplication in tissue culture compared to contralateral controls. Grossly and microscopically, the implanted menisci differed little from the controls. The measurement of proteoglycan concentration and water content of the transplanted meniscal cartilage suggest alterations that may affect the long-term mechanical properties. The autograft specimens showed the water content was very slightly increased (3% to 6%), while the proteoglycan concentration was increased (42% in terms of uronic acid). In contrast, the water content of the fresh allograft group and the cryopreserved group was increased 12% to 24%. Proteoglycan concentration in these groups was decreased up to 56% in portions of some menisci compared to controls. Fresh and cryopreserved meniscal allografts showed peripheral healing, revascularization, cellularity, and incorporation, and grossly appeared good at 6 months in the goat model. The biochemical changes in the extracellular matrix at 6 months raises questions on the long-term function of these transplanted menisci. 相似文献
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This exploratory study examined the family environment of ten families, each with a physically disabled adolescent and at least one non-disabled adolescent. Family members completed the Moos Family Environment Scale (FES) and discussed with the interviewer their experiences as a family. Blind and independent ratings on the FES by social workers involved in the study provided a comparison with the families' self ratings. Family ratings on the FES gave no indication of distress, but showed slightly higher than average emphasis on cohesion and achievement orientation. Social work ratings, in contrast, indicated elevated levels of conflict, achievement orientation, and control. In this report, no attempt is made to generalize these specific findings to all families with disabled adolescents. Rather, results are interpreted, in the light of findings in the recent literature, to underscore the need for better designed research and to alert professionals to the danger of imposing the prevalent dysfunctional view upon families with disabled children and adolescents. 相似文献
55.
Protective effects of cyclophosphamide, cyclosporin A and FK506 against antigen-induced lung eosinophilia in guinea-pigs. 下载免费PDF全文
A close association has been recognized between activated T cells and eosinophils in asthma, albeit circumstantial. The present study attempted to investigate this relationship in an animal model of lung eosinophilia using the new generation of T cell-selective immunosuppressants, cyclosporin A and FK506, compared with the myelotoxic immunosuppressive agent cyclophosphamide. Antigen challenge of ovalbumin-sensitized guinea-pigs resulted in a lung eosinophilia which was assessed by bronchoalveolar lavage. All three agents caused a marked suppression of lung eosinophilia at 24 h post-challenge when the compounds were administered at the time of sensitization but not when administered for 3 days before lavage. However, the lung eosinophilia at 72 h post-challenge was reduced significantly by FK506 and by cyclophosphamide, but not by cyclosporin A, when the drugs were administered for 3 days, before lavage. These results strongly suggest the involvement of T cells in antigen-induced late phase (72 h) eosinophilia in guinea-pigs but not at 24 h. The effects of cyclophosphamide were always associated with a reduction in circulating white cell counts, whereas cyclosporin A and FK506 showed no myelotoxic properties. These results suggest the potential therapeutic use of selective, non-cytotoxic immunosuppressive agents in asthma. 相似文献
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W Kepron C J Jackson A H Sehon 《International archives of allergy and applied immunology》1987,82(3-4):468-470
Newborn mongrel dogs were sensitized with conjugates of ovalbumin (OA) and 2,4-dinitrophenol (OA-DNP3) in the presence of Al(OH)3 to produce high levels of anti-OA and anti-DNP IgE antibody. At 4-6 months of age, when anti-DNP and anti-OA antibody levels reached titers of 64 by passive cutaneous anaphylaxis, the dogs underwent separate inhalation and intravenous challenges with conjugates of DNP and bovine gamma globulin (DNP15-BGG) and OA. Inhalation challenge with DNP15-BGG and OA resulted in 5- and 10-fold increases in airflow resistance, respectively. Intravenous challenge with either DNP15-BGG or OA produced profound anaphylaxis with 60-80% decreases in blood pressure, cardiac output and regional blood flows in the carotid, superior mesenteric and renal arteries, and the distal aorta. Treatment of sensitized dogs with 5 doses of 20 mg of conjugates of DNP and polyvinyl alcohol (DNP2-PVA) on alternate days resulted in suppression of anti-DNP IgE antibody production; abrogation of established airway and vascular anaphylactic sensitivities; no change in regional blood flows, and no effect on sensitivities to challenge with OA. 相似文献
60.
L. Rosenberg M.D. I. T. Jackson D. Sharpe J. Weiss 《European journal of plastic surgery》1987,9(4):158-159
Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve. 相似文献