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91.
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
94.
Protective effects of cyclophosphamide, cyclosporin A and FK506 against antigen-induced lung eosinophilia in guinea-pigs.
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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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Abstract: Research indicates that two major forms of partner violence exist, intimate terrorism (IT) and situational couple violence (SCV). The current study (N= 389) used a subgroup of women who responded to the Chicago Women’s Health Risk Study to examine whether type of violence experienced is differentially related to formal (e.g., police, medical agencies, counseling) and informal (e.g., family, friends/neighbors) help seeking. IT victims were more likely to seek each type of formal help but were equally or less likely to seek informal help. Findings can inform both family violence research and the development and implementation of social service programs. 相似文献
99.
Dany Anglicheau Alexandre Lautrette Catherine Scieux Martin Flamant Frédéric Morinet Christophe Legendre 《Nephrology, dialysis, transplantation》2003,18(8):1654-1656
BACKGROUND: Routine cytomegalovirus (CMV)-pp65 antigenaemia monitoring shows that some patients will develop pp65 antigenaemia during valaciclovir prophylaxis or after cessation of treatment. The aim of this pilot study was to evaluate the safety and efficacy of lowering immunosuppression in kidney transplant recipients who exhibit mildly symptomatic CMV infections while on valaciclovir prophylaxis. METHODS: We selected 12 patients who experienced mildly symptomatic CMV infections defined as a positive CMV-pp65 antigenaemia test associated with either neutropenia, asthenia or arthralgia, but no fever. All of them received prophylaxis with valaciclovir for at least 3 months. Testing for CMV-pp65 antigenaemia was performed weekly for 6 months. RESULTS: The mildly symptomatic infections occurred at a median interval of 69 days after transplantation-during prophylaxis in eight cases and after valaciclovir discontinuation in the other four cases. All of them were effectively managed by lowering immunosuppressive therapy, leading to the disappearance of symptoms and CMV antigenaemia reduction. No immunological complication or recurrence of CMV infection or disease was noted. I.v. ganciclovir never became necessary. CONCLUSION: The mildly symptomatic CMV infections occurring in valaciclovir-treated patients may be managed efficiently and without immunologic complication by lowering immunosuppressive therapy. 相似文献
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