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121.
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy. 相似文献
122.
Lymphocyte stimulation in mixed kidney cell-leukocyte cultures (MKLC) has been investigated in a canine model. Canine kidney cells were obtained by perfusion trypsinization. Cultured kidney cells, which appeared to be of epithelial origin by several criteria, have been used as stimulator cells. Maximal stimulation was obtained in the MKLC and mixed leukocyte culture (MLC) at stimulator to responder (S:R) cell ratios of 1:20 and 1 1/2:1, respectively. Lymphocyte proliferation has been observed in cultures with kidney cells in S:R cell ratios lower than 1:20. Stimulation has not been observed in MLCs at these low ratios. The addition of graded numbers of kidney cells of the responder to a one-way MLC inhibited the response gradually. The fact that kidney cells have both strong stimulator capacities and inhibitor capacities could explain the lower optimal S:R ratio. Lymphocyte stimulation has not been obtained in mixed kidney leukocyte cultures between major histocompatibility complex (MHC)-identical closely bred animals. The nature of the antigens present on canine kidney epithelial cells stimulatory to allogeneic lymphocytes is discussed. 相似文献
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Silica (4 mg/i.v.) and Carragheenan (20 mg/i.p.) were shown to be capable of weakening hybrid resistance in the spleen whereas no improved growth was observed in the femoral bone marrow. Histological data did not indicate that the agents in the doses used caused significant macrophage mortality. It was concluded that the weakening effect of the agents was not due to death of the effector cells but possibly to a stimulation of the mononuclear phagocytic system in the spleen. Cyclophosphamide (250 mg/kg) induced a weakening of hybrid resistance which was observed both in the spleen and the femoral bone marrow. Experiments with the alkylating agent Busulphan and with Vinblastin showed that both agents were only capable of inducing a moderate stimulation of growth of the transplant in the spleen. A direct specific influence of cyclophosphamide on the microenvironment was proposed. Xenogeneic resistance was studied by transplantation of rat bone marrow to mice. Silica and cyclophosphamide were shown to be capable of inducing a weakening of the resistance in the spleen. The development of the graft in the femoral bone marrow did not appear to be affected by the administration of silica or cyclophosphamide. 相似文献
128.
Significantly prolonged canine renal allograft survival can be obtained by donor pretreatment with procarbazine hydrochloride and methylprednisolone. This is thought to be caused either by a reduced antigenicity of the graft or by a local immunosuppressive effect by drugs transplanted with the graft. In this study a decrease in the number of peripheral donor T and B lymphocytes was observed at the time of procuring. Leukocytes harvested from dogs pretreated with a combination of procarbazine hydrochloride and methylprednisolone showed a decrease in their ability either to stimulate or respond to mixed leukocyte cultures (MLCs). Complete restoration of MLC responses was obtained however by purification and washing of these leukocytes. Sera of pretreated animals were not able to reduce MLC responses. It was concluded that drug metabolites in or on the cells were apparently responsible. A local inhibition of the immunocompetence of host lymphocytes by small amounts of transplanted drug metabolites in or on the graft cells might be responsible for the beneficial effect of donor pretreatment with procarbazine hydrochloride and methylprednisolone. Furthermore, this postulation explains the abrogation of prolonged survival of pretreated grafts after systemic administration of nontreated donor blood or donor leukocyte-free blood, as we reported earlier. 相似文献
129.
目的:研究早期慢性肾病患者的血管内皮功能损害程度及其与肾脏病理损伤的关系。方法:60例研究对象分为3组:A组为20例正常对照组;B组为20例早期慢性肾病患者血压正常组;C组为20例早期慢性肾病患者肾性高血压组。对各组患者应用高频超声检测肱动脉充血前后管径变化率,评价早期慢性肾病患者血管内皮功能损害程度。对病例组行超声引导下穿刺活检,并对肾组织损伤程度行半定量积分,分析血管内皮功能与年龄、血压、肾脏病理损伤的关系。结果:①C组血流介导的血管舒张功能(Flow-mediated dilation,FMD)低于A组和B组(P<0.05),A组与B组之间FMD无差异性(P>0.05);②FMD与收缩压、肾小球损伤积分、肾间质损伤积分有相关性(P<0.05),与年龄、舒张压无相关性(P>0.05)。结论:①肾性高血压患者在肾功能损害之前已经存在血管内皮功能的异常;②血管内皮功能紊乱对肾脏的病理损伤有一定的促进作用;③高频超声早期检测慢性肾病患者的血管内皮功能有重要的临床意义。 相似文献
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