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991.
Extrarenal Wilms tumor occurring in the inguinal canal   总被引:2,自引:0,他引:2  
We report an unusual case of extrarenal Wilms tumor discovered incidentally during routine inguinal orchiopexy. The world literature and embryological implications of Wilms tumor in the inguinal canal are reviewed.  相似文献   
992.
The authors describe a rapidly growing soft tissue tumor of predominantly histiocytic composition in an 8-year-old child. The tumor cells were identified as elements of the mononuclear phagocyte system by histologic, histochemical, immunologic, and electron microscopic study. Despite the presence of a minor fibroblastic component, the tumor did not conform to established criteria for a diagnosis of malignant fibrous histiocytoma. Formation of frequent desmosome-like intercellular junctions raised the possibility of dendritic reticulum cell differentiation, since the latter cells seem to be the only elements of the mononuclear phagocyte system that display such specialized cell junctions. The results of immunostaining were discrepant with those reported for normal dendritic reticulum cells, but the currently available information makes it doubtful that the entire neoplastic spectrum of dendritic cell differentiation can currently be diagnosed in surgical pathology.  相似文献   
993.
The purpose of this study was to clarify the main contributory factor of nifedipine-induced gingival overgrowth either by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) or interleukin-1beta (IL-1beta). Human gingival fibroblasts from healthy tissues and nifedipine-induced gingival overgrowth tissues were stimulated with nifedipine, IL-1beta, Escherichia coli lipopolysaccharide (Ec-LPS), and Pg-LPS, and the gene expressions were analyzed by RT-PCR. Analysis of the data showed no strong evidence of a synergistic effect of nifedipine and Pg-LPS on IL-6, connective tissue growth factor (CTGF), and type 1 collagen gene expression of either healthy cells or nifedipine-induced gingival overgrowth cells. Among the three stimulants--IL-1beta, Pg-LPS, and Ec-LPS--androgen receptor and IL-6 gene expressions in both the healthy and nifedipine-induced gingival overgrowth groups were strongly up-regulated by the presence of IL-1beta only. Furthermore, the responses to IL-1beta in the nifedipine-induced gingival overgrowth group were stronger than those of the healthy group. It can be concluded that IL-1beta is an important mediator responsible for the higher IL-6 and androgen receptor expression of nifedipine-induced gingival overgrowth cells.  相似文献   
994.
995.
The amyloid beta peptide (Abeta), a mediator of neuronal and vascular degeneration in the pathogenesis of Alzheimer's disease and cerebral amyloid angiopathy may have peripheral actions. Platelets are enriched with Abeta and have been shown to enhance platelet actions. However, the detailed signaling pathways through which Abeta activates platelets have not been previously explored. In this study, we examined the intra-platelet Abeta distribution using a gold labeling technique and noted that Abeta was predominantly localized in the cytoplasm of resting platelets. A marked increase in Abeta-gold labeling in an open canalicular system was observed in collagen-activated platelets. Exogenous Abeta (2-10 microM) stimulated platelet aggregation accompanied by phospholipase Cgamma2 (PLCgamma2) phosphorylation, phosphoinositide breakdown, and [Ca(2+)]i mobilization as well as protein kinase C (PKC) activation. Ro318220, an inhibitor of PKC, suppressed Abeta-induced platelet aggregation, PKC activation, and [Ca(2+)]i mobilization in platelets, suggesting that the PLCgamma2-PKC pathway is involved in Abeta-induced platelet aggregation. In the electron spin resonance study, Abeta (2 and 10 microM) markedly triggered hydroxyl radical formation in platelets. In an in vivo study, Abeta (2mg/kg) significantly shortened the latency for inducing platelet plug formation in the mesenteric venules of mice. In conclusion, we are the first to demonstrate (1) the distribution of Abeta in human platelets; and that (2) Abeta activation of platelets is mediated, at least partially, by the PLCgamma2-PKC pathway; and (3) Abeta triggers thrombus formation in vivo.  相似文献   
996.
M L Chang  C T Chou  C F Lee 《台湾医志》1990,89(4):326-330
Antibodies to type II collagen (Col II) in sera and synovial fluid (SF) were measured with an enzyme linked immunosorbent assay (ELISA) using a solid phase sandwich method. The subjects included: 42 patients with rheumatoid arthritis (RA); 31 cases of osteoarthritis (OA); 10 cases of gouty arthritis; 4 cases of ankylosing spondylitis (AS); 5 cases of systemic lupus erythematosus (SLE); and 44 normal controls. The antigens used to detect antibodies against Col II were in native and heat-treated denatured forms, both of which were purified from chicken sternal cartilage by limited enzyme digestion and differential precipitation with salt. The reactivity to native type II collagen was generally higher than the reaction to the denatured collagen. In sera, significant higher levels of Col II were detected in the different arthritis groups when compared with the normal control group, with the exception of AS. In SF, the Col II was significantly higher in RA than it was in OA (p less than 0.001), while no difference was present between gout and OA (p less than 0.05). When native Col II was simultaneously measured in sera and SF among arthritics, positive rates were both higher among RA (65% and 58%, respectively). Positive rates were only higher in sera among OA (59% in sera and 3% in SF) and were both lower among gouty arthritis. The above findings show that the measurement of Col II is more important in SF than in sera.  相似文献   
997.
Microskin grafting of rabbits with pigskin xenograft overlay   总被引:1,自引:0,他引:1  
Pigskin xenografts were used to replace allografts in microskin grafting (10: 1 expansion ratio) on 15 rabbits. Rabbits were selected randomly for the removal of the overlaid pigskin at days 7, 10 or 14 for the evaluation of the degree of epithelialization. Histological examination of the removed pigskin 7 days after application showed obvious eosinophilic changes in the epidermal cells and pyknotic changes of the nuclei, however in some areas newly formed epidermis could be found. The pigskin became an eschar or slough on day 14. The microskin autografts proliferated and expanded actively under the protection of this overlaid pigskin. The epidermis increased in thickness and with increasing differentiation. The dermal layer was well vascularized with a large number of capillaries and fibroblasts. The wound was covered by the neoepithelium with almost normal skin texture on day 14, by which time the overlaid pigskin became a dry eschar. In areas where the overlaid pigskin was sloughing, the epithelialization of the underlying microskin grafts was not complete at the same time. In these animal studies of microskin grafting, these overlaid pigskin xenografts showed the same effects as those of allografts.  相似文献   
998.
Twenty-six patients with metastatic cancer were entered into a phase I trial of concurrent recombinant interleukin-2 (IL-2) and recombinant interferon-gamma (IFN-gamma). IL-2 was administered as a continuous intravenous infusion for 5 days. IFN-gamma was administered by a daily intramuscular (IM) injection during the 5 days of IL-2 administration. Treatment was repeated twice after 9-day rest periods. After a 2-week rest, patients without evidence of tumor progression were retreated. Natural killer (NK)- and lymphokine-activated killer (LAK)-cell activity were assayed in each patient before treatment, on day 1, and on day 5 of each cycle. Constitutional symptoms occurred in most patients but were not dose-limiting. Other toxicities included hypotension responsive to fluids, transient elevations in liver function tests, erythema/pruritus, eosinophilia, and transient leukopenia/thrombocytopenia. The maximum-tolerated dose (MTD) of the combination was 1 x 10(6) U/m2/d of IL-2 combined with 0.50 mg/m2/d of IFN-gamma. The dose-limiting toxicity was pulmonary manifesting as rales and shortness of breath. The dose of the combination that resulted in the optimal generation of in vivo LAK-cell activity was a dose of at least 0.25 mg/m2/d of IFN-gamma combined with 1 x 10(6) U/m2/d of IL-2. Objective clinical responses were seen in five of 26 patients. These included a partial response of 2 months duration in a patient with non-Hodgkin's lymphoma (NHL), mixed responses in a patient with NHL and two patients with renal cell carcinoma (RCC), and an ongoing assessable response in a patient with bone metastases from RCC. The recommended dose for phase II trials of this combination is 0.50 mg/m2 of IFN-gamma and 1 x 10(6) U of IL-2.  相似文献   
999.
1000.
Background/Purpose: Treatment of adult neglected developmental dysplasia of the hip (DDH) with high dislocation is still not established. The main concern of young patients is leg-length discrepancy (LLD), which leads to limping gait and impaired body image. Such patients usually ask for a minimally invasive treatment that can improve the LLD. Methods: Between 1993 and 2003, 17 patients with neglected DDH with high dislocation (mean age, 22.8 years) were treated by tibial lengthening using the Ilizarov external fixator over an intramedullary nail. The inclusion criteria were unmarried young adults, unilateral lesion, significant limping or unsightly gait with psychologic discomfort, marked shortening > 4 cm with the block test, and benefit from a shoe-lift. Exclusion criteria were patients older than 30 years, hip pain as the chief complaint, and compensated low hip dislocation without significant limping. Results: All 17 patients had eventual bone consolidation without further operation. The mean external fixation index was 14.2 day/cm. Bone formation was good in all patients with a mean consolidation index of 57.7 day/cm. At an average follow-up period of 7.8 years, the limping was much improved from a moderate or severe degree to a mild degree in all patients. No patients had equinus contracture. All patients were satisfied with their treatment results. There were two complications: transient loss of big toe extension and mild wound infection. Conclusion: Tibial lengthening can improve limping in adult patients with neglected DDH and high dislocation with a low morbidity. Lengthening along intramedullary nails can effectively reduce the external fixation time, improve bone formation, and prevent complications.  相似文献   
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