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排序方式: 共有485条查询结果,搜索用时 15 毫秒
11.
BT Heelan S Osman A Blyth L Schnorr T Jones AJ George 《Canadian Metallurgical Quarterly》1998,66(8):1101-1103
BACKGROUND: We investigated the potential of predicting allograft rejection by measuring the ability of graft-infiltrating cells to take up 2-[18F]fluoro-2-deoxyglucose ([18F]FDG). This molecule is a positron emitting glucose analogue that is taken up by metabolically active cells and can be detected using positron emission tomography. METHODS: Uptake of [18F]FDG during an alloresponse was measured both in vitro in mixed lymphocyte cultures and in vivo using allogeneic and syngeneic skin grafts. RESULTS: Uptake of [18F]FDG was seen in a mixed lymphocyte reaction. Using a mouse skin graft model, we found that mean [18F]FDG uptake was 1.5-2 times higher in allografts than in syngeneic grafts; the increase in uptake correlated with the level of T-cell infiltrate seen histologically. CONCLUSION: Assessing the metabolic activity of graft-infiltrating cells with [18F]FDG may be useful in the prediction of graft rejection episodes. 相似文献
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The effectiveness ofLeucaena leucocephala (Lam.) de Wit, prunings as N source for maize (Zea mays L.) was evaluated in field and pot trials at Ibadan, southern Nigeria. An N deficient, sandy Apomu soil (Psammentic Usthorthent) was used. The prunings significantly increased N uptake of seedlings and N percentage in ear leaves of maize. High maize gain yield was obtained with application of 10 tons fresh prunings or a combination of 5 tons fresh prunings and N at 50 kg ha–1. The prunings as N source, appeared to be more effective when incorporated in the soil than when applied as mulch. In the pot trial, prunings applied two weeks before planting was more effective than when applied at time of planting maize. Under screen house conditions, the apparent N recovery from prunings with early incorporation about equals that of fertilizer N. 相似文献
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B Balasa JD Davies J Lee A Good BT Yeung N Sarvetnick 《Canadian Metallurgical Quarterly》1998,161(8):4420-4427
IL-10 is essential for an early phase of diabetes in nonobese diabetic (NOD) mice, but later becomes protective against its development. The mechanism by which IL-10 mediates the pathway to diabetes in these mice is unknown. Herein, we dissected the cellular and costimulation requirements for diabetes in transgenic (tg) NOD mice that expressed IL-10 in their pancreatic islets (IL-10-NOD mice). We found that IL-10 alone did not cause diabetes because the offspring (IL-10-NOD-scid mice) from back-crosses of IL-10-NOD mice with NOD-scid mice had no diabetes. Moreover, these IL-10-NOD-scid mice were free of lymphocytic infiltration. Treatment of IL-10-NOD mice with depleting anti-CD4 mAb or control mAb had no effect on diabetes. Surprisingly, depletion of CD8+ T cells by treatment with the corresponding mAb inhibited diabetes without attenuating insulitis, demonstrating a critical role for CD8+ T cells in the disease process. Interestingly, B cell-deficient IL-10-NOD mice readily developed diabetes with kinetics and incidence similar to those observed in wild-type mice, demonstrating that B lymphocytes as APCs were not required in the disease process. Administration of anti-CD40 ligand (CD40L) mAb did not prevent disease, indicating that CD40/CD40L costimulation is not required for diabetes in IL-10-NOD mice. Immunization of IL-10-NOD mice with CFA or heat-shock protein 65, known to block diabetes in NOD mice, had no effect on their diabetes. We demonstrate that IL-10 contributes early to the pathology of diabetes via a CD8+ T cell pathway, eliminating the requirement for B lymphocytes and CD40-CD40L costimulation. Our findings provide a mechanism for the participation of IL-10 in the early development of diabetes. 相似文献
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The efficacy of plasmid DNA encoding cytokine administered by different routes, systemic or surface exposure, was evaluated and compared for their modulating effects on subsequent lesions caused by infection with herpes simplex virus (HSV). Systemic or topical administration of both interleukin-4 (IL-4) and IL-10 DNA but not IL-2 DNA caused a long-lasting suppression of HSV-specific delayed-type hypersensitivity response. IL-4 or IL-10 DNA preadministration also modulated the expression of immunoinflammatory lesions associated with corneal infection of HSV. Suppression of ocular lesions required that the DNA be administered to the nasal mucosa or ocular surfaces and was not evident after intramuscular administration. The modulating effect of IL-10 DNA was most evident after topical ocular administration, whereas the effects of IL-4 DNA given by both routes appeared to be equal. Preexposure of IL-4 DNA, but not IL-10 DNA, resulted in a significant change in Th subset balance following HSV infection. Our results indicate that the modulating effect of IL-4 or IL-10 DNA may proceed by different mechanisms. Furthermore, our results suggest that surface administration of cytokine DNA is a convenient means of modulating immunoinflammatory lesions. 相似文献
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Prof. Dr. Hans-René Bjørsvik Prof. Dr. Bjørn Tore Gjertsen Dr. Vijayaragavan Elumalai 《ChemMedChem》2020,15(10):862-870
A previously designed and developed 12-step total synthesis that includes [1,1′-biphenyl]-2-amine and carbazole intermediates and that ultimately produces the carbazole alkaloid carbazomycin G was exploited as a screening compound library with the goal of identifying potential lead compound(s) with cytotoxic effect. These compounds were investigated by using in-vitro tests involving the two human cell lines HL-60 and MOLM-13, which both model acute myeloid leukaemia (AML). The in-vitro biological test results were used together with the molecular structures of the various intermediates in a concise SAR analysis. Several of the intermediates revealed cytotoxicity (IC50<10−4 M), although the final natural product carbazomycin G did not reveal cytotoxicity versus the two said human cell lines. 相似文献
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We examined whether IL-2 regulates alloimmune responses by studying allograft survival in wild-type (IL-2+/+) and IL-2 gene-knockout (IL-2-/-) mice. The acute rejection of vascularized, cardiac allografts and the generation of allospecific CTLs were not impaired in the absence of IL-2. In contrast, blocking the B7-CD28 T cell costimulation pathway with CTLA4Ig induced long-term allograft survival (> 100 days) in IL-2+/+ recipients but failed to do so in IL-2-/- mice or in wild-type mice that had been treated with IL-2-neutralizing Ab around the time of transplantation. Allografts rejected by IL-2-/- recipients exhibited extensive mononuclear cell infiltrates despite CTLA4Ig administration. In vivo allostimulation in the absence of IL-2 led to exaggerated T lymphocyte proliferation and impaired apoptosis of activated T cells in untreated and CTLA4Ig-treated mice. These findings indicate that endogenous IL-2 is required for the induction of long-term allograft survival, and that IL-2 regulates alloimmune responses by preparing activated T lymphocytes for alloantigen-induced apoptosis. 相似文献
20.
M Gagner A Pomp BT Heniford D Pharand A Lacroix 《Canadian Metallurgical Quarterly》1997,226(3):238-46; discussion 246-7
One hundred consecutive laparoscopic adrenal procedures for a variety of endocrine disorders were reviewed. There was no mortality, morbidity was 12%, and conversions was 3%. During follow-up, none had recurrence of hormonal excess. Laparoscopic adrenalectomy is the procedure of choice for adrenal removal except in carcinoma or masses > 15 cm. OBJECTIVE: The authors evaluate the effectiveness of laparoscopic adrenalectomy for a variety of endocrine disorders. SUMMARY BACKGROUND DATA: Since the first laparoscopic adrenalectomy was performed in 1992, this approach quickly has been adopted, and increasing numbers are being reported. However, the follow-up period has been too short to evaluate the completeness of these operations. METHODS: One hundred consecutive laparoscopic adrenal procedures from January 1992 until November 1996 were reviewed and followed for adequacy of resection. RESULTS: Eighty-eight patients underwent 97 adrenalectomies and biopsies. The mean age was 46 years (range, 17-84 years). Indications were pheochromocytomas (n = 25), aldosterone-producing adenomas (n = 21), nonfunctional adenomas (n = 20), cortisol-producing adenomas (n = 13), Cushing's disease (n = 8), and others (n = 13). Fifty-five patients had previous abdominal surgery. Mean operative time was 123 minutes (range, 80-360 minutes), and estimated blood loss was 70 mL (range, 20-1300 mL). There was no mortality, and morbidity was encountered in 12% of patients, including three patients in whom venous thrombosis developed with two sustaining pulmonary emboli. During pheochromocytoma removal, hypertension occurred in 56% of patients and hypotension in 52%. There were three conversions to open surgery. The average length of stay has decreased from 3 days (range, 2-19 days) in the first 3 years to 2.4 days (range, 1-6 days) over the past 16 months. During follow-up (range, 1-44 months), two patients had renovascular hypertension and none had recurrence of hormonal excess. CONCLUSION: Laparoscopic adrenalectomy is safe, effective, and decreases hospital stay and wound complications. Prior abdominal surgery is not a contraindication. Pheochromocytomas can be resected safely laparoscopically despite blood pressure variations. Venous thrombosis prophylaxis is mandatory. The laparoscopic approach is the procedure of choice for adrenalectomy except in the case of invasive carcinoma or masses > 15 cm. 相似文献