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21.
【摘要】 目的 观察在生理和病理情况下,骨髓来源的干细胞(BMSC)能否分化成肾小管上皮细胞。 方法 绿色荧光蛋白(GFP)标记的C57BL/6转基因小鼠提供骨髓细胞。同种无荧光标记的C57BL/6小鼠100只分为正常对照组、全身照射组、缺血再灌注组、骨髓移植组、骨髓移植+缺血再灌注组。受体鼠的骨髓重建经血液常规检查和流式细胞仪检测确认,并采用荧光组织化学、免疫组织化学等方法观察绿色荧光标记的BMSC在受体鼠肾脏的分布及数量。 结果 全身致死剂量γ射线照射未造成小鼠肾脏组织结构和生理功能的明显改变。骨髓移植后第56、84天的受体鼠肾小管中有少量GFP阳性细胞的存在[(78.75±5.99)%、(79.58±4.60)%],激光共聚焦显微镜进一步证实这些细胞位于肾小管,并表达肾小管上皮细胞特异性的功能蛋白megalin。 结论 在生理和病理情况下,骨髓干细胞均可以向肾小管上皮细胞转分化,参与肾小管上皮细胞的更新,并且在急性肾小管坏死的病理条件下,骨髓干细胞的肾向转化率与肾脏受损程度有关。 相似文献
22.
T. A. Creagh P. A. McLean M. G. Donovan J. J. Walshe D. M. Murphy 《Transplant international》1993,6(1):39-41
Reluctance to use kidneys from older donors (>50 years of age) is based on reports of inferior results. We reviewed our experience with 45 kidneys transplanted from older donors. Primary nonfunction, immediate graft function, and 1-, 2- and 3-year graft survival rates were similar to those obtained with kidneys transplanted from donors aged between 20 and 40 years. Renal function at 1 year (as measured by serum creatinine) was poorer in kidneys from older donors. No beneficial effect with respect to graft survival was noted with cyclosporin therapy compared to conventional immunosuppression; however, the numbers are small. We conclude that kidneys from older donors are a valuable source for transplantation. 相似文献
23.
24.
Martha A. Warpehoski Paul J. Buscemi David C. Osborn Birdwell Finlayson Eugene P. Goldberg 《Calcified tissue international》1981,33(1):211-222
Summary The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found
to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter
ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a “growth
front” on stone surfaces with migration of organic material from the “older” interior. The matrix distribution was not readily
correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations
were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich
surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates
as growth centers. 相似文献
25.
Mikael Hellström Bo Jacobsson Ulf Jodal Jan Winberg Anders Odén 《Pediatric nephrology (Berlin, Germany)》1987,1(3):269-275
This study presents the result of 12–21 years' follow-up in a group of children with neonatal urinary tract infection (onset within 1 month after birth) in whom early renal growth retardation was noted without concomitant classical renal scarring. In all cases the neonatal infection was diagnosed and treated within a few days of onset and the patients were closely supervised thereafter. Renal length, parenchymal thickness and area were measured at urography. At first follow-up (22 children, mean age 4.1 years) a significant reduction of renal parenchymal thickness was noted. Long-term follow-up (18 patients, mean age 17 years) demonstrated a normalization of renal size in the entire group, although less complete in the subgroup with reflux. There were two major findings in the present study. Firstly, renal growth retardation was seen after neonatal infection, both with and without reflux. Secondly, normalization of renal size in previously small kidneys was demonstrated, suggesting that growth retardation can be a reversible phenomenon. The tendency for such normalization was slightly more marked in children without reflux. Reduction of parenchymal thickness without calyceal deformity, therefore, does not necessarily mean irreversible damage, and differentiation between permanent scarring and temporary growth retardation can thus only be made at later follow-up, possibly not until after puberty. The demonstration of renal growth retardation in spite of early diagnosis and treatment emphasizes the great vulnerability of the kidney in the newborn. 相似文献
26.
在综合疗法的基础上加用异搏定3~5天治疗流行性出血热(EHF)发热后期病人41例,在尿蛋白转阴、越期率,特别是越少尿期平明显优于对照组,但对 BUN 水平的影响与对照组无异,异搏定对防治 EHF 急性肾衰具有一定疗效。 相似文献
27.
Annemieke Smit-van Oosten Winston W. Bakker Harry van Goor 《Transplant international》2002,15(12):602-609
Ischemic injury plays an important role in chronic renal transplant failure (CRTF). Down-regulation of ecto-adenosine triphosphatase (ATPase) in combination with up-regulation of ecto-5'-nucleotidase is a hallmark of ischemic injury. We studied the expression of renal ecto-5'-nucleotidase and ecto-ATPase in experimental renal transplantation. Fisher 344-to-Lewis allografted rats were either treated with an angiotensin-converting enzyme inhibitor (ACEi) or left untreated. Lewis-to-Lewis syngrafted rats served as controls. Untreated allografted rats developed proteinuria, glomerulosclerosis, and mild intimal hyperplasia. ACEi completely prevented focal and segmental glomerulosclerosis (FGS) and proteinuria, but significantly enhanced intimal hyperplasia. Untreated allografted rats revealed marked vascular ecto-5'-nucleotidase activity, which increased with ACEi. Vascular ecto-5'-nucleotidase activity was absent in syngrafted animals. Ecto-5'-nucleotidase activity correlated well with intimal hyperplasia. Glomerular ecto-ATPase expression was significantly reduced in untreated allografted rats compared to syngrafted rats and correlated well with the extent of FGS. ACEi prevented reduction in glomerular ecto-ATPase. We found de-novo expression of ecto-5'-nucleotidase at sites of renal intimal hyperplasia. Glomerular ecto-ATPase expression was markedly reduced in allografted rats and was prevented by ACEi. These enzyme expression patterns suggest local ischemic damage in experimental CRTF. 相似文献
28.
目的:比较CT平扫与增强扫描对肝脾肾钝性损伤的诊断能力。方法:回顾性分析临床疑似钝性肝脾肾损伤,并经手术和临床观察证实的CT平扫和增强扫描的患者84例。结果:平扫确定的损伤:肝12例,脾25例,肾5例;平扫可疑损伤:肝22例,脾15例,肾5例。增强确定的损伤:肝32例,脾40例,肾12例(全肾梗塞1例,局限性梗塞3例);对比剂外溢(活动性出血)3例;无可疑损伤。平扫无异常而增强确定有损伤:肝10例,脾5例,肾2例。增强显示的损伤灶比平扫范围明显大、病灶多、界限清楚。结论:CT增强扫描显示肝脾肾损伤明显优于平扫,延时扫描有助于发现活动性出血,应常规增强扫描。 相似文献
29.
Davies S. P.; Webb W. J. S.; Patou G.; Murray W. K.; Denning D. W. 《Nephrology, dialysis, transplantation》1987,2(6):568-572
The second documented case of renal aspergilloma due to Aspergillusflavus is presented. The merits of the medical therapy thatfailed are discussed. Pathological examination showed a nidusof aspergillus around suture material persisting from a pyelolithotomyoperation 2 years before in India. We argue that this was thereason for the failure of the medical therapy. This is the firstcase of its kind reported. 相似文献
30.
苄丙酮香豆素对实验性大鼠肾草酸钙结石形成的影响 总被引:1,自引:0,他引:1
目的:探讨Vit.K拮抗剂苄丙酮香豆素(商品名华法令)对大鼠肾草酸钙结石形成的影响。方法:采用乙二醇饮水和氯化铵灌胃作成石剂,30只Wistar大鼠随机分为对照组(A组)、成石组(B组)、华法令组(C组)。饲养4周后,检测大鼠肾组织钙含量和草酸钙晶体形成、24h尿钙、尿草酸含量及血生化指标。结果:成石组和华法令组肾组织中钙、镁含量,24h尿草酸及尿钙、镁排泄量差异无显著性意义;镜下观察发现:华法令组大鼠肾脏草酸钙结晶形成多于成石组,但组间比较差异无显著性意义。结论:苄丙酮香豆素对大鼠肾草酸钙结石的形成无显著影响。 相似文献