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51.
Moore J, Tomson CRV, Tessa Savage M, Borrows R, Ferro CJ. Serum phosphate and calcium concentrations are associated with reduced patient survival following kidney transplantation.
Clin Transplant 2011: 25: 406–416. © 2010 John Wiley & Sons A/S. Abstract: The impact of disordered mineral and bone metabolism following kidney transplantation is not well defined. We studied the association of serum phosphate and calcium concentrations, and surrogate measures of arterial stiffness (augmentation index: AIx and Timing of the reflected wave: Tr), with long‐term kidney transplant recipient and allograft survival. Prevalent adult renal transplant patients (n = 270) were prospectively studied over a median 88‐month follow‐up. Detailed demographic, clinical and laboratory data, in addition to both peripheral and central non‐invasive blood pressure measurements, were recorded. Higher serum phosphate and calcium levels were associated with increased all‐cause mortality (HR: 1.21; 95% CI 1.09,1.35, p < 0.001 and HR: 1.22; 95% CI 1.01,1.48; p < 0.04, respectively; adjusted Cox model) and death‐uncensored graft loss (p < 0.001 and p = 0.03, respectively). In addition, serum calcium and phosphate were associated with death‐censored graft loss on univariable analysis (p < 0.001 and p = 0.02, respectively), but did not retain significance on multivariable analysis. AIx and Tr were not associated with mortality or graft loss on multivariable analysis. This is the first report to demonstrate that both higher serum phosphate and calcium levels are associated with increased mortality in kidney transplant recipients. It highlights the need for randomized trials assessing current interventions available for improving disordered mineral–bone metabolism post transplantation.  相似文献   
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自固化磷酸钙人工骨修复四肢骨缺损的初步临床应用   总被引:40,自引:2,他引:40  
目的 研究自固化磷酸钙水泥(ACPC)人工骨修复非负重或低负重部位骨缺损的临床应用。方法 应用ACPC人工骨修复30例患者36处非负重或低负重部位骨缺损,平均年龄26.5岁。骨缺损大小均为15cm^2,骨缺损病因依次为骨折、骨囊肿、骨纤维结构不良、内生软骨瘤和髂骨供骨区等。观察患者术中ACPC固化时间,术后全身及切口局部反应,血钙、磷值变化,X线片和CT扫描。随访平均时间9.4个月。结果 全部患者  相似文献   
54.
Liu HC  Yao CH  Sun JS  Lee CJ  Huang CW  Lin FH 《Artificial organs》2001,25(8):644-654
The cytotoxicity of the synthetic bone substitute composed of tricalcium phosphate and glutaraldehyde crosslinked gelatin (GTG) were evaluated by osteoblast cell culture. In a previous study, the GTG composites were soaked in distilled water for 1, 2, 4, 7, 14, 28, and 42 days, and then the solutions (or extracts) were cocultured with osteoblasts to evaluate the cytotoxicity of GTG composites by alive cell counting. In this study, the extracts were cocultured with the osteoblasts; thereafter, the concentration of transforming growth factor-beta (TGF-beta1) and prostaglandin E2 (PGE2) in the medium was analyzed to strictly reflect the biological effects of GTG composites on the growth of osteoblasts. In order to investigate the osteoconductive potential of the GTG composites on new bone formation in a relative short term, a model of neonatal rat calvarial organ culture was designed prior to animal experiments. Three experimental materials of 4, 8, and 12% GTG composites were evaluated by fetal rat calvarial organ culture for their ability for bone regeneration. Deproteinized bovine and porcine cancellous bone matrixes were used as the controlled materials. All the organ culture units were maintained in cultured medium for 5 weeks. Following the culture period, the morphology of tissue was observed under an optical microscope, and the quantitative evaluation of the new generation bone was determined by using a semiautomatic histomorphometeric method. Except in the initial 4 days, the concentration of TGF-beta1 of 4% and 8% GTG composites was higher than that of the blank group for all the other experimental time periods. The PGE2 concentration for 4% and 8% GTG composites was lower than that of the blank group. It revealed that the 4% and 8% GTG composites would not lead to inflammation and would promote osteoblast growth. The morphology and activity of the osteoblasts were not transformed or changed by the 2 GTG composites. For the 12% GTG composite, the performance of the in vitro condition was inferior to the blank group and the other 2 GTG composites. Although the concentration of TGF-beta1 and PGE2 was gradually back to normal after 14 days, the morphology of the osteoblasts was abnormal with features such as contracted cytoplast structures. The osteoblast was damaged perhaps in the initial stage. We suggested that the 4% and 8% GTG composites should be soaked in distilled water at least for 4 days before medical applications. The 12% GTG composite and the composites with a concentration of glutaraldehyde solution higher than 12% were not recommended as a medical prostheses in any condition. The fetal rat calvaria culture also showed the same results with the analysis of TGF-beta1 and PGE2. From the study, we could predict the results of animal experiments in the future.  相似文献   
55.
The effectiveness of transpedicular calcium phosphate cement (CPC) injection as a new treatment for osteoporotic compression fracture of vertebrae was evaluated by measuring the compressive strength and the mode of failure in vertebrae experimentally injected with CPC. Forty-five human cadaver vertebrae were divided into three groups: a control group; group A, in which CPC was injected into the upper half of the vertebral body; and group B, in which CPC was injected into the whole vertebra. The load-displacement curve characteristically had two peaks in group A, and decreased rapidly after failure in group B. The failure site was the cancellous bone immediately below the cranial endplate in the control group, cancellous bone immediately below the CPC injection area in group A, and in the CPC injection area in group B. Although mechanical strength was greatest in those vertebrae in which the entire cancellous bone was replaced with CPC, the compressive strength of the vertebrae was also increased by partial replacement of cancellous bone with CPC injection. In terms of mode of failure and mechanical gradient with adjacent vertebrae, there were several advantages for those vertebrae in which the cranial half of the cancellous bone was replaced with CPC. Received: May 29, 2000 / Accepted: September 20, 2000  相似文献   
56.
目的对磷酸钙水泥(CPC)填充固定桡骨远端骨折的抗旋转应力进行评价,并与传统的克氏针固定方法进行比较。方法18根人桡骨标本制备桡骨远端骨折伴骨缺损模型,随机分为三组:克氏针固定组、CPC固定组和CPC 克氏针联合固定组。设定扭转速度为5°/min,最大扭转角度为10°时停止。记录扭转刚度、10°内的最大扭矩及所对应的最大扭角。结果在10°的扭转范围内,CPC固定组、CPC 克氏针联合固定组的扭转刚度、最大扭矩均比克氏针固定组大,差异有统计学意义(P< 0.01);最大扭转角度分别为4.3°和5.0°,均比克氏针组(9.6°)小,差异有统计学意义(P<0.01)。CPC固定组与CPC 克氏针联合固定组之间的扭转刚度、最大扭矩及最大扭角差异无统计学意义(P> 0.05)。结论在旋转角度小于4°范围内,CPC的抗旋转固定强度要比克氏针大,超过这个范围,骨水泥就会发生断裂,CPC的有效固定范围比克氏针要小。  相似文献   
57.
Regulation of fibroblast growth factor-23 in chronic kidney disease.   总被引:4,自引:0,他引:4  
BACKGROUND: Fibroblast growth factor-23 (FGF23) is a circulating factor that regulates the renal reabsorption of inorganic phosphate (Pi) and is increased in chronic kidney disease (CKD). The aim of the current investigation was to study the regulation of FGF23 in CKD subjects with various degree of renal function. As such, we analysed the relationship between FGF23, Pi, calcium, parathyriod hormone (PTH), 25(OH) vitamin D3(25(OH)D3), 1,25(OH)2 vitamin D3(1,25(OH)2D3) and estimated glomerular filtration rate (eGFR). METHODS: Intact FGF23 and other biochemical variables were analysed in 72 consecutive adult out-patients with various stages of CKD (eGFR ranging from 4-96 ml/min.) Association studies were performed using linear univariate and multivariate analysis. RESULTS: FGF23 was significantly elevated at CKD stage 4 (266 +/- 315 pg/ml, P < 0.001) and 5 (702 +/- 489 pg/ml, P < 0.001) compared with CKD 1-2 (46 +/- 43 pg/ml). In CKD 4-5 an independent association between log FGF23 and Pi (P < 0.001), 25(OH)D3 (P < 0.05) as well as eGFR (P < 0.01) was observed. In contrast, in CKD 1-3 log PTH (P < 0.05) was the only independent predictor of log FGF23 in multivariate analysis. In CKD 1-5, Pi (P < 0.00001) and log PTH (P < 0.01) were explanatory variables for log FGF23 in multivariate analysis. CONCLUSIONS: We conclude that serum FGF23 increases in CKD 4-5, in parallel with the emerging hyperphosphataemia. Serum Pi is the most important predictor of FGF23 when GFR is less than 30 ml/min. In contrast, our data suggest that Pi may not be an important determinant of FGF23 in normophosphataemic CKD subjects. Finally, the association between FGF23 and PTH in CKD may suggest a co-regulation that remains to be further elucidated.  相似文献   
58.
PURPOSE: We report the evolution of endoscopic treatment of ectopic ureteroceles from the unroofing technique to a novel approach using concomitant ureterocele double puncture and intraureterocele fulguration. We also compare the results of different endoscopic modalities at a single center. MATERIALS AND METHODS: We reviewed the records of 46 children with ectopic ureteroceles who were treated endoscopically between 1995 and 2005. The patients were divided into 2 main groups. Group 1 included 17 patients who underwent common endoscopic treatments, including ureterocele incision (4 patients), single ureterocele puncture (4), and single puncture with insertion of a Double-J stent (9). Group 2 included 29 children who underwent ureterocele double puncture and fulguration of the anterior and posterior walls of the collapsed ureterocele after insertion of a Double-J stent into both punctured sites. We also managed concomitant vesicoureteral reflux by endoscopic injection of tricalcium phosphate ceramic into the subureteral region. RESULTS: Total success rates in group 1 were 0%, 25% and 33% in patients who underwent ureterocele incision, single ureterocele puncture and single puncture with insertion of a stent, respectively. Total success rate in group 2 was 90% (p<0.05). New onset vesicoureteral reflux developed in 8 patients (47%) in group 1, of which 6 were in ureterocele moieties, and in 8 patients (28%) in group 2, with none in a ureterocele moiety (p<0.01). A total of 13 patients (76%) in group 1 required open surgical intervention, compared to 3 (10%) in group 2 (p<0.05). CONCLUSIONS: This new endoscopic approach is highly effective in the treatment of children with ectopic ureteroceles.  相似文献   
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60.
目的:评价参肤外洗方联合克林霉素磷酸酯乳膏治疗细菌性阴道炎的临床疗效及其安全性。方法:共纳入符合观察条件的150例细菌性阴道炎患者,随机分为3组,每组各50例。对照组给予克林霉素磷酸酯阴道用乳膏,治糜康栓组在对照组基础上联合治糜康栓,参肤外洗方组在对照组基础上联合参肤外洗方,疗程均为7 d。观察各组患者的临床疗效、局部不良反应,并追踪调查远期复发率。结果:对照组、治糜康栓组、参肤外洗方组的总有效率分别为74.00%、84.00%、96.00%,参肤外洗方组总有效率明显高于对照组(P0.05);3组的不良反应发生率分别为22.00%、16.00%、6.00%,参肤外洗方组的不良反应明显少于对照组和治糜康栓组(P0.05)。在完成1~3个月的随访患者中,对照组共复发12例、治糜康栓组复发10例、参肤外洗方组复发4例,参肤外洗方组的复发率显著低于对照组和治糜康栓组(P0.05)。结论:参肤外洗方联合克林霉素磷酸酯乳膏治疗细菌性阴道炎,可明显提高临床疗效、降低复发率,且安全性好。  相似文献   
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