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Ascites often contributes to patient morbidity and discomfort. When refractory to medical management, it has been managed with repeated paracentesis, implantable ports for drainage, or diversion to the urinary bladder. Peritoneovenous shunt insertion has been a technique that was traditionally performed only by surgeons but is now within the realm of interventional radiologists. Its advantage is that protein-rich ascitic fluid is returned to the intravascular compartment. This retrospective study elaborates on the successes and problems encountered during shunt insertion in our first 13 patients. Two patients are well with a functioning shunt at 14 and 32 weeks. In 6 the shunt functioned until the patients death from the underlying malignancy. Two required revision with variable success and in 2, shunt function could not be salvaged. There was one procedure-related mortality. Radiological insertion of these shunts is feasible and should be considered for selected patients. Options are available for assessment and salvaging of dysfunctional shunts.  相似文献   
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Pelvic kidneys are uncommon anomalies rarely utilized in kidney transplantation. We describe a successful case of living-donor transplantation using a pelvic kidney in a 17-month-old infant with congenital renal dysplasia. The recipient had exhausted all options for renal replacement therapy, and urgent transplantation was considered a life saving treatment.  相似文献   
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The critical role of hyperglycemia in the genesis of diabetic nephropathy has been established by cell culture studies, experimental animal models, and clinical trials. Certain cytokines and growth factors have been identified as likely mediators of the effects of high ambient glucose on the kidney, but prominent among these is TGF-beta, a prototypical hypertrophic and fibrogenic cytokine. Overexpression of TGF-beta has been demonstrated in the glomerular and tubulointerstitial compartments of experimental diabetic animals. The TGF-beta receptor signaling system is also triggered, as evidenced by upregulation of the TGF-beta type II receptor and activation of the downstream Smad signaling pathway. Treatment of diabetic mice with neutralizing anti-TGF-beta antibodies prevents the development of renal hypertrophy, mesangial matrix expansion, and the decline in renal function. Antibody therapy also reverses the established lesions of diabetic glomerulopathy. These studies argue strongly in support of the hypothesis that overactivity of the TGF-beta system in the kidney is a crucial mediator of diabetic renal hypertrophy and mesangial matrix expansion.  相似文献   
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This study aimed to quantify the accuracy and precision of a method for in vivo measurements of lead in bone using L-shell x-ray fluorescence (LXRF), the former via comparison with independent measurements of lead in bone obtained using electrothermal atomic absorption spectrometry (AAS) following acid digestion. Using LXRF. the lead content of adult human cadaver tibiae was measured, both as intact legs and as dissected tibiae with overlying tissue removed, the latter at several proximal-distal locations. After LXRF, each tibia was divided into nine cross-sectional segments, which were further separated into tibia core and surface samples for AAS measurement. The proximal-distal variability of AAS-measured core and surface tibia lead concentrations has been described elsewhere (the lead concentration was found to decrease towards both ends of the tibia). The subjects of this paper are the proximal-distal variability of the LXRF-measured lead concentrations, the measurement uncertainty and the statistical agreement between LXRF and AAS. There was no clear proximal-distal variability in the LXRF-measured concentrations; the degree of variability in actual tibia lead concentrations is far less than the LXRF measurement uncertainty. Measurement uncertainty was dominated by counting statistics and exceeded the estimate of lead concentration in most cases. The agreement between LXRF and AAS was reasonably good for bare bone measurements but poor for intact leg measurements. The variability of the LXRF measurements was large enough, for both bare bone and intact leg measurements, to yield grave concerns about the analytical use of the technique in vivo.  相似文献   
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The aim of this study was to validate 109Cd-based K-shell x-ray fluorescence measurements against atomic absorption spectrometry (AAS) measurements of core and surface tibia lead. The lead content of nine adult human cadaver tibiae was measured using 109Cd-based K-shell x-ray fluorescence (XRF) spectrometry and the results compared to measurements obtained using electrothermal atomization atomic absorption spectrometry following acid digestion. Each tibia was divided into nine cross-sectional segments, which were further separated into tibia core and surface samples for the AAS analytical measurements. Proximal-distal variability in tibia lead concentration as determined by AAS was previously described for both surface and core segments and was found to decrease towards the ends of the tibia, in contrast to XRF in which lead was found to increase towards the tibia ends. The effect of this contrasting behaviour on the agreement between XRF and AAS measurements was examined. Lead concentrations determined by AAS ranged from 3 to 19 microg of lead per gram of dry weight bone (microg g(-1)) for tibia core and from 5 to 32 microg g(-1) for tibia surface. Lead concentrations determined by XRF ranged from 2 to 35 microg g(-1) dry weight. No statistically significant difference was found between mean XRF-measured concentrations and mean surface lead concentrations measured by AAS, but XRF significantly overestimated tibia core lead concentrations by between 5 and 8 microg g(-1).  相似文献   
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