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E Cosmi P Litta A Andrisani L Di Lenardo G M Fadda G Ambrosini 《Ultrasound in obstetrics & gynecology》2005,25(4):415-416
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Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
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E Levi G Z Fadda P Thanakitcharu S G Massry 《Journal of the American Society of Nephrology : JASN》1992,3(5):1139-1146
In chronic renal failure (CRF), a multitude of metabolic derangements occur in the pancreatic islets, resulting in impaired glucose-induced insulin secretion. These abnormalities include a rise in the basal level of cytosolic calcium ([Ca2+]i) in the islet, a decrease in their basal and stimulated ATP and ATP/ADP ratio, a reduction in the Vmax of Ca2+ATPase and Na(+)-K+ATPase, and an impaired glucose-induced calcium signal. The sequence of events that lead to these derangements and to the impairment in insulin secretion during the evolution of CRF are not defined. The study presented here examined this issue by measuring the metabolic profile of pancreatic islets weekly during the evolution of CRF over a period of 6 wk. The results show that serum levels of parathyroid hormone (PTH) begin to rise during the first week of CRF. The Vmax of Ca2+ATPase and Na(+)-K+ATPase increased during weeks 1 to 3 of CRF but fell to low levels thereafter. At week 3 of CRF, the basal level of [Ca2+]i began to rise, whereas basal and the stimulated ATP content and ATP/ADP ratio started to fall. Glucose-induced calcium signal, delta[Ca2+]i/basal [Ca2+]i, and insulin secretion became abnormally low between weeks 3 and 6 of CRF. The data allow the following formulation: as serum levels of PTH begins to rise, calcium entry into islets is augmented; this in turn will stimulate the activity of Ca2+ATPase and the Na(+)-Ca2+ exchanger, and hence, calcium extrusion out of the islets is increased. As a result, [Ca2+] remains normal during the first 2 wk of CRF.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献