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71.
S Müller-Hülsbeck J Link H Schwarzenberg KP Walluscheck D Regensburger M Heller 《Canadian Metallurgical Quarterly》1997,122(9):775-80; discussion 781
Percutaneous stent placement has been described for treatment of aneurysms as an alternative to surgical therapy. Literature reports of percutaneous minimal invasive therapy of peripheral aneurysms shall be reviewed and compared with our own results. Six male patients (51-69 years) with femoropopliteal occlusions related to aneurysms were treated percutaneously. In two cases Wallstents and in four cases polyester-covered nitinol stents were applicated. A clinical investigation including doppler-ultrasound was performed 24 hrs, 1, 3, 6, 12 and 24 months after the intervention. Stent placement succeeded in all cases. No adjunctive surgical treatment was necessary. Ankle-brachial-index (ABI) improved from 0.22 +/- 0.2 before to 0.74 +/- 0.2 24 hours after the intervention. One patient was lost for follow-up (Wallstent). A decrease of ABI and additional intraarterial angiography revealed stent-graft occlusion within one month (n = 2) and within three months (n = 1). One of these cases was successfully recanalized with local fibrinolysis therapy. In three patients patency of the stent persisted for 24 (+/- 2) months follow-up with three-vessel-supply of the calf. These results warrant further investigations for this minimal invasive method of percutaneous stent deployment as an alternative to surgical bypass treatment of femoropopliteal aneurysms. Time of hospitalization was reduced. At this time, surgical treatment of peripheral vascular aneurysms is gold standard. 相似文献
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OBJECTIVES: The aim of this investigation was to study the glomerular and tubular effects of low doses (15 mg) of methotrexate in patients with rheumatoid arthritis with and without combined treatment with aspirin (2 g single dose). METHODS: Renal function was measured by the plasma clearance of EDTA labelled with chromium-51 (51Cr-EDTA) and mercaptoacetyltriglycine labelled with technetium-99m (99mTc-MAG-3). RESULTS: Clearance of 51Cr-EDTA was reduced from 98 (6) to 87 (5) ml/min (mean (SEM)) for patients receiving methotrexate only and further reduced to 76 (5) ml/min for patients receiving methotrexate and aspirin. This effect was reversible as 51Cr-EDTA increased to 85 (6) ml/min during continued treatment with methotrexate alone. Clearance of 99mTc-MAG-3 also decreased from 366 (18) to 315 (17) ml/min in patients receiving methotrexate alone and further to 295 (17) ml/min during treatment with aspirin and methotrexate. Continued treatment with methotrexate alone resulted in a further decrease in the 99mTc-MAG-3 clearance to 253 (17) ml/min. CONCLUSIONS: The study shows that treatment with low doses of methotrexate particularly when combined with aspirin affects glomerular and tubular function. These effects may be of clinical importance and renal function should therefore be monitored with more sensitive methods than serum creatinine as this may not reflect these changes. 相似文献
75.
H. Ö. Özbelge T. F. Al-Fariss A. M. Abdulrazik 《Nutrient Cycling in Agroecosystems》1993,34(3):217-222
There is an appreciable amount of carbonaceous sedimentary phosphate deposits in the northern Africa and the Middle East which are expected to gain importance in the near future because of the depletion of the deposits in Florida. In many of the regions where phosphate deposits are found there is a shortage of fresh water, and sea is not very far. The use of sea water instead of fresh water in flotation of carbonaceous phosphate rock is successfully demonstrated. Thus an appreciable reduction in the operating cost and an ample amount of saving in the fresh water resources of the region is expected. 相似文献
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AA Panteleyev R Paus R Wanner W Nürnberg S Eichmüller R Thiel J Zhang BM Henz T Rosenbach 《Canadian Metallurgical Quarterly》1997,108(3):324-329
Treatment of rats with phenytoin (DPH), an anti-epileptic drug, results in lower tissue thyroid hormone (TH) levels and interferes with the metabolic pathway of TH. To test the hypothesis that DPH affects the enterohepatic cycle of TH and, thus, the kinetics of TH turnover, we performed a kinetic experiment (three-compartment analysis) and a steady-state, double-isotope equilibrium experiment in rats treated for 3 weeks with DPH (50 mg/kg body weight per day) and in untreated controls. This included measurements of TH and TH metabolite levels, as well as the activities of enzymes involved in the TH metabolic pathway. DPH treatment resulted in a decrease in the production of thyroxine (T4) (by 25%) and tri-iodothyronine (T3) (by 37%), a decrease in the T3 concentration in all three pools, and a redistribution of T4 from the fast to the slow pool. The amount of T4 increased in intestinal contents and feces by 66% and 71% respectively. Expressed as a fraction of daily TH disposal, fecal loss of T4 was enhanced from 10 to 23% and that of T3 from 16 to 21%. An increase in T4 and T3 UDP-glucuronyltransferase activities was observed, suggesting that the increased fecal loss of T4 and T3 is secondary to an increased biliary output of their glucuronides. The reduced secretion of TH and increased fecal clearance during DPH treatment can lead in the long run to depletion of TH stores. 相似文献
78.
Novel compounds RETSb2 have been prepared and characterized for T Cu (RE rare earth from La to Lu), Ni (RE La to Ho), Pd (RE La to Tb) and Au (RE La to Sm). From X-ray powder diffraction analyses all compounds were found to crystallize as the ZrCuSi2 type. Magnetic susceptibilities were generally measured in the temperature range from 4 to 100 K. YCuSb2 and LaTSbz are temperature-independent paramagnets. RETSb2 compounds are found to order antiferromagnetically below T = 20 K. PrPdSb2 and TbPdSb2 undergo metamagnetic transitions, whereas PrCuSb2 and ErCuSb2 are simple ferromagnets. The Sm-containing compounds are typical Van Vleck paramagnets owing to the closely spaced multiplets. 相似文献
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