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The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated. 相似文献
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RN Jones MA Pfaller SA Marshall RJ Hollis WW Wilke 《Canadian Metallurgical Quarterly》1997,29(3):187-192
From March 1989 to March 1993, six athletic patients were treated in our institution by thrombolytic therapy for acute effort axillary-subclavian vein thrombosis in thoracic outlet syndrome. Mean age of these patients was 20 (range 14 to 27). An in situ infusion with urokinase (2,500 U/kg/h) and Heparin (100 U/kg/12 hours) was given during 64 hours (Range 14 to 72). Phlebography showed a complete reperfusion in three cases (the treatment began within an average period of 5.6 days), partial reperfusion in two cases (the treatment began within an average period of 8.5 days). In one case there was no reperfusion on phlebography: treatment began within an average period of 15 days. For this patient, a venous axillo-jugular bypass graft was performed. In all cases, there was no bleeding complication. A trans-axillary first rib resection was done three months later. Mean follow up was 31 months (range: two to 51 months). All patients recovered their previous physical status. Echo-Doppler exam showed normal subclavian vein flow in four cases, partial occlusion in one case and a total occlusion of the subclavian vein flow in one case. In this last case, the thrombolytic therapy failed to restore the permeability of the subclavian vein. Bypassgraft was patent. Axillary-subclavian vein thrombosis seen within a period of seven days should be treated by local thrombolytic therapy using urokinase and heparin. 相似文献