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991.
The surgical treatment of predominantly venous defects   总被引:1,自引:0,他引:1  
The predominantly venous defects consist of the truncular forms, as there is aplasia or obstruction in the truncular dilatation; and they consist of the extratruncular forms as there are the infiltrating ones and the limited ones, according to the Hamburg classification. The web or membranous obstruction of the inferior vena cava (IVC), dilatation or aneurysm of the jugular vein, infiltrating "cavernous angioma" and localized venous defects are the main lesions of those classifications reported in this communication. Jugular dilatation and localized extratruncular lesions have had good therapeutic results. Webs of the IVC can be treated by membranectomy, either by finger, transcardially, or balloon, percutaneously, and cavo- or mesoatrial shunt; however, membranectomy, along with cavoplasty as a radical treatment for such an entity, is advocated by the authors. The infiltrating extratruncular form is the unsolved important issue concerning its thorough resection. Skin graft taken from a resected tissue mass through a reversal split thickness skin graft by a drum type dermatome, removal of the lesion along with muscle layer(s), and staged operations are recommended.  相似文献   
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Clinical-cytogenetic correlations were assessed in 79 patients with transitional cell carcinomas of the bladder to whom cytogenetic analysis of the primary tumor had been successful. High-grade (G2+G3) and high-stage (T2-T4) tumors had in general a higher ploidy level and contained more marker chromosomes, including multiple markers, compared to low-grade (G0+G1) and low stage (Ta+T1) tumors. The early recurrence rate (within 7 months) was significantly higher (p<0.05) in patients whose tumors contained marker chromosomes compared to cases without markers. Also, a significantly higher proportion of patients with marker chromosomes died due to their disease during the study period (follow-up time 30 months) compared to those without markers (84% versus 16%, p<0.005). The results confirm and extend previous studies showing that cytogenetic findings may be an important prognostic indicator in bladder cancer patients.  相似文献   
994.
We have compared the specific activities of Cu/Zn superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in a vinblastine sensitive human T-lymphoblastic cell line (CCRF-CEM) and its multiple drug resistant (MDR) counterpart cell line (CEM/VLB100), which over-expresses P-glycoprotein (PGP). We have found that the specific activity Cu/Zn SOD was consistently 38% increased in CEM/VLB100 cells compared with CCRF-CEM cells. In contrast, the activities of CAT and GSH-Px were similar in the two cell lines. These results suggest that MDR in CEM/VLB100 is a complicated phenotype which not only involves a PGP mechanism, but also a SOD protection mechanism against drug-mediated O2.- cytotoxicity.  相似文献   
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