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941.
A metropolitan experience with infrainguinal revascularization. Operative risk and late results in northeastern Ohio 总被引:1,自引:0,他引:1
T D Rafferty J C Avellone C J Farrell N R Hertzer F R Plecha R S Rhodes W V Sharp J M Rogers 《Journal of vascular surgery》1987,6(4):365-371
Despite being of fundamental importance, the late results of major arterial reconstruction rarely have been documented throughout a large metropolitan area. In this study of 932 patients entered into the computer registry of the Cleveland Vascular Society, 19 surgeons representing 13 community hospitals and referral centers in Cleveland and Akron report the intermediate-term outcome during a mean interval of 35 months after infrainguinal lower extremity revascularization performed in northeastern Ohio from 1978 through 1982. Operative risk (5%), the early amputation rate (7%), and actuarial 5-year survival (48% to 55%) for patients with rest pain or tissue necrosis were significantly worse (p less than 0.05) than comparable figures (0.6%, 0%, and 77%, respectively) for others who underwent procedures for disabling claudication. Although both materials had similar success above the knee, the cumulative 3-year patency rate of autogenous vein bypass to the distal popliteal (69% to 88%; p less than 0.05) and tibioperoneal arteries (43%; 0.05 less than p less than 0.1) was superior to the results of polytetrafluoroethylene grafts (32% to 50% and 19%, respectively). Moreover, polytetrafluoroethylene grafts required reoperations at three times the rate of vein grafts to maintain limb salvage. 相似文献
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945.
Failure of genetically selected miniature swine to model NIDDM 总被引:2,自引:0,他引:2
Ten young adult miniature swine from a line reported to be genetically selected for glucose intolerance and eight normal controls were obtained from Colorado State University. They were consecutively exposed to 4 mo of a high-fiber, low-fat standard swine diet; 4 mo of a high-sucrose, high-fat, low-fiber diabetogenic diet; and 4 mo of excess diabetogenic diet for obesification. Results of oral glucose tolerance and intravenous insulin tolerance tests conducted at the end of each regimen were compared. Hyperglycemia was not observed in any animals after any manipulation. Insulin sensitivity was also not influenced by diet. We conclude that F7 low-K miniature swine from this colony fail to model human non-insulin-dependent diabetes. 相似文献
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949.
Nitrosation of amines by stimulated macrophages 总被引:10,自引:2,他引:8
Rats and mice treated in vivo with Escherichia coli lipopolysaccharide (LPS) synthesize and excrete large quantities of nitrate. Murine peritoneal macrophages, elicited in vivo with thioglycolate and stimulated in vitro with LPS and/or gamma-interferon (IFN), produce copious amounts of nitrate and nitrite. We report here experiments showing N-nitrosamine formation by macrophages immunostimulated in vitro. Macrophage cell lines J774.1, PU5-1.8, WEHI-3 and RAW 264 and freshly isolated macrophages from C3H/He mice were used. Macrophages were cultured in Dulbecco's modified Eagle's medium (pH 7.5) supplemented with calf serum (10%). Supernatant NO2- and NO3- were measured. N-Nitrosamines were extracted with dichloromethane and the extracts analyzed by a gas chromatography--thermal energy analyzer. Cells (1.5 X 10(6)/ml) were incubated with LPS (10 micrograms/ml) and morpholine (15 mM) for 72 h at 37 degrees C. Under these conditions, all of the cell types listed above produced nitrite (40-70 microM) and N-nitrosomorpholine (NMOR; 114-940 nM). LPS was required for both processes, and this effect was enhanced by IFN. Nitrite (150 microM) incubated with morpholine in cell-free medium did not form NMOR nor did cells plus morpholine and NO2-. The rate of NMOR formation in the J774.1 cell line was highest in the middle incubation period (24-36 h) although [NO2-] was highest in the final incubation period (48-72 h). Thus, the cells do not catalyze nitrosamine formation per se, rather the amine traps out a reactive nitrosating species prior to the formation of NO2- and NO3-. These results suggest that immunostimulated macrophages may be capable of nitrosamine formation under physiological conditions. 相似文献
950.
During the time period 1958-1967 190 cases of male breast cancer were reported to the Swedish Cancer Registry. The reported cases were thoroughly re-evaluated from the evidence of the clinical records and histopathologic specimens. The material contained 166 cases of histologically verified invasive breast carcinoma which were analyzed with respect to different clinical and histopathologic parameters. In contrast to the rate in females, the breast cancer incidence rate in males did not increase significantly during the period under review, and the age-specific incidence rate did not show a Clemmesen's hook but increased relatively more rapidly at high ages than for female breast carcinoma. The mean age at diagnosis was 4 to 5 years higher in male breast cancer patients than in females. Larger tumours were more frequent among older patients and there was a 5-year shift between the age-distribution curves for small (less than 2 cm) and larger (2-5 cm) tumours. A similar difference was found between pN0 and pN1 tumours. This difference might reflect the progression rate of male breast cancer. The histopathology pattern and distribution of histologic malignancy grades were similar to those in female breast carcinoma with the exception that lobular carcinoma and medullary carcinoma with lymphoid infiltration were lacking in the male material. 相似文献