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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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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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OBJECTIVE: This study examined whether dementia patients with greater cognitive reserve had increased mortality rates, and whether this association was different across strata of cognition, functional ability and depression. METHODS: In the community-based Amsterdam Study of the Elderly, 261 non-institutionalized dementia patients, identified using the Geriatric Mental State Schedule (GMS), were followed for an average of 55.5 months after which mortality data were obtained. Cognitive reserve was indicated by years of education and pre-morbid intelligence (measured using the Dutch Adult Reading Test). Cognition, functional ability and depression were indicated by Mini-Mental State scores, ADL and IADL measurements and GMS depressive syndrome, respectively. RESULTS: During the follow-up 146 persons (55.9%) died. Cox regression analyses showed that more highly educated dementia patients had higher mortality rates, only if they had low MMSE scores or if they had a concurrent depression. Pre-morbid intelligence was associated with a higher mortality rate, independent of cognition, but this association was much stronger among patients with depression. The positive association between education or intelligence and mortality was not modified by functional disabilities. CONCLUSIONS: The results suggest that dementia patients with greater cognitive reserve have increased mortality rates, only if the disease has progressed to such an extent that clinical symptoms are more severe. In this respect, the reserve hypothesis needs a modification. Depression in dementia patients with greater cognitive reserve may reflect a subgroup of patients with poor prognosis.  相似文献   
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The integrity of sperm DNA is crucial for the maintenance of genetic health. A major source of damage is reactive oxygen species (ROS) generation; therefore, antioxidants may afford protection to sperm DNA. The objectives of the study were, first, to measure the effects of antioxidant supplementation in vitro on endogenous DNA damage in spermatozoa using the single cell gel electrophoresis (comet) assay and, second, to assess the effect of antioxidant supplementation given prior to X-ray irradiation on induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll centrifugation in the presence of ascorbic acid (300, 600 microM), alpha tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5, 10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand breakage was measured using the comet assay. Sperm DNA was protected from DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60 microM) and urate (400 microM). These antioxidants provided protection from subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or ascorbate and alpha tocopherol together induced further DNA damage. Supplementation in vitro with the antioxidants ascorbate, urate and alpha tocopherol separately has beneficial effects for sperm DNA integrity.   相似文献   
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