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The authors studied the association between heart disease and prostatic cancer in Rancho Bernardo, California, from August 1972 to June 1987. During a 14-year follow-up of 1,776 men aged 50-84 years, 100 cases of prostatic cancer were identified, of which 54 were incident. Systolic blood pressure, cigarette smoking, and plasma cholesterol levels in cases did not differ from those in noncases. After adjustment for age and on multivariate analysis, incident cases of prostatic cancer had a nonsignificantly higher frequency of reported heart disease at baseline. History of diabetes was inversely associated with total prostatic cancer (age-adjusted estimated relative risk = 0.2, 90% confidence interval: 0.0-0.8; multivariate-adjusted relative risk = 0.3, 90% confidence interval: 0.1-1.0). The association between heart disease and prostatic cancer is compatible with diagnostic detection bias. The inverse association between diabetes and prostatic cancer is compatible with a cancer-promoting role for endogenous testosterone, the level of which is lower in diabetics, or a risk-reducing effect of antidiabetic diet or drug therapy.  相似文献   
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Dietary phytoestrogens are suggested to reduce the risk of prostate and colorectal cancer, but the results of epidemiologic studies have not yielded consistent support for this proposed effect, possibly due to inadequate databases of phytoestrogen levels in foods. Biomarkers of phytoestrogen intakes may provide a clearer insight into the relationship between phytoestrogen exposure and the risk of prostate or colorectal cancer risks. From the European Prospective into Cancer-Norfolk cohort (ages 45-75), serum and urine samples were analyzed for seven phytoestrogens [daidzein, enterodiol, enterolactone, genistein, glycitein, O-desmethylangolensin (O-DMA), and equol] among 193 cases of prostate cancer and 828 controls, and 221 cases of colorectal cancer with 889 controls. Summary variables of total lignans (enterodiol and enterolactone) and total isoflavones (daidzein, genistein, O-DMA, equol, and glycitein) were created and analyzed in conjunction with individual phytoestrogens. Logistic regression analyses revealed that there was no significant association between prostate cancer risk and total serum isoflavones [odds ratio (OR), 1.01; 95% confidence interval (CI), 0.93-1.10] or total serum lignans (OR, 0.94; 95% CI, 0.86-1.04) or between colorectal cancer risk and total serum isoflavones (OR, 1.01; 95% CI, 0.94-1.08) or total serum lignans (OR, 1.03; 95% CI, 0.94-1.12). Similarly, null associations were observed for individual serum phytoestrogens and for all urinary phytoestrogen biomarkers. In conclusion, we have found no evidence to support an inverse association between phytoestrogen exposure and prostate or colorectal cancer risk.  相似文献   
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BACKGROUND: Plasma fibrinogen may be an independent risk factor for cardiovascular disease. Cigarette smoking is a well-recognized determinant of plasma fibrinogen however it remains unclear how fibrinogen levels relate to the degree and duration of smoking, or to time since smoking cessation. METHODS: In a population-based study of 11 059 men and women aged 45-74 years, we examined the cross-sectional relationship between plasma fibrinogen and cigarette smoking habit. RESULTS: Mean fibrinogen concentrations were higher in current smokers compared to non-current smokers (men: 3.13+/-0.77 versus 2.80+/-0.71 g/l, P<0.0001; women: 3.03+/-0.72 versus 2.95+/-0.71 g/l, P=0.01), independent of age, body mass index and hormone replacement therapy in women In men, fibrinogen concentrations declined with years since stopping smoking but remained higher than in life-long non-smokers for 15 years. No relationship between fibrinogen and duration of smoking cessation was observed in women. On multivariate analysis, age, body mass index, use of hormone-replacement therapy, smoking status and pack-years of smoking were independent predictors of plasma fibrinogen. CONCLUSIONS: Plasma fibrinogen is strongly associated with cigarette smoking with a dose-response relationship with total pack-years of smoking. In men who stop smoking plasma fibrinogen may remain elevated for several years after cessation.  相似文献   
88.
A sensitive enzyme linked immunosorbent assay (ELISA) was developed to evaluate the potential of herpes simplex virus (HSV) specific antibodies in the diagnosis of herpetic eye infection. The presence of HSV specific secretory IgA (sIgA) in tears was found to be diagnostic of infection. However, serum and tear HSV specific IgG and IgA were not considered reliable indicators of active infection.  相似文献   
89.
Ultrasonic patterns in inflammatory bowel disease.   总被引:1,自引:0,他引:1  
Ultrasound examination was performed in 90 patients with varying bowel pathology. Ultrasound reliably demonstrated thickening of the bowel. In addition, the pattern of abnormality seen in Crohn's disease and ulcerative colitis was different, and corresponded to the pathological changes seen in these disease processes. The pattern of bowel abnormality seen in other bowel diseases with an inflammatory aetiology generally corresponded to either the Crohn's or ulcerative colitic pattern. The appearances are described, together with findings in other non-neoplastic diseases of the bowel.  相似文献   
90.
The ability to diagnose and localize vascular graft infections has been a major challenge. Recent studies in animal models and humans with focal bacterial infection have shown that radiolabeled, polyclonal, human immunoglobulin G accumulates at the site of inflammation and can serve as the basis for an imaging technique. This study investigated this new technique for the diagnosis and localization of vascular graft infections. Twenty-five patients with suspected vascular infections involving grafts (22), atherosclerotic aneurysms (2), and subclavian vein thrombophlebitis (1) were studied. Gamma camera images of the suspected area were obtained between 5 and 48 hours after intravenous administration of 1.5 to 2.0 mCi (56 to 74 mBq) of indium 111-labeled, human, polyclonal immunoglobulin G. Scan results were interpreted without clinical information about the patient and were subsequently correlated with surgical findings, other imaging modalities, and/or clinical follow-up. In 10 of 10 patients found to have positive scan results, localized infections were confirmed at the involved sites. In 14 of 15 patients whose scan results were interpreted as negative, no vascular infections were identified at follow-up. The patient with false-negative results and recurrent bacteremia from an aortoduodenal fistula was found to have a negative scan outcome at a time when his disease was quiescent. These data suggest that nonspecific, human, indium 111-labeled immunoglobulin G scanning can be a useful noninvasive means of localizing vascular infections.  相似文献   
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