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21.
Epidemiological data show that reproductive and hormonal factors are involved in the etiology of endometrial cancer, but there is little data on the association with endogenous sex hormone levels. We analyzed the association between prediagnostic serum concentrations of sex steroids and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition using a nested case-control design of 247 incident endometrial cancer cases and 481 controls, matched on center, menopausal status, age, variables relating to blood collection, and, for premenopausal women, phase of menstrual cycle. Using conditional regression analysis, endometrial cancer risk among postmenopausal women was positively associated with increasing levels of total testosterone, free testosterone, estrone, total estradiol, and free estradiol. The odds ratios (ORs) for the highest versus lowest tertile were 2.66 (95% confidence interval (CI) 1.50-4.72; P=0.002 for a continuous linear trend) for estrone, 2.07 (95% CI 1.20-3.60; P=0.001) for estradiol, and 1.66 (95% CI 0.98-2.82; P=0.001) for free estradiol. For total and free testosterone, ORs for the highest versus lowest tertile were 1.44 (95% CI 0.88-2.36; P=0.05) and 2.05 (95% CI 1.23-3.42; P=0.005) respectively. Androstenedione and dehydroepiandrosterone sulfate were not associated with risk. Sex hormone-binding globulin was significantly inversely associated with risk (OR for the highest versus lowest tertile was 0.57, 95% CI 0.34-0.95; P=0.004). In premenopausal women, serum sex hormone concentrations were not clearly associated with endometrial cancer risk, but numbers were too small to draw firm conclusions. In conclusion, relatively high blood concentrations of estrogens and free testosterone are associated with an increased endometrial cancer risk in postmenopausal women.  相似文献   
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Alzheimer Disease, characterised by a global impairment of cognitive functions, is more and more common in Western societies, both because of longer life expectancy and, probably, because of increasing incidence. Several hints suggest that this degenerative disease is linked to western diet, characterised by excessive dietary intake of sugar, refined carbohydrates (with high glycaemic index), and animal product (with high content of saturated fats), and decreased intake of unrefined seeds--cereals, legumes, and oleaginous seeds--and other vegetables (with high content of fibres, vitamins, polyphenols and other antioxidant substances, phytoestrogens) and, in several populations, of sea food (rich in n-3 fatty acids). It has been hypothesised, in fact, that AD, may be promoted by insulin resistance, decreased endothelial production of nitric oxide, free radical excess, inflammatory metabolites, homocysteine, and oestrogen deficiency. AD, therefore, could theoretically be prevented (or delayed) by relatively simple dietary measures aimed at increasing insulin sensitivity (trough reduction of refined sugars and saturated fats from meat and dairy products), the ratio between n-3 and n-6 fatty acids (e.g. from fish and respectively seed oils), antioxidant vitamins, folic acid, vitamin B6, phytoestrogens (vegetables, whole cereals, and legumes, including soy products), vitamin B12 (bivalve molluscs, liver), and Cr, K, Mg, and Si salts. This comprehensive improvement of diet would fit with all the mechanistic hypotheses cited above. Several studies, on the contrary, are presently exploring monofactorial preventive strategies with specific vitamin supplementation or hormonal drugs, without, however, appreciable results.  相似文献   
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The incidence of ovarian cancer is up to 10 times higher in Western countries than in rural Asia and Africa. One common consequence of a Western lifestyle is the development of excessive body weight and obesity. A multi‐centre prospective study was conducted to investigate the association between body mass index (BMI) and ovarian cancer risk. A case‐control study was nested within 3 prospective cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). Information on anthropometry, demographic characteristics, medical history and lifestyle was obtained at the time of subjects' recruitment in each cohort. Women diagnosed with primary, invasive epithelial ovarian cancer from the 3 cohorts (n = 122) diagnosed 12 months or later after recruitment into the respective cohort served as case subjects. For each case subject, 2 control subjects that matched the case subject on cohort, menopausal status, age and date of recruitment were randomly identified. Data were analyzed by conditional logistic regression. There was an inverse association between BMI and ovarian cancer risk. For increasing quartiles of BMI above the lowest, the ORs were 0.62 (0.32–1.21), 0.59 (0.30–1.17) and 0.46 (0.23–0.92), p = 0.03. Analyses limited to women diagnosed 3 or more years after recruitment into the cohorts did not alter these findings. When obese women (BMI > 30) were compared to lean women (BMI ≤ 23), the inverse association became stronger, with an OR of 0.38 (0.17–0.85), p < 0.02. There was some evidence of direct association of ovarian cancer with height, which was limited to cancers diagnosed before age 55. Our data suggest that increasing body weight may confer a protection against ovarian cancer. © 2002 Wiley‐Liss, Inc.  相似文献   
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Cancer prevalence in European registry areas.   总被引:3,自引:0,他引:3  
BACKGROUND: Information on cancer prevalence is of major importance for health planning and resource allocation. However, systematic information on cancer prevalence is largely unavailable. MATERIALS AND METHODS: Thirty-eight population-based cancer registries from 17 European countries, participating in EUROPREVAL, provided data on almost 3 million cancer patients diagnosed from 1970 to 1992. Standardised data collection and validation procedures were used and the whole data set was analysed using proven methodology. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as of melanoma of skin, Hodgkin's disease, leukaemia and all malignant neoplasms combined, were estimated for the end of 1992. RESULTS: There were large differences between countries in the prevalence of all cancers combined; estimates ranged from 1170 per 100000 in the Polish cancer registration areas to 3050 per 100000 in southern Sweden. For most cancers, the Swedish, Swiss, German and Italian areas had high prevalence, and the Polish, Estonian, Slovakian and Slovenian areas had low prevalence. Of the total prevalent cases, 61% were women and 57% were 65 years of age or older. Cases diagnosed within 2 years of the reference date formed 22% of all prevalent cases. Breast cancer accounted for 34% of all prevalent cancers in females and colorectal cancer for 15% in males. Prevalence tended to be high where cancer incidence was high, but the prevalence was highest in countries where survival was also high. Prevalence was low where general mortality was high (correlation between general mortality and the prevalence of all cancers = -0.64) and high where gross domestic product was high (correlation = +0.79). Thus, the richer areas of Europe had higher prevalence, suggesting that prevalence will increase with economic development. CONCLUSIONS: EUROPREVAL is the largest project on prevalence conducted to date. It has provided complete and accurate estimates of cancer prevalence in Europe, constituting essential information for cancer management. The expected increases in prevalence with economic development will require more resources; allocation to primary prevention should therefore be prioritised.  相似文献   
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Toward a comparison of survival in American and European cancer patients   总被引:11,自引:0,他引:11  
BACKGROUND: Only recently have extensive population-based cancer survival data become available in Europe, providing an opportunity to compare survival in Europe and the United States. METHODS: The authors considered 12 cancers: lung, breast, stomach, colon, rectum, melanoma, cervix uteri, corpus uteri, ovary, prostate, Hodgkin disease, and non-Hodgkin lymphoma. The authors analyzed 738,076 European and 282,398 U.S. patients, whose disease was diagnosed in 1985-1989, obtained from 41 EUROCARE cancer registries in 17 countries and 9 U.S. SEER registries. Relative survival was estimated to correct for competing causes of mortality. RESULTS: Europeans had significantly lower survival rates than U.S. patients for most cancers. Differences in 5-year relative survival rates were higher for prostate (56% vs. 81%), skin melanoma (76% vs. 86%), colon (47% vs. 60%), rectum (43% vs. 57%), breast (73% vs. 82%), and corpus uteri (73% vs. 83%). Survival declined with increasing age at diagnosis for most cancers in both the U.S. and Europe but was more marked in Europe. CONCLUSIONS: Survival for most major cancers was worse in Europe than the U.S. especially for older patients. Differences in data collection, analysis, and quality apparently had only marginal influences on survival rate differences. Further research is required to clarify the reasons for the survival rate differences.  相似文献   
27.
Data from a hospital based case-control study of lung cancer in Western Europe were used to examine changes in the risk of developing lung cancer after changes in habits of cigarette smoking. Only data for subjects who had smoked regularly at some time in their lives were included. The large size of the study population (7181 patients and 11 006 controls) permitted precise estimates of the effect of giving up smoking. Risks of developing lung cancer for people who had given up smoking 10 or more years before interview were less than half of those for people who continued to smoke. The reduction in risk was seen in men and women and in former smokers of both filter and non-filter cigarettes but varied by duration of smoking habit before giving up. The protective effect of giving up became progressively greater with shorter duration of smoking habit. The risks after not smoking for 10 years for both men and women who had previously smoked for less than 20 years were roughly the same as those for lifelong non-smokers. Reducing the number of cigarettes smoked a day or switching from non-filter to filter cigarettes also lowered the risk of developing lung cancer but not to the extent associated with giving up smoking.  相似文献   
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Background. State entropy (SE) is a newly available monitorfor depth of anaesthesia. We investigated whether the relationshipbetween predicted effect-site propofol concentration and bothbispectral index (BIS) and SE values is useful for predictingloss of verbal contact and loss of consciousness during steady-stateconditions. Methods. Twenty unpremedicated patients undergoing electivemajor abdominal surgery were recruited. A target-controlledinfusion of propofol was administered using Schneider's pharmacokineticmodel. The propofol infusion was set at an initial site-effectconcentration of 1.0 µg ml–1, and increased by 1.0µg ml–1 steps every 4 min, up to 6.0 µg ml–1.A 4-min interval was chosen to ensure that steady-state site-effectconcentrations were obtained. Propofol site-effect concentrationsand BIS and SE values were recorded at loss of verbal contact(LVC) and loss of consciousness (LOC). Population values forpredicted effect-site concentrations at the clinical endpointswere estimated and correlated with BIS and SE values. Results. For LVC, the effect-site concentration for 90% of patientswas 1.1 (1.1–3.2) µg ml–1 and for LOC 2.8(2.8–5.65) µg ml–1. LVC occurred in 90% ofpatients at a BIS value of 70.2 (70.2–90.2) and an SEvalue of 60.3 (60.3–75.5) and LOC occurred at a BIS valueof 38.2 (38.2–70.4) and an SE value of 42.2 (42.2–60.4). Conclusions. LVC and LOC occurred within a defined range ofpredicted effect-site concentrations. SE had a smaller rangethan BIS and higher correlation with effect-site concentrationand may be more useful than BIS in predicting both LVC and LOC.  相似文献   
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