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41.
42.
Body mass index and colon cancer mortality in a large prospective study 总被引:10,自引:0,他引:10
Murphy TK Calle EE Rodriguez C Kahn HS Thun MJ 《American journal of epidemiology》2000,152(9):847-854
Obesity has been reported to increase the risk of colon cancer, especially in men. The authors examined this relation in the American Cancer Society's Cancer Prevention Study II, a nationwide mortality study of US adults. After 12 years of follow-up, 1,616 deaths from colon cancer in women and 1,792 in men were observed among 496,239 women and 379,167 men who were cancer free at enrollment in 1982. The authors used Cox proportional hazards analyses to control for effects of age, race, education, smoking, exercise, alcohol, parental history of colon cancer, fat intake, vegetable and grain intake, aspirin use and, in women, estrogen replacement therapy. In men, death rates from colon cancer increased across the entire range of body mass index (BMI). The rate ratio was highest for men with BMI > or =32.5 (rate ratio (RR) = 1.90, 95% confidence interval (CI): 1.46, 2.47) compared with men with BMI between 22.00 and 23.49. In women, a weaker association was seen in the three BMI categories of 27.5-29.9 (RR = 1.26, 95% CI: 1.03, 1.53), 30.0-32.4 (RR = 1.37, 95% CI: 1.09, 1.72), and > or =32.5 (RR = 1.23, 95% CI: 0.96, 1.59). These prospective data support the hypothesis that obesity increases the risk of colon cancer death and that the relation is stronger and more linear in men than in women. 相似文献
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Ultraviolet-light induced p53 mutational spectrum in yeast is indistinguishable from p53 mutations in human skin cancer 总被引:1,自引:2,他引:1
Inga A; Scott G; Monti P; Aprile A; Abbondandolo A; Burns PA; Fronza G 《Carcinogenesis》1998,19(5):741-746
Ultraviolet (UV) light has been associated with the development of human
non-melanoma skin cancers (NMSC). Such cancers often exhibit mutations in
the p53 tumour suppressor gene. In order to determine the UV-induced p53
mutation spectrum, a yeast expression vector that harbours a human
wild-type p53 cDNA was UV-irradiated in vitro and transfected into a yeast
strain that contained the ADE2 gene regulated by a p53-responsive promoter.
Forty-five mutant clones contained 51 mutations. Seven mutations were
tandem base pair substitutions, four of which being CC-->TT, hallmark
mutations of UV mutagenesis. Eighty percent (41/51) of the mutations were
single or non-tandem base pair substitutions, the majority of which (27/41)
were C-->T transitions. Ninety-five percent of such mutations occurred
at dipyrimidine sites. Through a rigorous statistical test, the UV-induced
p53 mutation spectrum appears to differ significantly (P < 0.008) from
the one induced by the antineoplastic drug
chloroethyl-cyclohexyl-nitrosourea, and to be indistinguishable from the
one observed in NMSC (P = 0.4). These results demonstrate that the assay
allows the determination of carcinogen-specific p53 mutation fingerprints
and represents a new tool for molecular epidemiology.
相似文献
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Enrique Teran Carlos Escudero Sandra Vivero Armando Enriquez Andres Calle 《Hypertension in pregnancy》2004,23(3):303-308
OBJECTIVE: To investigate the intraplatelet cyclic guanosine-3',5'-monophosphate (cGMP) levels during normal pregnancy and preeclampsia. STUDY DESIGN: Pregnant women (n = 15), women with preeclampsia (n = 15), and nonpregnant, normotensive women (n = 15) were included. Intraplatelet cyclic guanosine-3',5'-monophosphate levels were measured by an enzyme-linked immunosorbent assay. RESULTS: Intraplatelet cGMP levels were significantly different among all groups (p < 0.02). The values were higher in normal pregnant women (mean 19.8 SD 2.6 fmol/10(5) platelets) in comparison to nonpregnant women (mean 7.6 SD 0.3 fmol/10(5)platelets; p = 0.001) and women with preeclampsia (mean 11.3 SD 1.8 fmol/10(5) platelets; p = 0.05). Plasma nitric oxide levels did not reveal differences between all groups. CONCLUSIONS: The results of this study in a high-risk Andean population demonstrated that intraplatelet cyclic guanosine-3',5'-monophosphate levels are decreased during preeclampsia compared to normal pregnancy, suggesting a lack in action of nitric oxide. 相似文献
47.
Alpa V Patel Carmen Rodriguez Leslie Bernstein Ann Chao Michael J Thun Eugenia E Calle 《Cancer epidemiology, biomarkers & prevention》2005,14(2):459-466
BACKGROUND: Obesity and physical activity, in part through their effects on insulin sensitivity, may be modifiable risk factors for pancreatic cancer. METHODS: The authors analyzed data from the American Cancer Society Cancer Prevention Study II Nutrition Cohort to examine the association between measures of adiposity, recreational physical activity, and pancreatic cancer risk. Information on current weight and weight at age 18, location of weight gain, and recreational physical activity were obtained at baseline in 1992 via a self-administered questionnaire for 145,627 men and women who were cancer-free at enrollment. During the 7 years of follow-up, 242 incident pancreatic cancer cases were identified among these participants. Cox proportional hazards modeling was used to compute hazard rate ratios (RR) and to adjust for potential confounding factors including personal history of diabetes and smoking. RESULTS: We observed an increased risk of pancreatic cancer among obese [body mass index (BMI) >/= 30] men and women compared with men and women of normal BMI [<25; RR, 2.08; 95% confidence interval (95% CI), 1.48-2.93, P(trend) = 0.0001]. After adjustment for between BMI, risk of pancreatic cancer was independently increased among men and women who reported a tendency for central weight gain compared with men and women reporting a tendency for peripheral weight gain (RR, 1.45; 95% CI, 1.02-2.07). We observed no difference in pancreatic cancer incidence rates between men and women who were most active (>31.5 metabolic equivalent hours per week) at baseline compared with men and women who reported no recreational physical activity (RR, 1.20; 95% CI, 0.63-2.27). CONCLUSION: This study, along with several recent studies, supports the hypothesis that obesity and central adiposity are associated with pancreatic cancer risk. 相似文献
48.
Maxine Loh Webster F. Vital Vinh Vu Ronald Navarrete Paola Calle Virginia R. Shervette Antonio Torres Windsor E. Aguirre 《Conservation Genetics Resources》2014,6(1):229-231
Sixteen polymorphic, dinucleotide microsatellite loci were developed for Rhoadsia altipinna, a small characid fish from impacted rivers in south western Ecuador. None of the loci were in linkage disequilibrium or deviated significantly from Hardy–Weinberg equilibrium after sequential Bonferroni correction. Variability was relatively high with allelic richness ranging between 2 and 22 alleles per locus (average = 9.125), observed heterozygosity ranging between 0.125 and 0.958 (average = 0.695), and expected heterozygosity ranging between 0.120 and 0.952 (average = 0.736). 相似文献
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50.
Comparison of Bilateral vs. Staged Unilateral Deep Brain Stimulation (DBS) in Parkinson's Disease in Patients Under 70 Years of Age
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