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51.
Epidemiological evidence indicates that aflatoxin B1 (AFB1) intake is
associated with an increased risk of hepatocellular carcinoma (HCC). The
hepatocarcinogenesis is initiated by covalent binding of AFB1 to cellular
DNA. To determine whether nutritional factors and hormonal status may
influence the binding of AFB1 to hepatic DNA, a cross- sectional study was
performed on a total of 42 male asymptomatic hepatitis B surface antigen
(HBsAg) carriers and 43 male non-carriers in a cohort study on the
multistage development of HCC in Taiwan. The major AFB1-DNA adduct in vivo,
AFB1-N7-guanine, was measured by high- performance liquid chromatography in
urine. Urinary AFB1-N7-guanine was detectable in 40% of the subjects. HBsAg
carriers had a higher detection rate of urinary AFB1-DNA adducts than
non-carriers and the difference was statistically significant after
multivariate adjustment. After taking into account the total AFB1 urinary
metabolite level, chronic HBsAg carrier status, and other potential
confounders, plasma levels of cholesterol, alpha-tocopherol, and alpha- and
beta-carotene were positively associated with the detection rate of the
AFB1-DNA adducts in a dose-dependent manner, whereas plasma lycopene level
was inversely related to the presence of the adducts in urine. The
association of urinary AFB1-DNA adducts with the plasma levels of
cholesterol, alpha-tocopherol, lycopene, and alpha- and beta-carotene was
observed at both low and high exposure levels of AFB1. There was a
synergistic interaction of plasma alpha-tocopherol with alpha- and beta-
carotene on the adduct levels. No association with the adducts was found
for plasma levels of retinol and testosterone. This study demonstrated
different associations of antioxidant vitamins with AFB1- DNA adduct
formation. The data consistent with our previous finding in cultured
woodchuck hepatocytes that alpha-tocopherol and beta-carotene enhanced
AFB1-DNA adduct formation suggest that prospective investigation of the
relationship between plasma micronutrients and risk of AFB1-related HCC is
warranted.
相似文献
52.
The dose of glucocorticoid was evaluated in the treatment of 19 patients with salt-losing congenital adrenal hyperplasia due to complete or nearly complete 21-hydroxylase deficiency. In most cases, follow-up was from infancy to puberty. The dose of steroid was expressed as oral cortisol (mg/m2 body surface area 124 hours); the equivalent doses of the various glucocorticoid preparations was as follows: 100 mg oral cortisol = 120 mg oral cortisone acetate = 25 mg oral prednisone = 50 mg intramuscular cortisol = 60 mg intramuscular cortisone acetate. The dose of glucocorticoid producing good laboratory and clinical control varied significantly with age. The dose fell from 26 mg/m2 /24 hours in early infancy to 19 mg/m2 /24 hours between 6 and 8 years of age, and then rose to 23–24 mglm2 /hour in adolescence. In addition to these age-related changes, there were large individual variations at each age. Indeed, the values from 4 of the 19 patients were not included in the calculation of the mean because they were more than 3 SD either above or below the mean. For the rest of the patients, the coefficient of variation ranged from 14.5% to 37.2%. It is concluded that glucocorticoid therapy must be adjusted carefully to the age and needs of each patient. 相似文献
53.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored. 相似文献
54.
55.
Sickle cell disease: imaging of cerebrovascular complications 总被引:3,自引:0,他引:3
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59.
Prevalence of conditions potentially associated with lower urinary tract symptoms in men 总被引:2,自引:0,他引:2
Gades NM Jacobson DJ Girman CJ Roberts RO Lieber MM Jacobsen SJ 《BJU international》2005,95(4):549-553
OBJECTIVE: To estimate the frequency of conditions associated with lower urinary tract symptoms (LUTS, typically included when assessing benign prostatic hyperplasia, BPH), as other causes of LUTS should be excluded when diagnosing BPH, using data from the Olmsted County Study of Urinary Symptoms and Health Status among Men. SUBJECTS AND METHODS: During 1989-91, Caucasian men aged 40-79 years were randomly selected from the Olmsted County population. Before contact, eligibility was determined by reviewing the community medical records. Baseline exclusion criteria included comorbid pre-existing conditions or treatments, e.g. prostate, bladder or lower back surgery, bladder neck contracture or cancer, diabetes with lower extremity amputation, and neurological diseases, including Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, tabes dorsalis and stroke. Men with these conditions were excluded from the Olmsted County Study at baseline, because these conditions are potentially associated with LUTS. RESULTS: Of the 5100 randomly sampled men, 13.4% met at least one of the pre-existing exclusion criteria. Individually, the frequency of exclusions was 7.8% for prostate cancer or surgery, 4.8% for back surgery, 1.3% for bladder surgery and 1.4% for neurological conditions. All other conditions represented <1.0% of the study exclusions. Older men were more likely to meet at least one of the exclusion criteria, with men in their fifth to eighth decade having a total exclusion frequency of 1.4%, 5.4%, 8.5% and 32.8%, respectively. The most common reason for men in their fifth decade to be excluded was lower back surgery (0.9%), whereas the most common reason in the eighth was prostate surgery (21.8%). CONCLUSIONS: In men, conditions that may contribute to LUTS, other than BPH, are prevalent in the community and increase in frequency with age. It is important that other conditions associated with LUTS be excluded before a definitive diagnosis of BPH. Any oversight in this initial evaluation can potentially result in misclassification bias, misdiagnosis and incorrect treatment of patients. 相似文献
60.
Pischon T Girman CJ Rifai N Hotamisligil GS Rimm EB 《The American journal of clinical nutrition》2005,81(4):780-786
BACKGROUND: Adiponectin, an adipocyte-derived peptide, improves insulin sensitivity, has antiinflammatory and antiatherogenic effects, and is associated with a lower risk of ischemic heart disease (IHD) and type 2 diabetes. However, little is known about dietary predictors of plasma adiponectin concentrations in humans. OBJECTIVE: Our objective was to examine cross-sectionally the association between dietary factors and plasma adiponectin in men. DESIGN: Our study included 532 male participants of the Health Professionals Follow-Up Study who were selected as control subjects for an investigation of biological predictors of IHD. Diet, lifestyle, and anthropometric data were assessed by questionnaires. RESULTS: After multivariable adjustment, adiponectin was significantly inversely related to glycemic load (-1.3 mg/L per 1-SD increase; P = 0.02) and tended to be positively associated with total fat intake (0.7 mg/L per 0.5% of energy from fat instead of carbohydrates; P = 0.06). We also found a significant nonlinear association between plasma adiponectin concentrations and alcohol intake (P for quadratic trend = 0.01). Thus, whereas nondrinkers had mean plasma adiponectin concentrations of 16.48 mg/L, those who consumed 0.1-4.9, 5.0-14.9, 15.0-29.9, or >/=30 g alcohol/d had mean concentrations of 16.79 (P = 0.77 compared with nondrinkers), 18.97 (P = 0.02), 19.11 (P = 0.01), and 18.39 (P = 0.10) mg/L, respectively. CONCLUSIONS: Moderate alcohol intake is associated with higher adiponectin concentrations, whereas a carbohydrate-rich diet with a high glycemic load is associated with lower adiponectin concentrations in men with no history of cardiovascular disease. Although the strength of these associations was modest, our observations highlight the hypothesis that dietary factors may modulate plasma adiponectin concentrations-a potential mediator related to a reduced IHD risk. 相似文献