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991.
Summary We studied the association between osteoporotic fractures and prior non-melanoma skin cancer (NMSC, a biomarker for cumulative sun exposure). The risk of prior NMSC in our fracture cohort was significantly reduced (standardised incidence ratio 0.69, 95% CI 0.61, 0.78). Adequate lifetime sun exposure may be necessary to protect against osteoporotic fractures in later life. Introduction The relationship between cumulative sun exposure and osteoporotic fractures is uncertain. We aimed to study the association between non-melanoma skin cancer (NMSC), a marker of cumulative sun exposure, and osteoporotic fractures in an older cohort. Methods A retrospective cohort study in southern Tasmania in people aged at least 50 years with incident radiographic fracture (n = 2,283) was carried out. By record linkage to the Tasmanian Cancer Registry the cohort was followed backwards through time until the occurrence of NMSC or end-of follow-up. Relative risk was estimated by the standardised incidence ratio (SIR) using sex-, age- and calendar year-specific cancer incidence rates in southern Tasmania as reference. Results The incidence of prior NMSC in the fracture cohort was 31% lower than for the general population (SIR 0.69, 95% CI 0.61, 0.78). This effect was significant for most fracture subtypes except pelvic and wrist fractures and observed for both NMSC subtypes, squamous cell carcinoma and basal cell carcinoma. Conclusions Older people with osteoporotic fractures may have had lifestyles linked to lower cumulative sunlight exposure. Achieving a balance between adequate lifetime sun exposure and protection against its adverse effects (such as fractures and skin cancer) may require assessment of individual risks.  相似文献   
992.
BACKGROUND: Acute renal failure (ARF) is a frequent complication of coronary artery bypass grafting (CABG) surgery and is strongly associated with perioperative morbidity and mortality. We hypothesized that renal artery stenosis (RAS), causing occult renal ischemia, may be an important factor contributing to development of ARF after CABG surgery. METHODS: Preoperative and intraoperative data on 798 consecutive adult patients undergoing CABG surgery with cardiopulmonary bypass from February 1, 1995 to February 1, 1997 (who had also undergone an abdominal aortogram for the evaluation of RAS) were recorded and entered into a computerized database. The development of ARF was defined as a rise in serum creatinine of 1 mg/dL (88.4 micromol/L) above baseline postoperatively. The association between the presence of renal artery stenosis together with preoperative and intraoperative variables and the development of ARF was assessed by multivariate logistic regression. RESULTS: A total of 798 patients underwent isolated coronary bypass grafting, of which 18.7% demonstrated 50% or more RAS. ARF developed in 82 patients (10.2%), of which three (0.3%) required dialysis support. The mortality for patients who developed ARF was 14% (OR 15, P=0.0001) compared to 0.2% among those who did not develop ARF. The presence of renal artery stenosis of any severity ranging from unilateral 50% RAS to bilateral 95% RAS was not associated with the subsequent development of ARF. CONCLUSIONS: The development of ARF following CABG surgery is associated with high mortality. The presence of RAS does not appear to increase the risk for developing ARF.  相似文献   
993.
BACKGROUND: For many years it has been assumed that the risk of childhood respiratory allergies is related to allergen exposures in early life. There are, however, few prospective data in support. We aimed to examine this relationship in a representative cohort of children born in Ashford, Kent (UK). METHODS: 625 children (94% of those eligible) were followed from birth to the age of 5.5 years at which time 552 underwent skin prick testing to extracts of house dust mite and cat fur allergens. Maternal reports of wheeze in the last year were collected by interview. These outcomes were related to individual domestic concentrations of Der p 1 and Fel d I allergens estimated from dust collection at the age of 8 weeks. RESULTS: 10% of children were sensitised to house dust mite or cat at age 5.5 years; 7% had atopic wheeze. No significant relationships between allergen exposure and either sensitisation or wheeze were found but, on examination, the exposure-response relationships for both allergens and for each outcome rose steeply at low levels of exposure and were attenuated at high levels of exposure. These patterns were modified by paternal atopy and by birth order. CONCLUSIONS: There are no linear relationships between early allergen exposure and the induction of childhood respiratory allergy; rather, the risks of IgE sensitisation and asthma rise at very low levels of exposure and are attenuated thereafter. These patterns are influenced by parental atopy and birth order. These findings suggest important gene-environment interactions in the development of atopy and asthma and imply that reductions in domestic allergen exposure alone are unlikely to have a major impact in decreasing the incidence of these diseases in childhood.  相似文献   
994.
EPA and DHA, long-chain (n-3) PUFA largely obtained from fish, inhibit the proliferation of breast cancer cells in vitro and reduce the initiation and progression of breast tumors in laboratory animals. Our purpose in this analysis was to examine whether intake of these marine fatty acids (EPA and DHA) were associated with prognosis in a cohort of women who had been diagnosed and treated for early stage breast cancer (n = 3,081). Median follow-up was 7.3 y. Dietary intake was assessed using 24-h recalls (~4 recalls per dietary assessment obtained at 7 time points over 6 y). Survival models with time-dependent covariates were used to examine the association of repeated measures of dietary intake of EPA and DHA from food (i.e., marine sources) and supplements with disease-free survival and overall survival. Women with higher intakes of EPA and DHA from food had an approximate 25% reduced risk of additional breast cancer events [tertile 2: HR = 0.74 (95% CI = 0.58-0.94); tertile 3: HR = 0.72 (95% CI = 0.57-0.90)] compared with the lowest tertile of intake. Women with higher intakes of EPA and DHA from food had a dose-dependent reduced risk of all-cause mortality [tertile 2: HR = 0.75 (95% CI = 0.55-1.04); tertile 3: HR = 0.59 (95% CI = 0.43-0.82)]. EPA and DHA intake from fish oil supplements was not associated with breast cancer outcomes. The investigation indicates that marine fatty acids from food are associated with reduced risk of additional breast cancer events and all-cause mortality.  相似文献   
995.
996.
In Hong Kong, methadone maintenance treatment (MMT) was launched in the 1970s, almost 30 years before the counterpart programme’s inauguration in Mainland China. Both were established in response to perceived public crises—addiction-related crime and HIV outbreak, respectively—and both are now regular services under two systems in the same country. Effectiveness of MMT in achieving the stated goals was evident in each case and provides useful lessons on strategies for dealing with the varied concerns related to illicit drug use. Today, with changing patterns of drug addiction, increasing competition for resources, and changing attitudes towards addiction and its treatment, the two MMT systems are confronted with similar challenges to achieve sustainability.  相似文献   
997.
Nutritional ketosis is a state of mildly elevated blood ketone concentrations resulting from dietary changes (e.g., fasting or reduced carbohydrate intake) or exogenous ketone consumption. In this study, we determined the tolerability and safety of a novel exogenous ketone diester, bis-hexanoyl-(R)-1,3-butanediol (BH-BD), in a 28-day, randomized, double-blind, placebo-controlled, parallel trial (NCT04707989). Healthy adults (n = 59, mean (SD), age: 42.8 (13.4) y, body mass index: 27.8 (3.9) kg/m2) were randomized to consume a beverage containing 12.5 g (Days 0–7) and 25 g (Days 7–28) of BH-BD or a taste-matched placebo daily with breakfast. Tolerability, stimulation, and sedation were assessed daily by standardized questionnaires, and blood and urine samples were collected at Days 0, 7, 14, and 28 for safety assessment. There were no differences in at-home composite systemic and gastrointestinal tolerability scores between BH-BD and placebo at any time in the study, or in acute tolerability measured 1-h post-consumption in-clinic. Weekly at-home composite tolerability scores did not change when BH-BD servings were doubled. At-home scores for stimulation and sedation did not differ between groups. BH-BD significantly increased blood ketone concentrations 1-h post-consumption. No clinically meaningful changes in safety measures including vital signs and clinical laboratory measurements were detected within or between groups. These results support the overall tolerability and safety of consumption of up to 25 g/day BH-BD.  相似文献   
998.
999.
1000.
We searched for predictors of essential hypertension in 1,031 persons aged 30-49 who were observed to progress from normotension to hypertension, as compared to an equal number of matched subjects who remained normotensive. Blood pressure status was well documented in both multiphasic screenings and clinical records. Compared to persons with each lighter eye color, those with brown eyes were more prone to develop hypertension, with relative risk of 1.5 (95% confidence interval 1.18-1.96) compared to all persons with nonbrown eyes. The association persisted after control for race, sex, body mass index, alcohol use, educational level, parental history of hypertension, and among whites, for ethnic origin as crudely estimated by last name. Partial confirmation was obtained in three largely independent study groups: 1) 25 pairs of eye-color-discordant dizygotic twins; 2) 894 pairs of incident hypertensives and controls selected only with multiphasic screening blood pressure measurements; and 3) cross-sectional analysis of 152,018 multiphasic screenees. The weak association of eye color with hypertension clearly requires further confirmation. Although it has little potential for use in screening or clinical care, it may have implications regarding etiology. Areas for further exploration include the close metabolic relation of melanins to catecholamines, both derived from the amino acid tyrosine, and the possibility that dark-eyed persons react more quickly and strongly to stimuli than light-eyed persons.  相似文献   
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