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Objective  To study associations between maternal dietary and supplement intake of antioxidants vitamin E, retinol and congenital heart defects (CHDs).
Design  Case–control study.
Setting  Erasmus MC, University Medical Center Rotterdam, the Netherlands.
Population  Participants were 276 case mothers of a child with CHD and 324 control mothers with their children.
Methods  Food frequency questionnaires covering the intake of the previous 4 weeks were filled out at 16 months after the index pregnancy. Data were compared between cases and controls using the Mann–Whitney U test. Risk estimates for the association between CHD and dietary intake of vitamin E and retinol were estimated in a multivariable logistic regression model.
Main outcome measures  Medians (5–95th percentile) and odds ratios with 95% CI.
Results  Dietary vitamin E intake was higher in case mothers than in controls, 13.3 (8.1–20.4) and 12.6 (8.5–19.8) mg/day ( P = 0.05). CHD risk increased with rising dietary vitamin E intakes ( P -trend = 0.01). Periconception use of vitamin E supplements in addition to a high dietary vitamin E intake above 14.9 mg/day up to nine-fold increased CHD risk. Retinol intakes were not significantly different between the groups and not associated with CHD risk.
Conclusions  High maternal vitamin E by diet and supplements is associated with an increased risk of CHD offspring.  相似文献   
144.

OBJECTIVE

To assess the relationship between habitual sleep disturbances and the incidence of type 2 diabetes and to obtain an estimate of the risk.

RESEARCH DESIGN AND METHODS

We conducted a systematic search of publications using MEDLINE (1955–April 2009), EMBASE, and the Cochrane Library and manual searches without language restrictions. We included studies if they were prospective with follow-up >3 years and had an assessment of sleep disturbances at baseline and incidence of type 2 diabetes. We recorded several characteristics for each study. We extracted quantity and quality of sleep, how they were assessed, and incident cases defined with different validated methods. We extracted relative risks (RRs) and 95% CI and pooled them using random-effects models. We performed sensitivity analysis and assessed heterogeneity and publication bias.

RESULTS

We included 10 studies (13 independent cohort samples; 107,756 male and female participants, follow-up range 4.2–32 years, and 3,586 incident cases of type 2 diabetes). In pooled analyses, quantity and quality of sleep predicted the risk of development of type 2 diabetes. For short duration of sleep (≤5–6 h/night), the RR was 1.28 (95% CI 1.03–1.60, P = 0.024, heterogeneity P = 0.015); for long duration of sleep (>8–9 h/night), the RR was 1.48 (1.13–1.96, P = 0.005); for difficulty in initiating sleep, the RR was 1.57 (1.25–1.97, P < 0.0001); and for difficulty in maintaining sleep, the RR was 1.84 (1.39–2.43, P < 0.0001).

CONCLUSIONS

Quantity and quality of sleep consistently and significantly predict the risk of the development of type 2 diabetes. The mechanisms underlying this relation may differ between short and long sleepers.Sleep patterns of quantity and quality are affected by a variety of cultural, social, psychological, behavioral, pathophysiological, and environmental influences. Changes in modern society include longer working hours, more shift-work, and 24-7 availability of commodities. These changes are paralleled by secular trends of curtailed duration of sleep to fewer hours per day across westernized populations (1). These trends have led to increased reporting of fatigue and tiredness and excessive daytime sleepiness (2). Lack of sleep exerts deleterious effects on a variety of systems with detectable changes in metabolic (3,4), endocrine (5,6), and immune pathways (7).Short-term, acute, laboratory, and cross-sectional observational studies indicate that disturbed or reduced sleep is associated with glucose intolerance, insulin resistance, reduced acute insulin response to glucose, and a reduction in the disposition index (4), thus predisposing individuals to type 2 diabetes. The causality of the association and the generalizability of the results to longer-term effects of sustained sleep disturbances have been studied in prospective population studies to establish a temporal sequence between exposure and outcome. Because of the large differences in the types and sizes of populations examined, the duration of follow-up, and the size of the effects, it is difficult to draw immediate conclusions on the consistency of the associations and the size of the effect. Our aim was to review published prospective population-based studies to assess whether the global evidence supports the presence of a relationship between sleep disturbances (in quantity and quality) and the development of type 2 diabetes and to obtain a quantitative estimate of the risk.  相似文献   
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经皮椎体注入骨水泥治疗老年脊椎骨质疏松压缩性骨折   总被引:4,自引:0,他引:4  
目的:观察经皮椎体内注入骨水泥(聚甲基丙烯酸甲酯)治疗脊椎骨质疏松压缩性骨折的疗效。方法:自2005-06/2006-06吉林大学中日联谊医院骨科及大庆龙南医院骨科对35例40个椎体的骨质疏松压缩性骨折患者使用经皮椎体内注射骨水泥,行椎体成形术。成形材料:美国KYPHON公司生产的骨水泥,生产准许号:(GB/T19001-2000和YY/T0287-1996)。结果:35例患者均参加随访6个月。术后均未出现骨水泥外漏、脊髓或马尾神经损伤等并发症。35例患者中5例出现穿刺部位局部疼痛,服用镇痛药物后均缓解。疼痛完全消失25例,占71.4%;明显缓解8例,占22.6%;轻度缓解2例,占6.0%;无缓解0例。15例患者在术后72h内均能下床活动。术后未再发生压缩性骨折及疼痛。结论:经皮椎体注入骨水泥可以有效改善椎体骨质疏松压缩性骨折患者疼痛症状,随访6个月未出现充填剂不良性宿主反应,临床疗效较好。  相似文献   
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Malignant uveal melanoma and similar lesions studied by computed tomography   总被引:2,自引:0,他引:2  
Mafee  MF; Peyman  GA; McKusick  MA 《Radiology》1985,156(2):403-408
Forty-four patients with intraocular disease were studied by computed tomography (CT); in 19 cases malignant uveal melanoma was considered the likely diagnosis. CT proved to be accurate in determining the location and size of uveal melanomas, demonstrating scleral invasion, and differentiating melanoma from choroidal detachment or angioma, toxocariasis, and senile macular degeneration. Astrocytic retinal hamartoma and medulloepithelioma could not be distinguished from melanoma with CT. On CT, uveal melanomas appeared as hyperdense lesions with slight to moderate contrast enhancement. Tumors thinner than 2 mm could not be seen. Using dynamic CT, we noted moderate peak amplitude, normal or delayed tissue transit time, and persistently elevated washout phase (downslope), indicating increased permeability as the result of an impaired tumor blood barrier. Histological types of uveal melanoma could not be differentiated on the basis of circulatory patterns. Dynamic CT may be useful in distinguishing uveal melanoma from choroidal hemangioma or hematoma.  相似文献   
150.
Thirty-five normal two-month-old infants had nighttime followed by daytime polygraphic recordings. Heart rates were calculated every minute in active and quiet sleep states. A difference in mean heart rates was found between the two states and between the two recordings. Rates were lower at night than during the day (P < 0.0001), regardless of the sleep state. During nighttime or daytime recordings as a function of sleep cycles or during sustained sleep episodes, heart rates were minimal in the middle of recordings, but differences were statistically significant for only a few results (mainly in QS). Intrasleep awakening led to a marked increase in heart rate after sleep was resumed, although differences were only statistically significant when the awakened infant was fed. Infants with episodes of periodic breathing had lower mean heart rates throughout the recordings, but differences were not statistically significant. Respiratory and heart rates showed similar changes during the recordings, and a statistically significant correlation was found between the two measurements.  相似文献   
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