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排序方式: 共有4132条查询结果,搜索用时 15 毫秒
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Fabian Heinrich Kira Meißner Felicia Langenwalder Klaus Püschel Dominik Nrz Armin Hoffmann Marc Lütgehetmann Martin Aepfelbacher Eric Bibiza-Freiwald Susanne Pfefferle Axel Heinemann 《Emerging infectious diseases》2021,27(1):329
Analyses of infection chains have demonstrated that severe acute respiratory syndrome coronavirus 2 is highly transmissive. However, data on postmortem stability and infectivity are lacking. Our finding of nasopharyngeal viral RNA stability in 79 corpses showed no time-dependent decrease. Maintained infectivity is supported by virus isolation up to 35 hours postmortem. 相似文献
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Chew EY 《Current opinion in ophthalmology》1997,8(3):59-62
The relationship of serum lipid levels and diabetic retinopathy has interested clinicians for several decades. Data from both a population-based study of diabetic retinopathy and a controlled, randomized trial of laser photocoagulation and aspirin treatment in diabetic retinopathy have provided further information regarding the importance of the role of serum lipids in patients with elevated serum lipid levels and diabetic retinopathy. Retinal hard exudate, which is accompanied by macular edema, is associated with elevated serum lipid levels. Although the data are observational, visual loss is likely to be associated with retinal hard exudate and serum lipid abnormalities. These relationships are evaluated in the analyses of the data from the Early Treatment Diabetic Retinopathy Study. 相似文献
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Chew EY 《Current opinion in ophthalmology》1995,6(3):19-24
Age-related macular degeneration is one of the leading causes of visual loss among people aged 65 years or older. The causes and factors associated with the progression of age-related macular degeneration are unknown presently. Basic research and epidemiologic data support the hypotheses that higher levels of antioxidant vitamins and minerals may protect the eye from the development of age-related macular degeneration. For this reason and also because of the lack of effective treatment for most cases of age-related macular degeneration, nutritional supplements with antioxidants have emerged as possible therapy for age-related macular degeneration. Nutritional supplements are not proven therapy for age-related macular degeneration. The potential beneficial effects and adverse side effects of the nutritional supplements have not yet been fully evaluated in carefully conducted clinical trials. Several randomized placebo-controlled clinical trials are presently underway. Results of these studies will provide important data to clarify the potential beneficial and adverse effects of such treatment. Until these results are available, it would be premature to make recommendations in favor of vitamin or mineral supplements. 相似文献
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Christen WG Ajani UA Glynn RJ Manson JE Schaumberg DA Chew EC Buring JE Hennekens CH 《American journal of epidemiology》1999,149(5):476-484
In a prospective cohort study, the authors examined whether self-selection for antioxidant vitamin supplement use affects the incidence of age-related maculopathy. The study population consisted of 21,120 US male physician participants in the Physicians' Health Study I who did not have a diagnosis of age-related maculopathy at baseline (1982). During an average of 12.5 person-years of follow-up, a total of 279 incident cases of age-related maculopathy with vision loss to 20/30 or worse were confirmed by medical record review. In multivariate analysis, as compared with nonusers of supplements, persons who used vitamin E supplements had a possible but nonsignificant 13% reduced risk of age-related maculopathy (relative risk = 0.87, 95 percent confidence interval (CI) 0.53-1.43), while users of multivitamins had a possible but nonsignificant 10% reduced risk (relative risk = 0.90, 95% CI 0.68-1.19). Users of vitamin C supplements had a relative risk of 1.03 (95% CI 0.71-1.50). These observational data suggest that among persons who self-select for supplemental use of antioxidant vitamin C or E or multivitamins, large reductions in the risk of age-related maculopathy are unlikely. Randomized trial data are accumulating to enable reliable detection of the existence of more plausible small-to-moderate benefits of these agents alone and in combination on age-related maculopathy. 相似文献
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Urolithiasis has long been recognized as a cause of irritative voiding in cats. Before the late 1980s, sterile struvite was the most common urolith; today, however, 40% of feline uroliths are of calcium oxalate. This change may be partly attributable to the change to urine-acidifying, magnesium-restricted diets that were introduced to reduce the formation of struvite. However, it is possible that the diet modifications made by cat food manufacturers simply exposed a population of cats predisposed to calcium oxalate stone formation. Urolithiasis in cats appears to be diet sensitive rather than diet induced. As in humans, water is crucial in the prevention and treatment of feline stones. 相似文献
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Cognitive function in the Caerphilly study: Associations with age,social class, education and mood 总被引:6,自引:0,他引:6
Gallacher JE Elwood PC Hopkinson C Rabbitt PM Stollery BT Sweetnam PM Brayne C Huppert FA 《European journal of epidemiology》1999,15(2):161-169
Baseline cognitive function was established for a study of pre- symptomatic cognitive decline in 1870 men from the general population aged 55–69 years as part of the third examination of the Caerphilly Study. Cognitive assessment included the AH4, a four choice serial reaction time task, a modified CAMCOG, MMSE, NART and various memory tests. Distributions and relationships with age, social class, education and mood at time of testing are presented for a younger population than has previously been available. Multiple linear regression showed cognitive function to be independently associated with all four factors. The age effect was equivalent to one half of a standard deviation (SD) in CRT and AH4 scores. Only the NART score was not associated with age, supporting the use of NART score as an estimate of pre-morbid IQ. The largest age adjusted differences between men with low and normal mood were for the AH4 (3 points, t=5.6, p<0.0001) and the CAMCOG (2 points, t=5.8, p<0.0001). The smallest age adjusted effect of mood was for the CRT (33ms, t=2.14, p=0.32) and the MMSE (0.4 points, t=2.97, p=0.003). Age, mood and education adjusted social class effects were very large ranging between around 0.5 SD for the CRT, and 1.0 SD for the AH4 and NART, respectively. For educational status age, mood and social class adjusted differences were also substantial with tests for trend showing the largest differences for the NART (t=12, p<0.0001) and modified CAMCOG (t=10.6, p<0.0001) with the smallest differences for the CRT (t=2.73, p=0.006). 相似文献
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Maberley DA Yannuzzi LA Gitter K Singerman L Chew E Freund KB Noguiera F Sallas D Willson R Tillocco K 《Ophthalmology》1999,106(12):2248-52; discussion 2252-3