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Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive.  相似文献   
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Children's frequency of consumption of foods high in fat and sodium   总被引:2,自引:0,他引:2  
We administered a food frequency instrument to third-fifth grade students (n = 943) in four Texas schools. Comparison of foods reported on the food frequency questionnaire and on 24-hour dietary recalls (n = 7) produced a percent agreement of 83.3. The most frequent 25 foods accounted for 64.0% of food choices across all meals, 93.5% of breakfast choices, 76.4% of lunch choices, 70.5% of supper choices, and 76.0% of snack choices. Breads, milk, hamburger or steak, soda pop, tomato sauce or tomatoes, and cheese were the most frequently consumed foods. Fruits and juices accounted for 6.1% of total selections for boys and 6.6% for girls, while vegetables accounted for 15.7% of total selections for boys and 16.2% for girls. Fruit was more likely to be consumed for snacks than for meals, and vegetables were consumed in about the same frequency at lunch and supper and for snacks. We analyzed the total fat, saturated fat, and sodium content of the most frequently consumed foods. Seventeen of the top 25 foods for the total day and 13-16 for each meal or snack exceeded by at least 50% the recommended levels for fat, saturated fat, or sodium. The pattern of consumption was one of frequent consumption of a relatively small number of foods, many of which are high in fat or sodium.  相似文献   
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Many patients infected with HIV do not achieve or maintain virologic suppression below levels of detection while on potent combination antiretroviral therapy. The likelihood of emergence of incident mutations conferring reduced antiretroviral drug susceptibility was estimated among patients maintained on a stable regimen with ongoing detectable plasma HIV RNA levels. Ninety-eight HIV-infected patients were identified who had 2 genotypic antiretroviral resistance tests available. Poisson log-linear regression models were used to identify predictors and estimate incidence rates of number of acquired antiretroviral drug resistance mutations per person-year. At the 1st resistance test, 88% of patients had evidence of at least 1 mutation. Sixty percent of patients acquired at least 1 new mutation during a median of 9.3 months between consecutive resistance tests, with an incidence rate of 1.61 acquired mutations per person-year (95% CI: 1.36-1.90). Predictors of resistance evolution included average plasma HIV RNA level, HIV RNA slope, and number of mutations detected at the 1st resistance test. The likelihood of acquiring drug resistance mutations while remaining on potent combination antiretroviral therapy that does not confer complete suppression of HIV replication is relatively low and depends on the level of viral replication and prior resistance.  相似文献   
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