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101.
102.
The FAO/WHO/UNU recommendations for energy requirements assume that the energy cost of sleep is equal to the basal metabolic rate (BMR). We have tested the validity of this assumption by analysing overnight and BMR measurements made by whole-body indirect calorimetry. Data from 80 healthy subjects measured on a total of 246 occasions have been used. In a subgroup of 40 normal lean subjects the mean ratio of overnight metabolic rate (Overnight MR): BMR was 0.95 (range 0.85 - 1.02, s.d. 0.04). The mean ratio of lowest sleeping metabolic rate (Lowest SMR): BMR was 0.88 (range 0.83 - 0.96, s.d. 0.04). Ratios of Overnight MR: BMR were not significantly affected by different levels of exercise on the preceding day. This ratio was significantly higher for subjects who were obese, late pregnant or attached to ECG electrodes. With the exception of the late pregnant subjects these groups had the same Lowest SMR:BMR ratios as the normal lean subjects, indicating that the higher Overnight MR was caused by disturbed sleep. The data suggest that the use of BMR to estimate overnight energy expenditure would introduce an average overestimate of approximately 5 per cent during the actual hours of sleep, but that when applied over 24 h the error becomes negligible.  相似文献   
103.
Toxicity of diethyltoluamide-containing insect repellents   总被引:1,自引:0,他引:1  
M H Davies  R J Soto  R D Stewart 《JAMA》1988,259(15):2239-2240
  相似文献   
104.
Eleven post-menopausal women presenting with a parasymphyseal insufficiency fracture of the pubis are reported. The plain radiographs showed delayed healing with a mixed lytic and sclerotic area developed at the fracture site simulating a malignant lesion. Aetiological factors included post-menopausal osteoporosis, rheumatoid arthritis and steroid therapy, previous hip replacement and pelvic radiotherapy. Ten patients had concomitant fractures of the pelvis, including nine with sacral fractures. These were all initially missed on presentation because of the subtle radiographic signs of a longitudinal band of sclerosis, usually bilaterally, in the sacral ala. Bone scanning was shown to be the most sensitive technique in detecting the sacral fractures by demonstrating increased uptake in the sacral ala as well as the other fractures of the pelvis. Computed tomography in three cases was helpful in confirming the presence of fractures and excluding the possibility of malignancy.  相似文献   
105.
106.
Summary Since 1992, efforts have been made to combat onchocerciasis in Guatemala through mass distribution of ivermectin. The impact of the campaign is assessed by taking skin-snips from sentinel groups within selected communities. This method gives an estimate of the prevalence and intensity of infection, and thus the efficacy of the treatment. In some communities people are becoming reluctant to volunteer for skin-snipping, and so there is a need for an alternative technique that will give quantitative results. In most hyperendemic communities in Guatemala, biting blackflies are so ubiquitous that few people object to allowing 10 to 20 flies to engorge upon them. We examined data on the quantitative uptake of microfilariae by Simulium ochraceum before and after ivermectin distribution to see whether results similar to skin-snip data could be obtained. Counts of microfilariae ingested by S. ochraceum are compared to the numbers found in skin-snips from the same volunteers. In a group of 31 untreated infected persons, a skin-snip survey detected 64.5% positive, while feeding flies (vector microfilarial uptake, VmfU) detected 96.8%. Post-treatment, in a sample of 58 of whom 52 (89.7%) had a history of infection, both skin-snips and VmfU detected 54.2%. Vector blood meals contained more microfilariae than a mg of skin before treatment, but both recorded about equal numbers after treatment. When the data set was subdivided to compare samples taken at 2–3, 6–8 and 14–17 months post-treatment, the effect of ivermectin was still apparent at 6–8 months, but had virtually disappeared by 14 months post-treatment. A surprising observation was that the flies ingested fewer microfilariae from treated persons than was expected from the skin densities as estimated by skin-snip. This effect lasted for over 8 months, and could indicate that ivermectin has a greater effect on transmission than previously suspected. We conclude that VmfU could be used as an alternative to skin-snipping, and discuss the ethical implications.  相似文献   
107.
Fluoxetine in panic disorder   总被引:4,自引:0,他引:4  
Twenty-five patients with a primary DSM-III-R diagnosis of panic disorder with or without agoraphobia were treated openly with the serotonin uptake inhibitor fluoxetine for up to 12 months. For most patients, treatment was initiated at 5 mg/day to minimize adverse effects previously reported with initiation at higher doses. Nineteen (76%) experienced moderate to marked improvement in panic attacks. Four (16%) were unable to tolerate fluoxetine due to adverse effects. Initiating treatment of panic disorder with low doses of fluoxetine may increase its acceptability and permit more patients to benefit from fluoxetine.  相似文献   
108.
109.
O J Corrado  C A Gould  J Y Kassab    R J Davies 《Thorax》1986,41(11):863-868
The nasal responses to provocation with histamine and methacholine were compared in 20 subjects with and 20 without rhinitis. Two variables were measured: nasal airways resistance and the development of rhinorrhoea. Histamine had a greater effect than methacholine in increasing nasal airways resistance while the converse was true for rhinorrhoea. Rhinitic subjects had a significantly greater response to histamine induced changes in nasal airways resistance (p less than 0.05), rhinorrhoea (p less than 0.05) and methacholine induced rhinorrhoea (p less than 0.01) than those without rhinitis. No significant differences were found between the two groups in methacholine induced changes in nasal airways resistance. The findings show that, like the lower airways of patients with asthma, the nasal mucosa of rhinitic subjects shows a greater responsiveness to non-specific agonists than that of non-rhinitic subjects.  相似文献   
110.
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