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Assessing obesity: classification and epidemiology   总被引:1,自引:0,他引:1  
Obesity is generally defined as a body mass index (BMI) of 30 kg/m2 and higher. Overweight is defined as a BMI between 25 and 30 kg/m2. The prevalence varies considerably between countries, and between regions within countries. It is estimated that more than half of adults aged 35-65 living in Europe are either overweight or obese. Overweight is more common among men than among women but obesity is more common among women. The prevalence of obesity in Europe is probably in the order of 10-20% in men and 15-25% in adult women. In most European countries who have reliable data on time-trends the prevalence of obesity seems to be increasing. In most European countries, obesity is usually inversely associated with socio-economic status, particularly among women. New classifications of overweight may be based on cut-off points for simple anthropometric measures which reflects both total adiposity as well as abdominal fatness.  相似文献   
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Following the phenomenal success of second generation global system for mobile communications (GSM) systems, the world has turned its attention to third generation mobile systems (3G). New radio spectrum has been allocated for these networks and over the last 12 months there has been global activity to license this spectrum. Licences have been awarded in a number of ways including 'beauty contests' and (often costly) auctions. Technologists have joined forces to specify the standards for 3G. This paper describes the drivers for 3G and the commercial model that is emerging. The benefits that 3G technology will provide for business and consumer products are identified. A component-based approach to application and product development is described, based on the important value add features of mobile systems. Finally, mobile terminals, billing and payment, and customer care are also considered as they are vital to the overall customer experience.  相似文献   
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An unusual case of chylothorax is described in a 4-year-old child after repair of a ventricular septal defect and ligation of a patent ductus arteriosus through a median sternotomy. Left chylothorax developed after a latent period of six days and was treated initially with continuous drainage and parenteral supplementation of proteins and lipids. Operative intervention with oversewing of the site of the leak in the anterior mediastinum proved necessary after three weeks. The anatomical variations of the thoracic duct are outlined to explain the occurrence of chylothorax after diverse intrathoracic operations. The physiological effects of a thoracic duct fistula and various aspects of management are reviewed.  相似文献   
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In many patients with migraine, several localised areas usually on the scalp or neck can be identified. The local injection of lignocaine one per cent and adrenaline 1/200,000 often leads to considerable relief of the symptoms of migraine including visual phenomena. The common sites of the trigger areas are shown and several uncontrolled case reports of the effect of the treatment are described.  相似文献   
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Serial endocrine studies were performed during the refeeding of a group of nine young women who presented with amenorrhea associated with injudicious dieting. No significant psychopathology was disclosed by the Lanyon Psychological Screening Inventory in any of the patients, six of whom were single and three married and infertile. The mean weight before refeeding was 81.6% of the normal for height. The mean initial serum follicle-stimulating hormone concentration was within the limits of normal for young women of reproductive age, but the serum luteinizing hormone (LH) concentration and the vaginal maturation score were low. As weight was regained, the serum LH concentration increased (the pooled r for LH versus percent normal weight = 0.85) and the vaginal maturation score rose (the pooled r for vaginal maturation score versus percent normal weight = 0.93). When a mean weight of 96.6% of normal was reached after a mean of 5.3 (range, 2 to 11) months of refeeding, spontaneous menses occurred. The initial cycle was ovulatory in two instances and anovulatory in five, as determined by basal body temperature patterns, plasma progesterone concentrations, and endometrial biopsies. With continued weight gain, menstruation became regular and the three married patients conceived.  相似文献   
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Investigation of the serum of three patients with positive antibody detection tests demonstrated the cause in each to be an antibody against chloramphenicol, a bacteriostatic agent used in commercial red blood cell reagents. Washing of these red cells prior to use prevented agglutination. All three examples of anti-chloramphenicol antibody were IgM and were in low titer when tested at room temperature and 37 C in saline. Two of the antibodies bound complement. The possibility of an antibody to an ingredient of the commercial preservative solution should be considered if problems are encountered in tests with unwashed commercial red blood cell reagents.  相似文献   
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We compared development of feline hindlimb collateral circulation after acute occlusion of the terminal aorta by ligation, thrombus formation, and formation of a "closed" aortic loop containing thromboplastin. Collateral circulation development was assessed by aortograms, scintillation scans, neurological signs following occlusion, measurement of hindlimb muscle blood flow, and forelimb and hindlimb temperature. In cats in which aortic occlusion was the result of ligation or thromboplastin in the aortic loop, paralysis was not evident. Aortograms and scintillation scans indicated hindlimb blood flow. Both muscle temperature and blood flow data indicated that the return of blood flow was rapid. The 5th lumbar artery appears to be the origin of the collateral vessels. The mid-zone component is a dorsal and ventral vertebral route and an epaxial muscle route. The reentry components are the 6th or 7th lumbar arteries. The collateral vessels arise from preexisting collateral vessels. Of those cats in which aortic occlusion was the result of a thrombus, all exhibited paralysis. Aortograms, scintillation scans, muscle temperature, and hindlimb blood flow data indicated reduced hindlimb blood flow. The results suggest that the thrombus has an inhibitory effect on the development of collateral circulation.  相似文献   
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