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Repeated episodes of hypoglycaemia were observed in two girls with spinal muscular atrophy. During a 12 h fast blood glucose fell to 3.4 and 2.7 mmol/L, respectively. One girl developed hypoglycaemia and ketonuria. Reduced gluconeogenesis was probably the cause of hypoglycaemia in these patients who had a muscle mass of about 10% of bodyweight (normal 30-40%). Hypoglycaemia must be suspected and treated when patients with severe muscle wasting due to chronic neuromuscular disorders are admitted comatose. In our experience this condition is often regarded as respiratory insufficiency.  相似文献   
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The paper describes the accurate calibration of the camera transformation for a vision system consisting of a camera mounted on a robot. The calibration includes an analysis of the linearity of the camera. A knowledge of the camera transformation allows the three-dimensional position of the object points to be determined using triangulation.  相似文献   
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The problems inherent in the design and manufacture of mammographic test objects are discussed and a test object is described which may be used for assessing image quality. Some typical results from both good and bad mammographic machine/film combinations are presented.  相似文献   
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Randomized carboxyl poly(2‐ethylhexyl acrylate) (A‐1) and randomized epoxy poly(2‐ethylhexyl acrylate) (B‐1) rubbers were synthesized in the form of liquid rubber by a solution polymerization technique. The liquid rubbers A‐1 and B‐1 were characterized by 1H NMR and IR spectroscopic analysis, non‐aqueous titration, viscosity measurements and gel permeation chromatography. The liquid rubbers A‐1 (M?n = 3900 g mol?1), B‐1 (M?n = 4100 g mol?1) and a (1:1) mixture of A‐1 and B‐1 were pre‐reacted with epoxy resin separately and the modified epoxy networks were made by curing with high temperature curing agent. The modified epoxy networks were evaluated by unnotched Izod impact testing. The morphology and toughening behaviour were analysed by scanning electron microscopy. Optimum properties were obtained with the mixture of A‐1 and B‐1. Copyright © 2003 Society of Chemical Industry  相似文献   
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Navicula pelliculosa and an associated Flavobacterium sp. were isolated from the epiphyton of Scirpus maritimus, an emergent macrophyte growing in a brackish drainage dyke. Both micro-organisms possessed active transport systems for glucose uptake. In N. pelliculosa the transport system was fully induced in the dark in the absence of glucose, and subsequently inactivated when transferred to the light in the absence of the substrate. The presence of glucose during the dark induction period prevented the achievement of maximum specific activity of the transport system, while incubation at a high light intensity with or without the presence of the substrate resulted in a very marked inhibition of glucose uptake. Inhibition in the light was partially offset by blocking photosynthetic electron flow with 3'(3,4 dichlorophenyl)1'1' dimethyl urea. The transport system accumulated 3-O-methyl glucose against a concentration gradient and was highly specific for glucose as there was no competition by most of the other sugars tested. However, 6-deoxyglucose was taken up instead of glucose and this suggested that glucose was transported in a non-phosphorylated state, whereas inhibition of glucose transport activity with dicyclohexylcarbodimide implicated the involvement of an adenosine triphosphatase on the cell membrane. Inhibitors of oxidative phosphorylation tetrachlorosalicylaniline and carbonylcyanide m-chlorophenylhydrazone also inhibited glucose transport activity. The affinity of the diatom for glucose was greater than that shown by the bacterium, but the Km for glucose transport, 1.5x10-5M was too high to allow effective removal of glucose at in situ concentrations.  相似文献   
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