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41.
Transaxillary muscle-sparing patent ductus arteriosus closure performed as same-day surgery is described in 10 patients. This approach provides a superb cosmetic result while obviating the need for thoracostomy tube placement.  相似文献   
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A unique case of haematemesis due to a pyloroduodenal ulcer caused by an erosion by a 3 cm gallstone impacted in the duodenal bulb is presented. This is the first case where the localisation of a severe haemorrhage due to a complication of a duodenal biliary fistula is identified.  相似文献   
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On the basis of Gray's theory, Quay suggested that conduct disorder (CD) is associated with a Behavioural Activation System (BAS) that dominates over the Behavioural Inhibition System (BIS), whereas attention deficit hyperactivity disorder (ADHD) is characterised by an underactive BIS. Two studies were conducted to test the hypothesis that the dominance of the BAS over the BIS is more pronounced in CD comorbid with ADHD (CD/ADHD) than in CD alone. First of all, a response perseveration task was used, i.e. the door-opening task (Daugherty & Quay, 1991). In this game, the subject chooses either to open the next door or to stop playing; there is a steadily increasing ratio of punished responses to rewarded responses and a large number of doors opened is indicative of response perseveration. As expected, a steady increase in the number of doors opened was found across normal control (NC) boys, CD boys, and CD/ADHD boys (NC < CD < CD/ADHD). Second, the dominance of the BAS over the BIS was examined by observing the social behaviour of the child in interaction with a research assistant who alternately activated the BAS and the BIS while a game was played. The behaviour of the children was analysed according to ethological methods. Group differences in the frequencies of three out of five behavioural categories were in line with the results of the door-opening task (NC < CD < CD/ADHD).  相似文献   
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The role of the beta-93 cysteine residue in the hemoglobin autoxidation process has been delineated by electron paramagnetic resonance. At low temperatures (8 K) after incubation at 235 K, free radical signals were detected. An analysis of the free radical spectrum produced implies that, besides the superoxide radical expected to be formed during autoxidation, an isotropic free radical is produced with a giso of 2.0133. This g value is consistent with that expected for a sulfur radical. Blocking the beta-93 sulfhydryl group with N-ethylmaleimide was found to eliminate the formation of the isotropic radical, but not the superoxide. This finding confirms the assignment of the isotropic radical as a thiyl radical originating from the oxidation of the cysteine SH group. A kinetic analysis of the time course for the formation of both the superoxide and thiyl radicals is consistent with a reversible electron transfer process between superoxide in the heme pocket of the beta-chains and the cysteine residue. This reaction is expected to produce both a thiyl radical and a peroxide. Direct evidence for peroxide production comes from the detection of a transient Fe(III) heme peroxide complex. The significance of the electron transfer process producing a thiyl radical is discussed. It is shown that the formation of the thiyl radical decreases the rate of autoxidation for the beta-chain and reduces heme degradation attributed to the reaction of superoxide with the heme. The insights gained from these low-temperature studies are believed to be relevant to room-temperature autoxidation.  相似文献   
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1. A spectrophotometric assay using rho-iodo-nitro-triphenyl tetrazolium chloride as the indicator was developed for splenic tissue in the goldfish Carassius auratus. 2. This technique permits a rapid test for the activities of the enzymes lactic dehydrogenase, malic dehydrogenase, and alpha-glycerophosphate dehydrogenase which are indicative of the relative activities of various metabolic pathways.  相似文献   
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The serum activities of aspartate aminotransferase, alanine aminotransferase, alpha-hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed.  相似文献   
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