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A single honey bee mariner transposon (TnM1a) was sequenced, revealing a transpositionally non-autonomous element of 937 bp delimited by 30 bp perfect inverted terminal repeats. The element is flanked by the TA duplication typical of mariner elements in general. There are approximately 435 copies of TnM1a homologous elements per haploid genome. These elements appear, by Southern blot analysis, to be dispersed throughout the genome. Thirteen individual genomic clones with an average size of 15 kb, were found to contain only a single element each, which also suggests that the elements are not tightly clustered. Finally, mariner elements are neither inactivated by methylation nor sequestered into a methylated fraction of the genome.  相似文献   
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Because reporting of complications by physicians is not reliable, monitoring of the hospital course of surgical patients by nurses can improve effectiveness of identifying complications. Monitoring the course of only those patients who remain in the hospital more than four postoperative days will disclose 90 per cent of complications expected in all patients undergoing operation. Twenty hours per week of a nurse's time is sufficient to monitor 1,300 such patients annually. Identification of patients with large hospital bills will include most patients with complicated hospital courses but does not discriminate them from the large number of uncomplicated courses which also generate large hospital charges.  相似文献   
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After inhaling fluoroalkane gases, which are used as aerosol propellants, some people have died suddently and unexpectedly. Seeking an explanation, we had 14 monkeys inhale these gases. All developed ventricular premature beats, bigeminy, or tachycardia, which began at an average of 39 (SE +/-4.2) sec. Fluoroalkanes were present in blood, but arterial hypoxemia or hypercapnia was absent, and arterial pressure was reduced only slightly. In contrast, without fluoroalkanes, 3 min of asphyxia or anoxia caused arrhythmias in only one monkey whose arterial oxygen tension had fallen to 16 mm Hg. The ventricular arrhythmias caused in well oxygenated monkeys by fluoroalkane gases may either be mediated through beta adrenergic receptors, since propranolol abolished these arrhythmias, or result from a nonadrenergic, direct, toxic effect of these gases on the heart. These results suggest that some deaths after propellant inhalation may be caused by ventricular tachycardia or fibrillation.  相似文献   
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Twelve carbohydrate-sensitive and 12 non-carbohydrate sensitive (normal) men were studied. Carbohydrate sensitivity was identified by hyperinsulinemic and normoglycemic responses to a sucrose load. In a blocked split-plot design, fasted subjects were given 2 g/kg body weight of sucrose or invert sugar, and responses of plasma zinc, copper, insulin, and glucose were determined. Erythrocyte zinc and copper also were measured. Blood samples were taken 0, 0.5, 1, 2, and 3 hours after the sugar loads were given. Plasma zinc, copper, insulin, and glucose did not differ significantly between the two sugar loads. Neither did erythrocyte zinc and copper differ significantly between the two load doses. Also, plasma zinc, copper, and glucose, as well as erythrocyte zinc and copper, did not differ significantly between the carbohydrate-sensitive and normal men. Plasma insulin was significantly higher in the carbohydrate-sensitive than the normal men. Plasma zinc did not change significantly between sampling times. Plasma copper declined progressively over the testing period. The greater the elevation of plasma glucose above the fasting level, the greater the plasma copper was depressed. Copper appears to be withdrawn from plasma after sugar loading to facilitate glucose uptake and metabolism.  相似文献   
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A case of congenital orbital teratoma is presented with illustrations and discussion of typical radiographic features which may facilitate preoperative diagnosis and treatment.  相似文献   
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