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21.
Among a consecutive series of 9,279 sternotomies performed during a period of 2(1/2) years, 61 (0.66%) patients developed significant wound complications. Of these, 58 (95.1%) survived. Sternal infection occurred in 36 patients (0.39%). Predisposing factors included chronic obstructive pulmonary disease, diabetes mellitus, obesity, closed chest massage, prolonged assisted ventilation, and excessive bleeding after operation. Positive end expiratory pressure (PEEP) did not, in itself, predispose to sternal dehiscence. Intermittent positive pressure breathing (IPPB) treatments caused excessive coughing, which may have increased the likelihood of dehiscence. Disposable drapes and expeditious surgery probably contributed to the low incidence of wound infection. Early diagnosis, surgical debridement, rewiring and primary closure with substernal drainage, without continuous antibiotic irrigation, resulted in satisfactory resolution in most patients.  相似文献   
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Persistent atrial paralysis in a patient with complete heart block and mild mitral insufficiency is presented. Left atrial specimens obtained during implantation of a permanent cardiac pulse generator showed evidence of hypertrophy and fibrosis; subcellular degenerative changes ranged from near normal to irreversible, thus suggesting that atrial paralysis may be due to the replacement of normal atrial muscle with nonfunctional fibrous tissue.  相似文献   
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Dissatisfaction with the hemodynamic characteristics of available porcine valves prompted a clinical trial of the Ionescu-Shiley percardial xenograft (ISPX) valve. Three hundred fifty-six ISPX valves were implanted consecutively in 326 patients. Operative mortality was 2.6% (2/75) for aortic valve replacement alone and 7.7% (12/155) for aortic valve replacements that included reoperations and combined procedures such as mitral commissurotomy, annuloplasty, and coronary artery bypass. Operative mortality for all patients who underwent mitral valve replacement was 9.5% (14/147). The mean peak systolic gradient pressure in the aortic position was 5.4 mm Hg overall and 4.27 mm Hg with the size 19 mm valve. There were no embolic episodes in patients who received the ISPX valve in the aortic position. The available data indicate that the rate of peripheral embolism with the ISPX valve compares favorably with that of porcine valves. Considering its hemodynamic advantage, if the longterm durability of the full-orifice Ionescu-Shiley pericardial xenograft valve continues to be confirmed by follow-up studies, it is our opinion that it is the biologic valve of choice.  相似文献   
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Incorporation of tritium from tritiated water into lipid fractions was measured in isolated hepatocytes from rainbow trout (Salmo gairdneri) acclimated to 5 degrees C and 20 degrees C. Hepatocytes from cold-acclimated trout exhibited significantly higher rates of tritium incorporation into both fatty acid and sterol fractions at assay temperatures of 15 degrees C and 20 degrees C than did hepatocytes from warm-acclimated trout. Tritium incorporation into the fatty acid fraction was nearly temperature independent in hepatocytes from warm-acclimated trout (Q10 = 1.39) but markedly temperature dependent (Q10 = 2.63) in hepatocytes from cold-acclimated trout; in contrast, rates of sterol synthesis were more temperature dependent in warm-acclimated trout. At 5 degrees C, fatty acid lipogenesis comprised a significantly greater percentage of the total tritium incorporation in hepatocytes from warm-acclimated trout and the percentage of total lipogenesis attributable to fatty acids decreased significantly in warm-acclimated trout as the assay temperature increased; the opposite trends were observed in cold-acclimated trout.  相似文献   
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Two bacteriophage T4-induced, nucleic acid-modifying activities, 5′ polynucleotide kinase and 3′ phosphatase, are both coded by the pseT gene. Therefore, the product of this gene is an enzyme which can remove phosphates from 3′ termini and add them to 5′-hydroxyl termini and thus could be said to “shuttle” phosphates on polynucleotides. This enzyme is sometimes required for T4 true-late gene expression, probably by helping establish the required intracellular DNA structure. Our data suggest that a host gene product normally can substitute for the product of the pseT gene, making it non-essential for phage multiplication on most laboratory strains of Escherichia coli.  相似文献   
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A 10-month-old infant was found to have an isolated congenital arteriovenous fistula between the right subclavian artery and vein. Ligation of the fistula resulted in complete anatomic correction and rapid resolution of cardiomegaly.  相似文献   
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