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1.
We analyzed our experience with 64 infants with esophageal atresia (EA) and tracheoesophageal fistula (TEF), to determine the possibility of prediction and prevention of anastomotic complications (leak, stricture, and recurrent TEF). In most of the infants, the anatomical level of the fistula was documented preoperatively by bronchoscopy. The level of the fistula, in turn, correlated with the esophageal anatomy at thoracotomy, ie, carinal fistulas had a wide gap between esophageal pouches, whereas midtracheal or cervical fistulas had a minimal gap. Major anastomotic complications were defined as leak requiring reoperation, symptomatic strictures requiring four or more dilatations, or a recurrent TEF. The complication rates wre: leak (major and minor), 21%; major stricture, 15%; and recurrent TEF, 5%. Major complications occurred in 42% (11/26) of infants with wide gaps, compared with 8% (3/36) of infants with minimal gaps. Route of repair (transpleural or retropleural) made no difference in incidence of anastomotic complications. No infant died of an anastomotic complication. Survival was 100% for Waterston A and B infants, 83% for Waterston C, and 90% overall. Severe gastroesophageal reflux, requiring Nissen fundoplication, was more common among infants with wide gaps than those with minimal gaps (32% v 3%). The most important pathogenetic factor, present in 79% (11/14) of major anastomotic complications, was anastomotic tension, determined by the gap between esophageal pouches, and predicted by preoperative bronchoscopy. Thus the bronchoscopic finding of a carinal fistula signals the need for technical measures that may limit anastomotic morbidity, such as myotomy, patching the anastomosis, retropleural approach, or delayed repair. Assuming precise technique and gentle handling of tissues, the anatomy of the anomaly determines the anastomotic morbidity of EA and TEF.  相似文献   
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Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive.  相似文献   
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We evaluated the clinical usefulness of species identification of blood isolates of coagulase-negative staphylococci as a predictor of the clinical significance of the isolates. In addition, we compared results of species identification obtained with MicroScan Rapid Gram-Positive Identification panels and Dried Overnight (Conventional) Gram-Positive Identification panels with those obtained by a tube reference method. Two hundred eighty-five blood isolates were tested, including 92 judged to represent true bacteremia and 193 judged to represent contamination. The most common species detected were Staphylococcus epidermidis, Staphylococcus hominis, and Staphylococcus haemolyticus. These three species accounted for nearly 98% of the clinically significant isolates and 89% of the contaminants. The isolation of other species almost always represented contamination. However, identification of the three most common species did not help distinguish pathogens from contaminants. Both the Rapid and the Dried Overnight Gram-Positive panels identified S. epidermidis strains accurately, but the panels performed less well for the other species. Analysis revealed that S. hominis was frequently misidentified due to the presence of a previously unknown subspecies. Based on the initial results, revised investigational Dried Overnight Gram-Positive Identification panels (CPID-2) were prepared and tested. The CPID-2 panels identified 85 to 95% of S. epidermidis strains, 76 to 86% of S. hominis strains, and 88 to 92% of S. haemolyticus strains with high probability (>85%) and, overall, represented a significant improvement over the other panels for identification of these staphylococcal species.  相似文献   
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The ATM protein kinase is activated by intermolecular autophosphorylation in response to DNA damage and initiates cellular signaling pathways that facilitate cell survival and reduce chromosomal breakage. Here, we show that NBS1 and BRCA1 are required for the recruitment of previously activated ATM to the sites of DNA breaks after ionizing irradiation, and that this recruitment is required for the phosphorylation of SMC1 by ATM. To explore the functional importance of SMC1 phosphorylation, murine cells were generated, in which the two damage-induced phosphorylation sites in SMC1 are mutated. Although these cells demonstrate normal phosphorylation and focus formation of ATM, NBS1, and BRCA1 proteins after IR, they exhibit a defective S-phase checkpoint, decreased survival, and increased chromosomal aberrations after DNA damage. These observations suggest that many of the abnormal stress responses seen in cells lacking ATM, NBS1, or BRCA1 result from a failure of ATM migration to sites of DNA breaks and a resultant lack of SMC1 phosphorylation.  相似文献   
10.
We report a novel DQA1 allele (DQA1*0403N) identified during sequence-based HLA-DQA1 typing of a Kenyan population. The new allele is identical to DQA1*0401 at exon 2 except for a single-nucleotide substitution at codon 53, changing it from lysine to a stop codon (CAA-->TAA). The substitution at codon 53 was confirmed by sequencing two separate polymerase chain reaction products and by sequencing multiple clones obtained following TOPO-TA cloning. The resulting stop codon at position of codon 53 in exon 2 is predicted to produce a non-functional DQA1 alpha-chain. The new allele has been named by the WHO nomenclature committee as DQA1*0403N. This is the first report of a null allele detected in the DQA1 gene.  相似文献   
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