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OBJECTIVE: Surgical-site infection (SSI) is a serious and costly complication following coronary artery bypass graft (CABG). We analyzed surgical factors, microbiology, and complications at a 608-bed community teaching hospital to identify opportunities for prevention. METHODS: All patients undergoing CABG procedures from June 1997 through December 2000 were analyzed. Hospital records and postdischarge surveillance data were reviewed for demographics, surgical information, timing and classification of infection, microbiology, and bacteremic events. RESULTS: Of 3,443 patients undergoing CABG, sternal SSI developed in 122 (3.5%); 71 (58.2%) were classified as superficial SSI and 51 (41.8%) as deep SSI. Surgical antimicrobial prophylaxis was employed in all cases. On average, infection occurred 21.5 days (range, 4 to 315) after CABG. Most cases were diagnosed on readmission (59%); 20 cases (16%) were identified by postdischarge surveillance. Microbiological data were positive in 109 (89.3%), with a single pathogen implicated in most (86.2%). Gram-positive cocci were most frequently recovered (81%); gram-negative bacilli (17%), gram-positive bacilli (1%), and yeast (1%) were less common. Staphylococcus aureus was the most frequently isolated pathogen (49%). Bacteremia was noted in 22 instances (18%). It was significantly associated with deep SSI (P =. 002) and identified only in S. aureus cases. CONCLUSIONS: SSI complicated 3.5% of the procedures. S. aureus was implicated in most of the cases and was significantly associated with deep SSI. It was the only pathogen associated with secondary bacteremia. In addition to standard guidelines, targeted methods against S. aureus should help reduce the overall rate of SSI.  相似文献   
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Asymmetry in brain modulation of the immune system has been previously described. In mice, paw preference has been shown to be associated with immune reactivity but the mechanisms involved in such an association are not yet known. The autonomic nervous system and the neuroendocrine system are considered as major candidates for neural influences on the immune system. In the present study, the activity of the hypothalamic-pituitary-adrenal (HPA) axis of adult female mice selected for paw preference (left-handers vs. right-handers) was assessed by measuring both adrenocorticotropic hormone (ACTH) and corticosterone plasma levels, as well as the in vitro responses of hypothalamus and adrenocortical cells to various hormone releasing stimuli. The results reported here showed no difference in the activity of the HPA axis between left- and right-handed mice, suggesting that this neuroendocrine axis is not implicated in the association between functional brain asymmetry and immune reactivity. However, our results do not exclude the possibility that the HPA axis could play a role in such an association under other circumstances, such as during development or stressful situations.  相似文献   
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The eye movements we make to look at objects require that the spatial information contained in the objects image on the retina be used to generate a motor command. This process is known as sensorimotor transformation and has been generally addressed using simple point targets. Here, we investigate the sensorimotor transformation involved in planning double saccade sequences directed at one or two objects. Using both visually guided saccades toward stationary objects and objects subjected to intrasaccadic displacements, and memory-guided saccades, we found that the coordinate transformations required to program the second saccade were different for saccades aimed at a new target object and saccades that scanned the same object. While saccades aimed at a new object were updated on the basis of the actual eye position, those that scanned the same object were performed with a fixed amplitude, irrespective of the actual eye position. Our findings demonstrate that different abstract representations of space are used in sensory-to-motor transformations, depending on what action is planned on the objects.  相似文献   
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Novel fluorescent oligonucleotides that contain a 3' minor groove binding group (MGB) hybridize to single-stranded targets with increased sequence-specificity compared to ordinary DNA probes. This reduces non-specific probe hybridization and results in low background fluorescence during the 5' nuclease PCR assay (TaqMan, Applied Biosystems, Foster City, CA). We developed a method for closed-tube genotyping using two allele-specific MGB probes labeled with different fluorophores in one reaction. After PCR, tubes were transported to a fluorescence plate-reader for analysis of fluorescence. Common spreadsheet software was used for automated genotype assignment. As an example, DNA samples from 172 hemochromatosis patients were selected and tested for molecular defects in the HFE gene, i.e., mutations in codon 63 and 282. Tight genotype clusters were observed for both codons and results with MGB probes were identical to conventional genotyping (PCR + restriction-fragment-length-polymorphism). We show that this fast and easy method can be used for large-scale (high-throughput) genetic studies but also for routine molecular diagnostics without post-PCR manipulation of amplicons or the need for real-time quantitative PCR machines. Hum Mutat 19:554-559, 2002.  相似文献   
6.
The modulating effects of passive antibodies on both delayed hypersensitivity to the carrier and antibody synthesis to carrier and hapten determinants were studied in guinea pigs. Animals were injected with antibodies directed against either the carrier or the hapten prior to immunization with the hapten-carrier conjugate in Freund's complete adjuvant. Anti-hapten antibodies have been shown to have an enhancing effect on delayed hypersensitivity to the carrier and a suppressive effect on antibody synthesis to the hapten. In this experiment, anti-carrier anti-bodies seemed to have had no effect on delayed hypersensitivity to the carrier and on antibody synthesis to the hapten.  相似文献   
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Botulism is an uncommon severe neuromuscular disorder. We report two recent cases of confirmed infant botulism diagnosed in an 11-week and a 5-month-old infant along with electroneuromyogram (ENMG) findings. Then, we discuss the EMG features of infant botulism. In severe forms of infant botulism, presence of these features might help decide to use botulinum immune globulin. To our knowledge, case 1 is the first case reported in France based on confirmed dust contamination.  相似文献   
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