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991.
BACKGROUND: By assessing current surgical outcome and symptomatic relief, this study attempts to answer whether atrial septal defects in adults should be closed. METHODS: Thirty-nine adult patients aged 35.2 +/- 13.6 years underwent operation for an atrial septal defect between June 1988 and June 1994. Indications for closure were symptoms (33 patients) or a significant left-to-right atrial shunt (6 patients). Data were obtained from hospital records, and the latest status of the patients was determined by a written questionnaire. RESULTS: There were no deaths. Pulmonary embolism in 1 patient was the only complication observed. The QRS duration on the surface electrocardiogram decreased immediately (p < 0.001), and the cardiothoracic ratio on chest radiographs was significantly lower 3 to 6 months after operation (p < 0.001), both findings reflecting improved hemodynamics. No residual shunts were seen on follow-up (mean follow-up, 3.3 +/- 2.2 years). Twenty-seven (81.8%) of the 33 symptomatic patients improved clinically in terms of exercise performance, atrial arrhythmias, or both. Three (50%) of the 6 previously asymptomatic patients reported improved functional capacity post-operatively. CONCLUSIONS: Today, operation for atrial septal defects in adults can be performed with no mortality and low morbidity and results in symptomatic improvement in the majority of patients. Clinical improvement was seen even in patients who considered themselves asymptomatic preoperatively. We advocate closure of atrial septal defects in adult patients with symptoms or significant atrial shunts.  相似文献   
992.
This paper argues that there is a difference between how software development project managers perceive the task of estimating project costs and duration and the way in which commercially available estimating tools are designed to be used. A model of the early estimating/planning stages of a project (the EEPS model) is presented which suggests estimation could be first carried out either before or during the first detailed planning stage. A survey was carrried out which confirmed that project managers typically perceive the ‘true’ process of estimation as being part of planning. This result may explain why estimating tools are not widely used: planning tools are being used instead. By making a temporal distinction between the points at which project information first becomes available, however, it can also be seen that even planning must be driven by some assessment of the size and complexity of a project. At this point only estimating tools are available to provide such estimates. The conclusion seems to be that estimating tools do have a role to play in project management, but they must be explicitly task-based in order to fit the way in which project managers currently perceive estimation.  相似文献   
993.
If a patient adheres to religious values and practices, should the treating psychologist get input from a clergyperson? How frequent is clergy–psychologist collaboration? What obstacles impede such collaboration? An exploratory survey questionnaire was sent to 200 clergy, 200 psychologists interested in religious issues, and 200 psychologists selected without regard to religious interests or values. Four themes were assessed: types of collaborative activities, frequency of collaboration, obstacles to collaboration, and ways to enhance collaboration. Strategies for promoting clergy–psychologist collaboration include challenging unidirectional referral assumptions, building trust through proximity and familiarity, and considering the importance of shared values and beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
Bacterial lipopolysaccharide (LPS) has been previously shown to down-regulate the mRNA and protein expression of the hepatic cytochrome P450 (P450) isozymes 2C11 and 2C12. In this study, we examined the effects of LPS on the constitutive expression of P4503A2, P4502E1, and the P4504A subfamily in the rat. Fischer 344 and Sprague-Dawley rats were each administered 1 mg/kg LPS intraperitoneally and killed for hepatic RNA and microsome isolation at different times. LPS treatment was found to suppress P4502C11, P4503A2, and P4502E1 protein and mRNA expression in both strains of rat. Total microsomal P450 levels decreased by 30%, which was smaller than the effects on the levels of individual isozymes. The magnitude of suppression exhibited in the Sprague-Dawley rats, however, seemed to be more variable than that in the F344 strain. The mRNAs of all three of the P4504A subfamily members were induced 2- to 6-fold in the F344 rat livers after LPS administration. P4504A3 protein expression increased 2-fold, whereas P4504A1/2 protein levels decreased by 30%. Lauric acid omega-hydroxylase activity increased 1.6-fold in LPS-treated Fischer 344 rats and omega-1-hydroxylase activity decreased by 38%. In the Sprague-Dawley strain, however, decreases were seen in both omega- and omega-1-hydroxylase activities after LPS treatment. Our data demonstrate that LPS administration induces P4504A subfamily mRNA and P4504A3 protein expression. Furthermore, our findings also suggest strain differences in both suppression and induction of P450s between the Sprague-Dawley and F344 rats.  相似文献   
995.
The high affinity streptavidin (or avidin)/biotin system is being investigated for imaging and radiotherapy procedures. Streptavidin (SA) and avidin exhibit markedly different pharmacokinetics, with avidin clearing from the blood much faster than SA. To optimize blood clearance kinetics, SA and avidin were biochemically modified and analyzed in vitro and in vivo. METHODS: Galactose moieties were covalently attached to promote binding by hepatocyte galactose receptors and hasten SA clearance. To prolong avidin clearance, avidin was deglycosylated and/or neutralized by acetylation of its lysine amino acids. In vitro, the modified proteins were analyzed by isoelectric focusing, SDS polyacrylamide electrophoresis and a biotin binding saturation assay. The modified and native proteins were radiolabeled with 131I and injected into rabbits for pharmacokinetic, redistribution and imaging analysis. RESULTS: For SA, the resulting increase in blood clearance and liver accumulation was correlated to the amount of galactose bound to SA. For avidin, each type of modification increased its circulation time, with the slowest clearance resulting from a combination of deglycosylation and neutralization. CONCLUSION: Biochemical modification of SA and avidin resulted in altered pharmacokinetics compared to the native proteins. Modified SA or avidin, when cross-linked with a lesion-specific targeting agent, may be applicable for rapid two-step in vivo imaging techniques.  相似文献   
996.
Sudden, unexpected cardiac death in the age group 1 to 21 years usually is due to myocarditis, hypertrophic cardiomyopathy, aortic valvar stenosis, and coronary arterial abnormalities. The hearts of 70 patients <21 years of age who died suddenly were reviewed. Twenty patients were <1 year of age and 50 were 1 to 21 years old. The cardiac findings were compared with those in 68 age-matched controls with known cardiac disease who did not die suddenly. Significant cardiac abnormalities were present in 13 (65%) of the 20 infants; 10 (50%) had anomalies of the aortic origin of the coronary arteries. Among the 50 older patients, cardiac abnormalities were found in 40 (80%), among whom coronary arterial anomalies existed in 12 (24%). Anomalies of aortic origin more frequently involved the left main than the right coronary artery in both groups.  相似文献   
997.
998.
BACKGROUND: This study is comprised of 3493 consecutive patients who underwent open heart surgery at our institution. Data on all patients were collected prospectively. METHODS: In 45 patients (Group P) (1.3%), a permanent pacemaker (PP) was inserted postoperatively. For the purpose of the study, these patients were compared to 3448 patients (Group NP) who did not require insertion of a PP after surgery. Mean follow-up was 33 months (range 1.5 to 66). RESULTS: We found Group P patients were older (64.8 +/- 11.0 vs 61.0 +/- 11.0 years, p < 0.05), had a higher proportion of elderly (> 70 years) 36% vs 19%, p = 0.01), and of female patients (48.8% vs 22.7%, p < 0.001) compared to Group NP. Group P also had a higher incidence of preoperative rhythm abnormalities (26.6% vs 5.7%, p < 0.0001), redo surgery (13.3% vs 4.6%, p = 0.02), aortic valve surgery (48.8% vs 10.8%, p < 0.001), and tricuspid valve surgery (repair 3, replacement 1) (8.8% vs 0.5%, p < 0.001), in addition to a higher proportion of patients in whom cold (vs warm) blood cardioplegia was used (68.8% vs 52.3%, p = 0.03). Indication for postoperative PP was sick sinus syndrome (SSS) in nine patients; atrial fibrillation in eight patients; atrioventricular block (AVB) in 27 patients; and combined AVB/SSS in 1 patient. There were no operative deaths in Group P. Necessity for PP after heart surgery had a significant impact on resource utilization resulting in prolonged ventilation (3.1 +/- 7.5 vs 1.4 +/- 3.3 days, p < 0.01), intensive care unit (5.1 +/- 10.2 vs 2.5 +/- 4.0 days, p < 0.01), and postoperative hospital stay (18.0 +/- 13.4 vs 8.1 +/- 9.4 days, p < 0.01). CONCLUSIONS: By multivariate logistic regression (odds ratio and p value in parentheses), aortic valve surgery (8.23, p = 0.001), the absence of preoperative sinus rhythm (5.60, p = 0.001), postoperative myocardial infarction (3.46, p = 0.024), and female gender (2.52, p = 0.003), were found to be independent predictors for PP requirement post surgery.  相似文献   
999.
PURPOSE: The hardness, porosity, and adaptation of removable partial dentures fabricated with one heat-polymerized denture base resin and two resins designed for microwave polymerization were evaluated. MATERIALS AND METHODS: Five prostheses were evaluated for each resin. Adaptation of the denture bases to the master cast was evaluated by spatial orientation and mean weight of residual impression material. The prostheses were than embedded in epoxy resin and sectioned for evaluation of resin hardness (Knoop hardness) and microporosity. RESULTS: There were no significant differences in the adaptation of the acrylic resin bases for Acron MC and Ch Lucitone. There was no significant difference in the mean Knoop hardness values for any of the resin bases near and away from the metal. None of the denture bases showed porosity greater than 100 microns. CONCLUSIONS: Both resin bases formulated for microwave polymerization were effectively polymerized around metal frameworks without adverse effects on resin hardness or porosity. Justi Denture Base material had poorer base adaptation than the other two resins.  相似文献   
1000.
How should iterators be abstracted and encapsulated in modern imperative languages? We consider the combined impact of several factors on this question: the need for a common interface model for user defined iterator abstractions, the importance of formal methods in specifying such a model, and problems involved in modular correctness proofs of iterator implementations and clients. A series of iterator designs illustrates the advantages of the swapping paradigm over the traditional copying paradigm. Specifically, swapping based designs admit more efficient implementations while offering relatively straightforward formal specifications and the potential for modular reasoning about program behavior. The final proposed design schema is a common interface model for an iterator for any generic collection  相似文献   
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