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91.
Hazelrigg SR Boley TM Cetindag IB Moulton KP Trammell GL Polancic JE Shawgo TS Quin JA Verhulst S 《The Annals of thoracic surgery》2004,77(3):824-830
BACKGROUND: Atrial fibrillation after coronary artery bypass is reported from 17% to 53%. Hypomagnesemia after this surgery is considered a contributing factor. METHODS: Two hundred-two coronary bypass patients were randomized to magnesium (n = 105) or placebo (n = 97). The experimental group received 80-mg magnesium sulfate per kilogram ideal weight in 100 mL dextrose 5% water 30 minutes preoperatively. Postoperatively, patients received 8-mg magnesium sulfate per kilogram ideal weight intravenous per hour more than 48 hours. The control group received dextrose 5% water at these intervals. RESULTS: After the first bolus serum magnesium was experimental 4.75 mg/dL versus control 1.91 mg/dL, p less than 0.001, and remained different until postoperative day 4 (experimental 2.33 mg/dL vs control 2.26 mg/dL, p = 0.24). Atrial appendage and strap muscle were analyzed after the first bolus and after revascularization. There were no differences between groups in tissue magnesium or calcium. Urinary magnesium was elevated in the experimental (experimental 324.5 mg/24 hours, vs control 45.1 mg/24 hours, p = 0.01). Calcium excretion was higher (experimental 370 mg/24 hours vs control 186 mg/24 hours, p < 0.001) and was associated with lower serum calcium. Serum calcium was higher in the control through the fourth postoperative day. The incidence of atrial fibrillation was experimental 32 of 105 (30.5%) versus control 41 of 97 (42.3%) p = 0.08. Atrial fibrillation was different on the first postoperative day (experimental 3/105, 2.9% vs control 9/97, 9.3%), p = 0.05. CONCLUSIONS: Overall prophylactic magnesium supplementation does not significantly reduce atrial and ventricular arrhythmias. The only significant benefit of magnesium supplementation was on the first postoperative day. 相似文献
92.
93.
De Bondt P De Winter O Vandenberghe S Vandevijver F Segers P Bleukx A Ham H Verdonck P Dierckx RA 《Nuclear medicine communications》2004,25(12):1197-1202
BACKGROUND: Automatic and semi-automatic algorithms to calculate ejection fraction (EF) from planar radionuclide ventriculography (PRV) have been used for many years in nuclear medicine. Validation of these algorithms is scarce and often performed on outdated versions of the software. Nevertheless, clinical trials where PRV is being used as the 'gold standard' for EF are numerous. Because of the importance attributed to the EF calculated by these programs, the accuracy of the resulting EF was assessed with a dynamic left ventricular physical phantom. METHODS: A dynamic left ventricular phantom was used to simulate 21 combinations of various ejection fractions (7-66%) and end diastolic volumes (27-290 ml). For each combination, a planar radionuclide ventriculograph was acquired, converted to an interfile format and transferred into processing stations with 10 different contemporaneously available commercial algorithms. The gold standard was the 'real' EF of the phantom, derived from the exact volume of the ventricle in end diastolic and end systolic position. Correlation and Bland-Altman analysis was performed between the real EF and the calculated EF. RESULTS: The correlation for all data was excellent (r=0.98), the mean difference was very acceptable (0.98%). Nevertheless, Bland-Altman analysis showed a significant trend in the difference between real and calculated EF, with a growing underestimation for higher ranges of EF, due to an overestimation of background in larger volumes compared to smaller ones. CONCLUSION: The determination of EF from PRV, calculated with commercially available algorithms, correlates closely to the real EF of a dynamic left ventricular phantom. This phantom can be used in the development and validation of algorithms for PRV studies, in software audits and in quality assurance procedures. 相似文献
94.
Fairbanks TJ De Langhe S Sala FG Warburton D Anderson KD Bellusci S Burns RC 《Journal of pediatric surgery》2004,39(3):360-365
Background/purpose
Anorectal malformations occur in 1 per 4,000 live births and represent a surgical challenge. Although critically important, the basic mechanisms of normal anorectal union are incompletely understood. Fgf10 signaling is known to serve a key role in mesenchymal/epithelial interactions in many organ systems including the gastrointestinal tract (GIT). The authors therefore hypothesized that Fgf10 signaling has a central role in normal anorectal development.Methods
Fgf10 expression in wild-type (Wt) embryos was evaluated using whole-mount in situ hybridization. Wt and Fgf10−/− embryos were harvested from timed pregnant mothers at E12.5 through E17.5 and were analyzed for anorectal phenotype.Results
Wt development of union between anorectal structures is completed between E12.5 and E13.5 with luminal communication between distal rectal epithelium and anus. Fgf10 is discreetly expressed at E12.5 in the distal rectum. Fgf10−/− mutants show failure of union of the rectum and anus at an early stage (E13.5) and near term (E17.5).Conclusions
Fgf10 is expressed in the rectum at the time when anorectal continuity is established, indicating a role in normal anorectal development. Fgf10 invalidation (Fgf10−/− mutant) results in a genetically reproducible anorectal malformation phenotype. Fgf10 function is critical for normal anorectal development. 相似文献95.
96.
Vandevelde S Broekaert E Yates R Kooyman M 《The International journal of social psychiatry》2004,50(1):66-79
BACKGROUND: The correction-based therapeutic community (TC) is one of the most described treatment modalities for (substance abusing) incarcerated offenders. The origins and development of the therapeutic community have been traced back to two independent traditions: the American hierarchical concept-based TC and the British democratic Maxwell Jones-type TC. Both branches have developed independently, targeting different people and tackling diverse problems. AIMS: To demonstrate that there are clear and undeniable similarities between the 'two' prison-based therapeutic communities. METHOD: A comparative historical review of the literature and a critical discussion and comparison. RESULTS: The links between the democratic and hierarchical therapeutic communities are summarised under five headings: social learning and behavioural modification; permissiveness and modelling; democracy and hierarchy; communalism and community as method; reality testing and 'acting as if'. CONCLUSIONS: The 'two' correction-based therapeutic communities are on converging pathways. Far from being oppositional models, they can be regarded as being complementary. 相似文献
97.
Growth, development and health from early fetal life until young adulthood: the Generation R Study 总被引:8,自引:0,他引:8
Hofman A Jaddoe VW Mackenbach JP Moll HA Snijders RF Steegers EA Verhulst FC Witteman JC Büller HA 《Paediatric and perinatal epidemiology》2004,18(1):61-72
In this paper the Generation R Study is presented. This study examines growth, development and health in urban children from fetal life until young adulthood. With an integrated approach of epidemiological, clinical and basic research, it focuses on four primary areas of research: (1) growth and physical development; (2) behavioural and cognitive development; (3) diseases in childhood; and (4) health and health care for pregnant women and children. The general aims of the study are: 1. to describe normal and abnormal growth, development and health from fetal life until young adulthood in a multiethnic population-based cohort; 2. to identify biological, social and environmental determinants of normal and abnormal growth, development and health from fetal life until adulthood; 3. to examine the utilisation and effectiveness of current strategies for prevention and early identification of groups at risk. Eventually, this study will contribute to the development of strategies for optimising health and health care for pregnant women and children. The Generation R Study is a prospective population-based cohort study in Rotterdam, the Netherlands. In this urban setting, 10 000 children will be examined from early fetal life until young adulthood. Data are collected by physical examinations, questionnaires, interviews, ultrasound and biological samples. The study entered its pilot phase to test the logistics in December 2001. Full participant recruitment and complete data collection started in 2002. 相似文献
98.
Verhulst L Waggie Z Hatherill M Reynolds L Argent A 《Archives of disease in childhood》2002,86(5):352-355
Aims: To document the patterns of presentation and outcome of severe anticholinesterase insecticide poisoning in children requiring intensive care. Methods: Retrospective case note review of all 5541 children admitted to the paediatric intensive care unit (PICU) of a university hospital during the 10 years from January 1990 to May 2000. Fifty four children (1%) with anticholinesterase insecticide poisoning were identified. Presenting features, route of exposure, treatment, complications, and mortality were recorded. Data were analysed by the Fisher''s exact and Mann–Whitney tests. Results: More children than expected were from a rural area (46% versus 25%). Decontamination occurred in 50% of children prior to PICU admission. Enteral exposure was most common (n = 27; 50%). Median pseudocholinesterase level was 185 IU/l (range 75–7404). Median total dose of atropine required to maintain mydriasis was 0.3 mg/kg (range 0.03–16.7) over a median of 10 hours (range 1–160). Complications included coma (31%), seizures (30%), shock (9%), arrhythmias (9%), and respiratory failure requiring ventilation (35%). No significant differences were detected in incidence of seizures, cardiac arrhythmias, respiratory failure, mortality, duration of ventilation, or PICU stay, according to route of exposure, or state of decontamination. Four children died (7%). Mortality was associated with the presence of a cardiac arrhythmia (likelihood ratio 8.3) and respiratory failure (likelihood ratio 3.3). Conclusion: The mortality and morbidity of severe anticholinesterase insecticide poisoning in childhood is not related to route of exposure, or to delay in decontamination. However, the presence of either a cardiac arrhythmia or respiratory failure is associated with a poor prognosis. 相似文献
99.
Reduced postischemic macrophage infiltration and interstitial fibrosis in osteopontin knockout mice 总被引:10,自引:0,他引:10
BACKGROUND: Osteopontin (OPN) is a phosphoprotein that is up-regulated in several experimental models of renal disease, including ischemia/reperfusion injury. OPN has been described as a macrophage chemoattractant, may serve as a survival factor for tubular cells, and is implicated in the development of tubulointerstitial fibrosis. However, the precise role of this protein in renal pathophysiology remains unclear. METHODS: OPN knockout and wild-type mice were subjected to 30 minutes of warm renal ischemia combined with a contralateral nephrectomy, and sacrificed at six different time points, ranging from 12 hours to seven days after reperfusion. Besides functional and morphological parameters of postischemic acute renal failure (ARF), macrophage infiltration, apoptosis and expression of collagen types I and IV were investigated. RESULTS: Postischemic ARF in OPN knockouts and wild-types showed a similar course and severity, without significant differences in either functional or morphological disease parameters. However, macrophage infiltration was significantly diminished in OPN knockouts after five and seven days, in cortex as well as in the outer stripe of the outer medulla (OSOM). Furthermore, OPN knockout mice showed significantly enhanced apoptosis in the injury phase and significantly less collagen I and IV expression in the regeneration phase of postischemic ARF. CONCLUSIONS: There was no influence of OPN protein on the severity or course of functional impairment or morphological injury in the first seven days after an ischemic insult to the kidney. However, our results demonstrate that OPN favors macrophage recruitment to the postischemic kidney, inhibits apoptosis, and stimulates the development of renal fibrosis after an acute ischemic insult. 相似文献
100.
Reijneveld SA Vogels AG Brugman E van Ede J Verhulst FC Verloove-Vanhorick SP 《European journal of public health》2003,13(2):152-159
BACKGROUND: Psychosocial problems, such as behavioural, emotional, and educational problems, are highly prevalent among children and adolescents. Early treatment may reduce these problems, if accurately identified. Validated questionnaires may support identification. The aim of this study is to assess the psychometric qualities of such a questionnaire, the Short Indicative Questionnaire for Psychosocial problems among Adolescents (KIVPA,) and to determine whether it is suitable for and adds to the early detection of psychosocial problems among adolescents. METHODS: Data came from a national sample of 1,440 Dutch adolescents, using the KIVPA, the Child Behavior Checklist (CBCL), and the Youth Self-Report (YSR). Of these, 1,248 provided data on all questionnaires (77.8%). The scale structure of the KIVPA was assessed; its sensitivity and specificity using CBCL, YSR and referral for psychosocial problems as criteria; and its contribution to detecting CBCL and YSR problems. RESULTS: The KIVPA is mostly uni-dimensional but the variance explained by its main factor is relatively low. The total KIVPA score discriminates between adolescents with and without problems on the three criteria. Using a clinical YSR total problem score as criterion, sensitivity and specificity are 0.82 and 0.85, respectively, at the proposed cut-off (area under the ROC curve: 0.92; 95% confidence interval (CI) 0.90-0.95). The odds ratio of a clinical YSR score for an elevated KIVPA score is 29.1 (95% CI: 14.4-59.1), although the KIVPA mainly covers internalizing problems. CONCLUSION: The KIVPA has added value in the early detection of internalizing psychosocial problems, but is not sufficiently efficient. 相似文献